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    <context id="C000234190_GD_BR_Member">
        <entity>
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            <segment>
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        <period>
            <instant>2026-08-31</instant>
        </period>
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    <context id="C000234190_GD_DO_Member">
        <entity>
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            <segment>
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            <instant>2026-08-31</instant>
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        <entity>
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            <segment>
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            <instant>2026-08-31</instant>
        </period>
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    <context id="C000234190_GD_FR_Member">
        <entity>
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            <segment>
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            <instant>2026-08-31</instant>
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        <entity>
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            <segment>
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            <instant>2026-08-31</instant>
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            <instant>2026-08-31</instant>
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    <unit id="usd">
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    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000019124_ClassMember" id="ixv-140">This annual shareholder report contains information about Fidelity&#xae; Investment Grade Bond Fund for the period September 1, 2025 to August 31, 2026.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000019124_ClassMember" id="ixv-142">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000019124_ClassMember" id="ixv-147">You can find additional information about the Fund at fundresearch.fidelity.com/prospectus/sec. You can also request this information by contacting us at 1-877-208-0098 or by sending an e-mail to fidfunddocuments@fidelity.com.</oef:AddlInfoTextBlock>
    <oef:AddlInfoWebsite contextRef="C000019124_ClassMember" id="ixv-149">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000019124_ClassMember" id="ixv-152">1-877-208-0098</oef:AddlInfoPhoneNumber>
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    <oef:ExpensesTextBlock contextRef="C000019124_ClassMember" id="ixv-162">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What were your Fund costs for the last year?&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(based on hypothetical $10,000 investment)&lt;/span&gt;&lt;/div&gt;
&lt;div&gt;&lt;span style="font-size:11px;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:bold;"&gt;FUND COST (PREVIOUS YEAR)&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;table cellpadding="0" cellspacing="0" style="border-collapse:collapse;border-style:none;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:51%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:21%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;Costs of a $10,000 investment&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:27%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;Costs paid as a percentage of a $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:51%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;Class M&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:21%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;75&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:27%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;0.75&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:ExpensesTextBlock>
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    <oef:FactorsAffectingPerfTextBlock contextRef="C000019124_ClassMember" id="ixv-205">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What affected the Fund's performance this period?&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;U.S. taxable investment-grade bonds achieved a gain for the 12 months ending August 31, 2026, buoyed by three policy interest-rate cuts by the Federal Reserve in late 2025, but pulled down since then by rising bond yields amid higher consumer inflation, a resilient economy and heavy U.S. Treasury issuance.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Against this backdrop, the fund's top contributors relative to its benchmark, the Bloomberg U.S. Aggregate Bond Index, for the fiscal year came from overweight allocations to securitized products - specifically, outperforming stakes in asset-backed securities, including AAA-rated collateralized loan obligations, and commercial mortgage-backed securities.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Converserly, the fund's yield-curve positioning and its modestly longer-than-benchmark duration in a rising-rate environment modestly detracted.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;An underweight in agency mortgage-backed securities also modestly hindered performance.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;In terms of security selection, picks in corporate debt, sovereign government bonds and commercial mortgage-backed securities helped.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;The fund's managers did not make significant adjustments in positioning over the period and sought to keep the fund conservatively positioned versus the benchmark.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:FactorsAffectingPerfTextBlock>
    <oef:LineGraphTableTextBlock contextRef="C000019124_ClassMember" id="ixv-229">How did the Fund perform over the past 10 years?

 &#160;&#160;
CUMULATIVE PERFORMANCE
August 31, 2016 through August 31, 2026. 
Initial investment of $10,000&#160;and the current sales charge was paid.
Class M


$9,600

$9,697


$9,574


$10,540


$11,415


$11,504


$10,134


$10,039


$10,792


$11,130


$11,268



Bloomberg U.S. Aggregate Bond Index


$10,000

$10,049


$9,944


$10,955


$11,665


$11,655


$10,313


$10,189


$10,933


$11,276


$11,489



&#160;

2016

2017

2018

2019

2020

2021

2022

2023

2024

2025

2026









&#160;
</oef:LineGraphTableTextBlock>
    <oef:LineGraphAndTableMeasureName contextRef="C000019124_LG_ClassMember_11YR" id="ixv-250">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Class M&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000019124_ClassMember_AsOf_2016"
      decimals="0"
      id="ixv-353742"
      unitRef="usd">9600</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019124_ClassMember_AsOf_2017"
      decimals="0"
      id="ixv-353743"
      unitRef="usd">9697</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019124_ClassMember_AsOf_2018"
      decimals="0"
      id="ixv-353744"
      unitRef="usd">9574</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019124_ClassMember_AsOf_2019"
      decimals="0"
      id="ixv-353745"
      unitRef="usd">10540</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019124_ClassMember_AsOf_2020"
      decimals="0"
      id="ixv-353746"
      unitRef="usd">11415</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019124_ClassMember_AsOf_2021"
      decimals="0"
      id="ixv-353747"
      unitRef="usd">11504</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019124_ClassMember_AsOf_2022"
      decimals="0"
      id="ixv-353748"
      unitRef="usd">10134</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019124_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-353749"
      unitRef="usd">10039</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019124_ClassMember_AsOf_2024"
      decimals="0"
      id="ixv-353750"
      unitRef="usd">10792</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019124_ClassMember_AsOf_2025"
      decimals="0"
      id="ixv-353751"
      unitRef="usd">11130</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019124_ClassMember_AsOf_2026"
      decimals="0"
      id="ixv-353752"
      unitRef="usd">11268</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000019124_LG_1_AdditionalIndexMember_11YR"
      id="ixv-299">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg U.S. Aggregate Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000019124_1_AdditionalIndexMember_AsOf_2016"
      decimals="0"
      id="ixv-353753"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019124_1_AdditionalIndexMember_AsOf_2017"
      decimals="0"
      id="ixv-353754"
      unitRef="usd">10049</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019124_1_AdditionalIndexMember_AsOf_2018"
      decimals="0"
      id="ixv-353755"
      unitRef="usd">9944</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019124_1_AdditionalIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-353756"
      unitRef="usd">10955</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019124_1_AdditionalIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-353757"
      unitRef="usd">11665</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019124_1_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-353758"
      unitRef="usd">11655</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019124_1_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-353759"
      unitRef="usd">10313</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019124_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-353760"
      unitRef="usd">10189</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019124_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-353761"
      unitRef="usd">10933</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019124_1_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-353762"
      unitRef="usd">11276</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019124_1_AdditionalIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-353763"
      unitRef="usd">11489</oef:AccmVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000019124_ClassMember" id="ixv-400">AVERAGE ANNUAL TOTAL RETURNS:

&#160;

1 Year

5 Year

10 Year


Class M (incl. 4.00% sales charge) &#160;

-2.81%

-1.22%


1.20%


Class M (without 4.00% sales charge)

1.24%

-0.41%

1.62%


Bloomberg U.S. Aggregate Bond Index

1.89%


-0.29%


1.40%




&#160;
&#160;
Visit institutional.fidelity.com for more recent performance information.&#160;

&#160;


The Fund's past performance is not a good predictor of the Fund's future performance. &#160;The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.





</oef:AvgAnnlRtrTableTextBlock>
    <oef:AvgAnnlRtrPct
      contextRef="C000019124_ClassMember_1YR"
      decimals="INF"
      id="ixv-353764"
      unitRef="pure">-0.0281</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019124_ClassMember_5YR"
      decimals="INF"
      id="ixv-353765"
      unitRef="pure">-0.0122</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019124_ClassMember_10YR"
      decimals="INF"
      id="ixv-353766"
      unitRef="pure">0.0120</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019124_NoLoadClassMember_1YR"
      decimals="INF"
      id="ixv-353767"
      unitRef="pure">0.0124</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019124_NoLoadClassMember_5YR"
      decimals="INF"
      id="ixv-353768"
      unitRef="pure">-0.0041</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019124_NoLoadClassMember_10YR"
      decimals="INF"
      id="ixv-353769"
      unitRef="pure">0.0162</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019124_0_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-353770"
      unitRef="pure">0.0189</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019124_0_BBIndexMember_5YR"
      decimals="INF"
      id="ixv-353771"
      unitRef="pure">-0.0029</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019124_0_BBIndexMember_10YR"
      decimals="INF"
      id="ixv-353772"
      unitRef="pure">0.0140</oef:AvgAnnlRtrPct>
    <oef:UpdPerfInfoLocationTextBlock contextRef="C000019124_ClassMember" id="ixv-474">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Visit &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;institutional.fidelity.com&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt; for more recent performance information.&lt;/span&gt;</oef:UpdPerfInfoLocationTextBlock>
    <oef:PerformancePastDoesNotIndicateFuture contextRef="C000019124_ClassMember" id="ixv-486">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:italic;font-weight:normal;"&gt;The Fund's past performance is not a good predictor of the Fund's future performance.&lt;/span&gt;</oef:PerformancePastDoesNotIndicateFuture>
    <oef:NoDeductionOfTaxesTextBlock contextRef="C000019124_ClassMember" id="ixv-490">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.&lt;/span&gt;</oef:NoDeductionOfTaxesTextBlock>
    <oef:AddlFundStatisticsTextBlock contextRef="C000019124_ClassMember" id="ixv-496">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;Key Fund Statistics&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(as of August 31, 2026)&lt;/span&gt;&lt;/div&gt;
&lt;div&gt;&lt;span style="font-size:11px;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;table cellpadding="0" cellspacing="1" style="border-collapse:separate;border-style:none;margin:auto;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:63%; " valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:bold;"&gt;KEY FACTS&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt; &lt;span&gt;&#160;&lt;/span&gt;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fund Size&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;11,833,010,166&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;4,328&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;32,938,746&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="middle"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Portfolio Turnover&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;142&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:AddlFundStatisticsTextBlock>
    <us-gaap:AssetsNet
      contextRef="C000019124_InstantMember"
      decimals="0"
      id="ixv-353773"
      unitRef="usd">11833010166</us-gaap:AssetsNet>
    <oef:HoldingsCount
      contextRef="C000019124_InstantMember"
      decimals="INF"
      id="ixv-353774"
      unitRef="holding">4328</oef:HoldingsCount>
    <oef:AdvisoryFeesPaidAmt
      contextRef="C000019124_ClassMember"
      decimals="0"
      id="ixv-353775"
      unitRef="usd">32938746</oef:AdvisoryFeesPaidAmt>
    <us-gaap:InvestmentCompanyPortfolioTurnover
      contextRef="C000019124_ClassMember"
      decimals="INF"
      id="ixv-353776"
      unitRef="pure">1.42</us-gaap:InvestmentCompanyPortfolioTurnover>
    <oef:HoldingsTableTextBlock contextRef="C000019124_ClassMember" id="ixv-575">
&#160;
U.S. Government and U.S. Government Agency Obligations

61.0


AAA

5.5


AA

0.9


A

7.7


BBB

15.4


BB

2.9


B

0.8


CCC,CC,C

0.0


Not Rated

9.3




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

U.S. Government and U.S. Government Agency Obligations - 61.0


&#160;

AAA - 5.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

AA - 0.9&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

A - 7.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BBB - 15.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BB - 2.9&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

B - 0.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

CCC,CC,C - 0.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Not Rated - 9.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


Short-Term Investments and Net Other Assets (Liabilities) - (3.5)% 


&#160;


We have used ratings from Moody's Investors Service, Inc. Where Moody's&#xae; ratings are not available, we have used S&amp;P&#xae; ratings. All ratings are as of the date indicated and do not reflect subsequent changes.




&#160;
&#160;
&#160;
&#160;
U.S. Treasury Obligations

44.6


Corporate Bonds

24.3


U.S. Government Agency - Mortgage Securities

16.4


Asset-Backed Securities

9.2


CMOs and Other Mortgage Related Securities

8.7


Preferred Securities

0.2


Other Investments

0.1


Bank Loan Obligations

0.0


Options

0.0




ASSET ALLOCATION (% of Fund's net assets)


&#160;



&#160;

U.S. Treasury Obligations - 44.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Corporate Bonds - 24.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

U.S. Government Agency - Mortgage Securities - 16.4


&#160;

Asset-Backed Securities - 9.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

CMOs and Other Mortgage Related Securities - 8.7


&#160;

Preferred Securities - 0.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Other Investments - 0.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Bank Loan Obligations - 0.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Options - 0.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


Short-Term Investments and Net Other Assets (Liabilities) - (3.5)%


&#160;






United States

91.4


Grand Cayman (UK Overseas Ter)

4.4


Mexico

0.7


Bailiwick Of Jersey

0.7


Ireland

0.6


United Kingdom

0.5


Germany

0.3


Switzerland

0.3


Japan

0.2


Others

0.9




GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

United States - 91.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Grand Cayman (UK Overseas Ter) - 4.4&#160;&#160;&#160;&#160;


&#160;

Mexico - 0.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Bailiwick Of Jersey - 0.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Ireland - 0.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

United Kingdom - 0.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Germany - 0.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Switzerland - 0.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Japan - 0.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Others - 0.9&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;




&#160;




&#160;
&#160;
</oef:HoldingsTableTextBlock>
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      id="ixv-353777"
      unitRef="pure">0.610</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019124_QD_AAA_Member"
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      id="ixv-353778"
      unitRef="pure">0.055</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-353779"
      unitRef="pure">0.009</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-353780"
      unitRef="pure">0.077</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019124_QD_BBB_Member"
      decimals="INF"
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      unitRef="pure">0.154</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-353782"
      unitRef="pure">0.029</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019124_QD_B_Member"
      decimals="INF"
      id="ixv-353783"
      unitRef="pure">0.008</oef:PctOfNav>
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      decimals="INF"
      id="ixv-353784"
      unitRef="pure">0.000</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-353785"
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    <oef:PctOfNav
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      decimals="INF"
      id="ixv-353786"
      unitRef="pure">0.446</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019124_AA_CorporateBonds_Member"
      decimals="INF"
      id="ixv-353787"
      unitRef="pure">0.243</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019124_AA_USGovernmentAgencyMortgageSecurities_Member"
      decimals="INF"
      id="ixv-353788"
      unitRef="pure">0.164</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019124_AA_AssetBackedSecurities_Member"
      decimals="INF"
      id="ixv-353789"
      unitRef="pure">0.092</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019124_AA_CMOsandOtherMortgageRelatedSecurities_Member"
      decimals="INF"
      id="ixv-353790"
      unitRef="pure">0.087</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019124_AA_PreferredSecurities_Member"
      decimals="INF"
      id="ixv-353791"
      unitRef="pure">0.002</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019124_AA_OtherInvestments_Member"
      decimals="INF"
      id="ixv-353792"
      unitRef="pure">0.001</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019124_AA_BankLoanObligations_Member"
      decimals="INF"
      id="ixv-353793"
      unitRef="pure">0.000</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019124_AA_Options_Member"
      decimals="INF"
      id="ixv-353794"
      unitRef="pure">0.000</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019124_GD_US_Member"
      decimals="INF"
      id="ixv-353795"
      unitRef="pure">0.914</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019124_GD_GrandCaymanUKOverseasTer_Member"
      decimals="INF"
      id="ixv-353796"
      unitRef="pure">0.044</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019124_GD_MX_Member"
      decimals="INF"
      id="ixv-353797"
      unitRef="pure">0.007</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019124_GD_BailiwickOfJersey_Member"
      decimals="INF"
      id="ixv-353798"
      unitRef="pure">0.007</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019124_GD_IE_Member"
      decimals="INF"
      id="ixv-353799"
      unitRef="pure">0.006</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019124_GD_GB_Member"
      decimals="INF"
      id="ixv-353800"
      unitRef="pure">0.005</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019124_GD_DE_Member"
      decimals="INF"
      id="ixv-353801"
      unitRef="pure">0.003</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019124_GD_CH_Member"
      decimals="INF"
      id="ixv-353802"
      unitRef="pure">0.003</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019124_GD_JP_Member"
      decimals="INF"
      id="ixv-353803"
      unitRef="pure">0.002</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019124_GD_Other_Member"
      decimals="INF"
      id="ixv-353804"
      unitRef="pure">0.009</oef:PctOfNav>
    <oef:LargestHoldingsTableTextBlock contextRef="C000019124_ClassMember" id="ixv-1044">TOP HOLDINGS(% of Fund's net assets)

&#160;

&#160;


US Treasury Notes

34.3


&#160;


US Treasury Bonds

10.3


&#160;


Fannie Mae Mortgage pass-thru certificates

5.3


&#160;


Freddie Mac Gold Pool

4.4


&#160;


Ginnie Mae II Pool

3.8


&#160;


Uniform Mortgage Backed Securities

2.4


&#160;


Freddie Mac Multifamily Structured pass-thru certificates

2.2


&#160;


Citigroup Inc

1.2


&#160;


Bank of America Corp

1.1


&#160;


JPMorgan Chase &amp; Co

0.9


&#160;


&#160;

65.9

&#160;



</oef:LargestHoldingsTableTextBlock>
    <oef:PctOfNav
      contextRef="C000019124_TH_0_Member"
      decimals="INF"
      id="ixv-353805"
      unitRef="pure">0.343</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019124_TH_1_Member"
      decimals="INF"
      id="ixv-353806"
      unitRef="pure">0.103</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019124_TH_2_Member"
      decimals="INF"
      id="ixv-353807"
      unitRef="pure">0.053</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019124_TH_3_Member"
      decimals="INF"
      id="ixv-353808"
      unitRef="pure">0.044</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019124_TH_4_Member"
      decimals="INF"
      id="ixv-353809"
      unitRef="pure">0.038</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019124_TH_5_Member"
      decimals="INF"
      id="ixv-353810"
      unitRef="pure">0.024</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019124_TH_6_Member"
      decimals="INF"
      id="ixv-353811"
      unitRef="pure">0.022</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019124_TH_7_Member"
      decimals="INF"
      id="ixv-353812"
      unitRef="pure">0.012</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019124_TH_8_Member"
      decimals="INF"
      id="ixv-353813"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019124_TH_9_Member"
      decimals="INF"
      id="ixv-353814"
      unitRef="pure">0.009</oef:PctOfNav>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-1215">2026-08-31</dei:DocumentPeriodEndDate>
    <oef:FundName contextRef="C000019123_ClassMember" id="ixv-1227">Fidelity&#xae; Investment Grade Bond Fund</oef:FundName>
    <oef:ClassName contextRef="C000019123_ClassMember" id="ixv-1230">Fidelity Advisor&#xae; Investment Grade Bond Fund Class C</oef:ClassName>
    <dei:TradingSymbol contextRef="C000019123_ClassMember" id="ixv-1234">FGBCX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000019123_ClassMember" id="ixv-1253">This annual shareholder report contains information about Fidelity&#xae; Investment Grade Bond Fund for the period September 1, 2025 to August 31, 2026.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000019123_ClassMember" id="ixv-1255">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000019123_ClassMember" id="ixv-1260">You can find additional information about the Fund at fundresearch.fidelity.com/prospectus/sec. You can also request this information by contacting us at 1-877-208-0098 or by sending an e-mail to fidfunddocuments@fidelity.com.</oef:AddlInfoTextBlock>
    <oef:AddlInfoWebsite contextRef="C000019123_ClassMember" id="ixv-1262">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000019123_ClassMember" id="ixv-1265">1-877-208-0098</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000019123_ClassMember" id="ixv-1268">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000019123_ClassMember" id="ixv-1275">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What were your Fund costs for the last year?&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(based on hypothetical $10,000 investment)&lt;/span&gt;&lt;/div&gt;
&lt;div&gt;&lt;span style="font-size:11px;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:bold;"&gt;FUND COST (PREVIOUS YEAR)&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;table cellpadding="0" cellspacing="0" style="border-collapse:collapse;border-style:none;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:51%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:21%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;Costs of a $10,000 investment&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:27%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;Costs paid as a percentage of a $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:51%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;Class C&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:21%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;152&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:27%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;1.52&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:ExpensesTextBlock>
    <oef:ExpensesPaidAmt
      contextRef="C000019123_ClassMember"
      decimals="0"
      id="ixv-353815"
      unitRef="usd">152</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000019123_ClassMember"
      decimals="INF"
      id="ixv-353816"
      unitRef="pure">0.0152</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000019123_ClassMember" id="ixv-1318">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What affected the Fund's performance this period?&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;U.S. taxable investment-grade bonds achieved a gain for the 12 months ending August 31, 2026, buoyed by three policy interest-rate cuts by the Federal Reserve in late 2025, but pulled down since then by rising bond yields amid higher consumer inflation, a resilient economy and heavy U.S. Treasury issuance.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Against this backdrop, the fund's top contributors relative to its benchmark, the Bloomberg U.S. Aggregate Bond Index, for the fiscal year came from overweight allocations to securitized products - specifically, outperforming stakes in asset-backed securities, including AAA-rated collateralized loan obligations, and commercial mortgage-backed securities.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Converserly, the fund's yield-curve positioning and its modestly longer-than-benchmark duration in a rising-rate environment modestly detracted.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;An underweight in agency mortgage-backed securities also modestly hindered performance.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;In terms of security selection, picks in corporate debt, sovereign government bonds and commercial mortgage-backed securities helped.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;The fund's managers did not make significant adjustments in positioning over the period and sought to keep the fund conservatively positioned versus the benchmark.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:FactorsAffectingPerfTextBlock>
    <oef:LineGraphTableTextBlock contextRef="C000019123_ClassMember" id="ixv-1342">How did the Fund perform over the past 10 years?

 &#160;&#160;
CUMULATIVE PERFORMANCE
August 31, 2016 through August 31, 2026. 
Initial investment of $10,000.
Class C


$10,000

$10,027


$9,814


$10,723


$11,522


$11,536


$10,085


$9,913


$10,575


$10,891


$11,041



Bloomberg U.S. Aggregate Bond Index


$10,000

$10,049


$9,944


$10,955


$11,665


$11,655


$10,313


$10,189


$10,933


$11,276


$11,489



&#160;

2016

2017

2018

2019

2020

2021

2022

2023

2024

2025

2026









&#160;
</oef:LineGraphTableTextBlock>
    <oef:LineGraphAndTableMeasureName contextRef="C000019123_LG_ClassMember_11YR" id="ixv-1361">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Class C&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000019123_ClassMember_AsOf_2016"
      decimals="0"
      id="ixv-353817"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019123_ClassMember_AsOf_2017"
      decimals="0"
      id="ixv-353818"
      unitRef="usd">10027</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019123_ClassMember_AsOf_2018"
      decimals="0"
      id="ixv-353819"
      unitRef="usd">9814</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019123_ClassMember_AsOf_2019"
      decimals="0"
      id="ixv-353820"
      unitRef="usd">10723</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019123_ClassMember_AsOf_2020"
      decimals="0"
      id="ixv-353821"
      unitRef="usd">11522</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019123_ClassMember_AsOf_2021"
      decimals="0"
      id="ixv-353822"
      unitRef="usd">11536</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019123_ClassMember_AsOf_2022"
      decimals="0"
      id="ixv-353823"
      unitRef="usd">10085</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019123_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-353824"
      unitRef="usd">9913</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019123_ClassMember_AsOf_2024"
      decimals="0"
      id="ixv-353825"
      unitRef="usd">10575</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019123_ClassMember_AsOf_2025"
      decimals="0"
      id="ixv-353826"
      unitRef="usd">10891</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019123_ClassMember_AsOf_2026"
      decimals="0"
      id="ixv-353827"
      unitRef="usd">11041</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000019123_LG_1_AdditionalIndexMember_11YR"
      id="ixv-1410">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg U.S. Aggregate Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000019123_1_AdditionalIndexMember_AsOf_2016"
      decimals="0"
      id="ixv-353828"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019123_1_AdditionalIndexMember_AsOf_2017"
      decimals="0"
      id="ixv-353829"
      unitRef="usd">10049</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019123_1_AdditionalIndexMember_AsOf_2018"
      decimals="0"
      id="ixv-353830"
      unitRef="usd">9944</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019123_1_AdditionalIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-353831"
      unitRef="usd">10955</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019123_1_AdditionalIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-353832"
      unitRef="usd">11665</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019123_1_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-353833"
      unitRef="usd">11655</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019123_1_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-353834"
      unitRef="usd">10313</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019123_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-353835"
      unitRef="usd">10189</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019123_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-353836"
      unitRef="usd">10933</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019123_1_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-353837"
      unitRef="usd">11276</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019123_1_AdditionalIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-353838"
      unitRef="usd">11489</oef:AccmVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000019123_ClassMember" id="ixv-1511">AVERAGE ANNUAL TOTAL RETURNS:

&#160;

1 Year

5 Year

10 Year


Class C &#160;(incl. contingent deferred sales charge)

-0.37%

-1.17%


1.00%


Class C

0.60%

-1.17%

1.00%


Bloomberg U.S. Aggregate Bond Index

1.89%


-0.29%


1.40%




&#160;
&#160;
Visit institutional.fidelity.com for more recent performance information.&#160;

&#160;


The Fund's past performance is not a good predictor of the Fund's future performance. &#160;The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.





</oef:AvgAnnlRtrTableTextBlock>
    <oef:AvgAnnlRtrPct
      contextRef="C000019123_ClassMember_1YR"
      decimals="INF"
      id="ixv-353839"
      unitRef="pure">-0.0037</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019123_ClassMember_5YR"
      decimals="INF"
      id="ixv-353840"
      unitRef="pure">-0.0117</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019123_ClassMember_10YR"
      decimals="INF"
      id="ixv-353841"
      unitRef="pure">0.0100</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019123_NoLoadClassMember_1YR"
      decimals="INF"
      id="ixv-353842"
      unitRef="pure">0.0060</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019123_NoLoadClassMember_5YR"
      decimals="INF"
      id="ixv-353843"
      unitRef="pure">-0.0117</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019123_NoLoadClassMember_10YR"
      decimals="INF"
      id="ixv-353844"
      unitRef="pure">0.0100</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019123_0_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-353845"
      unitRef="pure">0.0189</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019123_0_BBIndexMember_5YR"
      decimals="INF"
      id="ixv-353846"
      unitRef="pure">-0.0029</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019123_0_BBIndexMember_10YR"
      decimals="INF"
      id="ixv-353847"
      unitRef="pure">0.0140</oef:AvgAnnlRtrPct>
    <oef:UpdPerfInfoLocationTextBlock contextRef="C000019123_ClassMember" id="ixv-1586">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Visit &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;institutional.fidelity.com&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt; for more recent performance information.&lt;/span&gt;</oef:UpdPerfInfoLocationTextBlock>
    <oef:PerformancePastDoesNotIndicateFuture contextRef="C000019123_ClassMember" id="ixv-1598">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:italic;font-weight:normal;"&gt;The Fund's past performance is not a good predictor of the Fund's future performance.&lt;/span&gt;</oef:PerformancePastDoesNotIndicateFuture>
    <oef:NoDeductionOfTaxesTextBlock contextRef="C000019123_ClassMember" id="ixv-1602">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.&lt;/span&gt;</oef:NoDeductionOfTaxesTextBlock>
    <oef:AddlFundStatisticsTextBlock contextRef="C000019123_ClassMember" id="ixv-1608">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;Key Fund Statistics&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(as of August 31, 2026)&lt;/span&gt;&lt;/div&gt;
&lt;div&gt;&lt;span style="font-size:11px;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;table cellpadding="0" cellspacing="1" style="border-collapse:separate;border-style:none;margin:auto;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:63%; " valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:bold;"&gt;KEY FACTS&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt; &lt;span&gt;&#160;&lt;/span&gt;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fund Size&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;11,833,010,166&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;4,328&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;32,938,746&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="middle"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Portfolio Turnover&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;142&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:AddlFundStatisticsTextBlock>
    <us-gaap:AssetsNet
      contextRef="C000019123_InstantMember"
      decimals="0"
      id="ixv-353848"
      unitRef="usd">11833010166</us-gaap:AssetsNet>
    <oef:HoldingsCount
      contextRef="C000019123_InstantMember"
      decimals="INF"
      id="ixv-353849"
      unitRef="holding">4328</oef:HoldingsCount>
    <oef:AdvisoryFeesPaidAmt
      contextRef="C000019123_ClassMember"
      decimals="0"
      id="ixv-353850"
      unitRef="usd">32938746</oef:AdvisoryFeesPaidAmt>
    <us-gaap:InvestmentCompanyPortfolioTurnover
      contextRef="C000019123_ClassMember"
      decimals="INF"
      id="ixv-353851"
      unitRef="pure">1.42</us-gaap:InvestmentCompanyPortfolioTurnover>
    <oef:HoldingsTableTextBlock contextRef="C000019123_ClassMember" id="ixv-1687">
&#160;
U.S. Government and U.S. Government Agency Obligations

61.0


AAA

5.5


AA

0.9


A

7.7


BBB

15.4


BB

2.9


B

0.8


CCC,CC,C

0.0


Not Rated

9.3




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

U.S. Government and U.S. Government Agency Obligations - 61.0


&#160;

AAA - 5.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

AA - 0.9&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

A - 7.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BBB - 15.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BB - 2.9&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

B - 0.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

CCC,CC,C - 0.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Not Rated - 9.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


Short-Term Investments and Net Other Assets (Liabilities) - (3.5)% 


&#160;


We have used ratings from Moody's Investors Service, Inc. Where Moody's&#xae; ratings are not available, we have used S&amp;P&#xae; ratings. All ratings are as of the date indicated and do not reflect subsequent changes.




&#160;
&#160;
&#160;
&#160;
U.S. Treasury Obligations

44.6


Corporate Bonds

24.3


U.S. Government Agency - Mortgage Securities

16.4


Asset-Backed Securities

9.2


CMOs and Other Mortgage Related Securities

8.7


Preferred Securities

0.2


Other Investments

0.1


Bank Loan Obligations

0.0


Options

0.0




ASSET ALLOCATION (% of Fund's net assets)


&#160;



&#160;

U.S. Treasury Obligations - 44.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Corporate Bonds - 24.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

U.S. Government Agency - Mortgage Securities - 16.4


&#160;

Asset-Backed Securities - 9.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

CMOs and Other Mortgage Related Securities - 8.7


&#160;

Preferred Securities - 0.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Other Investments - 0.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Bank Loan Obligations - 0.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Options - 0.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


Short-Term Investments and Net Other Assets (Liabilities) - (3.5)%


&#160;






United States

91.4


Grand Cayman (UK Overseas Ter)

4.4


Mexico

0.7


Bailiwick Of Jersey

0.7


Ireland

0.6


United Kingdom

0.5


Germany

0.3


Switzerland

0.3


Japan

0.2


Others

0.9




GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

United States - 91.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Grand Cayman (UK Overseas Ter) - 4.4&#160;&#160;&#160;&#160;


&#160;

Mexico - 0.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Bailiwick Of Jersey - 0.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Ireland - 0.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

United Kingdom - 0.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Germany - 0.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Switzerland - 0.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Japan - 0.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Others - 0.9&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;




&#160;




&#160;
&#160;
</oef:HoldingsTableTextBlock>
    <oef:PctOfNav
      contextRef="C000019123_QD_USGovernmentandUSGovernmentAgencyObligations_Member"
      decimals="INF"
      id="ixv-353852"
      unitRef="pure">0.610</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019123_QD_AAA_Member"
      decimals="INF"
      id="ixv-353853"
      unitRef="pure">0.055</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019123_QD_AA_Member"
      decimals="INF"
      id="ixv-353854"
      unitRef="pure">0.009</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019123_QD_A_Member"
      decimals="INF"
      id="ixv-353855"
      unitRef="pure">0.077</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019123_QD_BBB_Member"
      decimals="INF"
      id="ixv-353856"
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      id="ixv-353864"
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      contextRef="C000019123_AA_CMOsandOtherMortgageRelatedSecurities_Member"
      decimals="INF"
      id="ixv-353865"
      unitRef="pure">0.087</oef:PctOfNav>
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      decimals="INF"
      id="ixv-353866"
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      id="ixv-353867"
      unitRef="pure">0.001</oef:PctOfNav>
    <oef:PctOfNav
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    <oef:PctOfNav
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      decimals="INF"
      id="ixv-353870"
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    <oef:PctOfNav
      contextRef="C000019123_GD_GrandCaymanUKOverseasTer_Member"
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      id="ixv-353871"
      unitRef="pure">0.044</oef:PctOfNav>
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      decimals="INF"
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      unitRef="pure">0.003</oef:PctOfNav>
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      unitRef="pure">0.002</oef:PctOfNav>
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      decimals="INF"
      id="ixv-353879"
      unitRef="pure">0.009</oef:PctOfNav>
    <oef:LargestHoldingsTableTextBlock contextRef="C000019123_ClassMember" id="ixv-2156">TOP HOLDINGS(% of Fund's net assets)

&#160;

&#160;


US Treasury Notes

34.3


&#160;


US Treasury Bonds

10.3


&#160;


Fannie Mae Mortgage pass-thru certificates

5.3


&#160;


Freddie Mac Gold Pool

4.4


&#160;


Ginnie Mae II Pool

3.8


&#160;


Uniform Mortgage Backed Securities

2.4


&#160;


Freddie Mac Multifamily Structured pass-thru certificates

2.2


&#160;


Citigroup Inc

1.2


&#160;


Bank of America Corp

1.1


&#160;


JPMorgan Chase &amp; Co

0.9


&#160;


&#160;

65.9

&#160;



</oef:LargestHoldingsTableTextBlock>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-353880"
      unitRef="pure">0.343</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-353881"
      unitRef="pure">0.103</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019123_TH_2_Member"
      decimals="INF"
      id="ixv-353882"
      unitRef="pure">0.053</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-353883"
      unitRef="pure">0.044</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019123_TH_4_Member"
      decimals="INF"
      id="ixv-353884"
      unitRef="pure">0.038</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019123_TH_5_Member"
      decimals="INF"
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      unitRef="pure">0.024</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
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      unitRef="pure">0.022</oef:PctOfNav>
    <oef:PctOfNav
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      unitRef="pure">0.012</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019123_TH_8_Member"
      decimals="INF"
      id="ixv-353888"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019123_TH_9_Member"
      decimals="INF"
      id="ixv-353889"
      unitRef="pure">0.009</oef:PctOfNav>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-2327">2026-08-31</dei:DocumentPeriodEndDate>
    <oef:FundName contextRef="C000171439_ClassMember" id="ixv-2339">Fidelity&#xae; Short-Term Bond Fund</oef:FundName>
    <oef:ClassName contextRef="C000171439_ClassMember" id="ixv-2342">Fidelity Advisor&#xae; Short-Term Bond Fund Class C</oef:ClassName>
    <dei:TradingSymbol contextRef="C000171439_ClassMember" id="ixv-2346">FANCX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000171439_ClassMember" id="ixv-2365">This annual shareholder report contains information about Fidelity&#xae; Short-Term Bond Fund for the period September 1, 2025 to August 31, 2026.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000171439_ClassMember" id="ixv-2367">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000171439_ClassMember" id="ixv-2372">You can find additional information about the Fund at fundresearch.fidelity.com/prospectus/sec. You can also request this information by contacting us at 1-877-208-0098 or by sending an e-mail to fidfunddocuments@fidelity.com.</oef:AddlInfoTextBlock>
    <oef:AddlInfoWebsite contextRef="C000171439_ClassMember" id="ixv-2374">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000171439_ClassMember" id="ixv-2377">1-877-208-0098</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000171439_ClassMember" id="ixv-2380">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000171439_ClassMember" id="ixv-2387">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What were your Fund costs for the last year?&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(based on hypothetical $10,000 investment)&lt;/span&gt;&lt;/div&gt;
&lt;div&gt;&lt;span style="font-size:11px;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:bold;"&gt;FUND COST (PREVIOUS YEAR)&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;table cellpadding="0" cellspacing="0" style="border-collapse:collapse;border-style:none;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:51%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:21%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;Costs of a $10,000 investment&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:27%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;Costs paid as a percentage of a $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:51%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;Class C&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:21%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;137&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:27%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;1.36&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:ExpensesTextBlock>
    <oef:ExpensesPaidAmt
      contextRef="C000171439_ClassMember"
      decimals="0"
      id="ixv-353890"
      unitRef="usd">137</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000171439_ClassMember"
      decimals="INF"
      id="ixv-353891"
      unitRef="pure">0.0136</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000171439_ClassMember" id="ixv-2430">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What affected the Fund's performance this period?&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;U.S. taxable investment-grade bonds achieved a gain for the 12 months ending August 31, 2026, buoyed by three policy interest-rate cuts by the Federal Reserve in late 2025, but pulled down since then by rising bond yields amid higher consumer inflation, a resilient economy and heavy U.S. Treasury issuance.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Against this backdrop, the fund's strategy of favoring short-term corporate bonds, while underweighting similar-duration U.S. Treasurys, contributed to its performance versus the benchmark Bloomberg U.S. 1-3 Year Government/Credit Bond Index for the fiscal year. Within corporates, debt holdings among financial institutions, especially banks, added notable value.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Non-benchmark exposure to asset-backed securities, including car loan debt and collateralized loan obligations, also meaningfully helped.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;In contrast, the fund's yield-curve positioning, including the underweighting of one-year maturities in favor of two- and three-year positions, detracted from relative performance.&#160;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;At fiscal year-end, corporates made up about 40% of fund assets, down from 41% a year ago but still notably overweight versus the benchmark average of 22%. Exposure to U.S. Treasurys stood at roughly 43% at the end of the period, up from 35% a year ago and compared with an average of about 72% for the 1-3 year benchmark. Exposure to ABS fell from roughly 18% of assets to about 12% as of August 31.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:FactorsAffectingPerfTextBlock>
    <oef:LineGraphTableTextBlock contextRef="C000171439_ClassMember" id="ixv-2451">How did the Fund perform over the past 10 years?

 &#160;&#160;
CUMULATIVE PERFORMANCE
August 31, 2016 through August 31, 2026. 
Initial investment of $10,000.
Class C


$10,000

$10,002


$9,916


$10,250


$10,529


$10,468


$9,927


$10,049


$10,601


$11,098


$11,361



Bloomberg U.S. 1-3 Year Government/Credit Bond Index


$10,000

$10,090


$10,106


$10,572


$10,960


$11,003


$10,565


$10,730


$11,401


$11,930


$12,251



Bloomberg U.S. Aggregate Bond Index


$10,000

$10,049


$9,944


$10,955


$11,665


$11,655


$10,313


$10,189


$10,933


$11,276


$11,489



&#160;

2016

2017

2018

2019

2020

2021

2022

2023

2024

2025

2026









&#160;
</oef:LineGraphTableTextBlock>
    <oef:LineGraphAndTableMeasureName contextRef="C000171439_LG_ClassMember_11YR" id="ixv-2470">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Class C&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000171439_ClassMember_AsOf_2016"
      decimals="0"
      id="ixv-353892"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171439_ClassMember_AsOf_2017"
      decimals="0"
      id="ixv-353893"
      unitRef="usd">10002</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171439_ClassMember_AsOf_2018"
      decimals="0"
      id="ixv-353894"
      unitRef="usd">9916</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171439_ClassMember_AsOf_2019"
      decimals="0"
      id="ixv-353895"
      unitRef="usd">10250</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171439_ClassMember_AsOf_2020"
      decimals="0"
      id="ixv-353896"
      unitRef="usd">10529</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171439_ClassMember_AsOf_2021"
      decimals="0"
      id="ixv-353897"
      unitRef="usd">10468</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171439_ClassMember_AsOf_2022"
      decimals="0"
      id="ixv-353898"
      unitRef="usd">9927</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171439_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-353899"
      unitRef="usd">10049</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171439_ClassMember_AsOf_2024"
      decimals="0"
      id="ixv-353900"
      unitRef="usd">10601</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171439_ClassMember_AsOf_2025"
      decimals="0"
      id="ixv-353901"
      unitRef="usd">11098</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171439_ClassMember_AsOf_2026"
      decimals="0"
      id="ixv-353902"
      unitRef="usd">11361</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000171439_LG_1_AdditionalIndexMember_11YR"
      id="ixv-2519">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg U.S. 1-3 Year Government/Credit Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000171439_1_AdditionalIndexMember_AsOf_2016"
      decimals="0"
      id="ixv-353903"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171439_1_AdditionalIndexMember_AsOf_2017"
      decimals="0"
      id="ixv-353904"
      unitRef="usd">10090</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171439_1_AdditionalIndexMember_AsOf_2018"
      decimals="0"
      id="ixv-353905"
      unitRef="usd">10106</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171439_1_AdditionalIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-353906"
      unitRef="usd">10572</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171439_1_AdditionalIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-353907"
      unitRef="usd">10960</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171439_1_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-353908"
      unitRef="usd">11003</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171439_1_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-353909"
      unitRef="usd">10565</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171439_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-353910"
      unitRef="usd">10730</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171439_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-353911"
      unitRef="usd">11401</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171439_1_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-353912"
      unitRef="usd">11930</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171439_1_AdditionalIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-353913"
      unitRef="usd">12251</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000171439_LG_2_AdditionalIndexMember_11YR"
      id="ixv-2568">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg U.S. Aggregate Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000171439_2_AdditionalIndexMember_AsOf_2016"
      decimals="0"
      id="ixv-353914"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171439_2_AdditionalIndexMember_AsOf_2017"
      decimals="0"
      id="ixv-353915"
      unitRef="usd">10049</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171439_2_AdditionalIndexMember_AsOf_2018"
      decimals="0"
      id="ixv-353916"
      unitRef="usd">9944</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171439_2_AdditionalIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-353917"
      unitRef="usd">10955</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171439_2_AdditionalIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-353918"
      unitRef="usd">11665</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171439_2_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-353919"
      unitRef="usd">11655</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171439_2_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-353920"
      unitRef="usd">10313</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171439_2_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-353921"
      unitRef="usd">10189</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171439_2_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-353922"
      unitRef="usd">10933</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171439_2_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-353923"
      unitRef="usd">11276</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171439_2_AdditionalIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-353924"
      unitRef="usd">11489</oef:AccmVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000171439_ClassMember" id="ixv-2669">AVERAGE ANNUAL TOTAL RETURNS:

&#160;

1 Year

5 Year

10 Year


Class C &#160;(incl. contingent deferred sales charge)

0.50%

1.30%


1.28%


Class C

1.49%

1.30%

1.28%


Bloomberg U.S. 1-3 Year Government/Credit Bond Index

2.69%


2.17%


2.05%


Bloomberg U.S. Aggregate Bond Index

1.89%


-0.29%


1.40%




&#160;
&#160;
Visit institutional.fidelity.com for more recent performance information.&#160;

&#160;


The Fund's past performance is not a good predictor of the Fund's future performance. &#160;The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.





</oef:AvgAnnlRtrTableTextBlock>
    <oef:AvgAnnlRtrPct
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      decimals="INF"
      id="ixv-353925"
      unitRef="pure">0.0050</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000171439_ClassMember_5YR"
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      id="ixv-353926"
      unitRef="pure">0.0130</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000171439_ClassMember_10YR"
      decimals="INF"
      id="ixv-353927"
      unitRef="pure">0.0128</oef:AvgAnnlRtrPct>
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      decimals="INF"
      id="ixv-353928"
      unitRef="pure">0.0149</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
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      decimals="INF"
      id="ixv-353929"
      unitRef="pure">0.0130</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000171439_NoLoadClassMember_10YR"
      decimals="INF"
      id="ixv-353930"
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    <oef:AvgAnnlRtrPct
      contextRef="C000171439_0_AdditionalIndexMember_1YR"
      decimals="INF"
      id="ixv-353931"
      unitRef="pure">0.0269</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000171439_0_AdditionalIndexMember_5YR"
      decimals="INF"
      id="ixv-353932"
      unitRef="pure">0.0217</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
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      decimals="INF"
      id="ixv-353933"
      unitRef="pure">0.0205</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000171439_1_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-353934"
      unitRef="pure">0.0189</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000171439_1_BBIndexMember_5YR"
      decimals="INF"
      id="ixv-353935"
      unitRef="pure">-0.0029</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000171439_1_BBIndexMember_10YR"
      decimals="INF"
      id="ixv-353936"
      unitRef="pure">0.0140</oef:AvgAnnlRtrPct>
    <oef:UpdPerfInfoLocationTextBlock contextRef="C000171439_ClassMember" id="ixv-2756">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Visit &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;institutional.fidelity.com&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt; for more recent performance information.&lt;/span&gt;</oef:UpdPerfInfoLocationTextBlock>
    <oef:PerformancePastDoesNotIndicateFuture contextRef="C000171439_ClassMember" id="ixv-2768">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:italic;font-weight:normal;"&gt;The Fund's past performance is not a good predictor of the Fund's future performance.&lt;/span&gt;</oef:PerformancePastDoesNotIndicateFuture>
    <oef:NoDeductionOfTaxesTextBlock contextRef="C000171439_ClassMember" id="ixv-2772">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.&lt;/span&gt;</oef:NoDeductionOfTaxesTextBlock>
    <oef:AddlFundStatisticsTextBlock contextRef="C000171439_ClassMember" id="ixv-2778">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;Key Fund Statistics&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(as of August 31, 2026)&lt;/span&gt;&lt;/div&gt;
&lt;div&gt;&lt;span style="font-size:11px;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;table cellpadding="0" cellspacing="1" style="border-collapse:separate;border-style:none;margin:auto;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:63%; " valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:bold;"&gt;KEY FACTS&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt; &lt;span&gt;&#160;&lt;/span&gt;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fund Size&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;2,843,357,688&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;483&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;5,198,445&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="middle"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Portfolio Turnover&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;95&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:AddlFundStatisticsTextBlock>
    <us-gaap:AssetsNet
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      unitRef="usd">2843357688</us-gaap:AssetsNet>
    <oef:HoldingsCount
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      unitRef="holding">483</oef:HoldingsCount>
    <oef:AdvisoryFeesPaidAmt
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    <oef:HoldingsTableTextBlock contextRef="C000171439_ClassMember" id="ixv-2853">
&#160;
U.S. Government and U.S. Government Agency Obligations

43.3


AAA

9.9


AA

1.2


A

21.3


BBB

16.6


BB

1.4


Not Rated

5.8


Short-Term Investments and Net Other Assets (Liabilities)

0.5




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

U.S. Government and U.S. Government Agency Obligations - 43.3


&#160;

AAA - 9.9&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

AA - 1.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

A - 21.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BBB - 16.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BB - 1.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Not Rated - 5.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Short-Term Investments and Net Other Assets (Liabilities) - 0.5


&#160;


We have used ratings from Moody's Investors Service, Inc. Where Moody's&#xae; ratings are not available, we have used S&amp;P&#xae; ratings. All ratings are as of the date indicated and do not reflect subsequent changes.




&#160;
&#160;
&#160;
&#160;
U.S. Treasury Obligations

43.1


Corporate Bonds

39.1


Asset-Backed Securities

12.3


CMOs and Other Mortgage Related Securities

4.2


Other Investments

0.4


U.S. Government Agency - Mortgage Securities

0.2


Foreign Government and Government Agency Obligations

0.2


Short-Term Investments and Net Other Assets (Liabilities)

0.5




ASSET ALLOCATION (% of Fund's net assets)


&#160;



&#160;

U.S. Treasury Obligations - 43.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Corporate Bonds - 39.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Asset-Backed Securities - 12.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

CMOs and Other Mortgage Related Securities - 4.2


&#160;

Other Investments - 0.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

U.S. Government Agency - Mortgage Securities - 0.2


&#160;

Foreign Government and Government Agency Obligations - 0.2


&#160;

Short-Term Investments and Net Other Assets (Liabilities) - 0.5


&#160;






United States

78.6


Grand Cayman (UK Overseas Ter)

4.3


United Kingdom

3.6


Canada

2.8


Germany

2.7


France

1.4


Bailiwick Of Jersey

1.2


Ireland

1.1


Japan

1.0


Others

3.3




GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

United States - 78.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Grand Cayman (UK Overseas Ter) - 4.3&#160;&#160;&#160;&#160;


&#160;

United Kingdom - 3.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Canada - 2.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Germany - 2.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

France - 1.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Bailiwick Of Jersey - 1.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Ireland - 1.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Japan - 1.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Others - 3.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;




&#160;




&#160;
&#160;
</oef:HoldingsTableTextBlock>
    <oef:PctOfNav
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    <oef:PctOfNav
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    <oef:PctOfNav
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      decimals="INF"
      id="ixv-353951"
      unitRef="pure">0.123</oef:PctOfNav>
    <oef:PctOfNav
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      id="ixv-353952"
      unitRef="pure">0.042</oef:PctOfNav>
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      id="ixv-353953"
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    <oef:PctOfNav
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      id="ixv-353954"
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    <oef:PctOfNav
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      decimals="INF"
      id="ixv-353955"
      unitRef="pure">0.002</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000171439_AA_ShortTermInvestmentsandNetOtherAssetsLiabilities_Member"
      decimals="INF"
      id="ixv-353956"
      unitRef="pure">0.005</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000171439_GD_US_Member"
      decimals="INF"
      id="ixv-353957"
      unitRef="pure">0.786</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000171439_GD_GrandCaymanUKOverseasTer_Member"
      decimals="INF"
      id="ixv-353958"
      unitRef="pure">0.043</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000171439_GD_GB_Member"
      decimals="INF"
      id="ixv-353959"
      unitRef="pure">0.036</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000171439_GD_CA_Member"
      decimals="INF"
      id="ixv-353960"
      unitRef="pure">0.028</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000171439_GD_DE_Member"
      decimals="INF"
      id="ixv-353961"
      unitRef="pure">0.027</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000171439_GD_FR_Member"
      decimals="INF"
      id="ixv-353962"
      unitRef="pure">0.014</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000171439_GD_BailiwickOfJersey_Member"
      decimals="INF"
      id="ixv-353963"
      unitRef="pure">0.012</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000171439_GD_IE_Member"
      decimals="INF"
      id="ixv-353964"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000171439_GD_JP_Member"
      decimals="INF"
      id="ixv-353965"
      unitRef="pure">0.010</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000171439_GD_Other_Member"
      decimals="INF"
      id="ixv-353966"
      unitRef="pure">0.033</oef:PctOfNav>
    <oef:LargestHoldingsTableTextBlock contextRef="C000171439_ClassMember" id="ixv-3288">TOP HOLDINGS(% of Fund's net assets)

&#160;

&#160;


US Treasury Notes

43.1


&#160;


Bank of America Corp

1.4


&#160;


JPMorgan Chase &amp; Co

1.3


&#160;


Wells Fargo &amp; Co

1.2


&#160;


Goldman Sachs Group Inc/The

1.0


&#160;


Citigroup Inc

0.9


&#160;


Deutsche Bank AG/New York NY

0.9


&#160;


General Motors Financial Co Inc

0.9


&#160;


Barclays PLC

0.8


&#160;


HSBC Holdings PLC

0.8


&#160;


&#160;

52.3

&#160;



</oef:LargestHoldingsTableTextBlock>
    <oef:PctOfNav
      contextRef="C000171439_TH_0_Member"
      decimals="INF"
      id="ixv-353967"
      unitRef="pure">0.431</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000171439_TH_1_Member"
      decimals="INF"
      id="ixv-353968"
      unitRef="pure">0.014</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000171439_TH_2_Member"
      decimals="INF"
      id="ixv-353969"
      unitRef="pure">0.013</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000171439_TH_3_Member"
      decimals="INF"
      id="ixv-353970"
      unitRef="pure">0.012</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000171439_TH_4_Member"
      decimals="INF"
      id="ixv-353971"
      unitRef="pure">0.010</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000171439_TH_5_Member"
      decimals="INF"
      id="ixv-353972"
      unitRef="pure">0.009</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000171439_TH_6_Member"
      decimals="INF"
      id="ixv-353973"
      unitRef="pure">0.009</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000171439_TH_7_Member"
      decimals="INF"
      id="ixv-353974"
      unitRef="pure">0.009</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000171439_TH_8_Member"
      decimals="INF"
      id="ixv-353975"
      unitRef="pure">0.008</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000171439_TH_9_Member"
      decimals="INF"
      id="ixv-353976"
      unitRef="pure">0.008</oef:PctOfNav>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-3459">2026-08-31</dei:DocumentPeriodEndDate>
    <oef:MaterialFundChngNoticeTextBlock contextRef="C000234190_ClassMember" id="ixv-3463">This report describes changes to the Fund that occurred during the reporting period.</oef:MaterialFundChngNoticeTextBlock>
    <oef:FundName contextRef="C000234190_ClassMember" id="ixv-3474">Fidelity&#xae; Tactical Bond Fund</oef:FundName>
    <oef:ClassName contextRef="C000234190_ClassMember" id="ixv-3477">Fidelity Advisor&#xae; Tactical Bond Fund Class Z</oef:ClassName>
    <dei:TradingSymbol contextRef="C000234190_ClassMember" id="ixv-3481">FBAPX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000234190_ClassMember" id="ixv-3500">This annual shareholder report contains information about Fidelity&#xae; Tactical Bond Fund for the period September 1, 2025 to August 31, 2026.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000234190_ClassMember" id="ixv-3502">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000234190_ClassMember" id="ixv-3507">You can find additional information about the Fund at fundresearch.fidelity.com/prospectus/sec. You can also request this information by contacting us at 1-877-208-0098 or by sending an e-mail to fidfunddocuments@fidelity.com.</oef:AddlInfoTextBlock>
    <oef:AddlInfoWebsite contextRef="C000234190_ClassMember" id="ixv-3509">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000234190_ClassMember" id="ixv-3512">1-877-208-0098</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000234190_ClassMember" id="ixv-3515">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000234190_ClassMember" id="ixv-3522">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What were your Fund costs for the last year?&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(based on hypothetical $10,000 investment)&lt;/span&gt;&lt;/div&gt;
&lt;div&gt;&lt;span style="font-size:11px;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:bold;"&gt;FUND COST (PREVIOUS YEAR)&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;table cellpadding="0" cellspacing="0" style="border-collapse:collapse;border-style:none;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:51%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:21%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;Costs of a $10,000 investment&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:27%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;Costs paid as a percentage of a $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:51%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;Class Z&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:21%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;61&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:27%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;0.61&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:ExpensesTextBlock>
    <oef:ExpensesPaidAmt
      contextRef="C000234190_ClassMember"
      decimals="0"
      id="ixv-353977"
      unitRef="usd">61</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000234190_ClassMember"
      decimals="INF"
      id="ixv-353978"
      unitRef="pure">0.0061</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000234190_ClassMember" id="ixv-3565">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What affected the Fund's performance this period?&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;U.S. taxable investment-grade bonds achieved a gain for the 12 months ending August 31, 2026, buoyed by three policy interest-rate cuts by the Federal Reserve in late 2025, but pulled down since then by rising bond yields amid higher consumer inflation, a resilient economy and heavy U.S. Treasury issuance.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Against this backdrop, the fund's top contributors relative to its benchmark, the Bloomberg U.S. Aggregate Bond Index, for the fiscal year came from out-of-benchmark allocations to outperforming high-yield bonds, global bonds and emerging-markets debt.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Converserly, the ETF's yield-curve positioning and its longer-than-benchmark duration in a rising-rate environment detracted from performance versus the benchmark.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;An underweight in agency mortgage-backed securities also modestly hurt.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Notable changes in positioning include increased exposure to U.S. Treasurys and reduced exposure to high-yield bonds.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:FactorsAffectingPerfTextBlock>
    <oef:LineGraphTableTextBlock contextRef="C000234190_ClassMember" id="ixv-3586">How did the Fund perform over the life of Fund?

 &#160;&#160;
CUMULATIVE PERFORMANCE
February 10, 2022 through August 31, 2026. 
Initial investment of $10,000.
Class Z


$10,000

$9,275


$9,330


$10,072


$10,424



Bloomberg U.S. Aggregate Bond Index


$10,000

$9,301


$9,190


$9,861


$10,170



&#160;

2022

2023

2024

2025

2026









&#160;
</oef:LineGraphTableTextBlock>
    <oef:LineGraphAndTableMeasureName contextRef="C000234190_LG_ClassMember_5YR" id="ixv-3605">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Class Z&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000234190_ClassMember_AsOf_2022"
      decimals="0"
      id="ixv-353979"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000234190_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-353980"
      unitRef="usd">9275</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000234190_ClassMember_AsOf_2024"
      decimals="0"
      id="ixv-353981"
      unitRef="usd">9330</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000234190_ClassMember_AsOf_2025"
      decimals="0"
      id="ixv-353982"
      unitRef="usd">10072</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000234190_ClassMember_AsOf_2026"
      decimals="0"
      id="ixv-353983"
      unitRef="usd">10424</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000234190_LG_1_AdditionalIndexMember_5YR"
      id="ixv-3630">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg U.S. Aggregate Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000234190_1_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-353984"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000234190_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-353985"
      unitRef="usd">9301</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000234190_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-353986"
      unitRef="usd">9190</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000234190_1_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-353987"
      unitRef="usd">9861</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000234190_1_AdditionalIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-353988"
      unitRef="usd">10170</oef:AccmVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000234190_ClassMember" id="ixv-3689">AVERAGE ANNUAL TOTAL RETURNS:

&#160;

1 Year

Life of Fund&#160;A


Class Z

2.60%

1.49%


Bloomberg U.S. Aggregate Bond Index

1.89%


0.78%




A&#160; &#160;From February 10, 2022

&#160;
Visit institutional.fidelity.com for more recent performance information.&#160;

&#160;


The Fund's past performance is not a good predictor of the Fund's future performance. &#160;The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.





</oef:AvgAnnlRtrTableTextBlock>
    <oef:AvgAnnlRtrPct
      contextRef="C000234190_NoLoadClassMember_1YR"
      decimals="INF"
      id="ixv-353989"
      unitRef="pure">0.0260</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000234190_NoLoadClassMember_2025-09-01_2026-08-31"
      decimals="INF"
      id="ixv-353990"
      unitRef="pure">0.0149</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000234190_0_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-353991"
      unitRef="pure">0.0189</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000234190_0_BBIndexMember_LOC"
      decimals="INF"
      id="ixv-353992"
      unitRef="pure">0.0078</oef:AvgAnnlRtrPct>
    <oef:PerfInceptionDate
      contextRef="C000234190_Perf_2022-02-10_ClassMember"
      id="ixv-3733">2022-02-10</oef:PerfInceptionDate>
    <oef:UpdPerfInfoLocationTextBlock contextRef="C000234190_ClassMember" id="ixv-3743">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Visit &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;institutional.fidelity.com&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt; for more recent performance information.&lt;/span&gt;</oef:UpdPerfInfoLocationTextBlock>
    <oef:PerformancePastDoesNotIndicateFuture contextRef="C000234190_ClassMember" id="ixv-3755">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:italic;font-weight:normal;"&gt;The Fund's past performance is not a good predictor of the Fund's future performance.&lt;/span&gt;</oef:PerformancePastDoesNotIndicateFuture>
    <oef:NoDeductionOfTaxesTextBlock contextRef="C000234190_ClassMember" id="ixv-3759">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.&lt;/span&gt;</oef:NoDeductionOfTaxesTextBlock>
    <oef:AddlFundStatisticsTextBlock contextRef="C000234190_ClassMember" id="ixv-3765">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;Key Fund Statistics&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(as of August 31, 2026)&lt;/span&gt;&lt;/div&gt;
&lt;div&gt;&lt;span style="font-size:11px;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;table cellpadding="0" cellspacing="1" style="border-collapse:separate;border-style:none;margin:auto;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:63%; " valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:bold;"&gt;KEY FACTS&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt; &lt;span&gt;&#160;&lt;/span&gt;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fund Size&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;43,942,866&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;99&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;284,923&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="middle"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Portfolio Turnover&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;28&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:AddlFundStatisticsTextBlock>
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&#160;
U.S. Government and U.S. Government Agency Obligations

46.1


AAA

1.2


AA

0.2


A

3.4


BBB

12.0


BB

12.3


B

11.9


CCC,CC,C

2.6


Not Rated

5.0


Equities

2.7


Short-Term Investments and Net Other Assets (Liabilities)

2.6




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

U.S. Government and U.S. Government Agency Obligations - 46.1


&#160;

AAA - 1.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

AA - 0.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

A - 3.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BBB - 12.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BB - 12.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

B - 11.9&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

CCC,CC,C - 2.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Not Rated - 5.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Equities - 2.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Short-Term Investments and Net Other Assets (Liabilities) - 2.6


&#160;


We have used ratings from Moody's Investors Service, Inc. Where Moody's&#xae; ratings are not available, we have used S&amp;P&#xae; ratings. All ratings are as of the date indicated and do not reflect subsequent changes.




&#160;
&#160;
&#160;
&#160;
U.S. Treasury Obligations

46.1


Corporate Bonds

24.6


Bank Loan Obligations

10.5


Asset-Backed Securities

5.4


Foreign Government and Government Agency Obligations

4.0


Fixed-Income Funds

2.0


CMOs and Other Mortgage Related Securities

2.0


Preferred Securities

1.5


Common Stocks

0.5


Alternative Funds

0.4


Municipal Securities

0.2


Preferred Stocks

0.2


Short-Term Investments and Net Other Assets (Liabilities)

2.6




ASSET ALLOCATION (% of Fund's net assets)


&#160;



&#160;

U.S. Treasury Obligations - 46.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Corporate Bonds - 24.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Bank Loan Obligations - 10.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Asset-Backed Securities - 5.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Foreign Government and Government Agency Obligations - 4.0


&#160;

Fixed-Income Funds - 2.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

CMOs and Other Mortgage Related Securities - 2.0


&#160;

Preferred Securities - 1.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Common Stocks - 0.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Alternative Funds - 0.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Municipal Securities - 0.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Preferred Stocks - 0.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Short-Term Investments and Net Other Assets (Liabilities) - 2.6


&#160;






United States

83.8


United Kingdom

2.5


Canada

1.8


Mexico

1.4


Brazil

1.3


Dominican Republic

1.1


Germany

1.1


France

1.0


Israel

0.9


Others

5.1




GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

United States - 83.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

United Kingdom - 2.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Canada - 1.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Mexico - 1.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Brazil - 1.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Dominican Republic - 1.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Germany - 1.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

France - 1.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Israel - 0.9&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Others - 5.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;




&#160;




&#160;
&#160;
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    <oef:LargestHoldingsTableTextBlock contextRef="C000234190_ClassMember" id="ixv-4383">TOP HOLDINGS(% of Fund's net assets)

&#160;

&#160;


US Treasury Notes

27.1


&#160;


US Treasury Bonds

19.0


&#160;


Fidelity Real Estate High Income Fund

2.0


&#160;


Domino's Pizza Master Issuer LLC

1.9


&#160;


Petroleos Mexicanos

1.4


&#160;


Dominican Republic

1.1


&#160;


Brazilian Federative Republic

1.0


&#160;


Planet Fitness Master Issuer LLC

1.0


&#160;


Charter Communications Operating LLC / Charter Communications Operating Capital

0.9


&#160;


Millicom International Cellular SA

0.8


&#160;


&#160;

56.2

&#160;



</oef:LargestHoldingsTableTextBlock>
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&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;How has the Fund changed?&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;This is a summary of certain changes to the Fund since September 1, 2025. For more complete information, you may review the Fund's next prospectus, which we expect to be available by October 30, 2026 at &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;fundresearch.fidelity.com/prospectus/sec&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt; or upon request at &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;1-877-208-0098&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:0px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt; or by sending an e-mail to &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;fidfunddocuments@fidelity.com&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;table cellpadding="0" cellspacing="0" style="border-collapse:collapse;border-style:none;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:50%; background-color:#ebf3e9;border-right:2px dashed #368627;padding:19px 19px 19px 19px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;The fund added a contractual management fee waiver during the reporting period. &lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:50%; background-color:#ebf3e9;padding:19px 19px 19px 19px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:MaterialFundChngTextBlock>
    <oef:SummaryOfChngLegendTextBlock contextRef="C000234190_ClassMember" id="ixv-4514">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;This is a summary of certain changes to the Fund since September 1, 2025. For more complete information, you may review the Fund's next prospectus, which we expect to be available by October 30, 2026 at &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;fundresearch.fidelity.com/prospectus/sec&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt; or upon request at &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;1-877-208-0098&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:0px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt; or by sending an e-mail to &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;fidfunddocuments@fidelity.com&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;.&lt;/span&gt;</oef:SummaryOfChngLegendTextBlock>
    <oef:UpdProspectusWebAddress contextRef="C000234190_ClassMember" id="ixv-4516">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;fundresearch.fidelity.com/prospectus/sec&lt;/span&gt;</oef:UpdProspectusWebAddress>
    <oef:UpdProspectusPhoneNumber contextRef="C000234190_ClassMember" id="ixv-4519">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;1-877-208-0098&lt;/span&gt;</oef:UpdProspectusPhoneNumber>
    <oef:UpdProspectusEmailAddress contextRef="C000234190_ClassMember" id="ixv-4523">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;fidfunddocuments@fidelity.com&lt;/span&gt;</oef:UpdProspectusEmailAddress>
    <oef:MaterialFundChngExpensesTextBlock contextRef="C000234190_ClassMember" id="ixv-4534">
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;The fund added a contractual management fee waiver during the reporting period. &lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:MaterialFundChngExpensesTextBlock>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-4592">2026-08-31</dei:DocumentPeriodEndDate>
    <oef:MaterialFundChngNoticeTextBlock contextRef="C000234191_ClassMember" id="ixv-4596">This report describes changes to the Fund that occurred during the reporting period.</oef:MaterialFundChngNoticeTextBlock>
    <oef:FundName contextRef="C000234191_ClassMember" id="ixv-4607">Fidelity&#xae; Tactical Bond Fund</oef:FundName>
    <oef:ClassName contextRef="C000234191_ClassMember" id="ixv-4610">Fidelity Advisor&#xae; Tactical Bond Fund Class A</oef:ClassName>
    <dei:TradingSymbol contextRef="C000234191_ClassMember" id="ixv-4614">FTKAX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000234191_ClassMember" id="ixv-4633">This annual shareholder report contains information about Fidelity&#xae; Tactical Bond Fund for the period September 1, 2025 to August 31, 2026.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000234191_ClassMember" id="ixv-4635">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000234191_ClassMember" id="ixv-4640">You can find additional information about the Fund at fundresearch.fidelity.com/prospectus/sec. You can also request this information by contacting us at 1-877-208-0098 or by sending an e-mail to fidfunddocuments@fidelity.com.</oef:AddlInfoTextBlock>
    <oef:AddlInfoWebsite contextRef="C000234191_ClassMember" id="ixv-4642">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000234191_ClassMember" id="ixv-4645">1-877-208-0098</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000234191_ClassMember" id="ixv-4648">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000234191_ClassMember" id="ixv-4655">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What were your Fund costs for the last year?&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(based on hypothetical $10,000 investment)&lt;/span&gt;&lt;/div&gt;
&lt;div&gt;&lt;span style="font-size:11px;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:bold;"&gt;FUND COST (PREVIOUS YEAR)&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;table cellpadding="0" cellspacing="0" style="border-collapse:collapse;border-style:none;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:51%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:21%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;Costs of a $10,000 investment&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:27%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;Costs paid as a percentage of a $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:51%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;Class A&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:21%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;96&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:27%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;0.95&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:ExpensesTextBlock>
    <oef:ExpensesPaidAmt
      contextRef="C000234191_ClassMember"
      decimals="0"
      id="ixv-354041"
      unitRef="usd">96</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000234191_ClassMember"
      decimals="INF"
      id="ixv-354042"
      unitRef="pure">0.0095</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000234191_ClassMember" id="ixv-4698">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What affected the Fund's performance this period?&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;U.S. taxable investment-grade bonds achieved a gain for the 12 months ending August 31, 2026, buoyed by three policy interest-rate cuts by the Federal Reserve in late 2025, but pulled down since then by rising bond yields amid higher consumer inflation, a resilient economy and heavy U.S. Treasury issuance.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Against this backdrop, the fund's top contributors relative to its benchmark, the Bloomberg U.S. Aggregate Bond Index, for the fiscal year came from out-of-benchmark allocations to outperforming high-yield bonds, global bonds and emerging-markets debt.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Converserly, the ETF's yield-curve positioning and its longer-than-benchmark duration in a rising-rate environment detracted from performance versus the benchmark.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;An underweight in agency mortgage-backed securities also modestly hurt.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Notable changes in positioning include increased exposure to U.S. Treasurys and reduced exposure to high-yield bonds.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:FactorsAffectingPerfTextBlock>
    <oef:LineGraphTableTextBlock contextRef="C000234191_ClassMember" id="ixv-4719">How did the Fund perform over the life of Fund?

 &#160;&#160;
CUMULATIVE PERFORMANCE
February 10, 2022 through August 31, 2026. 
Initial investment of $10,000&#160;and the current sales charge was paid.
Class A


$9,600

$8,887


$8,910


$9,586


$9,888



Bloomberg U.S. Aggregate Bond Index


$10,000

$9,301


$9,190


$9,861


$10,170



&#160;

2022

2023

2024

2025

2026









&#160;
</oef:LineGraphTableTextBlock>
    <oef:LineGraphAndTableMeasureName contextRef="C000234191_LG_ClassMember_5YR" id="ixv-4740">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Class A&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000234191_ClassMember_AsOf_2022"
      decimals="0"
      id="ixv-354043"
      unitRef="usd">9600</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000234191_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-354044"
      unitRef="usd">8887</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000234191_ClassMember_AsOf_2024"
      decimals="0"
      id="ixv-354045"
      unitRef="usd">8910</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000234191_ClassMember_AsOf_2025"
      decimals="0"
      id="ixv-354046"
      unitRef="usd">9586</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000234191_ClassMember_AsOf_2026"
      decimals="0"
      id="ixv-354047"
      unitRef="usd">9888</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000234191_LG_1_AdditionalIndexMember_5YR"
      id="ixv-4765">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg U.S. Aggregate Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000234191_1_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-354048"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000234191_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-354049"
      unitRef="usd">9301</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000234191_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-354050"
      unitRef="usd">9190</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000234191_1_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-354051"
      unitRef="usd">9861</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000234191_1_AdditionalIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-354052"
      unitRef="usd">10170</oef:AccmVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000234191_ClassMember" id="ixv-4824">AVERAGE ANNUAL TOTAL RETURNS:

&#160;

1 Year

Life of Fund&#160;A


Class A (incl. 4.00% sales charge) &#160;

-1.84%

0.24%


Class A (without 4.00% sales charge)

2.25%

1.14%


Bloomberg U.S. Aggregate Bond Index

1.89%


0.78%




A&#160; &#160;From February 10, 2022

&#160;
Visit institutional.fidelity.com for more recent performance information.&#160;

&#160;


The Fund's past performance is not a good predictor of the Fund's future performance. &#160;The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.





</oef:AvgAnnlRtrTableTextBlock>
    <oef:AvgAnnlRtrPct
      contextRef="C000234191_ClassMember_1YR"
      decimals="INF"
      id="ixv-354053"
      unitRef="pure">-0.0184</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000234191_ClassMember_2025-09-01_2026-08-31"
      decimals="INF"
      id="ixv-354054"
      unitRef="pure">0.0024</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000234191_NoLoadClassMember_1YR"
      decimals="INF"
      id="ixv-354055"
      unitRef="pure">0.0225</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000234191_NoLoadClassMember_2025-09-01_2026-08-31"
      decimals="INF"
      id="ixv-354056"
      unitRef="pure">0.0114</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000234191_0_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-354057"
      unitRef="pure">0.0189</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000234191_0_BBIndexMember_LOC"
      decimals="INF"
      id="ixv-354058"
      unitRef="pure">0.0078</oef:AvgAnnlRtrPct>
    <oef:PerfInceptionDate
      contextRef="C000234191_Perf_2022-02-10_ClassMember"
      id="ixv-4880">2022-02-10</oef:PerfInceptionDate>
    <oef:UpdPerfInfoLocationTextBlock contextRef="C000234191_ClassMember" id="ixv-4890">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Visit &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;institutional.fidelity.com&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt; for more recent performance information.&lt;/span&gt;</oef:UpdPerfInfoLocationTextBlock>
    <oef:PerformancePastDoesNotIndicateFuture contextRef="C000234191_ClassMember" id="ixv-4902">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:italic;font-weight:normal;"&gt;The Fund's past performance is not a good predictor of the Fund's future performance.&lt;/span&gt;</oef:PerformancePastDoesNotIndicateFuture>
    <oef:NoDeductionOfTaxesTextBlock contextRef="C000234191_ClassMember" id="ixv-4906">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.&lt;/span&gt;</oef:NoDeductionOfTaxesTextBlock>
    <oef:AddlFundStatisticsTextBlock contextRef="C000234191_ClassMember" id="ixv-4912">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;Key Fund Statistics&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(as of August 31, 2026)&lt;/span&gt;&lt;/div&gt;
&lt;div&gt;&lt;span style="font-size:11px;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;table cellpadding="0" cellspacing="1" style="border-collapse:separate;border-style:none;margin:auto;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:63%; " valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:bold;"&gt;KEY FACTS&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt; &lt;span&gt;&#160;&lt;/span&gt;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fund Size&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;43,942,866&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;99&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;284,923&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="middle"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Portfolio Turnover&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;28&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:AddlFundStatisticsTextBlock>
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&#160;
U.S. Government and U.S. Government Agency Obligations

46.1


AAA

1.2


AA

0.2


A

3.4


BBB

12.0


BB

12.3


B

11.9


CCC,CC,C

2.6


Not Rated

5.0


Equities

2.7


Short-Term Investments and Net Other Assets (Liabilities)

2.6




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

U.S. Government and U.S. Government Agency Obligations - 46.1


&#160;

AAA - 1.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

AA - 0.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

A - 3.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BBB - 12.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BB - 12.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

B - 11.9&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

CCC,CC,C - 2.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Not Rated - 5.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Equities - 2.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Short-Term Investments and Net Other Assets (Liabilities) - 2.6


&#160;


We have used ratings from Moody's Investors Service, Inc. Where Moody's&#xae; ratings are not available, we have used S&amp;P&#xae; ratings. All ratings are as of the date indicated and do not reflect subsequent changes.




&#160;
&#160;
&#160;
&#160;
U.S. Treasury Obligations

46.1


Corporate Bonds

24.6


Bank Loan Obligations

10.5


Asset-Backed Securities

5.4


Foreign Government and Government Agency Obligations

4.0


Fixed-Income Funds

2.0


CMOs and Other Mortgage Related Securities

2.0


Preferred Securities

1.5


Common Stocks

0.5


Alternative Funds

0.4


Municipal Securities

0.2


Preferred Stocks

0.2


Short-Term Investments and Net Other Assets (Liabilities)

2.6




ASSET ALLOCATION (% of Fund's net assets)


&#160;



&#160;

U.S. Treasury Obligations - 46.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Corporate Bonds - 24.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Bank Loan Obligations - 10.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Asset-Backed Securities - 5.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Foreign Government and Government Agency Obligations - 4.0


&#160;

Fixed-Income Funds - 2.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

CMOs and Other Mortgage Related Securities - 2.0


&#160;

Preferred Securities - 1.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Common Stocks - 0.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Alternative Funds - 0.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Municipal Securities - 0.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Preferred Stocks - 0.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Short-Term Investments and Net Other Assets (Liabilities) - 2.6


&#160;






United States

83.8


United Kingdom

2.5


Canada

1.8


Mexico

1.4


Brazil

1.3


Dominican Republic

1.1


Germany

1.1


France

1.0


Israel

0.9


Others

5.1




GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

United States - 83.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

United Kingdom - 2.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Canada - 1.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Mexico - 1.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Brazil - 1.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Dominican Republic - 1.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Germany - 1.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

France - 1.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Israel - 0.9&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Others - 5.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;




&#160;




&#160;
&#160;
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    <oef:LargestHoldingsTableTextBlock contextRef="C000234191_ClassMember" id="ixv-5530">TOP HOLDINGS(% of Fund's net assets)

&#160;

&#160;


US Treasury Notes

27.1


&#160;


US Treasury Bonds

19.0


&#160;


Fidelity Real Estate High Income Fund

2.0


&#160;


Domino's Pizza Master Issuer LLC

1.9


&#160;


Petroleos Mexicanos

1.4


&#160;


Dominican Republic

1.1


&#160;


Brazilian Federative Republic

1.0


&#160;


Planet Fitness Master Issuer LLC

1.0


&#160;


Charter Communications Operating LLC / Charter Communications Operating Capital

0.9


&#160;


Millicom International Cellular SA

0.8


&#160;


&#160;

56.2

&#160;



</oef:LargestHoldingsTableTextBlock>
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      unitRef="pure">0.010</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000234191_TH_8_Member"
      decimals="INF"
      id="ixv-354105"
      unitRef="pure">0.009</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000234191_TH_9_Member"
      decimals="INF"
      id="ixv-354106"
      unitRef="pure">0.008</oef:PctOfNav>
    <oef:MaterialFundChngTextBlock contextRef="C000234191_ClassMember" id="ixv-5655">
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;How has the Fund changed?&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;This is a summary of certain changes to the Fund since September 1, 2025. For more complete information, you may review the Fund's next prospectus, which we expect to be available by October 30, 2026 at &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;fundresearch.fidelity.com/prospectus/sec&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt; or upon request at &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;1-877-208-0098&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:0px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt; or by sending an e-mail to &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;fidfunddocuments@fidelity.com&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;table cellpadding="0" cellspacing="0" style="border-collapse:collapse;border-style:none;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:50%; background-color:#ebf3e9;border-right:2px dashed #368627;padding:19px 19px 19px 19px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;The fund added a contractual management fee waiver during the reporting period. &lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:50%; background-color:#ebf3e9;padding:19px 19px 19px 19px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:MaterialFundChngTextBlock>
    <oef:SummaryOfChngLegendTextBlock contextRef="C000234191_ClassMember" id="ixv-5661">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;This is a summary of certain changes to the Fund since September 1, 2025. For more complete information, you may review the Fund's next prospectus, which we expect to be available by October 30, 2026 at &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;fundresearch.fidelity.com/prospectus/sec&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt; or upon request at &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;1-877-208-0098&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:0px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt; or by sending an e-mail to &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;fidfunddocuments@fidelity.com&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;.&lt;/span&gt;</oef:SummaryOfChngLegendTextBlock>
    <oef:UpdProspectusWebAddress contextRef="C000234191_ClassMember" id="ixv-5663">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;fundresearch.fidelity.com/prospectus/sec&lt;/span&gt;</oef:UpdProspectusWebAddress>
    <oef:UpdProspectusPhoneNumber contextRef="C000234191_ClassMember" id="ixv-5666">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;1-877-208-0098&lt;/span&gt;</oef:UpdProspectusPhoneNumber>
    <oef:UpdProspectusEmailAddress contextRef="C000234191_ClassMember" id="ixv-5670">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;fidfunddocuments@fidelity.com&lt;/span&gt;</oef:UpdProspectusEmailAddress>
    <oef:MaterialFundChngExpensesTextBlock contextRef="C000234191_ClassMember" id="ixv-5681">
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;The fund added a contractual management fee waiver during the reporting period. &lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:MaterialFundChngExpensesTextBlock>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-5739">2026-08-31</dei:DocumentPeriodEndDate>
    <oef:MaterialFundChngNoticeTextBlock contextRef="C000235214_ClassMember" id="ixv-5743">This report describes changes to the Fund that occurred during the reporting period.</oef:MaterialFundChngNoticeTextBlock>
    <oef:FundName contextRef="C000235214_ClassMember" id="ixv-5754">Fidelity&#xae; SAI Sustainable Core Plus Bond Fund</oef:FundName>
    <oef:ClassName contextRef="C000235214_ClassMember" id="ixv-5757">Fidelity&#xae; SAI Sustainable Core Plus Bond Fund</oef:ClassName>
    <dei:TradingSymbol contextRef="C000235214_ClassMember" id="ixv-5761">FIABX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000235214_ClassMember" id="ixv-5780">This annual shareholder report contains information about Fidelity&#xae; SAI Sustainable Core Plus Bond Fund for the period September 1, 2025 to August 31, 2026.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000235214_ClassMember" id="ixv-5782">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000235214_ClassMember" id="ixv-5787">You can find additional information about the Fund at fundresearch.fidelity.com/prospectus/sec. You can also request this information by contacting us at 1-800-544-3455 or by sending an e-mail to fidfunddocuments@fidelity.com.</oef:AddlInfoTextBlock>
    <oef:AddlInfoWebsite contextRef="C000235214_ClassMember" id="ixv-5789">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000235214_ClassMember" id="ixv-5792">1-800-544-3455</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000235214_ClassMember" id="ixv-5795">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000235214_ClassMember" id="ixv-5802">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What were your Fund costs for the last year?&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(based on hypothetical $10,000 investment)&lt;/span&gt;&lt;/div&gt;
&lt;div&gt;&lt;span style="font-size:11px;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:bold;"&gt;FUND COST (PREVIOUS YEAR)&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;table cellpadding="0" cellspacing="0" style="border-collapse:collapse;border-style:none;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:51%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:21%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;Costs of a $10,000 investment&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:27%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;Costs paid as a percentage of a $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:51%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity&#xae; SAI Sustainable Core Plus Bond Fund&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:21%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;36&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:27%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;0.36&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:ExpensesTextBlock>
    <oef:ExpensesPaidAmt
      contextRef="C000235214_ClassMember"
      decimals="0"
      id="ixv-354107"
      unitRef="usd">36</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000235214_ClassMember"
      decimals="INF"
      id="ixv-354108"
      unitRef="pure">0.0036</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000235214_ClassMember" id="ixv-5845">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What affected the Fund's performance this period?&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;U.S. taxable investment-grade bonds achieved a gain for the 12 months ending August 31, 2026, buoyed by three policy interest-rate cuts by the Federal Reserve in late 2025, but pulled down since then by rising bond yields amid higher consumer inflation, a resilient economy and heavy U.S. Treasury issuance.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Against this backdrop, allocations to "plus sectors," led by high-yield bonds, notably contributed to the fund's performance versus the benchmark Bloomberg U.S. Aggregate Index for the fiscal year.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Modest non-benchmark exposure to leveraged loans also provided a boost.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Among investment-grade bonds, overweight holdings and investment choices among asset-backed securities, especially collateralized loan obligations, added value.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;In contrast, underweight holdings in investment-grade corporate bonds, particularly below-benchmark exposure to industrials, detracted from the fund's relative performance.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;An underweight in mortgage-backed securities modestly hurt as well.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Notable changes over the past 12 months included management's decision to gradually lower the fund's overall risk profile by slightly reducing exposure to investment-grade corporate bonds and increasing the allocation to mortgage-backed securities in the second half of the period.&lt;/span&gt;&lt;/div&gt;
&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:italic;font-weight:normal;"&gt;Application of FMR's environmental, social, and governance ratings process and/or its sustainable investing exclusion criteria may affect the Fund's exposure to certain issuers, sectors, regions and countries and may affect the Fund's performance.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:FactorsAffectingPerfTextBlock>
    <oef:LineGraphTableTextBlock contextRef="C000235214_ClassMember" id="ixv-5876">How did the Fund perform over the life of Fund?

 &#160;&#160;
CUMULATIVE PERFORMANCE
April 13, 2022 through August 31, 2026. 
Initial investment of $10,000.
Fidelity&#xae; SAI Sustainable Core Plus Bond Fund


$10,000

$9,587


$9,551


$10,249


$10,588



Bloomberg MSCI U.S. Aggregate ESG Choice Bond Index


$10,000

$9,702


$9,590


$10,286


$10,612



Bloomberg U.S. Aggregate Bond Index


$10,000

$9,696


$9,581


$10,280


$10,602



&#160;

2022

2023

2024

2025

2026









&#160;
</oef:LineGraphTableTextBlock>
    <oef:LineGraphAndTableMeasureName contextRef="C000235214_LG_ClassMember_5YR" id="ixv-5895">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity&#xae; SAI Sustainable Core Plus Bond Fund&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000235214_ClassMember_AsOf_2022"
      decimals="0"
      id="ixv-354109"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235214_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-354110"
      unitRef="usd">9587</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235214_ClassMember_AsOf_2024"
      decimals="0"
      id="ixv-354111"
      unitRef="usd">9551</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235214_ClassMember_AsOf_2025"
      decimals="0"
      id="ixv-354112"
      unitRef="usd">10249</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235214_ClassMember_AsOf_2026"
      decimals="0"
      id="ixv-354113"
      unitRef="usd">10588</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000235214_LG_1_AdditionalIndexMember_5YR"
      id="ixv-5920">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg MSCI U.S. Aggregate ESG Choice Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000235214_1_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-354114"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235214_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-354115"
      unitRef="usd">9702</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235214_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-354116"
      unitRef="usd">9590</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235214_1_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-354117"
      unitRef="usd">10286</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235214_1_AdditionalIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-354118"
      unitRef="usd">10612</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000235214_LG_2_AdditionalIndexMember_5YR"
      id="ixv-5945">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg U.S. Aggregate Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000235214_2_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-354119"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235214_2_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-354120"
      unitRef="usd">9696</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235214_2_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-354121"
      unitRef="usd">9581</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235214_2_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-354122"
      unitRef="usd">10280</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235214_2_AdditionalIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-354123"
      unitRef="usd">10602</oef:AccmVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000235214_ClassMember" id="ixv-6004">AVERAGE ANNUAL TOTAL RETURNS:

&#160;

1 Year

Life of Fund&#160;A


Fidelity&#xae; SAI Sustainable Core Plus Bond Fund

1.78%

1.72%


Bloomberg MSCI U.S. Aggregate ESG Choice Bond Index

1.87%


1.79%


Bloomberg U.S. Aggregate Bond Index

1.89%


1.78%




A&#160; &#160;From April 13, 2022

&#160;
Visit www.fidelity.com for more recent performance information.&#160;

&#160;


The Fund's past performance is not a good predictor of the Fund's future performance. &#160;The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.





</oef:AvgAnnlRtrTableTextBlock>
    <oef:AvgAnnlRtrPct
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      unitRef="pure">0.0172</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
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      id="ixv-354126"
      unitRef="pure">0.0187</oef:AvgAnnlRtrPct>
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    <oef:AvgAnnlRtrPct
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      id="ixv-354128"
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      id="ixv-6059">2022-04-13</oef:PerfInceptionDate>
    <oef:UpdPerfInfoLocationTextBlock contextRef="C000235214_ClassMember" id="ixv-6069">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Visit &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;www.fidelity.com&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt; for more recent performance information.&lt;/span&gt;</oef:UpdPerfInfoLocationTextBlock>
    <oef:PerformancePastDoesNotIndicateFuture contextRef="C000235214_ClassMember" id="ixv-6081">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:italic;font-weight:normal;"&gt;The Fund's past performance is not a good predictor of the Fund's future performance.&lt;/span&gt;</oef:PerformancePastDoesNotIndicateFuture>
    <oef:NoDeductionOfTaxesTextBlock contextRef="C000235214_ClassMember" id="ixv-6085">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.&lt;/span&gt;</oef:NoDeductionOfTaxesTextBlock>
    <oef:AddlFundStatisticsTextBlock contextRef="C000235214_ClassMember" id="ixv-6091">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;Key Fund Statistics&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(as of August 31, 2026)&lt;/span&gt;&lt;/div&gt;
&lt;div&gt;&lt;span style="font-size:11px;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;table cellpadding="0" cellspacing="1" style="border-collapse:separate;border-style:none;margin:auto;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:63%; " valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:bold;"&gt;KEY FACTS&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt; &lt;span&gt;&#160;&lt;/span&gt;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fund Size&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;260,772,375&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;1,069&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;602,351&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="middle"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Portfolio Turnover&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;185&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:AddlFundStatisticsTextBlock>
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&#160;
U.S. Government and U.S. Government Agency Obligations

64.3


AAA

5.0


AA

0.8


A

9.0


BBB

10.4


BB

4.0


B

1.7


CCC,CC,C

0.8


Not Rated

2.7


Equities

0.0


Short-Term Investments and Net Other Assets (Liabilities)

1.3




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

U.S. Government and U.S. Government Agency Obligations - 64.3


&#160;

AAA - 5.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

AA - 0.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

A - 9.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BBB - 10.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BB - 4.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

B - 1.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

CCC,CC,C - 0.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Not Rated - 2.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Equities - 0.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Short-Term Investments and Net Other Assets (Liabilities) - 1.3


&#160;


We have used ratings from Moody's Investors Service, Inc. Where Moody's&#xae; ratings are not available, we have used S&amp;P&#xae; ratings. All ratings are as of the date indicated and do not reflect subsequent changes.




&#160;
&#160;
&#160;
&#160;
U.S. Treasury Obligations

47.2


Corporate Bonds

25.2


U.S. Government Agency - Mortgage Securities

17.1


Asset-Backed Securities

5.9


CMOs and Other Mortgage Related Securities

1.4


Bank Loan Obligations

0.9


Foreign Government and Government Agency Obligations

0.8


Preferred Securities

0.1


Other Investments

0.1


Preferred Stocks

0.0


Common Stocks

0.0


Short-Term Investments and Net Other Assets (Liabilities)

1.3




ASSET ALLOCATION (% of Fund's net assets)


&#160;



&#160;

U.S. Treasury Obligations - 47.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Corporate Bonds - 25.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

U.S. Government Agency - Mortgage Securities - 17.1


&#160;

Asset-Backed Securities - 5.9&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

CMOs and Other Mortgage Related Securities - 1.4


&#160;

Bank Loan Obligations - 0.9&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Foreign Government and Government Agency Obligations - 0.8


&#160;

Preferred Securities - 0.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Other Investments - 0.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Preferred Stocks - 0.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Common Stocks - 0.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Short-Term Investments and Net Other Assets (Liabilities) - 1.3


&#160;






United States

86.6


Grand Cayman (UK Overseas Ter)

3.6


United Kingdom

1.8


Bailiwick Of Jersey

1.3


Italy

1.0


France

0.8


Germany

0.7


Japan

0.7


Netherlands

0.6


Others

2.9




GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

United States - 86.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Grand Cayman (UK Overseas Ter) - 3.6&#160;&#160;&#160;&#160;


&#160;

United Kingdom - 1.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Bailiwick Of Jersey - 1.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Italy - 1.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

France - 0.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Germany - 0.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Japan - 0.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Netherlands - 0.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Others - 2.9&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;




&#160;




&#160;
&#160;
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      unitRef="pure">0.007</oef:PctOfNav>
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      contextRef="C000235214_GD_JP_Member"
      decimals="INF"
      id="ixv-354164"
      unitRef="pure">0.007</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235214_GD_NL_Member"
      decimals="INF"
      id="ixv-354165"
      unitRef="pure">0.006</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235214_GD_Other_Member"
      decimals="INF"
      id="ixv-354166"
      unitRef="pure">0.029</oef:PctOfNav>
    <oef:LargestHoldingsTableTextBlock contextRef="C000235214_ClassMember" id="ixv-6692">TOP HOLDINGS(% of Fund's net assets)

&#160;

&#160;


US Treasury Notes

35.8


&#160;


US Treasury Bonds

11.4


&#160;


Fannie Mae Mortgage pass-thru certificates

5.5


&#160;


Uniform Mortgage Backed Securities

4.2


&#160;


Ginnie Mae II Pool

3.6


&#160;


Freddie Mac Gold Pool

3.4


&#160;


Bank of America Corp

1.0


&#160;


JPMorgan Chase &amp; Co

0.9


&#160;


Morgan Stanley

0.9


&#160;


ENEL Finance International NV

0.5


&#160;


&#160;

67.2

&#160;



</oef:LargestHoldingsTableTextBlock>
    <oef:PctOfNav
      contextRef="C000235214_TH_0_Member"
      decimals="INF"
      id="ixv-354167"
      unitRef="pure">0.358</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235214_TH_1_Member"
      decimals="INF"
      id="ixv-354168"
      unitRef="pure">0.114</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235214_TH_2_Member"
      decimals="INF"
      id="ixv-354169"
      unitRef="pure">0.055</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235214_TH_3_Member"
      decimals="INF"
      id="ixv-354170"
      unitRef="pure">0.042</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235214_TH_4_Member"
      decimals="INF"
      id="ixv-354171"
      unitRef="pure">0.036</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235214_TH_5_Member"
      decimals="INF"
      id="ixv-354172"
      unitRef="pure">0.034</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235214_TH_6_Member"
      decimals="INF"
      id="ixv-354173"
      unitRef="pure">0.010</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235214_TH_7_Member"
      decimals="INF"
      id="ixv-354174"
      unitRef="pure">0.009</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235214_TH_8_Member"
      decimals="INF"
      id="ixv-354175"
      unitRef="pure">0.009</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235214_TH_9_Member"
      decimals="INF"
      id="ixv-354176"
      unitRef="pure">0.005</oef:PctOfNav>
    <oef:MaterialFundChngTextBlock contextRef="C000235214_ClassMember" id="ixv-6817">
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;How has the Fund changed?&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;This is a summary of certain changes to the Fund since September 1, 2025. For more complete information, you may review the Fund's next prospectus, which we expect to be available by October 30, 2026 at &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;fundresearch.fidelity.com/prospectus/sec&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt; or upon request at &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;1-800-544-3455&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:0px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt; or by sending an e-mail to &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;fidfunddocuments@fidelity.com&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;table cellpadding="0" cellspacing="0" style="border-collapse:collapse;border-style:none;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:50%; background-color:#ebf3e9;border-right:2px dashed #368627;padding:19px 19px 19px 19px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;The fund modified its principal investment strategies during the reporting period.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:50%; background-color:#ebf3e9;padding:19px 19px 19px 19px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:MaterialFundChngTextBlock>
    <oef:SummaryOfChngLegendTextBlock contextRef="C000235214_ClassMember" id="ixv-6823">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;This is a summary of certain changes to the Fund since September 1, 2025. For more complete information, you may review the Fund's next prospectus, which we expect to be available by October 30, 2026 at &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;fundresearch.fidelity.com/prospectus/sec&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt; or upon request at &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;1-800-544-3455&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:0px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt; or by sending an e-mail to &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;fidfunddocuments@fidelity.com&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;.&lt;/span&gt;</oef:SummaryOfChngLegendTextBlock>
    <oef:UpdProspectusWebAddress contextRef="C000235214_ClassMember" id="ixv-6825">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;fundresearch.fidelity.com/prospectus/sec&lt;/span&gt;</oef:UpdProspectusWebAddress>
    <oef:UpdProspectusPhoneNumber contextRef="C000235214_ClassMember" id="ixv-6828">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;1-800-544-3455&lt;/span&gt;</oef:UpdProspectusPhoneNumber>
    <oef:UpdProspectusEmailAddress contextRef="C000235214_ClassMember" id="ixv-6832">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;fidfunddocuments@fidelity.com&lt;/span&gt;</oef:UpdProspectusEmailAddress>
    <oef:MaterialFundChngStrategiesTextBlock contextRef="C000235214_ClassMember" id="ixv-6843">
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;The fund modified its principal investment strategies during the reporting period.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:MaterialFundChngStrategiesTextBlock>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-6901">2026-08-31</dei:DocumentPeriodEndDate>
    <oef:FundName contextRef="C000171440_ClassMember" id="ixv-6913">Fidelity&#xae; Short-Term Bond Fund</oef:FundName>
    <oef:ClassName contextRef="C000171440_ClassMember" id="ixv-6916">Fidelity Advisor&#xae; Short-Term Bond Fund Class I</oef:ClassName>
    <dei:TradingSymbol contextRef="C000171440_ClassMember" id="ixv-6920">FBNIX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000171440_ClassMember" id="ixv-6939">This annual shareholder report contains information about Fidelity&#xae; Short-Term Bond Fund for the period September 1, 2025 to August 31, 2026.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000171440_ClassMember" id="ixv-6941">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000171440_ClassMember" id="ixv-6946">You can find additional information about the Fund at fundresearch.fidelity.com/prospectus/sec. You can also request this information by contacting us at 1-877-208-0098 or by sending an e-mail to fidfunddocuments@fidelity.com.</oef:AddlInfoTextBlock>
    <oef:AddlInfoWebsite contextRef="C000171440_ClassMember" id="ixv-6948">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000171440_ClassMember" id="ixv-6951">1-877-208-0098</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000171440_ClassMember" id="ixv-6954">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000171440_ClassMember" id="ixv-6961">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What were your Fund costs for the last year?&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(based on hypothetical $10,000 investment)&lt;/span&gt;&lt;/div&gt;
&lt;div&gt;&lt;span style="font-size:11px;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:bold;"&gt;FUND COST (PREVIOUS YEAR)&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;table cellpadding="0" cellspacing="0" style="border-collapse:collapse;border-style:none;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:51%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:21%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;Costs of a $10,000 investment&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:27%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;Costs paid as a percentage of a $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:51%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;Class I&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:21%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;30&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:27%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;0.30&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:ExpensesTextBlock>
    <oef:ExpensesPaidAmt
      contextRef="C000171440_ClassMember"
      decimals="0"
      id="ixv-354177"
      unitRef="usd">30</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000171440_ClassMember"
      decimals="INF"
      id="ixv-354178"
      unitRef="pure">0.0030</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000171440_ClassMember" id="ixv-7004">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What affected the Fund's performance this period?&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;U.S. taxable investment-grade bonds achieved a gain for the 12 months ending August 31, 2026, buoyed by three policy interest-rate cuts by the Federal Reserve in late 2025, but pulled down since then by rising bond yields amid higher consumer inflation, a resilient economy and heavy U.S. Treasury issuance.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Against this backdrop, the fund's strategy of favoring short-term corporate bonds, while underweighting similar-duration U.S. Treasurys, contributed to its performance versus the benchmark Bloomberg U.S. 1-3 Year Government/Credit Bond Index for the fiscal year. Within corporates, debt holdings among financial institutions, especially banks, added notable value.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Non-benchmark exposure to asset-backed securities, including car loan debt and collateralized loan obligations, also meaningfully helped.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;In contrast, the fund's yield-curve positioning, including the underweighting of one-year maturities in favor of two- and three-year positions, detracted from relative performance.&#160;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;At fiscal year-end, corporates made up about 40% of fund assets, down from 41% a year ago but still notably overweight versus the benchmark average of 22%. Exposure to U.S. Treasurys stood at roughly 43% at the end of the period, up from 35% a year ago and compared with an average of about 72% for the 1-3 year benchmark. Exposure to ABS fell from roughly 18% of assets to about 12% as of August 31.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:FactorsAffectingPerfTextBlock>
    <oef:LineGraphTableTextBlock contextRef="C000171440_ClassMember" id="ixv-7025">How did the Fund perform over the past 10 years?

 &#160;&#160;
CUMULATIVE PERFORMANCE
August 31, 2016 through August 31, 2026. 
Initial investment of $10,000.
Class I


$10,000

$10,097


$10,124


$10,558


$10,967


$11,005


$10,538


$10,778


$11,504


$12,067


$12,377



Bloomberg U.S. 1-3 Year Government/Credit Bond Index


$10,000

$10,090


$10,106


$10,572


$10,960


$11,003


$10,565


$10,730


$11,401


$11,930


$12,251



Bloomberg U.S. Aggregate Bond Index


$10,000

$10,049


$9,944


$10,955


$11,665


$11,655


$10,313


$10,189


$10,933


$11,276


$11,489



&#160;

2016

2017

2018

2019

2020

2021

2022

2023

2024

2025

2026









&#160;
</oef:LineGraphTableTextBlock>
    <oef:LineGraphAndTableMeasureName contextRef="C000171440_LG_ClassMember_11YR" id="ixv-7044">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Class I&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000171440_ClassMember_AsOf_2016"
      decimals="0"
      id="ixv-354179"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171440_ClassMember_AsOf_2017"
      decimals="0"
      id="ixv-354180"
      unitRef="usd">10097</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171440_ClassMember_AsOf_2018"
      decimals="0"
      id="ixv-354181"
      unitRef="usd">10124</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171440_ClassMember_AsOf_2019"
      decimals="0"
      id="ixv-354182"
      unitRef="usd">10558</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171440_ClassMember_AsOf_2020"
      decimals="0"
      id="ixv-354183"
      unitRef="usd">10967</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171440_ClassMember_AsOf_2021"
      decimals="0"
      id="ixv-354184"
      unitRef="usd">11005</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171440_ClassMember_AsOf_2022"
      decimals="0"
      id="ixv-354185"
      unitRef="usd">10538</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171440_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-354186"
      unitRef="usd">10778</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171440_ClassMember_AsOf_2024"
      decimals="0"
      id="ixv-354187"
      unitRef="usd">11504</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171440_ClassMember_AsOf_2025"
      decimals="0"
      id="ixv-354188"
      unitRef="usd">12067</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171440_ClassMember_AsOf_2026"
      decimals="0"
      id="ixv-354189"
      unitRef="usd">12377</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000171440_LG_1_AdditionalIndexMember_11YR"
      id="ixv-7093">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg U.S. 1-3 Year Government/Credit Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000171440_1_AdditionalIndexMember_AsOf_2016"
      decimals="0"
      id="ixv-354190"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171440_1_AdditionalIndexMember_AsOf_2017"
      decimals="0"
      id="ixv-354191"
      unitRef="usd">10090</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171440_1_AdditionalIndexMember_AsOf_2018"
      decimals="0"
      id="ixv-354192"
      unitRef="usd">10106</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171440_1_AdditionalIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-354193"
      unitRef="usd">10572</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171440_1_AdditionalIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-354194"
      unitRef="usd">10960</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171440_1_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-354195"
      unitRef="usd">11003</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171440_1_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-354196"
      unitRef="usd">10565</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171440_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-354197"
      unitRef="usd">10730</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171440_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-354198"
      unitRef="usd">11401</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171440_1_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-354199"
      unitRef="usd">11930</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171440_1_AdditionalIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-354200"
      unitRef="usd">12251</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000171440_LG_2_AdditionalIndexMember_11YR"
      id="ixv-7142">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg U.S. Aggregate Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000171440_2_AdditionalIndexMember_AsOf_2016"
      decimals="0"
      id="ixv-354201"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171440_2_AdditionalIndexMember_AsOf_2017"
      decimals="0"
      id="ixv-354202"
      unitRef="usd">10049</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171440_2_AdditionalIndexMember_AsOf_2018"
      decimals="0"
      id="ixv-354203"
      unitRef="usd">9944</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171440_2_AdditionalIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-354204"
      unitRef="usd">10955</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171440_2_AdditionalIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-354205"
      unitRef="usd">11665</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171440_2_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-354206"
      unitRef="usd">11655</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171440_2_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-354207"
      unitRef="usd">10313</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171440_2_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-354208"
      unitRef="usd">10189</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171440_2_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-354209"
      unitRef="usd">10933</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171440_2_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-354210"
      unitRef="usd">11276</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171440_2_AdditionalIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-354211"
      unitRef="usd">11489</oef:AccmVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000171440_ClassMember" id="ixv-7243">AVERAGE ANNUAL TOTAL RETURNS:

&#160;

1 Year

5 Year

10 Year


Class I

2.58%

2.38%

2.16%


Bloomberg U.S. 1-3 Year Government/Credit Bond Index

2.69%


2.17%


2.05%


Bloomberg U.S. Aggregate Bond Index

1.89%


-0.29%


1.40%




&#160;
&#160;
Visit institutional.fidelity.com for more recent performance information.&#160;

&#160;


The Fund's past performance is not a good predictor of the Fund's future performance. &#160;The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.





</oef:AvgAnnlRtrTableTextBlock>
    <oef:AvgAnnlRtrPct
      contextRef="C000171440_NoLoadClassMember_1YR"
      decimals="INF"
      id="ixv-354212"
      unitRef="pure">0.0258</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000171440_NoLoadClassMember_5YR"
      decimals="INF"
      id="ixv-354213"
      unitRef="pure">0.0238</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000171440_NoLoadClassMember_10YR"
      decimals="INF"
      id="ixv-354214"
      unitRef="pure">0.0216</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000171440_0_AdditionalIndexMember_1YR"
      decimals="INF"
      id="ixv-354215"
      unitRef="pure">0.0269</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000171440_0_AdditionalIndexMember_5YR"
      decimals="INF"
      id="ixv-354216"
      unitRef="pure">0.0217</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000171440_0_AdditionalIndexMember_10YR"
      decimals="INF"
      id="ixv-354217"
      unitRef="pure">0.0205</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000171440_1_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-354218"
      unitRef="pure">0.0189</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000171440_1_BBIndexMember_5YR"
      decimals="INF"
      id="ixv-354219"
      unitRef="pure">-0.0029</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000171440_1_BBIndexMember_10YR"
      decimals="INF"
      id="ixv-354220"
      unitRef="pure">0.0140</oef:AvgAnnlRtrPct>
    <oef:UpdPerfInfoLocationTextBlock contextRef="C000171440_ClassMember" id="ixv-7314">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Visit &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;institutional.fidelity.com&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt; for more recent performance information.&lt;/span&gt;</oef:UpdPerfInfoLocationTextBlock>
    <oef:PerformancePastDoesNotIndicateFuture contextRef="C000171440_ClassMember" id="ixv-7326">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:italic;font-weight:normal;"&gt;The Fund's past performance is not a good predictor of the Fund's future performance.&lt;/span&gt;</oef:PerformancePastDoesNotIndicateFuture>
    <oef:NoDeductionOfTaxesTextBlock contextRef="C000171440_ClassMember" id="ixv-7330">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.&lt;/span&gt;</oef:NoDeductionOfTaxesTextBlock>
    <oef:AddlFundStatisticsTextBlock contextRef="C000171440_ClassMember" id="ixv-7336">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;Key Fund Statistics&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(as of August 31, 2026)&lt;/span&gt;&lt;/div&gt;
&lt;div&gt;&lt;span style="font-size:11px;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;table cellpadding="0" cellspacing="1" style="border-collapse:separate;border-style:none;margin:auto;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:63%; " valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:bold;"&gt;KEY FACTS&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt; &lt;span&gt;&#160;&lt;/span&gt;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fund Size&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;2,843,357,688&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;483&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;5,198,445&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="middle"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Portfolio Turnover&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;95&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:AddlFundStatisticsTextBlock>
    <us-gaap:AssetsNet
      contextRef="C000171440_InstantMember"
      decimals="0"
      id="ixv-354221"
      unitRef="usd">2843357688</us-gaap:AssetsNet>
    <oef:HoldingsCount
      contextRef="C000171440_InstantMember"
      decimals="INF"
      id="ixv-354222"
      unitRef="holding">483</oef:HoldingsCount>
    <oef:AdvisoryFeesPaidAmt
      contextRef="C000171440_ClassMember"
      decimals="0"
      id="ixv-354223"
      unitRef="usd">5198445</oef:AdvisoryFeesPaidAmt>
    <us-gaap:InvestmentCompanyPortfolioTurnover
      contextRef="C000171440_ClassMember"
      decimals="INF"
      id="ixv-354224"
      unitRef="pure">0.95</us-gaap:InvestmentCompanyPortfolioTurnover>
    <oef:HoldingsTableTextBlock contextRef="C000171440_ClassMember" id="ixv-7411">
&#160;
U.S. Government and U.S. Government Agency Obligations

43.3


AAA

9.9


AA

1.2


A

21.3


BBB

16.6


BB

1.4


Not Rated

5.8


Short-Term Investments and Net Other Assets (Liabilities)

0.5




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

U.S. Government and U.S. Government Agency Obligations - 43.3


&#160;

AAA - 9.9&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

AA - 1.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

A - 21.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BBB - 16.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BB - 1.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Not Rated - 5.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Short-Term Investments and Net Other Assets (Liabilities) - 0.5


&#160;


We have used ratings from Moody's Investors Service, Inc. Where Moody's&#xae; ratings are not available, we have used S&amp;P&#xae; ratings. All ratings are as of the date indicated and do not reflect subsequent changes.




&#160;
&#160;
&#160;
&#160;
U.S. Treasury Obligations

43.1


Corporate Bonds

39.1


Asset-Backed Securities

12.3


CMOs and Other Mortgage Related Securities

4.2


Other Investments

0.4


U.S. Government Agency - Mortgage Securities

0.2


Foreign Government and Government Agency Obligations

0.2


Short-Term Investments and Net Other Assets (Liabilities)

0.5




ASSET ALLOCATION (% of Fund's net assets)


&#160;



&#160;

U.S. Treasury Obligations - 43.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Corporate Bonds - 39.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Asset-Backed Securities - 12.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

CMOs and Other Mortgage Related Securities - 4.2


&#160;

Other Investments - 0.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

U.S. Government Agency - Mortgage Securities - 0.2


&#160;

Foreign Government and Government Agency Obligations - 0.2


&#160;

Short-Term Investments and Net Other Assets (Liabilities) - 0.5


&#160;






United States

78.6


Grand Cayman (UK Overseas Ter)

4.3


United Kingdom

3.6


Canada

2.8


Germany

2.7


France

1.4


Bailiwick Of Jersey

1.2


Ireland

1.1


Japan

1.0


Others

3.3




GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

United States - 78.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Grand Cayman (UK Overseas Ter) - 4.3&#160;&#160;&#160;&#160;


&#160;

United Kingdom - 3.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Canada - 2.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Germany - 2.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

France - 1.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Bailiwick Of Jersey - 1.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Ireland - 1.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Japan - 1.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Others - 3.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;




&#160;




&#160;
&#160;
</oef:HoldingsTableTextBlock>
    <oef:PctOfNav
      contextRef="C000171440_QD_USGovernmentandUSGovernmentAgencyObligations_Member"
      decimals="INF"
      id="ixv-354225"
      unitRef="pure">0.433</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000171440_QD_AAA_Member"
      decimals="INF"
      id="ixv-354226"
      unitRef="pure">0.099</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000171440_QD_AA_Member"
      decimals="INF"
      id="ixv-354227"
      unitRef="pure">0.012</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000171440_QD_A_Member"
      decimals="INF"
      id="ixv-354228"
      unitRef="pure">0.213</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000171440_QD_BBB_Member"
      decimals="INF"
      id="ixv-354229"
      unitRef="pure">0.166</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000171440_QD_BB_Member"
      decimals="INF"
      id="ixv-354230"
      unitRef="pure">0.014</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000171440_QD_NotRated_Member"
      decimals="INF"
      id="ixv-354231"
      unitRef="pure">0.058</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-354232"
      unitRef="pure">0.005</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000171440_AA_USTreasuryObligations_Member"
      decimals="INF"
      id="ixv-354233"
      unitRef="pure">0.431</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000171440_AA_CorporateBonds_Member"
      decimals="INF"
      id="ixv-354234"
      unitRef="pure">0.391</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000171440_AA_AssetBackedSecurities_Member"
      decimals="INF"
      id="ixv-354235"
      unitRef="pure">0.123</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000171440_AA_CMOsandOtherMortgageRelatedSecurities_Member"
      decimals="INF"
      id="ixv-354236"
      unitRef="pure">0.042</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000171440_AA_OtherInvestments_Member"
      decimals="INF"
      id="ixv-354237"
      unitRef="pure">0.004</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000171440_AA_USGovernmentAgencyMortgageSecurities_Member"
      decimals="INF"
      id="ixv-354238"
      unitRef="pure">0.002</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000171440_AA_ForeignGovernmentandGovernmentAgencyObligations_Member"
      decimals="INF"
      id="ixv-354239"
      unitRef="pure">0.002</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000171440_AA_ShortTermInvestmentsandNetOtherAssetsLiabilities_Member"
      decimals="INF"
      id="ixv-354240"
      unitRef="pure">0.005</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000171440_GD_US_Member"
      decimals="INF"
      id="ixv-354241"
      unitRef="pure">0.786</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000171440_GD_GrandCaymanUKOverseasTer_Member"
      decimals="INF"
      id="ixv-354242"
      unitRef="pure">0.043</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000171440_GD_GB_Member"
      decimals="INF"
      id="ixv-354243"
      unitRef="pure">0.036</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000171440_GD_CA_Member"
      decimals="INF"
      id="ixv-354244"
      unitRef="pure">0.028</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000171440_GD_DE_Member"
      decimals="INF"
      id="ixv-354245"
      unitRef="pure">0.027</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000171440_GD_FR_Member"
      decimals="INF"
      id="ixv-354246"
      unitRef="pure">0.014</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000171440_GD_BailiwickOfJersey_Member"
      decimals="INF"
      id="ixv-354247"
      unitRef="pure">0.012</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000171440_GD_IE_Member"
      decimals="INF"
      id="ixv-354248"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000171440_GD_JP_Member"
      decimals="INF"
      id="ixv-354249"
      unitRef="pure">0.010</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000171440_GD_Other_Member"
      decimals="INF"
      id="ixv-354250"
      unitRef="pure">0.033</oef:PctOfNav>
    <oef:LargestHoldingsTableTextBlock contextRef="C000171440_ClassMember" id="ixv-7846">TOP HOLDINGS(% of Fund's net assets)

&#160;

&#160;


US Treasury Notes

43.1


&#160;


Bank of America Corp

1.4


&#160;


JPMorgan Chase &amp; Co

1.3


&#160;


Wells Fargo &amp; Co

1.2


&#160;


Goldman Sachs Group Inc/The

1.0


&#160;


Citigroup Inc

0.9


&#160;


Deutsche Bank AG/New York NY

0.9


&#160;


General Motors Financial Co Inc

0.9


&#160;


Barclays PLC

0.8


&#160;


HSBC Holdings PLC

0.8


&#160;


&#160;

52.3

&#160;



</oef:LargestHoldingsTableTextBlock>
    <oef:PctOfNav
      contextRef="C000171440_TH_0_Member"
      decimals="INF"
      id="ixv-354251"
      unitRef="pure">0.431</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000171440_TH_1_Member"
      decimals="INF"
      id="ixv-354252"
      unitRef="pure">0.014</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000171440_TH_2_Member"
      decimals="INF"
      id="ixv-354253"
      unitRef="pure">0.013</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000171440_TH_3_Member"
      decimals="INF"
      id="ixv-354254"
      unitRef="pure">0.012</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000171440_TH_4_Member"
      decimals="INF"
      id="ixv-354255"
      unitRef="pure">0.010</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000171440_TH_5_Member"
      decimals="INF"
      id="ixv-354256"
      unitRef="pure">0.009</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000171440_TH_6_Member"
      decimals="INF"
      id="ixv-354257"
      unitRef="pure">0.009</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000171440_TH_7_Member"
      decimals="INF"
      id="ixv-354258"
      unitRef="pure">0.009</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000171440_TH_8_Member"
      decimals="INF"
      id="ixv-354259"
      unitRef="pure">0.008</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000171440_TH_9_Member"
      decimals="INF"
      id="ixv-354260"
      unitRef="pure">0.008</oef:PctOfNav>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-8017">2026-08-31</dei:DocumentPeriodEndDate>
    <oef:FundName contextRef="C000205020_ClassMember" id="ixv-8029">Fidelity&#xae; Short-Term Bond Fund</oef:FundName>
    <oef:ClassName contextRef="C000205020_ClassMember" id="ixv-8032">Fidelity Advisor&#xae; Short-Term Bond Fund Class Z</oef:ClassName>
    <dei:TradingSymbol contextRef="C000205020_ClassMember" id="ixv-8036">FIKTX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000205020_ClassMember" id="ixv-8055">This annual shareholder report contains information about Fidelity&#xae; Short-Term Bond Fund for the period September 1, 2025 to August 31, 2026.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000205020_ClassMember" id="ixv-8057">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000205020_ClassMember" id="ixv-8062">You can find additional information about the Fund at fundresearch.fidelity.com/prospectus/sec. You can also request this information by contacting us at 1-877-208-0098 or by sending an e-mail to fidfunddocuments@fidelity.com.</oef:AddlInfoTextBlock>
    <oef:AddlInfoWebsite contextRef="C000205020_ClassMember" id="ixv-8064">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000205020_ClassMember" id="ixv-8067">1-877-208-0098</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000205020_ClassMember" id="ixv-8070">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000205020_ClassMember" id="ixv-8077">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What were your Fund costs for the last year?&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(based on hypothetical $10,000 investment)&lt;/span&gt;&lt;/div&gt;
&lt;div&gt;&lt;span style="font-size:11px;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:bold;"&gt;FUND COST (PREVIOUS YEAR)&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;table cellpadding="0" cellspacing="0" style="border-collapse:collapse;border-style:none;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:51%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:21%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;Costs of a $10,000 investment&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:27%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;Costs paid as a percentage of a $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:51%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;Class Z&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:21%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;25&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:27%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;0.25&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:ExpensesTextBlock>
    <oef:ExpensesPaidAmt
      contextRef="C000205020_ClassMember"
      decimals="0"
      id="ixv-354261"
      unitRef="usd">25</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000205020_ClassMember"
      decimals="INF"
      id="ixv-354262"
      unitRef="pure">0.0025</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000205020_ClassMember" id="ixv-8120">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What affected the Fund's performance this period?&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;U.S. taxable investment-grade bonds achieved a gain for the 12 months ending August 31, 2026, buoyed by three policy interest-rate cuts by the Federal Reserve in late 2025, but pulled down since then by rising bond yields amid higher consumer inflation, a resilient economy and heavy U.S. Treasury issuance.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Against this backdrop, the fund's strategy of favoring short-term corporate bonds, while underweighting similar-duration U.S. Treasurys, contributed to its performance versus the benchmark Bloomberg U.S. 1-3 Year Government/Credit Bond Index for the fiscal year. Within corporates, debt holdings among financial institutions, especially banks, added notable value.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Non-benchmark exposure to asset-backed securities, including car loan debt and collateralized loan obligations, also meaningfully helped.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;In contrast, the fund's yield-curve positioning, including the underweighting of one-year maturities in favor of two- and three-year positions, detracted from relative performance.&#160;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;At fiscal year-end, corporates made up about 40% of fund assets, down from 41% a year ago but still notably overweight versus the benchmark average of 22%. Exposure to U.S. Treasurys stood at roughly 43% at the end of the period, up from 35% a year ago and compared with an average of about 72% for the 1-3 year benchmark. Exposure to ABS fell from roughly 18% of assets to about 12% as of August 31.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:FactorsAffectingPerfTextBlock>
    <oef:LineGraphTableTextBlock contextRef="C000205020_ClassMember" id="ixv-8141">How did the Fund perform over the life of Fund?

 &#160;&#160;
CUMULATIVE PERFORMANCE
October 2, 2018 through August 31, 2026. 
Initial investment of $10,000.
Class Z


$10,000

$10,450


$10,858


$10,923


$10,475


$10,725


$11,439


$12,004


$12,319



Bloomberg U.S. 1-3 Year Government/Credit Bond Index


$10,000

$10,467


$10,851


$10,893


$10,460


$10,623


$11,288


$11,811


$12,129



Bloomberg U.S. Aggregate Bond Index


$10,000

$11,086


$11,804


$11,794


$10,436


$10,311


$11,064


$11,411


$11,626



&#160;

2018

2019

2020

2021

2022

2023

2024

2025

2026









&#160;
</oef:LineGraphTableTextBlock>
    <oef:LineGraphAndTableMeasureName contextRef="C000205020_LG_ClassMember_9YR" id="ixv-8160">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Class Z&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000205020_ClassMember_AsOf_2018"
      decimals="0"
      id="ixv-354263"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000205020_ClassMember_AsOf_2019"
      decimals="0"
      id="ixv-354264"
      unitRef="usd">10450</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000205020_ClassMember_AsOf_2020"
      decimals="0"
      id="ixv-354265"
      unitRef="usd">10858</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000205020_ClassMember_AsOf_2021"
      decimals="0"
      id="ixv-354266"
      unitRef="usd">10923</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000205020_ClassMember_AsOf_2022"
      decimals="0"
      id="ixv-354267"
      unitRef="usd">10475</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000205020_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-354268"
      unitRef="usd">10725</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000205020_ClassMember_AsOf_2024"
      decimals="0"
      id="ixv-354269"
      unitRef="usd">11439</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000205020_ClassMember_AsOf_2025"
      decimals="0"
      id="ixv-354270"
      unitRef="usd">12004</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000205020_ClassMember_AsOf_2026"
      decimals="0"
      id="ixv-354271"
      unitRef="usd">12319</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000205020_LG_1_AdditionalIndexMember_9YR"
      id="ixv-8201">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg U.S. 1-3 Year Government/Credit Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000205020_1_AdditionalIndexMember_AsOf_2018"
      decimals="0"
      id="ixv-354272"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000205020_1_AdditionalIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-354273"
      unitRef="usd">10467</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000205020_1_AdditionalIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-354274"
      unitRef="usd">10851</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000205020_1_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-354275"
      unitRef="usd">10893</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000205020_1_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-354276"
      unitRef="usd">10460</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000205020_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-354277"
      unitRef="usd">10623</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000205020_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-354278"
      unitRef="usd">11288</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000205020_1_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-354279"
      unitRef="usd">11811</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000205020_1_AdditionalIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-354280"
      unitRef="usd">12129</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000205020_LG_2_AdditionalIndexMember_9YR"
      id="ixv-8242">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg U.S. Aggregate Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000205020_2_AdditionalIndexMember_AsOf_2018"
      decimals="0"
      id="ixv-354281"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000205020_2_AdditionalIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-354282"
      unitRef="usd">11086</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000205020_2_AdditionalIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-354283"
      unitRef="usd">11804</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000205020_2_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-354284"
      unitRef="usd">11794</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000205020_2_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-354285"
      unitRef="usd">10436</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000205020_2_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-354286"
      unitRef="usd">10311</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000205020_2_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-354287"
      unitRef="usd">11064</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000205020_2_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-354288"
      unitRef="usd">11411</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000205020_2_AdditionalIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-354289"
      unitRef="usd">11626</oef:AccmVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000205020_ClassMember" id="ixv-8329">AVERAGE ANNUAL TOTAL RETURNS:

&#160;

1 Year

5 Year

Life of Fund&#160;A


Class Z

2.63%

2.43%

2.67%


Bloomberg U.S. 1-3 Year Government/Credit Bond Index

2.69%


2.17%


2.47%


Bloomberg U.S. Aggregate Bond Index

1.89%


-0.29%


1.92%




A&#160; &#160;From October 2, 2018

&#160;
Visit institutional.fidelity.com for more recent performance information.&#160;

&#160;


The Fund's past performance is not a good predictor of the Fund's future performance. &#160;The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.





</oef:AvgAnnlRtrTableTextBlock>
    <oef:AvgAnnlRtrPct
      contextRef="C000205020_NoLoadClassMember_1YR"
      decimals="INF"
      id="ixv-354290"
      unitRef="pure">0.0263</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000205020_NoLoadClassMember_5YR"
      decimals="INF"
      id="ixv-354291"
      unitRef="pure">0.0243</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000205020_NoLoadClassMember_2025-09-01_2026-08-31"
      decimals="INF"
      id="ixv-354292"
      unitRef="pure">0.0267</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000205020_0_AdditionalIndexMember_1YR"
      decimals="INF"
      id="ixv-354293"
      unitRef="pure">0.0269</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000205020_0_AdditionalIndexMember_5YR"
      decimals="INF"
      id="ixv-354294"
      unitRef="pure">0.0217</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000205020_0_AdditionalIndexMember_LOC"
      decimals="INF"
      id="ixv-354295"
      unitRef="pure">0.0247</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000205020_1_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-354296"
      unitRef="pure">0.0189</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000205020_1_BBIndexMember_5YR"
      decimals="INF"
      id="ixv-354297"
      unitRef="pure">-0.0029</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000205020_1_BBIndexMember_LOC"
      decimals="INF"
      id="ixv-354298"
      unitRef="pure">0.0192</oef:AvgAnnlRtrPct>
    <oef:PerfInceptionDate
      contextRef="C000205020_Perf_2018-10-02_ClassMember"
      id="ixv-8399">2018-10-02</oef:PerfInceptionDate>
    <oef:UpdPerfInfoLocationTextBlock contextRef="C000205020_ClassMember" id="ixv-8409">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Visit &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;institutional.fidelity.com&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt; for more recent performance information.&lt;/span&gt;</oef:UpdPerfInfoLocationTextBlock>
    <oef:PerformancePastDoesNotIndicateFuture contextRef="C000205020_ClassMember" id="ixv-8421">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:italic;font-weight:normal;"&gt;The Fund's past performance is not a good predictor of the Fund's future performance.&lt;/span&gt;</oef:PerformancePastDoesNotIndicateFuture>
    <oef:NoDeductionOfTaxesTextBlock contextRef="C000205020_ClassMember" id="ixv-8425">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.&lt;/span&gt;</oef:NoDeductionOfTaxesTextBlock>
    <oef:AddlFundStatisticsTextBlock contextRef="C000205020_ClassMember" id="ixv-8431">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;Key Fund Statistics&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(as of August 31, 2026)&lt;/span&gt;&lt;/div&gt;
&lt;div&gt;&lt;span style="font-size:11px;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;table cellpadding="0" cellspacing="1" style="border-collapse:separate;border-style:none;margin:auto;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:63%; " valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:bold;"&gt;KEY FACTS&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt; &lt;span&gt;&#160;&lt;/span&gt;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fund Size&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;2,843,357,688&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;483&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;5,198,445&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="middle"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Portfolio Turnover&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;95&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:AddlFundStatisticsTextBlock>
    <us-gaap:AssetsNet
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      decimals="0"
      id="ixv-354299"
      unitRef="usd">2843357688</us-gaap:AssetsNet>
    <oef:HoldingsCount
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      id="ixv-354300"
      unitRef="holding">483</oef:HoldingsCount>
    <oef:AdvisoryFeesPaidAmt
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      decimals="0"
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      unitRef="usd">5198445</oef:AdvisoryFeesPaidAmt>
    <us-gaap:InvestmentCompanyPortfolioTurnover
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      id="ixv-354302"
      unitRef="pure">0.95</us-gaap:InvestmentCompanyPortfolioTurnover>
    <oef:HoldingsTableTextBlock contextRef="C000205020_ClassMember" id="ixv-8506">
&#160;
U.S. Government and U.S. Government Agency Obligations

43.3


AAA

9.9


AA

1.2


A

21.3


BBB

16.6


BB

1.4


Not Rated

5.8


Short-Term Investments and Net Other Assets (Liabilities)

0.5




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

U.S. Government and U.S. Government Agency Obligations - 43.3


&#160;

AAA - 9.9&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

AA - 1.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

A - 21.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BBB - 16.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BB - 1.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Not Rated - 5.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Short-Term Investments and Net Other Assets (Liabilities) - 0.5


&#160;


We have used ratings from Moody's Investors Service, Inc. Where Moody's&#xae; ratings are not available, we have used S&amp;P&#xae; ratings. All ratings are as of the date indicated and do not reflect subsequent changes.




&#160;
&#160;
&#160;
&#160;
U.S. Treasury Obligations

43.1


Corporate Bonds

39.1


Asset-Backed Securities

12.3


CMOs and Other Mortgage Related Securities

4.2


Other Investments

0.4


U.S. Government Agency - Mortgage Securities

0.2


Foreign Government and Government Agency Obligations

0.2


Short-Term Investments and Net Other Assets (Liabilities)

0.5




ASSET ALLOCATION (% of Fund's net assets)


&#160;



&#160;

U.S. Treasury Obligations - 43.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Corporate Bonds - 39.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Asset-Backed Securities - 12.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

CMOs and Other Mortgage Related Securities - 4.2


&#160;

Other Investments - 0.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

U.S. Government Agency - Mortgage Securities - 0.2


&#160;

Foreign Government and Government Agency Obligations - 0.2


&#160;

Short-Term Investments and Net Other Assets (Liabilities) - 0.5


&#160;






United States

78.6


Grand Cayman (UK Overseas Ter)

4.3


United Kingdom

3.6


Canada

2.8


Germany

2.7


France

1.4


Bailiwick Of Jersey

1.2


Ireland

1.1


Japan

1.0


Others

3.3




GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

United States - 78.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Grand Cayman (UK Overseas Ter) - 4.3&#160;&#160;&#160;&#160;


&#160;

United Kingdom - 3.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Canada - 2.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Germany - 2.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

France - 1.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Bailiwick Of Jersey - 1.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Ireland - 1.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Japan - 1.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Others - 3.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;




&#160;




&#160;
&#160;
</oef:HoldingsTableTextBlock>
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    <oef:PctOfNav
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    <oef:PctOfNav
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    <oef:PctOfNav
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    <oef:PctOfNav
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    <oef:PctOfNav
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    <oef:PctOfNav
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    <oef:PctOfNav
      contextRef="C000205020_AA_AssetBackedSecurities_Member"
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      id="ixv-354313"
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    <oef:PctOfNav
      contextRef="C000205020_AA_CMOsandOtherMortgageRelatedSecurities_Member"
      decimals="INF"
      id="ixv-354314"
      unitRef="pure">0.042</oef:PctOfNav>
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      contextRef="C000205020_AA_OtherInvestments_Member"
      decimals="INF"
      id="ixv-354315"
      unitRef="pure">0.004</oef:PctOfNav>
    <oef:PctOfNav
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      id="ixv-354316"
      unitRef="pure">0.002</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000205020_AA_ForeignGovernmentandGovernmentAgencyObligations_Member"
      decimals="INF"
      id="ixv-354317"
      unitRef="pure">0.002</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-354318"
      unitRef="pure">0.005</oef:PctOfNav>
    <oef:PctOfNav
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      id="ixv-354319"
      unitRef="pure">0.786</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000205020_GD_GrandCaymanUKOverseasTer_Member"
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      id="ixv-354320"
      unitRef="pure">0.043</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000205020_GD_GB_Member"
      decimals="INF"
      id="ixv-354321"
      unitRef="pure">0.036</oef:PctOfNav>
    <oef:PctOfNav
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      id="ixv-354322"
      unitRef="pure">0.028</oef:PctOfNav>
    <oef:PctOfNav
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      id="ixv-354323"
      unitRef="pure">0.027</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-354324"
      unitRef="pure">0.014</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000205020_GD_BailiwickOfJersey_Member"
      decimals="INF"
      id="ixv-354325"
      unitRef="pure">0.012</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000205020_GD_IE_Member"
      decimals="INF"
      id="ixv-354326"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000205020_GD_JP_Member"
      decimals="INF"
      id="ixv-354327"
      unitRef="pure">0.010</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000205020_GD_Other_Member"
      decimals="INF"
      id="ixv-354328"
      unitRef="pure">0.033</oef:PctOfNav>
    <oef:LargestHoldingsTableTextBlock contextRef="C000205020_ClassMember" id="ixv-8941">TOP HOLDINGS(% of Fund's net assets)

&#160;

&#160;


US Treasury Notes

43.1


&#160;


Bank of America Corp

1.4


&#160;


JPMorgan Chase &amp; Co

1.3


&#160;


Wells Fargo &amp; Co

1.2


&#160;


Goldman Sachs Group Inc/The

1.0


&#160;


Citigroup Inc

0.9


&#160;


Deutsche Bank AG/New York NY

0.9


&#160;


General Motors Financial Co Inc

0.9


&#160;


Barclays PLC

0.8


&#160;


HSBC Holdings PLC

0.8


&#160;


&#160;

52.3

&#160;



</oef:LargestHoldingsTableTextBlock>
    <oef:PctOfNav
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      unitRef="pure">0.431</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000205020_TH_1_Member"
      decimals="INF"
      id="ixv-354330"
      unitRef="pure">0.014</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000205020_TH_2_Member"
      decimals="INF"
      id="ixv-354331"
      unitRef="pure">0.013</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000205020_TH_3_Member"
      decimals="INF"
      id="ixv-354332"
      unitRef="pure">0.012</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000205020_TH_4_Member"
      decimals="INF"
      id="ixv-354333"
      unitRef="pure">0.010</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000205020_TH_5_Member"
      decimals="INF"
      id="ixv-354334"
      unitRef="pure">0.009</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000205020_TH_6_Member"
      decimals="INF"
      id="ixv-354335"
      unitRef="pure">0.009</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000205020_TH_7_Member"
      decimals="INF"
      id="ixv-354336"
      unitRef="pure">0.009</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000205020_TH_8_Member"
      decimals="INF"
      id="ixv-354337"
      unitRef="pure">0.008</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000205020_TH_9_Member"
      decimals="INF"
      id="ixv-354338"
      unitRef="pure">0.008</oef:PctOfNav>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-9112">2026-08-31</dei:DocumentPeriodEndDate>
    <oef:FundName contextRef="C000221555_ClassMember" id="ixv-9124">Fidelity&#xae; SAI Low Duration Bond Fund</oef:FundName>
    <oef:ClassName contextRef="C000221555_ClassMember" id="ixv-9127">Fidelity&#xae; SAI Low Duration Bond Fund</oef:ClassName>
    <dei:TradingSymbol contextRef="C000221555_ClassMember" id="ixv-9131">FZOLX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000221555_ClassMember" id="ixv-9150">This annual shareholder report contains information about Fidelity&#xae; SAI Low Duration Bond Fund for the period September 1, 2025 to August 31, 2026.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000221555_ClassMember" id="ixv-9152">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000221555_ClassMember" id="ixv-9157">You can find additional information about the Fund at fundresearch.fidelity.com/prospectus/sec. You can also request this information by contacting us at 1-800-544-3455 or by sending an e-mail to fidfunddocuments@fidelity.com.</oef:AddlInfoTextBlock>
    <oef:AddlInfoWebsite contextRef="C000221555_ClassMember" id="ixv-9159">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000221555_ClassMember" id="ixv-9162">1-800-544-3455</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000221555_ClassMember" id="ixv-9165">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000221555_ClassMember" id="ixv-9172">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What were your Fund costs for the last year?&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(based on hypothetical $10,000 investment)&lt;/span&gt;&lt;/div&gt;
&lt;div&gt;&lt;span style="font-size:11px;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:bold;"&gt;FUND COST (PREVIOUS YEAR)&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;table cellpadding="0" cellspacing="0" style="border-collapse:collapse;border-style:none;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:51%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:21%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;Costs of a $10,000 investment&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:27%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;Costs paid as a percentage of a $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:51%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity&#xae; SAI Low Duration Bond Fund&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:21%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;20&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:27%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;0.20&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:ExpensesTextBlock>
    <oef:ExpensesPaidAmt
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      id="ixv-354339"
      unitRef="usd">20</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
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      decimals="INF"
      id="ixv-354340"
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    <oef:FactorsAffectingPerfTextBlock contextRef="C000221555_ClassMember" id="ixv-9215">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What affected the Fund's performance this period?&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;U.S. taxable investment-grade bonds achieved a gain for the 12 months ending August 31, 2026, buoyed by three policy interest-rate cuts by the Federal Reserve in late 2025, but pulled down since then by rising bond yields amid higher consumer inflation, a resilient economy and heavy U.S. Treasury issuance.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Against this backdrop, the fund's strategy of holding short-term debt in high-quality corporations contributed to performance versus the all-U.S.-Treasury benchmark for the fiscal year. Within corporates, debt holdings among financial institutions, especially banks, and industrial firms, particularly in the consumer cyclical and consumer non-cyclical segments, added notable value.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Non-benchmark exposure to asset-backed securities, including car loan debt and collateralized loan obligations, also meaningfully helped.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;In contrast, the fund's yield-curve positioning detracted from relative performance.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;At period end, corporates made up about 49% of fund assets, down from roughly 51% a year ago. The portfolio's exposure to U.S. Treasurys increased from about 22% to roughly 31%, while exposure to ABS declined from approximately 23% to about 16% of assets as of August 31.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:FactorsAffectingPerfTextBlock>
    <oef:LineGraphTableTextBlock contextRef="C000221555_ClassMember" id="ixv-9236">How did the Fund perform over the life of Fund?

 &#160;&#160;
CUMULATIVE PERFORMANCE
September 15, 2020 through August 31, 2026. 
Initial investment of $10,000.
Fidelity&#xae; SAI Low Duration Bond Fund


$10,000

$10,023


$9,985


$10,438


$11,064


$11,622


$12,067



Bloomberg US Treasury Bill: 6-9 Months Index


$10,000

$10,011


$9,972


$10,282


$10,835


$11,300


$11,699



Bloomberg U.S. Aggregate Bond Index


$10,000

$9,977


$8,828


$8,723


$9,359


$9,653


$9,835



&#160;

2020

2021

2022

2023

2024

2025

2026









&#160;
</oef:LineGraphTableTextBlock>
    <oef:LineGraphAndTableMeasureName contextRef="C000221555_LG_ClassMember_7YR" id="ixv-9255">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity&#xae; SAI Low Duration Bond Fund&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000221555_ClassMember_AsOf_2020"
      decimals="0"
      id="ixv-354341"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000221555_ClassMember_AsOf_2021"
      decimals="0"
      id="ixv-354342"
      unitRef="usd">10023</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000221555_ClassMember_AsOf_2022"
      decimals="0"
      id="ixv-354343"
      unitRef="usd">9985</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000221555_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-354344"
      unitRef="usd">10438</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000221555_ClassMember_AsOf_2024"
      decimals="0"
      id="ixv-354345"
      unitRef="usd">11064</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000221555_ClassMember_AsOf_2025"
      decimals="0"
      id="ixv-354346"
      unitRef="usd">11622</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000221555_ClassMember_AsOf_2026"
      decimals="0"
      id="ixv-354347"
      unitRef="usd">12067</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000221555_LG_1_AdditionalIndexMember_7YR"
      id="ixv-9288">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg US Treasury Bill: 6-9 Months Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000221555_1_AdditionalIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-354348"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000221555_1_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-354349"
      unitRef="usd">10011</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000221555_1_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-354350"
      unitRef="usd">9972</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000221555_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-354351"
      unitRef="usd">10282</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000221555_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-354352"
      unitRef="usd">10835</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000221555_1_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-354353"
      unitRef="usd">11300</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000221555_1_AdditionalIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-354354"
      unitRef="usd">11699</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000221555_LG_2_AdditionalIndexMember_7YR"
      id="ixv-9321">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg U.S. Aggregate Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000221555_2_AdditionalIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-354355"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000221555_2_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-354356"
      unitRef="usd">9977</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000221555_2_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-354357"
      unitRef="usd">8828</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000221555_2_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-354358"
      unitRef="usd">8723</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000221555_2_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-354359"
      unitRef="usd">9359</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000221555_2_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-354360"
      unitRef="usd">9653</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000221555_2_AdditionalIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-354361"
      unitRef="usd">9835</oef:AccmVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000221555_ClassMember" id="ixv-9394">AVERAGE ANNUAL TOTAL RETURNS:

&#160;

1 Year

5 Year

Life of Fund&#160;A


Fidelity&#xae; SAI Low Duration Bond Fund

3.84%

3.78%

3.20%


Bloomberg US Treasury Bill: 6-9 Months Index

3.53%


3.17%


2.67%


Bloomberg U.S. Aggregate Bond Index

1.89%


-0.29%


-0.28%




A&#160; &#160;From September 15, 2020

&#160;
Visit www.fidelity.com for more recent performance information.&#160;

&#160;


The Fund's past performance is not a good predictor of the Fund's future performance. &#160;The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.





</oef:AvgAnnlRtrTableTextBlock>
    <oef:AvgAnnlRtrPct
      contextRef="C000221555_NoLoadClassMember_1YR"
      decimals="INF"
      id="ixv-354362"
      unitRef="pure">0.0384</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000221555_NoLoadClassMember_5YR"
      decimals="INF"
      id="ixv-354363"
      unitRef="pure">0.0378</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000221555_NoLoadClassMember_2025-09-01_2026-08-31"
      decimals="INF"
      id="ixv-354364"
      unitRef="pure">0.0320</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000221555_0_AdditionalIndexMember_1YR"
      decimals="INF"
      id="ixv-354365"
      unitRef="pure">0.0353</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000221555_0_AdditionalIndexMember_5YR"
      decimals="INF"
      id="ixv-354366"
      unitRef="pure">0.0317</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000221555_0_AdditionalIndexMember_LOC"
      decimals="INF"
      id="ixv-354367"
      unitRef="pure">0.0267</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000221555_1_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-354368"
      unitRef="pure">0.0189</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000221555_1_BBIndexMember_5YR"
      decimals="INF"
      id="ixv-354369"
      unitRef="pure">-0.0029</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000221555_1_BBIndexMember_LOC"
      decimals="INF"
      id="ixv-354370"
      unitRef="pure">-0.0028</oef:AvgAnnlRtrPct>
    <oef:PerfInceptionDate
      contextRef="C000221555_Perf_2020-09-15_ClassMember"
      id="ixv-9465">2020-09-15</oef:PerfInceptionDate>
    <oef:UpdPerfInfoLocationTextBlock contextRef="C000221555_ClassMember" id="ixv-9475">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Visit &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;www.fidelity.com&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt; for more recent performance information.&lt;/span&gt;</oef:UpdPerfInfoLocationTextBlock>
    <oef:PerformancePastDoesNotIndicateFuture contextRef="C000221555_ClassMember" id="ixv-9487">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:italic;font-weight:normal;"&gt;The Fund's past performance is not a good predictor of the Fund's future performance.&lt;/span&gt;</oef:PerformancePastDoesNotIndicateFuture>
    <oef:NoDeductionOfTaxesTextBlock contextRef="C000221555_ClassMember" id="ixv-9491">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.&lt;/span&gt;</oef:NoDeductionOfTaxesTextBlock>
    <oef:AddlFundStatisticsTextBlock contextRef="C000221555_ClassMember" id="ixv-9497">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;Key Fund Statistics&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(as of August 31, 2026)&lt;/span&gt;&lt;/div&gt;
&lt;div&gt;&lt;span style="font-size:11px;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;table cellpadding="0" cellspacing="1" style="border-collapse:separate;border-style:none;margin:auto;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:63%; " valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:bold;"&gt;KEY FACTS&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt; &lt;span&gt;&#160;&lt;/span&gt;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fund Size&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;3,154,815,409&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;349&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;8,348,734&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="middle"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Portfolio Turnover&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;62&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:AddlFundStatisticsTextBlock>
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&#160;
U.S. Government and U.S. Government Agency Obligations

30.5


AAA

15.7


AA

5.0


A

30.6


BBB

12.3


BB

0.4


Not Rated

2.4


Short-Term Investments and Net Other Assets (Liabilities)

3.1




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

U.S. Government and U.S. Government Agency Obligations - 30.5


&#160;

AAA - 15.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

AA - 5.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

A - 30.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BBB - 12.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BB - 0.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Not Rated - 2.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Short-Term Investments and Net Other Assets (Liabilities) - 3.1


&#160;


We have used ratings from Moody's Investors Service, Inc. Where Moody's&#xae; ratings are not available, we have used S&amp;P&#xae; ratings. All ratings are as of the date indicated and do not reflect subsequent changes.




&#160;
&#160;
&#160;
&#160;
Corporate Bonds

47.9


U.S. Treasury Obligations

30.5


Asset-Backed Securities

16.5


CMOs and Other Mortgage Related Securities

1.9


Other Investments

0.1


Short-Term Investments and Net Other Assets (Liabilities)

3.1




ASSET ALLOCATION (% of Fund's net assets)


&#160;



&#160;

Corporate Bonds - 47.9&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

U.S. Treasury Obligations - 30.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Asset-Backed Securities - 16.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

CMOs and Other Mortgage Related Securities - 1.9


&#160;

Other Investments - 0.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Short-Term Investments and Net Other Assets (Liabilities) - 3.1


&#160;






United States

75.2


United Kingdom

5.4


Canada

5.2


Grand Cayman (UK Overseas Ter)

3.8


Germany

2.2


Netherlands

1.7


Japan

1.7


France

1.0


Switzerland

1.0


Others

2.8




GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

United States - 75.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

United Kingdom - 5.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Canada - 5.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Grand Cayman (UK Overseas Ter) - 3.8&#160;&#160;&#160;&#160;


&#160;

Germany - 2.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Netherlands - 1.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Japan - 1.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

France - 1.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Switzerland - 1.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Others - 2.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;




&#160;




&#160;
&#160;
</oef:HoldingsTableTextBlock>
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    <oef:PctOfNav
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    <oef:PctOfNav
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      id="ixv-354385"
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    <oef:PctOfNav
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      decimals="INF"
      id="ixv-354386"
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    <oef:PctOfNav
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    <oef:PctOfNav
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      unitRef="pure">0.752</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
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      unitRef="pure">0.054</oef:PctOfNav>
    <oef:PctOfNav
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      unitRef="pure">0.052</oef:PctOfNav>
    <oef:PctOfNav
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      id="ixv-354392"
      unitRef="pure">0.038</oef:PctOfNav>
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      unitRef="pure">0.022</oef:PctOfNav>
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      unitRef="pure">0.017</oef:PctOfNav>
    <oef:PctOfNav
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      unitRef="pure">0.017</oef:PctOfNav>
    <oef:PctOfNav
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      id="ixv-354396"
      unitRef="pure">0.010</oef:PctOfNav>
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      id="ixv-354397"
      unitRef="pure">0.010</oef:PctOfNav>
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    <oef:LargestHoldingsTableTextBlock contextRef="C000221555_ClassMember" id="ixv-9981">TOP HOLDINGS(% of Fund's net assets)

&#160;

&#160;


US Treasury Notes

19.1


&#160;


US Treasury Bill

11.4


&#160;


Wells Fargo &amp; Co

1.7


&#160;


JPMorgan Chase &amp; Co

1.6


&#160;


Bank of America Corp

1.6


&#160;


Royal Bank of Canada

1.3


&#160;


Goldman Sachs Group Inc/The

1.2


&#160;


GMF Floorplan Owner Revolving Trust

1.1


&#160;


Barclays PLC

1.0


&#160;


Bank of Montreal

0.9


&#160;


&#160;

40.9

&#160;



</oef:LargestHoldingsTableTextBlock>
    <oef:PctOfNav
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      id="ixv-354399"
      unitRef="pure">0.191</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-354400"
      unitRef="pure">0.114</oef:PctOfNav>
    <oef:PctOfNav
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      id="ixv-354401"
      unitRef="pure">0.017</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-354402"
      unitRef="pure">0.016</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
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      unitRef="pure">0.016</oef:PctOfNav>
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      unitRef="pure">0.010</oef:PctOfNav>
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    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-10152">2026-08-31</dei:DocumentPeriodEndDate>
    <oef:MaterialFundChngNoticeTextBlock contextRef="C000201533_ClassMember" id="ixv-10156">This report describes changes to the Fund that occurred during the reporting period.</oef:MaterialFundChngNoticeTextBlock>
    <oef:FundName contextRef="C000201533_ClassMember" id="ixv-10167">Fidelity&#xae; SAI Total Bond Fund</oef:FundName>
    <oef:ClassName contextRef="C000201533_ClassMember" id="ixv-10170">Fidelity&#xae; SAI Total Bond Fund</oef:ClassName>
    <dei:TradingSymbol contextRef="C000201533_ClassMember" id="ixv-10174">FSMTX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000201533_ClassMember" id="ixv-10193">This annual shareholder report contains information about Fidelity&#xae; SAI Total Bond Fund for the period September 1, 2025 to August 31, 2026.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000201533_ClassMember" id="ixv-10195">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000201533_ClassMember" id="ixv-10200">You can find additional information about the Fund at fundresearch.fidelity.com/prospectus/sec. You can also request this information by contacting us at 1-800-544-3455 or by sending an e-mail to fidfunddocuments@fidelity.com.</oef:AddlInfoTextBlock>
    <oef:AddlInfoWebsite contextRef="C000201533_ClassMember" id="ixv-10202">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000201533_ClassMember" id="ixv-10205">1-800-544-3455</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000201533_ClassMember" id="ixv-10208">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000201533_ClassMember" id="ixv-10215">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What were your Fund costs for the last year?&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(based on hypothetical $10,000 investment)&lt;/span&gt;&lt;/div&gt;
&lt;div&gt;&lt;span style="font-size:11px;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:bold;"&gt;FUND COST (PREVIOUS YEAR)&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;table cellpadding="0" cellspacing="0" style="border-collapse:collapse;border-style:none;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:51%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:21%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;Costs of a $10,000 investment&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:27%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;Costs paid as a percentage of a $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:51%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity&#xae; SAI Total Bond Fund&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:21%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;29&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:27%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;0.29&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:ExpensesTextBlock>
    <oef:ExpensesPaidAmt
      contextRef="C000201533_ClassMember"
      decimals="0"
      id="ixv-354409"
      unitRef="usd">29</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000201533_ClassMember"
      decimals="INF"
      id="ixv-354410"
      unitRef="pure">0.0029</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000201533_ClassMember" id="ixv-10258">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What affected the Fund's performance this period?&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;U.S. taxable investment-grade bonds achieved a gain for the 12 months ending August 31, 2026, buoyed by three policy interest-rate cuts by the Federal Reserve in late 2025, but pulled down since then by rising bond yields amid higher consumer inflation, a resilient economy and heavy U.S. Treasury issuance.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Against this backdrop, allocations to "plus sectors", led by high-yield bonds, emerging-markets debt and global bonds, notably contributed to the fund's performance versus the benchmark Bloomberg U.S. Aggregate Index for the fiscal year.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Non-benchmark exposure to leveraged loans and high-yield commercial mortgage-backed securities also provided a boost to performance versus the benchmark.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Among investment-grade bonds, overweight holdings and investment choices among asset-backed securities, particularly collateralized loan obligations, and commercial mortgage-backed securities each added modest value.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;In contrast, underweight holdings in investment-grade corporate bonds, particularly below-benchmark exposure to industrials, detracted from the fund's relative performance.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;An underweight in mortgage-backed securities modestly hurt as well.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Notable changes over the past 12 months included management's decision to gradually lower the fund's overall risk profile by slightly reducing exposure to investment-grade corporate bonds and increasing the allocation to mortgage-backed securities in the second half of the period.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:FactorsAffectingPerfTextBlock>
    <oef:LineGraphTableTextBlock contextRef="C000201533_ClassMember" id="ixv-10285">How did the Fund perform over the life of Fund?

 &#160;&#160;
CUMULATIVE PERFORMANCE
October 25, 2018 through August 31, 2026. 
Initial investment of $10,000.
Fidelity&#xae; SAI Total Bond Fund


$10,000

$11,067


$11,859


$12,193


$10,847


$10,891


$11,836


$12,328


$12,586



Bloomberg U.S. Aggregate Bond Index


$10,000

$11,154


$11,876


$11,866


$10,499


$10,374


$11,131


$11,480


$11,697



&#160;

2018

2019

2020

2021

2022

2023

2024

2025

2026









&#160;
</oef:LineGraphTableTextBlock>
    <oef:LineGraphAndTableMeasureName contextRef="C000201533_LG_ClassMember_9YR" id="ixv-10304">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity&#xae; SAI Total Bond Fund&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000201533_ClassMember_AsOf_2018"
      decimals="0"
      id="ixv-354411"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000201533_ClassMember_AsOf_2019"
      decimals="0"
      id="ixv-354412"
      unitRef="usd">11067</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000201533_ClassMember_AsOf_2020"
      decimals="0"
      id="ixv-354413"
      unitRef="usd">11859</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000201533_ClassMember_AsOf_2021"
      decimals="0"
      id="ixv-354414"
      unitRef="usd">12193</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000201533_ClassMember_AsOf_2022"
      decimals="0"
      id="ixv-354415"
      unitRef="usd">10847</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000201533_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-354416"
      unitRef="usd">10891</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000201533_ClassMember_AsOf_2024"
      decimals="0"
      id="ixv-354417"
      unitRef="usd">11836</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000201533_ClassMember_AsOf_2025"
      decimals="0"
      id="ixv-354418"
      unitRef="usd">12328</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000201533_ClassMember_AsOf_2026"
      decimals="0"
      id="ixv-354419"
      unitRef="usd">12586</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000201533_LG_1_AdditionalIndexMember_9YR"
      id="ixv-10345">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg U.S. Aggregate Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000201533_1_AdditionalIndexMember_AsOf_2018"
      decimals="0"
      id="ixv-354420"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000201533_1_AdditionalIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-354421"
      unitRef="usd">11154</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000201533_1_AdditionalIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-354422"
      unitRef="usd">11876</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000201533_1_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-354423"
      unitRef="usd">11866</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000201533_1_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-354424"
      unitRef="usd">10499</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000201533_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-354425"
      unitRef="usd">10374</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000201533_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-354426"
      unitRef="usd">11131</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000201533_1_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-354427"
      unitRef="usd">11480</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000201533_1_AdditionalIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-354428"
      unitRef="usd">11697</oef:AccmVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000201533_ClassMember" id="ixv-10432">AVERAGE ANNUAL TOTAL RETURNS:

&#160;

1 Year

5 Year

Life of Fund&#160;A


Fidelity&#xae; SAI Total Bond Fund

2.09%

0.64%

2.97%


Bloomberg U.S. Aggregate Bond Index

1.89%


-0.29%


2.02%




A&#160; &#160;From October 25, 2018

&#160;
Visit www.fidelity.com for more recent performance information.&#160;

&#160;


The Fund's past performance is not a good predictor of the Fund's future performance. &#160;The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.





</oef:AvgAnnlRtrTableTextBlock>
    <oef:AvgAnnlRtrPct
      contextRef="C000201533_NoLoadClassMember_1YR"
      decimals="INF"
      id="ixv-354429"
      unitRef="pure">0.0209</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000201533_NoLoadClassMember_5YR"
      decimals="INF"
      id="ixv-354430"
      unitRef="pure">0.0064</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000201533_NoLoadClassMember_2025-09-01_2026-08-31"
      decimals="INF"
      id="ixv-354431"
      unitRef="pure">0.0297</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000201533_0_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-354432"
      unitRef="pure">0.0189</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000201533_0_BBIndexMember_5YR"
      decimals="INF"
      id="ixv-354433"
      unitRef="pure">-0.0029</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000201533_0_BBIndexMember_LOC"
      decimals="INF"
      id="ixv-354434"
      unitRef="pure">0.0202</oef:AvgAnnlRtrPct>
    <oef:PerfInceptionDate
      contextRef="C000201533_Perf_2018-10-25_ClassMember"
      id="ixv-10487">2018-10-25</oef:PerfInceptionDate>
    <oef:UpdPerfInfoLocationTextBlock contextRef="C000201533_ClassMember" id="ixv-10497">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Visit &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;www.fidelity.com&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt; for more recent performance information.&lt;/span&gt;</oef:UpdPerfInfoLocationTextBlock>
    <oef:PerformancePastDoesNotIndicateFuture contextRef="C000201533_ClassMember" id="ixv-10509">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:italic;font-weight:normal;"&gt;The Fund's past performance is not a good predictor of the Fund's future performance.&lt;/span&gt;</oef:PerformancePastDoesNotIndicateFuture>
    <oef:NoDeductionOfTaxesTextBlock contextRef="C000201533_ClassMember" id="ixv-10513">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.&lt;/span&gt;</oef:NoDeductionOfTaxesTextBlock>
    <oef:AddlFundStatisticsTextBlock contextRef="C000201533_ClassMember" id="ixv-10519">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;Key Fund Statistics&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(as of August 31, 2026)&lt;/span&gt;&lt;/div&gt;
&lt;div&gt;&lt;span style="font-size:11px;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;table cellpadding="0" cellspacing="1" style="border-collapse:separate;border-style:none;margin:auto;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:63%; " valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:bold;"&gt;KEY FACTS&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt; &lt;span&gt;&#160;&lt;/span&gt;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fund Size&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;22,131,253,996&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;6,330&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;62,387,360&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="middle"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Portfolio Turnover&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;154&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:AddlFundStatisticsTextBlock>
    <us-gaap:AssetsNet
      contextRef="C000201533_InstantMember"
      decimals="0"
      id="ixv-354435"
      unitRef="usd">22131253996</us-gaap:AssetsNet>
    <oef:HoldingsCount
      contextRef="C000201533_InstantMember"
      decimals="INF"
      id="ixv-354436"
      unitRef="holding">6330</oef:HoldingsCount>
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      contextRef="C000201533_ClassMember"
      decimals="0"
      id="ixv-354437"
      unitRef="usd">62387360</oef:AdvisoryFeesPaidAmt>
    <us-gaap:InvestmentCompanyPortfolioTurnover
      contextRef="C000201533_ClassMember"
      decimals="INF"
      id="ixv-354438"
      unitRef="pure">1.54</us-gaap:InvestmentCompanyPortfolioTurnover>
    <oef:HoldingsTableTextBlock contextRef="C000201533_ClassMember" id="ixv-10594">
&#160;
U.S. Government and U.S. Government Agency Obligations

55.4


AAA

5.6


AA

0.7


A

6.8


BBB

14.4


BB

4.0


B

5.0


CCC,CC,C

1.0


D

0.0


Not Rated

8.9


Equities

0.1




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

U.S. Government and U.S. Government Agency Obligations - 55.4


&#160;

AAA - 5.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

AA - 0.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

A - 6.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BBB - 14.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BB - 4.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

B - 5.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

CCC,CC,C - 1.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

D - 0.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Not Rated - 8.9&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Equities - 0.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


Short-Term Investments and Net Other Assets (Liabilities) - (1.9)% 


&#160;


We have used ratings from Moody's Investors Service, Inc. Where Moody's&#xae; ratings are not available, we have used S&amp;P&#xae; ratings. All ratings are as of the date indicated and do not reflect subsequent changes.




&#160;
&#160;
&#160;
&#160;
U.S. Treasury Obligations

39.5


Corporate Bonds

23.0


U.S. Government Agency - Mortgage Securities

15.9


Asset-Backed Securities

8.5


CMOs and Other Mortgage Related Securities

7.8


Bank Loan Obligations

5.4


Foreign Government and Government Agency Obligations

1.3


Preferred Securities

0.3


Common Stocks

0.1


Other Investments

0.1


Preferred Stocks

0.0


Options

0.0




ASSET ALLOCATION (% of Fund's net assets)


&#160;



&#160;

U.S. Treasury Obligations - 39.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Corporate Bonds - 23.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

U.S. Government Agency - Mortgage Securities - 15.9


&#160;

Asset-Backed Securities - 8.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

CMOs and Other Mortgage Related Securities - 7.8


&#160;

Bank Loan Obligations - 5.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Foreign Government and Government Agency Obligations - 1.3


&#160;

Preferred Securities - 0.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Common Stocks - 0.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Other Investments - 0.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Preferred Stocks - 0.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Options - 0.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


Short-Term Investments and Net Other Assets (Liabilities) - (1.9)%


&#160;






United States

87.7


Grand Cayman (UK Overseas Ter)

4.4


United Kingdom

1.2


Mexico

1.1


Bailiwick Of Jersey

0.7


Germany

0.7


Ireland

0.6


France

0.5


Canada

0.4


Others

2.7




GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

United States - 87.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Grand Cayman (UK Overseas Ter) - 4.4&#160;&#160;&#160;&#160;


&#160;

United Kingdom - 1.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Mexico - 1.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Bailiwick Of Jersey - 0.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Germany - 0.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Ireland - 0.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

France - 0.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Canada - 0.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Others - 2.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;




&#160;




&#160;
&#160;
</oef:HoldingsTableTextBlock>
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      contextRef="C000201533_QD_USGovernmentandUSGovernmentAgencyObligations_Member"
      decimals="INF"
      id="ixv-354439"
      unitRef="pure">0.554</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000201533_QD_AAA_Member"
      decimals="INF"
      id="ixv-354440"
      unitRef="pure">0.056</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-354441"
      unitRef="pure">0.007</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000201533_QD_A_Member"
      decimals="INF"
      id="ixv-354442"
      unitRef="pure">0.068</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000201533_QD_BBB_Member"
      decimals="INF"
      id="ixv-354443"
      unitRef="pure">0.144</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000201533_QD_BB_Member"
      decimals="INF"
      id="ixv-354444"
      unitRef="pure">0.040</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000201533_QD_B_Member"
      decimals="INF"
      id="ixv-354445"
      unitRef="pure">0.050</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000201533_QD_CCCCCC_Member"
      decimals="INF"
      id="ixv-354446"
      unitRef="pure">0.010</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000201533_QD_D_Member"
      decimals="INF"
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      unitRef="pure">0.000</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000201533_QD_NotRated_Member"
      decimals="INF"
      id="ixv-354448"
      unitRef="pure">0.089</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000201533_QD_Equities_Member"
      decimals="INF"
      id="ixv-354449"
      unitRef="pure">0.001</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000201533_AA_USTreasuryObligations_Member"
      decimals="INF"
      id="ixv-354450"
      unitRef="pure">0.395</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000201533_AA_CorporateBonds_Member"
      decimals="INF"
      id="ixv-354451"
      unitRef="pure">0.230</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000201533_AA_USGovernmentAgencyMortgageSecurities_Member"
      decimals="INF"
      id="ixv-354452"
      unitRef="pure">0.159</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000201533_AA_AssetBackedSecurities_Member"
      decimals="INF"
      id="ixv-354453"
      unitRef="pure">0.085</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000201533_AA_CMOsandOtherMortgageRelatedSecurities_Member"
      decimals="INF"
      id="ixv-354454"
      unitRef="pure">0.078</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-354455"
      unitRef="pure">0.054</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-354456"
      unitRef="pure">0.013</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000201533_AA_PreferredSecurities_Member"
      decimals="INF"
      id="ixv-354457"
      unitRef="pure">0.003</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000201533_AA_CommonStocks_Member"
      decimals="INF"
      id="ixv-354458"
      unitRef="pure">0.001</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000201533_AA_OtherInvestments_Member"
      decimals="INF"
      id="ixv-354459"
      unitRef="pure">0.001</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000201533_AA_PreferredStocks_Member"
      decimals="INF"
      id="ixv-354460"
      unitRef="pure">0.000</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000201533_AA_Options_Member"
      decimals="INF"
      id="ixv-354461"
      unitRef="pure">0.000</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000201533_GD_US_Member"
      decimals="INF"
      id="ixv-354462"
      unitRef="pure">0.877</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000201533_GD_GrandCaymanUKOverseasTer_Member"
      decimals="INF"
      id="ixv-354463"
      unitRef="pure">0.044</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000201533_GD_GB_Member"
      decimals="INF"
      id="ixv-354464"
      unitRef="pure">0.012</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000201533_GD_MX_Member"
      decimals="INF"
      id="ixv-354465"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000201533_GD_BailiwickOfJersey_Member"
      decimals="INF"
      id="ixv-354466"
      unitRef="pure">0.007</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000201533_GD_DE_Member"
      decimals="INF"
      id="ixv-354467"
      unitRef="pure">0.007</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000201533_GD_IE_Member"
      decimals="INF"
      id="ixv-354468"
      unitRef="pure">0.006</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000201533_GD_FR_Member"
      decimals="INF"
      id="ixv-354469"
      unitRef="pure">0.005</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000201533_GD_CA_Member"
      decimals="INF"
      id="ixv-354470"
      unitRef="pure">0.004</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000201533_GD_Other_Member"
      decimals="INF"
      id="ixv-354471"
      unitRef="pure">0.027</oef:PctOfNav>
    <oef:LargestHoldingsTableTextBlock contextRef="C000201533_ClassMember" id="ixv-11128">TOP HOLDINGS(% of Fund's net assets)

&#160;

&#160;


US Treasury Notes

27.6


&#160;


US Treasury Bonds

11.9


&#160;


Fannie Mae Mortgage pass-thru certificates

5.2


&#160;


Freddie Mac Gold Pool

3.7


&#160;


Ginnie Mae II Pool

3.4


&#160;


Uniform Mortgage Backed Securities

2.4


&#160;


Freddie Mac Multifamily Structured pass-thru certificates

1.6


&#160;


JPMorgan Chase &amp; Co

1.2


&#160;


Bank of America Corp

0.9


&#160;


Morgan Stanley

0.9


&#160;


&#160;

58.8

&#160;



</oef:LargestHoldingsTableTextBlock>
    <oef:PctOfNav
      contextRef="C000201533_TH_0_Member"
      decimals="INF"
      id="ixv-354472"
      unitRef="pure">0.276</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000201533_TH_1_Member"
      decimals="INF"
      id="ixv-354473"
      unitRef="pure">0.119</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000201533_TH_2_Member"
      decimals="INF"
      id="ixv-354474"
      unitRef="pure">0.052</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000201533_TH_3_Member"
      decimals="INF"
      id="ixv-354475"
      unitRef="pure">0.037</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000201533_TH_4_Member"
      decimals="INF"
      id="ixv-354476"
      unitRef="pure">0.034</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000201533_TH_5_Member"
      decimals="INF"
      id="ixv-354477"
      unitRef="pure">0.024</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000201533_TH_6_Member"
      decimals="INF"
      id="ixv-354478"
      unitRef="pure">0.016</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000201533_TH_7_Member"
      decimals="INF"
      id="ixv-354479"
      unitRef="pure">0.012</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000201533_TH_8_Member"
      decimals="INF"
      id="ixv-354480"
      unitRef="pure">0.009</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000201533_TH_9_Member"
      decimals="INF"
      id="ixv-354481"
      unitRef="pure">0.009</oef:PctOfNav>
    <oef:MaterialFundChngTextBlock contextRef="C000201533_ClassMember" id="ixv-11253">
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;How has the Fund changed?&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;This is a summary of certain changes to the Fund since September 1, 2025. For more complete information, you may review the Fund's next prospectus, which we expect to be available by October 30, 2026 at &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;fundresearch.fidelity.com/prospectus/sec&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt; or upon request at &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;1-800-544-3455&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:0px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt; or by sending an e-mail to &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;fidfunddocuments@fidelity.com&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;table cellpadding="0" cellspacing="0" style="border-collapse:collapse;border-style:none;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:50%; background-color:#ebf3e9;border-right:2px dashed #368627;padding:19px 19px 19px 19px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;The fund modified its principal investment strategies during the reporting period.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:50%; background-color:#ebf3e9;padding:19px 19px 19px 19px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:MaterialFundChngTextBlock>
    <oef:SummaryOfChngLegendTextBlock contextRef="C000201533_ClassMember" id="ixv-11259">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;This is a summary of certain changes to the Fund since September 1, 2025. For more complete information, you may review the Fund's next prospectus, which we expect to be available by October 30, 2026 at &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;fundresearch.fidelity.com/prospectus/sec&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt; or upon request at &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;1-800-544-3455&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:0px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt; or by sending an e-mail to &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;fidfunddocuments@fidelity.com&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;.&lt;/span&gt;</oef:SummaryOfChngLegendTextBlock>
    <oef:UpdProspectusWebAddress contextRef="C000201533_ClassMember" id="ixv-11261">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;fundresearch.fidelity.com/prospectus/sec&lt;/span&gt;</oef:UpdProspectusWebAddress>
    <oef:UpdProspectusPhoneNumber contextRef="C000201533_ClassMember" id="ixv-11264">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;1-800-544-3455&lt;/span&gt;</oef:UpdProspectusPhoneNumber>
    <oef:UpdProspectusEmailAddress contextRef="C000201533_ClassMember" id="ixv-11268">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;fidfunddocuments@fidelity.com&lt;/span&gt;</oef:UpdProspectusEmailAddress>
    <oef:MaterialFundChngStrategiesTextBlock contextRef="C000201533_ClassMember" id="ixv-11279">
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;The fund modified its principal investment strategies during the reporting period.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:MaterialFundChngStrategiesTextBlock>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-11337">2026-08-31</dei:DocumentPeriodEndDate>
    <oef:FundName contextRef="C000019128_ClassMember" id="ixv-11349">Fidelity&#xae; Short-Term Bond Fund</oef:FundName>
    <oef:ClassName contextRef="C000019128_ClassMember" id="ixv-11352">Fidelity&#xae; Short-Term Bond Fund</oef:ClassName>
    <dei:TradingSymbol contextRef="C000019128_ClassMember" id="ixv-11356">FSHBX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000019128_ClassMember" id="ixv-11375">This annual shareholder report contains information about Fidelity&#xae; Short-Term Bond Fund for the period September 1, 2025 to August 31, 2026.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000019128_ClassMember" id="ixv-11377">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000019128_ClassMember" id="ixv-11382">You can find additional information about the Fund at fundresearch.fidelity.com/prospectus/sec. You can also request this information by contacting us at 1-800-544-8544 or by sending an e-mail to fidfunddocuments@fidelity.com.</oef:AddlInfoTextBlock>
    <oef:AddlInfoWebsite contextRef="C000019128_ClassMember" id="ixv-11384">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000019128_ClassMember" id="ixv-11387">1-800-544-8544</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000019128_ClassMember" id="ixv-11390">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000019128_ClassMember" id="ixv-11397">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What were your Fund costs for the last year?&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(based on hypothetical $10,000 investment)&lt;/span&gt;&lt;/div&gt;
&lt;div&gt;&lt;span style="font-size:11px;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:bold;"&gt;FUND COST (PREVIOUS YEAR)&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;table cellpadding="0" cellspacing="0" style="border-collapse:collapse;border-style:none;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:51%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:21%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;Costs of a $10,000 investment&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:27%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;Costs paid as a percentage of a $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:51%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity&#xae; Short-Term Bond Fund&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:21%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;30&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:27%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;0.30&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:ExpensesTextBlock>
    <oef:ExpensesPaidAmt
      contextRef="C000019128_ClassMember"
      decimals="0"
      id="ixv-354482"
      unitRef="usd">30</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000019128_ClassMember"
      decimals="INF"
      id="ixv-354483"
      unitRef="pure">0.0030</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000019128_ClassMember" id="ixv-11440">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What affected the Fund's performance this period?&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;U.S. taxable investment-grade bonds achieved a gain for the 12 months ending August 31, 2026, buoyed by three policy interest-rate cuts by the Federal Reserve in late 2025, but pulled down since then by rising bond yields amid higher consumer inflation, a resilient economy and heavy U.S. Treasury issuance.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Against this backdrop, the fund's strategy of favoring short-term corporate bonds, while underweighting similar-duration U.S. Treasurys, contributed to its performance versus the benchmark Bloomberg U.S. 1-3 Year Government/Credit Bond Index for the fiscal year. Within corporates, debt holdings among financial institutions, especially banks, added notable value.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Non-benchmark exposure to asset-backed securities, including car loan debt and collateralized loan obligations, also meaningfully helped.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;In contrast, the fund's yield-curve positioning, including the underweighting of one-year maturities in favor of two- and three-year positions, detracted from relative performance.&#160;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;At fiscal year-end, corporates made up about 40% of fund assets, down from 41% a year ago but still notably overweight versus the benchmark average of 22%. Exposure to U.S. Treasurys stood at roughly 43% at the end of the period, up from 35% a year ago and compared with an average of about 72% for the 1-3 year benchmark. Exposure to ABS fell from roughly 18% of assets to about 12% as of August 31.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:FactorsAffectingPerfTextBlock>
    <oef:LineGraphTableTextBlock contextRef="C000019128_ClassMember" id="ixv-11461">How did the Fund perform over the past 10 years?

 &#160;&#160;
CUMULATIVE PERFORMANCE
August 31, 2016 through August 31, 2026. 
Initial investment of $10,000.
Fidelity&#xae; Short-Term Bond Fund


$10,000

$10,103


$10,124


$10,576


$10,979


$11,035


$10,573


$10,816


$11,545


$12,095


$12,406



Bloomberg U.S. 1-3 Year Government/Credit Bond Index


$10,000

$10,090


$10,106


$10,572


$10,960


$11,003


$10,565


$10,730


$11,401


$11,930


$12,251



Bloomberg U.S. Aggregate Bond Index


$10,000

$10,049


$9,944


$10,955


$11,665


$11,655


$10,313


$10,189


$10,933


$11,276


$11,489



&#160;

2016

2017

2018

2019

2020

2021

2022

2023

2024

2025

2026









&#160;
</oef:LineGraphTableTextBlock>
    <oef:LineGraphAndTableMeasureName contextRef="C000019128_LG_ClassMember_11YR" id="ixv-11480">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity&#xae; Short-Term Bond Fund&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000019128_ClassMember_AsOf_2016"
      decimals="0"
      id="ixv-354484"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019128_ClassMember_AsOf_2017"
      decimals="0"
      id="ixv-354485"
      unitRef="usd">10103</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019128_ClassMember_AsOf_2018"
      decimals="0"
      id="ixv-354486"
      unitRef="usd">10124</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019128_ClassMember_AsOf_2019"
      decimals="0"
      id="ixv-354487"
      unitRef="usd">10576</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019128_ClassMember_AsOf_2020"
      decimals="0"
      id="ixv-354488"
      unitRef="usd">10979</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019128_ClassMember_AsOf_2021"
      decimals="0"
      id="ixv-354489"
      unitRef="usd">11035</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019128_ClassMember_AsOf_2022"
      decimals="0"
      id="ixv-354490"
      unitRef="usd">10573</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019128_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-354491"
      unitRef="usd">10816</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019128_ClassMember_AsOf_2024"
      decimals="0"
      id="ixv-354492"
      unitRef="usd">11545</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019128_ClassMember_AsOf_2025"
      decimals="0"
      id="ixv-354493"
      unitRef="usd">12095</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019128_ClassMember_AsOf_2026"
      decimals="0"
      id="ixv-354494"
      unitRef="usd">12406</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000019128_LG_1_AdditionalIndexMember_11YR"
      id="ixv-11529">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg U.S. 1-3 Year Government/Credit Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000019128_1_AdditionalIndexMember_AsOf_2016"
      decimals="0"
      id="ixv-354495"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019128_1_AdditionalIndexMember_AsOf_2017"
      decimals="0"
      id="ixv-354496"
      unitRef="usd">10090</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019128_1_AdditionalIndexMember_AsOf_2018"
      decimals="0"
      id="ixv-354497"
      unitRef="usd">10106</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019128_1_AdditionalIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-354498"
      unitRef="usd">10572</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019128_1_AdditionalIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-354499"
      unitRef="usd">10960</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019128_1_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-354500"
      unitRef="usd">11003</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019128_1_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-354501"
      unitRef="usd">10565</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019128_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-354502"
      unitRef="usd">10730</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019128_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-354503"
      unitRef="usd">11401</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019128_1_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-354504"
      unitRef="usd">11930</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019128_1_AdditionalIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-354505"
      unitRef="usd">12251</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000019128_LG_2_AdditionalIndexMember_11YR"
      id="ixv-11578">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg U.S. Aggregate Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000019128_2_AdditionalIndexMember_AsOf_2016"
      decimals="0"
      id="ixv-354506"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019128_2_AdditionalIndexMember_AsOf_2017"
      decimals="0"
      id="ixv-354507"
      unitRef="usd">10049</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019128_2_AdditionalIndexMember_AsOf_2018"
      decimals="0"
      id="ixv-354508"
      unitRef="usd">9944</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019128_2_AdditionalIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-354509"
      unitRef="usd">10955</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019128_2_AdditionalIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-354510"
      unitRef="usd">11665</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019128_2_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-354511"
      unitRef="usd">11655</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019128_2_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-354512"
      unitRef="usd">10313</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019128_2_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-354513"
      unitRef="usd">10189</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019128_2_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-354514"
      unitRef="usd">10933</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019128_2_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-354515"
      unitRef="usd">11276</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019128_2_AdditionalIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-354516"
      unitRef="usd">11489</oef:AccmVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000019128_ClassMember" id="ixv-11679">AVERAGE ANNUAL TOTAL RETURNS:

&#160;

1 Year

5 Year

10 Year


Fidelity&#xae; Short-Term Bond Fund

2.57%

2.37%

2.18%


Bloomberg U.S. 1-3 Year Government/Credit Bond Index

2.69%


2.17%


2.05%


Bloomberg U.S. Aggregate Bond Index

1.89%


-0.29%


1.40%




&#160;
&#160;
Visit www.fidelity.com for more recent performance information.&#160;

&#160;


The Fund's past performance is not a good predictor of the Fund's future performance. &#160;The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.





</oef:AvgAnnlRtrTableTextBlock>
    <oef:AvgAnnlRtrPct
      contextRef="C000019128_NoLoadClassMember_1YR"
      decimals="INF"
      id="ixv-354517"
      unitRef="pure">0.0257</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019128_NoLoadClassMember_5YR"
      decimals="INF"
      id="ixv-354518"
      unitRef="pure">0.0237</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019128_NoLoadClassMember_10YR"
      decimals="INF"
      id="ixv-354519"
      unitRef="pure">0.0218</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019128_0_AdditionalIndexMember_1YR"
      decimals="INF"
      id="ixv-354520"
      unitRef="pure">0.0269</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019128_0_AdditionalIndexMember_5YR"
      decimals="INF"
      id="ixv-354521"
      unitRef="pure">0.0217</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019128_0_AdditionalIndexMember_10YR"
      decimals="INF"
      id="ixv-354522"
      unitRef="pure">0.0205</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019128_1_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-354523"
      unitRef="pure">0.0189</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019128_1_BBIndexMember_5YR"
      decimals="INF"
      id="ixv-354524"
      unitRef="pure">-0.0029</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019128_1_BBIndexMember_10YR"
      decimals="INF"
      id="ixv-354525"
      unitRef="pure">0.0140</oef:AvgAnnlRtrPct>
    <oef:UpdPerfInfoLocationTextBlock contextRef="C000019128_ClassMember" id="ixv-11750">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Visit &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;www.fidelity.com&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt; for more recent performance information.&lt;/span&gt;</oef:UpdPerfInfoLocationTextBlock>
    <oef:PerformancePastDoesNotIndicateFuture contextRef="C000019128_ClassMember" id="ixv-11762">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:italic;font-weight:normal;"&gt;The Fund's past performance is not a good predictor of the Fund's future performance.&lt;/span&gt;</oef:PerformancePastDoesNotIndicateFuture>
    <oef:NoDeductionOfTaxesTextBlock contextRef="C000019128_ClassMember" id="ixv-11766">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.&lt;/span&gt;</oef:NoDeductionOfTaxesTextBlock>
    <oef:AddlFundStatisticsTextBlock contextRef="C000019128_ClassMember" id="ixv-11772">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;Key Fund Statistics&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(as of August 31, 2026)&lt;/span&gt;&lt;/div&gt;
&lt;div&gt;&lt;span style="font-size:11px;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;table cellpadding="0" cellspacing="1" style="border-collapse:separate;border-style:none;margin:auto;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:63%; " valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:bold;"&gt;KEY FACTS&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt; &lt;span&gt;&#160;&lt;/span&gt;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fund Size&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;2,843,357,688&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;483&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;5,198,445&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="middle"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Portfolio Turnover&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;95&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:AddlFundStatisticsTextBlock>
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&#160;
U.S. Government and U.S. Government Agency Obligations

43.3


AAA

9.9


AA

1.2


A

21.3


BBB

16.6


BB

1.4


Not Rated

5.8


Short-Term Investments and Net Other Assets (Liabilities)

0.5




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

U.S. Government and U.S. Government Agency Obligations - 43.3


&#160;

AAA - 9.9&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

AA - 1.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

A - 21.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BBB - 16.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BB - 1.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Not Rated - 5.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Short-Term Investments and Net Other Assets (Liabilities) - 0.5


&#160;


We have used ratings from Moody's Investors Service, Inc. Where Moody's&#xae; ratings are not available, we have used S&amp;P&#xae; ratings. All ratings are as of the date indicated and do not reflect subsequent changes.




&#160;
&#160;
&#160;
&#160;
U.S. Treasury Obligations

43.1


Corporate Bonds

39.1


Asset-Backed Securities

12.3


CMOs and Other Mortgage Related Securities

4.2


Other Investments

0.4


U.S. Government Agency - Mortgage Securities

0.2


Foreign Government and Government Agency Obligations

0.2


Short-Term Investments and Net Other Assets (Liabilities)

0.5




ASSET ALLOCATION (% of Fund's net assets)


&#160;



&#160;

U.S. Treasury Obligations - 43.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Corporate Bonds - 39.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Asset-Backed Securities - 12.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

CMOs and Other Mortgage Related Securities - 4.2


&#160;

Other Investments - 0.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

U.S. Government Agency - Mortgage Securities - 0.2


&#160;

Foreign Government and Government Agency Obligations - 0.2


&#160;

Short-Term Investments and Net Other Assets (Liabilities) - 0.5


&#160;






United States

78.6


Grand Cayman (UK Overseas Ter)

4.3


United Kingdom

3.6


Canada

2.8


Germany

2.7


France

1.4


Bailiwick Of Jersey

1.2


Ireland

1.1


Japan

1.0


Others

3.3




GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

United States - 78.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Grand Cayman (UK Overseas Ter) - 4.3&#160;&#160;&#160;&#160;


&#160;

United Kingdom - 3.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Canada - 2.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Germany - 2.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

France - 1.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Bailiwick Of Jersey - 1.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Ireland - 1.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Japan - 1.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Others - 3.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;




&#160;




&#160;
&#160;
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    <oef:LargestHoldingsTableTextBlock contextRef="C000019128_ClassMember" id="ixv-12282">TOP HOLDINGS(% of Fund's net assets)

&#160;

&#160;


US Treasury Notes

43.1


&#160;


Bank of America Corp

1.4


&#160;


JPMorgan Chase &amp; Co

1.3


&#160;


Wells Fargo &amp; Co

1.2


&#160;


Goldman Sachs Group Inc/The

1.0


&#160;


Citigroup Inc

0.9


&#160;


Deutsche Bank AG/New York NY

0.9


&#160;


General Motors Financial Co Inc

0.9


&#160;


Barclays PLC

0.8


&#160;


HSBC Holdings PLC

0.8


&#160;


&#160;

52.3

&#160;



</oef:LargestHoldingsTableTextBlock>
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    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-12453">2026-08-31</dei:DocumentPeriodEndDate>
    <oef:FundName contextRef="C000257875_ClassMember" id="ixv-12465">Fidelity&#xae; SAI Enhanced Core Bond Fund</oef:FundName>
    <oef:ClassName contextRef="C000257875_ClassMember" id="ixv-12468">Fidelity&#xae; SAI Enhanced Core Bond Fund</oef:ClassName>
    <dei:TradingSymbol contextRef="C000257875_ClassMember" id="ixv-12472">FECBX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000257875_ClassMember" id="ixv-12491">This annual shareholder report contains information about Fidelity&#xae; SAI Enhanced Core Bond Fund for the period September 1, 2025 to August 31, 2026.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000257875_ClassMember" id="ixv-12493">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000257875_ClassMember" id="ixv-12498">You can find additional information about the Fund at fundresearch.fidelity.com/prospectus/sec. You can also request this information by contacting us at 1-800-544-3455 or by sending an e-mail to fidfunddocuments@fidelity.com.</oef:AddlInfoTextBlock>
    <oef:AddlInfoWebsite contextRef="C000257875_ClassMember" id="ixv-12500">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000257875_ClassMember" id="ixv-12503">1-800-544-3455</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000257875_ClassMember" id="ixv-12506">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000257875_ClassMember" id="ixv-12513">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What were your Fund costs for the last year?&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(based on hypothetical $10,000 investment)&lt;/span&gt;&lt;/div&gt;
&lt;div&gt;&lt;span style="font-size:11px;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:bold;"&gt;FUND COST (PREVIOUS YEAR)&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;table cellpadding="0" cellspacing="0" style="border-collapse:collapse;border-style:none;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:51%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:21%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;Costs of a $10,000 investment&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:27%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;Costs paid as a percentage of a $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:51%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity&#xae; SAI Enhanced Core Bond Fund&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:21%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;15&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:27%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;0.15&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:ExpensesTextBlock>
    <oef:ExpensesPaidAmt
      contextRef="C000257875_ClassMember"
      decimals="0"
      id="ixv-354566"
      unitRef="usd">15</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000257875_ClassMember"
      decimals="INF"
      id="ixv-354567"
      unitRef="pure">0.0015</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000257875_ClassMember" id="ixv-12556">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What affected the Fund's performance this period?&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;U.S. taxable investment-grade bonds achieved a gain for the 12 months ending August 31, 2026, buoyed by three policy interest-rate cuts by the Federal Reserve in late 2025, but pulled down since then by rising bond yields amid higher consumer inflation, a resilient economy and heavy U.S. Treasury issuance.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Against this backdrop, the fund's overweight holdings in corporate-backed bonds, especially among financial institutions, contributed to performance versus the benchmark Bloomberg U.S. Aggregate Index for the fiscal year.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Modest but overweight exposure to asset-backed securities, including car loan debt and credit card receivables, also contributed to the relative result. A small allocation to commercial mortgage-backed securities helped as well.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;In contrast, security selection in agency mortgage-backed securities modestly detracted from the fund's performance versus the benchmark.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;The portfolio's yield-curve positioning also hurt slightly.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;The fund utilizes a research-driven approach identifying long-term drivers of debt-security returns. The research is systematically applied alongside a proprietary portfolio construction and risk management framework to select a broadly diversified group of debt securities that may have the potential to provide a higher total return than that of the benchmark index.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;At period end, corporates made up about 33% of fund assets, unchanged from a year ago, and compared with an average of 24% for the Aggregate index. Exposure to U.S. Treasurys ticked up from approximately 38% to about 42% of assets, versus a benchmark average of 46%.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:FactorsAffectingPerfTextBlock>
    <oef:LineGraphTableTextBlock contextRef="C000257875_ClassMember" id="ixv-12583">How did the Fund perform over the life of Fund?

 &#160;&#160;
CUMULATIVE PERFORMANCE
March 18, 2025 through August 31, 2026. 
Initial investment of $10,000.
Fidelity&#xae; SAI Enhanced Core Bond Fund


$10,000

$10,245



Bloomberg U.S. Aggregate Bond Index


$10,000

$10,261



&#160;

2025

2026









&#160;
</oef:LineGraphTableTextBlock>
    <oef:LineGraphAndTableMeasureName contextRef="C000257875_LG_ClassMember_2YR" id="ixv-12602">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity&#xae; SAI Enhanced Core Bond Fund&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000257875_ClassMember_AsOf_2025"
      decimals="0"
      id="ixv-354568"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000257875_ClassMember_AsOf_2026"
      decimals="0"
      id="ixv-354569"
      unitRef="usd">10245</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000257875_LG_1_AdditionalIndexMember_2YR"
      id="ixv-12615">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg U.S. Aggregate Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000257875_1_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-354570"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000257875_1_AdditionalIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-354571"
      unitRef="usd">10261</oef:AccmVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000257875_ClassMember" id="ixv-12653">AVERAGE ANNUAL TOTAL RETURNS:

&#160;

1 Year

Life of Fund&#160;A


Fidelity&#xae; SAI Enhanced Core Bond Fund

1.96%

3.05%


Bloomberg U.S. Aggregate Bond Index

1.89%


3.11%




A&#160; &#160;From March 18, 2025

&#160;
Visit www.fidelity.com for more recent performance information.&#160;

&#160;


The Fund's past performance is not a good predictor of the Fund's future performance. &#160;The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.





</oef:AvgAnnlRtrTableTextBlock>
    <oef:AvgAnnlRtrPct
      contextRef="C000257875_NoLoadClassMember_1YR"
      decimals="INF"
      id="ixv-354572"
      unitRef="pure">0.0196</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000257875_NoLoadClassMember_2025-09-01_2026-08-31"
      decimals="INF"
      id="ixv-354573"
      unitRef="pure">0.0305</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000257875_0_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-354574"
      unitRef="pure">0.0189</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000257875_0_BBIndexMember_LOC"
      decimals="INF"
      id="ixv-354575"
      unitRef="pure">0.0311</oef:AvgAnnlRtrPct>
    <oef:PerfInceptionDate
      contextRef="C000257875_Perf_2025-03-18_ClassMember"
      id="ixv-12697">2025-03-18</oef:PerfInceptionDate>
    <oef:UpdPerfInfoLocationTextBlock contextRef="C000257875_ClassMember" id="ixv-12707">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Visit &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;www.fidelity.com&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt; for more recent performance information.&lt;/span&gt;</oef:UpdPerfInfoLocationTextBlock>
    <oef:PerformancePastDoesNotIndicateFuture contextRef="C000257875_ClassMember" id="ixv-12719">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:italic;font-weight:normal;"&gt;The Fund's past performance is not a good predictor of the Fund's future performance.&lt;/span&gt;</oef:PerformancePastDoesNotIndicateFuture>
    <oef:NoDeductionOfTaxesTextBlock contextRef="C000257875_ClassMember" id="ixv-12723">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.&lt;/span&gt;</oef:NoDeductionOfTaxesTextBlock>
    <oef:AddlFundStatisticsTextBlock contextRef="C000257875_ClassMember" id="ixv-12729">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;Key Fund Statistics&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(as of August 31, 2026)&lt;/span&gt;&lt;/div&gt;
&lt;div&gt;&lt;span style="font-size:11px;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;table cellpadding="0" cellspacing="1" style="border-collapse:separate;border-style:none;margin:auto;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:63%; " valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:bold;"&gt;KEY FACTS&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt; &lt;span&gt;&#160;&lt;/span&gt;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fund Size&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;3,909,145,921&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;826&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;5,045,933&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="middle"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Portfolio Turnover&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;287&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:AddlFundStatisticsTextBlock>
    <us-gaap:AssetsNet
      contextRef="C000257875_InstantMember"
      decimals="0"
      id="ixv-354576"
      unitRef="usd">3909145921</us-gaap:AssetsNet>
    <oef:HoldingsCount
      contextRef="C000257875_InstantMember"
      decimals="INF"
      id="ixv-354577"
      unitRef="holding">826</oef:HoldingsCount>
    <oef:AdvisoryFeesPaidAmt
      contextRef="C000257875_ClassMember"
      decimals="0"
      id="ixv-354578"
      unitRef="usd">5045933</oef:AdvisoryFeesPaidAmt>
    <us-gaap:InvestmentCompanyPortfolioTurnover
      contextRef="C000257875_ClassMember"
      decimals="INF"
      id="ixv-354579"
      unitRef="pure">2.87</us-gaap:InvestmentCompanyPortfolioTurnover>
    <oef:HoldingsTableTextBlock contextRef="C000257875_ClassMember" id="ixv-12804">
&#160;
U.S. Government and U.S. Government Agency Obligations

68.1


AAA

4.4


AA

1.4


A

15.3


BBB

17.0


BB

0.2


Not Rated

0.4




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

U.S. Government and U.S. Government Agency Obligations - 68.1


&#160;

AAA - 4.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

AA - 1.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

A - 15.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BBB - 17.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BB - 0.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Not Rated - 0.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


Short-Term Investments and Net Other Assets (Liabilities) - (6.8)% 


&#160;


We have used ratings from Moody's Investors Service, Inc. Where Moody's&#xae; ratings are not available, we have used S&amp;P&#xae; ratings. All ratings are as of the date indicated and do not reflect subsequent changes.




&#160;
&#160;
&#160;
&#160;
U.S. Treasury Obligations

41.7


Corporate Bonds

32.5


U.S. Government Agency - Mortgage Securities

26.0


Asset-Backed Securities

3.4


CMOs and Other Mortgage Related Securities

1.4


Foreign Government and Government Agency Obligations

1.2


U.S. Government Agency Obligations

0.4


Other Investments

0.1


Municipal Securities

0.1




ASSET ALLOCATION (% of Fund's net assets)


&#160;



&#160;

U.S. Treasury Obligations - 41.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Corporate Bonds - 32.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

U.S. Government Agency - Mortgage Securities - 26.0


&#160;

Asset-Backed Securities - 3.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

CMOs and Other Mortgage Related Securities - 1.4


&#160;

Foreign Government and Government Agency Obligations - 1.2


&#160;

U.S. Government Agency Obligations - 0.4


&#160;

Other Investments - 0.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Municipal Securities - 0.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


Short-Term Investments and Net Other Assets (Liabilities) - (6.8)%


&#160;






United States

91.9


United Kingdom

1.8


Japan

1.6


Canada

1.1


Mexico

0.7


Korea (South)

0.3


Spain

0.3


Australia

0.3


Germany

0.3


Others

1.7




GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

United States - 91.9&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

United Kingdom - 1.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Japan - 1.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Canada - 1.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Mexico - 0.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Korea (South) - 0.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Spain - 0.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Australia - 0.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Germany - 0.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Others - 1.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;




&#160;




&#160;
&#160;
</oef:HoldingsTableTextBlock>
    <oef:PctOfNav
      contextRef="C000257875_QD_USGovernmentandUSGovernmentAgencyObligations_Member"
      decimals="INF"
      id="ixv-354580"
      unitRef="pure">0.681</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000257875_QD_AAA_Member"
      decimals="INF"
      id="ixv-354581"
      unitRef="pure">0.044</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000257875_QD_AA_Member"
      decimals="INF"
      id="ixv-354582"
      unitRef="pure">0.014</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000257875_QD_A_Member"
      decimals="INF"
      id="ixv-354583"
      unitRef="pure">0.153</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000257875_QD_BBB_Member"
      decimals="INF"
      id="ixv-354584"
      unitRef="pure">0.170</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000257875_QD_BB_Member"
      decimals="INF"
      id="ixv-354585"
      unitRef="pure">0.002</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000257875_QD_NotRated_Member"
      decimals="INF"
      id="ixv-354586"
      unitRef="pure">0.004</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000257875_AA_USTreasuryObligations_Member"
      decimals="INF"
      id="ixv-354587"
      unitRef="pure">0.417</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000257875_AA_CorporateBonds_Member"
      decimals="INF"
      id="ixv-354588"
      unitRef="pure">0.325</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000257875_AA_USGovernmentAgencyMortgageSecurities_Member"
      decimals="INF"
      id="ixv-354589"
      unitRef="pure">0.260</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000257875_AA_AssetBackedSecurities_Member"
      decimals="INF"
      id="ixv-354590"
      unitRef="pure">0.034</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000257875_AA_CMOsandOtherMortgageRelatedSecurities_Member"
      decimals="INF"
      id="ixv-354591"
      unitRef="pure">0.014</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000257875_AA_ForeignGovernmentandGovernmentAgencyObligations_Member"
      decimals="INF"
      id="ixv-354592"
      unitRef="pure">0.012</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000257875_AA_USGovernmentAgencyObligations_Member"
      decimals="INF"
      id="ixv-354593"
      unitRef="pure">0.004</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000257875_AA_OtherInvestments_Member"
      decimals="INF"
      id="ixv-354594"
      unitRef="pure">0.001</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000257875_AA_MunicipalSecurities_Member"
      decimals="INF"
      id="ixv-354595"
      unitRef="pure">0.001</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000257875_GD_US_Member"
      decimals="INF"
      id="ixv-354596"
      unitRef="pure">0.919</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000257875_GD_GB_Member"
      decimals="INF"
      id="ixv-354597"
      unitRef="pure">0.018</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000257875_GD_JP_Member"
      decimals="INF"
      id="ixv-354598"
      unitRef="pure">0.016</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000257875_GD_CA_Member"
      decimals="INF"
      id="ixv-354599"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000257875_GD_MX_Member"
      decimals="INF"
      id="ixv-354600"
      unitRef="pure">0.007</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000257875_GD_KR_Member"
      decimals="INF"
      id="ixv-354601"
      unitRef="pure">0.003</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000257875_GD_ES_Member"
      decimals="INF"
      id="ixv-354602"
      unitRef="pure">0.003</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000257875_GD_AU_Member"
      decimals="INF"
      id="ixv-354603"
      unitRef="pure">0.003</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000257875_GD_DE_Member"
      decimals="INF"
      id="ixv-354604"
      unitRef="pure">0.003</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000257875_GD_Other_Member"
      decimals="INF"
      id="ixv-354605"
      unitRef="pure">0.017</oef:PctOfNav>
    <oef:LargestHoldingsTableTextBlock contextRef="C000257875_ClassMember" id="ixv-13247">TOP HOLDINGS(% of Fund's net assets)

&#160;

&#160;


US Treasury Notes

30.3


&#160;


Uniform Mortgage Backed Securities

13.2


&#160;


US Treasury Bonds

11.4


&#160;


Ginnie Mae II Pool

6.6


&#160;


Fannie Mae Mortgage pass-thru certificates

3.9


&#160;


Freddie Mac Gold Pool

1.7


&#160;


JPMorgan Chase &amp; Co

1.1


&#160;


Goldman Sachs Group Inc/The

1.0


&#160;


Citigroup Inc

0.8


&#160;


Bank of America Corp

0.7


&#160;


&#160;

70.7

&#160;



</oef:LargestHoldingsTableTextBlock>
    <oef:PctOfNav
      contextRef="C000257875_TH_0_Member"
      decimals="INF"
      id="ixv-354606"
      unitRef="pure">0.303</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000257875_TH_1_Member"
      decimals="INF"
      id="ixv-354607"
      unitRef="pure">0.132</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000257875_TH_2_Member"
      decimals="INF"
      id="ixv-354608"
      unitRef="pure">0.114</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000257875_TH_3_Member"
      decimals="INF"
      id="ixv-354609"
      unitRef="pure">0.066</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000257875_TH_4_Member"
      decimals="INF"
      id="ixv-354610"
      unitRef="pure">0.039</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000257875_TH_5_Member"
      decimals="INF"
      id="ixv-354611"
      unitRef="pure">0.017</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000257875_TH_6_Member"
      decimals="INF"
      id="ixv-354612"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000257875_TH_7_Member"
      decimals="INF"
      id="ixv-354613"
      unitRef="pure">0.010</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000257875_TH_8_Member"
      decimals="INF"
      id="ixv-354614"
      unitRef="pure">0.008</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000257875_TH_9_Member"
      decimals="INF"
      id="ixv-354615"
      unitRef="pure">0.007</oef:PctOfNav>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-13418">2026-08-31</dei:DocumentPeriodEndDate>
    <oef:MaterialFundChngNoticeTextBlock contextRef="C000234193_ClassMember" id="ixv-13422">This report describes changes to the Fund that occurred during the reporting period.</oef:MaterialFundChngNoticeTextBlock>
    <oef:FundName contextRef="C000234193_ClassMember" id="ixv-13433">Fidelity&#xae; Tactical Bond Fund</oef:FundName>
    <oef:ClassName contextRef="C000234193_ClassMember" id="ixv-13436">Fidelity Advisor&#xae; Tactical Bond Fund Class M</oef:ClassName>
    <dei:TradingSymbol contextRef="C000234193_ClassMember" id="ixv-13440">FTYMX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000234193_ClassMember" id="ixv-13459">This annual shareholder report contains information about Fidelity&#xae; Tactical Bond Fund for the period September 1, 2025 to August 31, 2026.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000234193_ClassMember" id="ixv-13461">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000234193_ClassMember" id="ixv-13466">You can find additional information about the Fund at fundresearch.fidelity.com/prospectus/sec. You can also request this information by contacting us at 1-877-208-0098 or by sending an e-mail to fidfunddocuments@fidelity.com.</oef:AddlInfoTextBlock>
    <oef:AddlInfoWebsite contextRef="C000234193_ClassMember" id="ixv-13468">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000234193_ClassMember" id="ixv-13471">1-877-208-0098</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000234193_ClassMember" id="ixv-13474">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000234193_ClassMember" id="ixv-13481">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What were your Fund costs for the last year?&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(based on hypothetical $10,000 investment)&lt;/span&gt;&lt;/div&gt;
&lt;div&gt;&lt;span style="font-size:11px;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:bold;"&gt;FUND COST (PREVIOUS YEAR)&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;table cellpadding="0" cellspacing="0" style="border-collapse:collapse;border-style:none;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:51%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:21%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;Costs of a $10,000 investment&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:27%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;Costs paid as a percentage of a $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:51%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;Class M&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:21%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;96&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:27%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;0.95&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:ExpensesTextBlock>
    <oef:ExpensesPaidAmt
      contextRef="C000234193_ClassMember"
      decimals="0"
      id="ixv-354616"
      unitRef="usd">96</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000234193_ClassMember"
      decimals="INF"
      id="ixv-354617"
      unitRef="pure">0.0095</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000234193_ClassMember" id="ixv-13524">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What affected the Fund's performance this period?&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;U.S. taxable investment-grade bonds achieved a gain for the 12 months ending August 31, 2026, buoyed by three policy interest-rate cuts by the Federal Reserve in late 2025, but pulled down since then by rising bond yields amid higher consumer inflation, a resilient economy and heavy U.S. Treasury issuance.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Against this backdrop, the fund's top contributors relative to its benchmark, the Bloomberg U.S. Aggregate Bond Index, for the fiscal year came from out-of-benchmark allocations to outperforming high-yield bonds, global bonds and emerging-markets debt.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Converserly, the ETF's yield-curve positioning and its longer-than-benchmark duration in a rising-rate environment detracted from performance versus the benchmark.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;An underweight in agency mortgage-backed securities also modestly hurt.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Notable changes in positioning include increased exposure to U.S. Treasurys and reduced exposure to high-yield bonds.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:FactorsAffectingPerfTextBlock>
    <oef:LineGraphTableTextBlock contextRef="C000234193_ClassMember" id="ixv-13545">How did the Fund perform over the life of Fund?

 &#160;&#160;
CUMULATIVE PERFORMANCE
February 10, 2022 through August 31, 2026. 
Initial investment of $10,000&#160;and the current sales charge was paid.
Class M


$9,600

$8,887


$8,910


$9,586


$9,888



Bloomberg U.S. Aggregate Bond Index


$10,000

$9,301


$9,190


$9,861


$10,170



&#160;

2022

2023

2024

2025

2026









&#160;
</oef:LineGraphTableTextBlock>
    <oef:LineGraphAndTableMeasureName contextRef="C000234193_LG_ClassMember_5YR" id="ixv-13566">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Class M&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000234193_ClassMember_AsOf_2022"
      decimals="0"
      id="ixv-354618"
      unitRef="usd">9600</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000234193_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-354619"
      unitRef="usd">8887</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000234193_ClassMember_AsOf_2024"
      decimals="0"
      id="ixv-354620"
      unitRef="usd">8910</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000234193_ClassMember_AsOf_2025"
      decimals="0"
      id="ixv-354621"
      unitRef="usd">9586</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000234193_ClassMember_AsOf_2026"
      decimals="0"
      id="ixv-354622"
      unitRef="usd">9888</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000234193_LG_1_AdditionalIndexMember_5YR"
      id="ixv-13591">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg U.S. Aggregate Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
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      id="ixv-354626"
      unitRef="usd">9861</oef:AccmVal>
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      id="ixv-354627"
      unitRef="usd">10170</oef:AccmVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000234193_ClassMember" id="ixv-13650">AVERAGE ANNUAL TOTAL RETURNS:

&#160;

1 Year

Life of Fund&#160;A


Class M (incl. 4.00% sales charge) &#160;

-1.84%

0.24%


Class M (without 4.00% sales charge)

2.25%

1.14%


Bloomberg U.S. Aggregate Bond Index

1.89%


0.78%




A&#160; &#160;From February 10, 2022

&#160;
Visit institutional.fidelity.com for more recent performance information.&#160;

&#160;


The Fund's past performance is not a good predictor of the Fund's future performance. &#160;The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.





</oef:AvgAnnlRtrTableTextBlock>
    <oef:AvgAnnlRtrPct
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      id="ixv-354628"
      unitRef="pure">-0.0184</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000234193_ClassMember_2025-09-01_2026-08-31"
      decimals="INF"
      id="ixv-354629"
      unitRef="pure">0.0024</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
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      decimals="INF"
      id="ixv-354630"
      unitRef="pure">0.0225</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
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      unitRef="pure">0.0114</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000234193_0_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-354632"
      unitRef="pure">0.0189</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000234193_0_BBIndexMember_LOC"
      decimals="INF"
      id="ixv-354633"
      unitRef="pure">0.0078</oef:AvgAnnlRtrPct>
    <oef:PerfInceptionDate
      contextRef="C000234193_Perf_2022-02-10_ClassMember"
      id="ixv-13706">2022-02-10</oef:PerfInceptionDate>
    <oef:UpdPerfInfoLocationTextBlock contextRef="C000234193_ClassMember" id="ixv-13716">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Visit &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;institutional.fidelity.com&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt; for more recent performance information.&lt;/span&gt;</oef:UpdPerfInfoLocationTextBlock>
    <oef:PerformancePastDoesNotIndicateFuture contextRef="C000234193_ClassMember" id="ixv-13728">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:italic;font-weight:normal;"&gt;The Fund's past performance is not a good predictor of the Fund's future performance.&lt;/span&gt;</oef:PerformancePastDoesNotIndicateFuture>
    <oef:NoDeductionOfTaxesTextBlock contextRef="C000234193_ClassMember" id="ixv-13732">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.&lt;/span&gt;</oef:NoDeductionOfTaxesTextBlock>
    <oef:AddlFundStatisticsTextBlock contextRef="C000234193_ClassMember" id="ixv-13738">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;Key Fund Statistics&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(as of August 31, 2026)&lt;/span&gt;&lt;/div&gt;
&lt;div&gt;&lt;span style="font-size:11px;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;table cellpadding="0" cellspacing="1" style="border-collapse:separate;border-style:none;margin:auto;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:63%; " valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:bold;"&gt;KEY FACTS&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt; &lt;span&gt;&#160;&lt;/span&gt;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fund Size&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;43,942,866&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;99&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;284,923&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="middle"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Portfolio Turnover&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;28&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:AddlFundStatisticsTextBlock>
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      unitRef="usd">43942866</us-gaap:AssetsNet>
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    <oef:HoldingsTableTextBlock contextRef="C000234193_ClassMember" id="ixv-13817">
&#160;
U.S. Government and U.S. Government Agency Obligations

46.1


AAA

1.2


AA

0.2


A

3.4


BBB

12.0


BB

12.3


B

11.9


CCC,CC,C

2.6


Not Rated

5.0


Equities

2.7


Short-Term Investments and Net Other Assets (Liabilities)

2.6




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

U.S. Government and U.S. Government Agency Obligations - 46.1


&#160;

AAA - 1.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

AA - 0.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

A - 3.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BBB - 12.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BB - 12.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

B - 11.9&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

CCC,CC,C - 2.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Not Rated - 5.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Equities - 2.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Short-Term Investments and Net Other Assets (Liabilities) - 2.6


&#160;


We have used ratings from Moody's Investors Service, Inc. Where Moody's&#xae; ratings are not available, we have used S&amp;P&#xae; ratings. All ratings are as of the date indicated and do not reflect subsequent changes.




&#160;
&#160;
&#160;
&#160;
U.S. Treasury Obligations

46.1


Corporate Bonds

24.6


Bank Loan Obligations

10.5


Asset-Backed Securities

5.4


Foreign Government and Government Agency Obligations

4.0


Fixed-Income Funds

2.0


CMOs and Other Mortgage Related Securities

2.0


Preferred Securities

1.5


Common Stocks

0.5


Alternative Funds

0.4


Municipal Securities

0.2


Preferred Stocks

0.2


Short-Term Investments and Net Other Assets (Liabilities)

2.6




ASSET ALLOCATION (% of Fund's net assets)


&#160;



&#160;

U.S. Treasury Obligations - 46.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Corporate Bonds - 24.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Bank Loan Obligations - 10.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Asset-Backed Securities - 5.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Foreign Government and Government Agency Obligations - 4.0


&#160;

Fixed-Income Funds - 2.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

CMOs and Other Mortgage Related Securities - 2.0


&#160;

Preferred Securities - 1.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Common Stocks - 0.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Alternative Funds - 0.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Municipal Securities - 0.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Preferred Stocks - 0.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Short-Term Investments and Net Other Assets (Liabilities) - 2.6


&#160;






United States

83.8


United Kingdom

2.5


Canada

1.8


Mexico

1.4


Brazil

1.3


Dominican Republic

1.1


Germany

1.1


France

1.0


Israel

0.9


Others

5.1




GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

United States - 83.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

United Kingdom - 2.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Canada - 1.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Mexico - 1.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Brazil - 1.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Dominican Republic - 1.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Germany - 1.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

France - 1.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Israel - 0.9&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Others - 5.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;




&#160;




&#160;
&#160;
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      decimals="INF"
      id="ixv-354657"
      unitRef="pure">0.005</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000234193_AA_AlternativeFunds_Member"
      decimals="INF"
      id="ixv-354658"
      unitRef="pure">0.004</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000234193_AA_MunicipalSecurities_Member"
      decimals="INF"
      id="ixv-354659"
      unitRef="pure">0.002</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000234193_AA_PreferredStocks_Member"
      decimals="INF"
      id="ixv-354660"
      unitRef="pure">0.002</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000234193_AA_ShortTermInvestmentsandNetOtherAssetsLiabilities_Member"
      decimals="INF"
      id="ixv-354661"
      unitRef="pure">0.026</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-354662"
      unitRef="pure">0.838</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000234193_GD_GB_Member"
      decimals="INF"
      id="ixv-354663"
      unitRef="pure">0.025</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000234193_GD_CA_Member"
      decimals="INF"
      id="ixv-354664"
      unitRef="pure">0.018</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000234193_GD_MX_Member"
      decimals="INF"
      id="ixv-354665"
      unitRef="pure">0.014</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000234193_GD_BR_Member"
      decimals="INF"
      id="ixv-354666"
      unitRef="pure">0.013</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000234193_GD_DO_Member"
      decimals="INF"
      id="ixv-354667"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000234193_GD_DE_Member"
      decimals="INF"
      id="ixv-354668"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000234193_GD_FR_Member"
      decimals="INF"
      id="ixv-354669"
      unitRef="pure">0.010</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000234193_GD_IL_Member"
      decimals="INF"
      id="ixv-354670"
      unitRef="pure">0.009</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-354671"
      unitRef="pure">0.051</oef:PctOfNav>
    <oef:LargestHoldingsTableTextBlock contextRef="C000234193_ClassMember" id="ixv-14356">TOP HOLDINGS(% of Fund's net assets)

&#160;

&#160;


US Treasury Notes

27.1


&#160;


US Treasury Bonds

19.0


&#160;


Fidelity Real Estate High Income Fund

2.0


&#160;


Domino's Pizza Master Issuer LLC

1.9


&#160;


Petroleos Mexicanos

1.4


&#160;


Dominican Republic

1.1


&#160;


Brazilian Federative Republic

1.0


&#160;


Planet Fitness Master Issuer LLC

1.0


&#160;


Charter Communications Operating LLC / Charter Communications Operating Capital

0.9


&#160;


Millicom International Cellular SA

0.8


&#160;


&#160;

56.2

&#160;



</oef:LargestHoldingsTableTextBlock>
    <oef:PctOfNav
      contextRef="C000234193_TH_0_Member"
      decimals="INF"
      id="ixv-354672"
      unitRef="pure">0.271</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000234193_TH_1_Member"
      decimals="INF"
      id="ixv-354673"
      unitRef="pure">0.190</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000234193_TH_2_Member"
      decimals="INF"
      id="ixv-354674"
      unitRef="pure">0.020</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000234193_TH_3_Member"
      decimals="INF"
      id="ixv-354675"
      unitRef="pure">0.019</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000234193_TH_4_Member"
      decimals="INF"
      id="ixv-354676"
      unitRef="pure">0.014</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000234193_TH_5_Member"
      decimals="INF"
      id="ixv-354677"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000234193_TH_6_Member"
      decimals="INF"
      id="ixv-354678"
      unitRef="pure">0.010</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000234193_TH_7_Member"
      decimals="INF"
      id="ixv-354679"
      unitRef="pure">0.010</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000234193_TH_8_Member"
      decimals="INF"
      id="ixv-354680"
      unitRef="pure">0.009</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000234193_TH_9_Member"
      decimals="INF"
      id="ixv-354681"
      unitRef="pure">0.008</oef:PctOfNav>
    <oef:MaterialFundChngTextBlock contextRef="C000234193_ClassMember" id="ixv-14481">
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;How has the Fund changed?&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;This is a summary of certain changes to the Fund since September 1, 2025. For more complete information, you may review the Fund's next prospectus, which we expect to be available by October 30, 2026 at &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;fundresearch.fidelity.com/prospectus/sec&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt; or upon request at &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;1-877-208-0098&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:0px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt; or by sending an e-mail to &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;fidfunddocuments@fidelity.com&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;table cellpadding="0" cellspacing="0" style="border-collapse:collapse;border-style:none;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:50%; background-color:#ebf3e9;border-right:2px dashed #368627;padding:19px 19px 19px 19px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;The fund added a contractual management fee waiver during the reporting period. &lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:50%; background-color:#ebf3e9;padding:19px 19px 19px 19px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:MaterialFundChngTextBlock>
    <oef:SummaryOfChngLegendTextBlock contextRef="C000234193_ClassMember" id="ixv-14487">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;This is a summary of certain changes to the Fund since September 1, 2025. For more complete information, you may review the Fund's next prospectus, which we expect to be available by October 30, 2026 at &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;fundresearch.fidelity.com/prospectus/sec&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt; or upon request at &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;1-877-208-0098&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:0px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt; or by sending an e-mail to &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;fidfunddocuments@fidelity.com&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;.&lt;/span&gt;</oef:SummaryOfChngLegendTextBlock>
    <oef:UpdProspectusWebAddress contextRef="C000234193_ClassMember" id="ixv-14489">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;fundresearch.fidelity.com/prospectus/sec&lt;/span&gt;</oef:UpdProspectusWebAddress>
    <oef:UpdProspectusPhoneNumber contextRef="C000234193_ClassMember" id="ixv-14492">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;1-877-208-0098&lt;/span&gt;</oef:UpdProspectusPhoneNumber>
    <oef:UpdProspectusEmailAddress contextRef="C000234193_ClassMember" id="ixv-14496">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;fidfunddocuments@fidelity.com&lt;/span&gt;</oef:UpdProspectusEmailAddress>
    <oef:MaterialFundChngExpensesTextBlock contextRef="C000234193_ClassMember" id="ixv-14507">
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;The fund added a contractual management fee waiver during the reporting period. &lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:MaterialFundChngExpensesTextBlock>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-14565">2026-08-31</dei:DocumentPeriodEndDate>
    <oef:MaterialFundChngNoticeTextBlock contextRef="C000234194_ClassMember" id="ixv-14569">This report describes changes to the Fund that occurred during the reporting period.</oef:MaterialFundChngNoticeTextBlock>
    <oef:FundName contextRef="C000234194_ClassMember" id="ixv-14580">Fidelity&#xae; Tactical Bond Fund</oef:FundName>
    <oef:ClassName contextRef="C000234194_ClassMember" id="ixv-14583">Fidelity Advisor&#xae; Tactical Bond Fund Class I</oef:ClassName>
    <dei:TradingSymbol contextRef="C000234194_ClassMember" id="ixv-14587">FBAHX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000234194_ClassMember" id="ixv-14606">This annual shareholder report contains information about Fidelity&#xae; Tactical Bond Fund for the period September 1, 2025 to August 31, 2026.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000234194_ClassMember" id="ixv-14608">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000234194_ClassMember" id="ixv-14613">You can find additional information about the Fund at fundresearch.fidelity.com/prospectus/sec. You can also request this information by contacting us at 1-877-208-0098 or by sending an e-mail to fidfunddocuments@fidelity.com.</oef:AddlInfoTextBlock>
    <oef:AddlInfoWebsite contextRef="C000234194_ClassMember" id="ixv-14615">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000234194_ClassMember" id="ixv-14618">1-877-208-0098</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000234194_ClassMember" id="ixv-14621">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000234194_ClassMember" id="ixv-14628">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What were your Fund costs for the last year?&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(based on hypothetical $10,000 investment)&lt;/span&gt;&lt;/div&gt;
&lt;div&gt;&lt;span style="font-size:11px;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:bold;"&gt;FUND COST (PREVIOUS YEAR)&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;table cellpadding="0" cellspacing="0" style="border-collapse:collapse;border-style:none;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:51%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:21%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;Costs of a $10,000 investment&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:27%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;Costs paid as a percentage of a $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:51%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;Class I&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:21%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;71&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:27%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;0.70&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:ExpensesTextBlock>
    <oef:ExpensesPaidAmt
      contextRef="C000234194_ClassMember"
      decimals="0"
      id="ixv-354682"
      unitRef="usd">71</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000234194_ClassMember"
      decimals="INF"
      id="ixv-354683"
      unitRef="pure">0.0070</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000234194_ClassMember" id="ixv-14671">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What affected the Fund's performance this period?&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;U.S. taxable investment-grade bonds achieved a gain for the 12 months ending August 31, 2026, buoyed by three policy interest-rate cuts by the Federal Reserve in late 2025, but pulled down since then by rising bond yields amid higher consumer inflation, a resilient economy and heavy U.S. Treasury issuance.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Against this backdrop, the fund's top contributors relative to its benchmark, the Bloomberg U.S. Aggregate Bond Index, for the fiscal year came from out-of-benchmark allocations to outperforming high-yield bonds, global bonds and emerging-markets debt.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Converserly, the ETF's yield-curve positioning and its longer-than-benchmark duration in a rising-rate environment detracted from performance versus the benchmark.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;An underweight in agency mortgage-backed securities also modestly hurt.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Notable changes in positioning include increased exposure to U.S. Treasurys and reduced exposure to high-yield bonds.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:FactorsAffectingPerfTextBlock>
    <oef:LineGraphTableTextBlock contextRef="C000234194_ClassMember" id="ixv-14692">How did the Fund perform over the life of Fund?

 &#160;&#160;
CUMULATIVE PERFORMANCE
February 10, 2022 through August 31, 2026. 
Initial investment of $10,000.
Class I


$10,000

$9,270


$9,317


$10,049


$10,381



Bloomberg U.S. Aggregate Bond Index


$10,000

$9,301


$9,190


$9,861


$10,170



&#160;

2022

2023

2024

2025

2026









&#160;
</oef:LineGraphTableTextBlock>
    <oef:LineGraphAndTableMeasureName contextRef="C000234194_LG_ClassMember_5YR" id="ixv-14711">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Class I&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000234194_ClassMember_AsOf_2022"
      decimals="0"
      id="ixv-354684"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000234194_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-354685"
      unitRef="usd">9270</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000234194_ClassMember_AsOf_2024"
      decimals="0"
      id="ixv-354686"
      unitRef="usd">9317</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000234194_ClassMember_AsOf_2025"
      decimals="0"
      id="ixv-354687"
      unitRef="usd">10049</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000234194_ClassMember_AsOf_2026"
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      unitRef="usd">10381</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000234194_LG_1_AdditionalIndexMember_5YR"
      id="ixv-14736">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg U.S. Aggregate Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
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      id="ixv-354691"
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      decimals="0"
      id="ixv-354693"
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    <oef:AvgAnnlRtrTableTextBlock contextRef="C000234194_ClassMember" id="ixv-14795">AVERAGE ANNUAL TOTAL RETURNS:

&#160;

1 Year

Life of Fund&#160;A


Class I

2.62%

1.40%


Bloomberg U.S. Aggregate Bond Index

1.89%


0.78%




A&#160; &#160;From February 10, 2022

&#160;
Visit institutional.fidelity.com for more recent performance information.&#160;

&#160;


The Fund's past performance is not a good predictor of the Fund's future performance. &#160;The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.





</oef:AvgAnnlRtrTableTextBlock>
    <oef:AvgAnnlRtrPct
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      decimals="INF"
      id="ixv-354694"
      unitRef="pure">0.0262</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000234194_NoLoadClassMember_2025-09-01_2026-08-31"
      decimals="INF"
      id="ixv-354695"
      unitRef="pure">0.0140</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000234194_0_BBIndexMember_1YR"
      decimals="INF"
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      unitRef="pure">0.0189</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
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      decimals="INF"
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      unitRef="pure">0.0078</oef:AvgAnnlRtrPct>
    <oef:PerfInceptionDate
      contextRef="C000234194_Perf_2022-02-10_ClassMember"
      id="ixv-14839">2022-02-10</oef:PerfInceptionDate>
    <oef:UpdPerfInfoLocationTextBlock contextRef="C000234194_ClassMember" id="ixv-14849">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Visit &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;institutional.fidelity.com&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt; for more recent performance information.&lt;/span&gt;</oef:UpdPerfInfoLocationTextBlock>
    <oef:PerformancePastDoesNotIndicateFuture contextRef="C000234194_ClassMember" id="ixv-14861">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:italic;font-weight:normal;"&gt;The Fund's past performance is not a good predictor of the Fund's future performance.&lt;/span&gt;</oef:PerformancePastDoesNotIndicateFuture>
    <oef:NoDeductionOfTaxesTextBlock contextRef="C000234194_ClassMember" id="ixv-14865">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.&lt;/span&gt;</oef:NoDeductionOfTaxesTextBlock>
    <oef:AddlFundStatisticsTextBlock contextRef="C000234194_ClassMember" id="ixv-14871">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;Key Fund Statistics&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(as of August 31, 2026)&lt;/span&gt;&lt;/div&gt;
&lt;div&gt;&lt;span style="font-size:11px;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;table cellpadding="0" cellspacing="1" style="border-collapse:separate;border-style:none;margin:auto;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:63%; " valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:bold;"&gt;KEY FACTS&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt; &lt;span&gt;&#160;&lt;/span&gt;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fund Size&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;43,942,866&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;99&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;284,923&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="middle"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Portfolio Turnover&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;28&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:AddlFundStatisticsTextBlock>
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      unitRef="usd">43942866</us-gaap:AssetsNet>
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    <oef:HoldingsTableTextBlock contextRef="C000234194_ClassMember" id="ixv-14950">
&#160;
U.S. Government and U.S. Government Agency Obligations

46.1


AAA

1.2


AA

0.2


A

3.4


BBB

12.0


BB

12.3


B

11.9


CCC,CC,C

2.6


Not Rated

5.0


Equities

2.7


Short-Term Investments and Net Other Assets (Liabilities)

2.6




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

U.S. Government and U.S. Government Agency Obligations - 46.1


&#160;

AAA - 1.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

AA - 0.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

A - 3.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BBB - 12.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BB - 12.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

B - 11.9&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

CCC,CC,C - 2.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Not Rated - 5.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Equities - 2.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Short-Term Investments and Net Other Assets (Liabilities) - 2.6


&#160;


We have used ratings from Moody's Investors Service, Inc. Where Moody's&#xae; ratings are not available, we have used S&amp;P&#xae; ratings. All ratings are as of the date indicated and do not reflect subsequent changes.




&#160;
&#160;
&#160;
&#160;
U.S. Treasury Obligations

46.1


Corporate Bonds

24.6


Bank Loan Obligations

10.5


Asset-Backed Securities

5.4


Foreign Government and Government Agency Obligations

4.0


Fixed-Income Funds

2.0


CMOs and Other Mortgage Related Securities

2.0


Preferred Securities

1.5


Common Stocks

0.5


Alternative Funds

0.4


Municipal Securities

0.2


Preferred Stocks

0.2


Short-Term Investments and Net Other Assets (Liabilities)

2.6




ASSET ALLOCATION (% of Fund's net assets)


&#160;



&#160;

U.S. Treasury Obligations - 46.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Corporate Bonds - 24.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Bank Loan Obligations - 10.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Asset-Backed Securities - 5.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Foreign Government and Government Agency Obligations - 4.0


&#160;

Fixed-Income Funds - 2.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

CMOs and Other Mortgage Related Securities - 2.0


&#160;

Preferred Securities - 1.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Common Stocks - 0.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Alternative Funds - 0.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Municipal Securities - 0.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Preferred Stocks - 0.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Short-Term Investments and Net Other Assets (Liabilities) - 2.6


&#160;






United States

83.8


United Kingdom

2.5


Canada

1.8


Mexico

1.4


Brazil

1.3


Dominican Republic

1.1


Germany

1.1


France

1.0


Israel

0.9


Others

5.1




GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

United States - 83.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

United Kingdom - 2.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Canada - 1.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Mexico - 1.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Brazil - 1.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Dominican Republic - 1.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Germany - 1.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

France - 1.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Israel - 0.9&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Others - 5.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;




&#160;




&#160;
&#160;
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      id="ixv-354722"
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      unitRef="pure">0.002</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000234194_AA_PreferredStocks_Member"
      decimals="INF"
      id="ixv-354724"
      unitRef="pure">0.002</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000234194_AA_ShortTermInvestmentsandNetOtherAssetsLiabilities_Member"
      decimals="INF"
      id="ixv-354725"
      unitRef="pure">0.026</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000234194_GD_US_Member"
      decimals="INF"
      id="ixv-354726"
      unitRef="pure">0.838</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000234194_GD_GB_Member"
      decimals="INF"
      id="ixv-354727"
      unitRef="pure">0.025</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000234194_GD_CA_Member"
      decimals="INF"
      id="ixv-354728"
      unitRef="pure">0.018</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000234194_GD_MX_Member"
      decimals="INF"
      id="ixv-354729"
      unitRef="pure">0.014</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000234194_GD_BR_Member"
      decimals="INF"
      id="ixv-354730"
      unitRef="pure">0.013</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000234194_GD_DO_Member"
      decimals="INF"
      id="ixv-354731"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000234194_GD_DE_Member"
      decimals="INF"
      id="ixv-354732"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000234194_GD_FR_Member"
      decimals="INF"
      id="ixv-354733"
      unitRef="pure">0.010</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000234194_GD_IL_Member"
      decimals="INF"
      id="ixv-354734"
      unitRef="pure">0.009</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000234194_GD_Other_Member"
      decimals="INF"
      id="ixv-354735"
      unitRef="pure">0.051</oef:PctOfNav>
    <oef:LargestHoldingsTableTextBlock contextRef="C000234194_ClassMember" id="ixv-15489">TOP HOLDINGS(% of Fund's net assets)

&#160;

&#160;


US Treasury Notes

27.1


&#160;


US Treasury Bonds

19.0


&#160;


Fidelity Real Estate High Income Fund

2.0


&#160;


Domino's Pizza Master Issuer LLC

1.9


&#160;


Petroleos Mexicanos

1.4


&#160;


Dominican Republic

1.1


&#160;


Brazilian Federative Republic

1.0


&#160;


Planet Fitness Master Issuer LLC

1.0


&#160;


Charter Communications Operating LLC / Charter Communications Operating Capital

0.9


&#160;


Millicom International Cellular SA

0.8


&#160;


&#160;

56.2

&#160;



</oef:LargestHoldingsTableTextBlock>
    <oef:PctOfNav
      contextRef="C000234194_TH_0_Member"
      decimals="INF"
      id="ixv-354736"
      unitRef="pure">0.271</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000234194_TH_1_Member"
      decimals="INF"
      id="ixv-354737"
      unitRef="pure">0.190</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000234194_TH_2_Member"
      decimals="INF"
      id="ixv-354738"
      unitRef="pure">0.020</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000234194_TH_3_Member"
      decimals="INF"
      id="ixv-354739"
      unitRef="pure">0.019</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000234194_TH_4_Member"
      decimals="INF"
      id="ixv-354740"
      unitRef="pure">0.014</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000234194_TH_5_Member"
      decimals="INF"
      id="ixv-354741"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000234194_TH_6_Member"
      decimals="INF"
      id="ixv-354742"
      unitRef="pure">0.010</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000234194_TH_7_Member"
      decimals="INF"
      id="ixv-354743"
      unitRef="pure">0.010</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000234194_TH_8_Member"
      decimals="INF"
      id="ixv-354744"
      unitRef="pure">0.009</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000234194_TH_9_Member"
      decimals="INF"
      id="ixv-354745"
      unitRef="pure">0.008</oef:PctOfNav>
    <oef:MaterialFundChngTextBlock contextRef="C000234194_ClassMember" id="ixv-15614">
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;How has the Fund changed?&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;This is a summary of certain changes to the Fund since September 1, 2025. For more complete information, you may review the Fund's next prospectus, which we expect to be available by October 30, 2026 at &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;fundresearch.fidelity.com/prospectus/sec&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt; or upon request at &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;1-877-208-0098&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:0px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt; or by sending an e-mail to &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;fidfunddocuments@fidelity.com&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;table cellpadding="0" cellspacing="0" style="border-collapse:collapse;border-style:none;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:50%; background-color:#ebf3e9;border-right:2px dashed #368627;padding:19px 19px 19px 19px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;The fund added a contractual management fee waiver during the reporting period. &lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:50%; background-color:#ebf3e9;padding:19px 19px 19px 19px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:MaterialFundChngTextBlock>
    <oef:SummaryOfChngLegendTextBlock contextRef="C000234194_ClassMember" id="ixv-15620">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;This is a summary of certain changes to the Fund since September 1, 2025. For more complete information, you may review the Fund's next prospectus, which we expect to be available by October 30, 2026 at &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;fundresearch.fidelity.com/prospectus/sec&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt; or upon request at &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;1-877-208-0098&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:0px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt; or by sending an e-mail to &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;fidfunddocuments@fidelity.com&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;.&lt;/span&gt;</oef:SummaryOfChngLegendTextBlock>
    <oef:UpdProspectusWebAddress contextRef="C000234194_ClassMember" id="ixv-15622">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;fundresearch.fidelity.com/prospectus/sec&lt;/span&gt;</oef:UpdProspectusWebAddress>
    <oef:UpdProspectusPhoneNumber contextRef="C000234194_ClassMember" id="ixv-15625">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;1-877-208-0098&lt;/span&gt;</oef:UpdProspectusPhoneNumber>
    <oef:UpdProspectusEmailAddress contextRef="C000234194_ClassMember" id="ixv-15629">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;fidfunddocuments@fidelity.com&lt;/span&gt;</oef:UpdProspectusEmailAddress>
    <oef:MaterialFundChngExpensesTextBlock contextRef="C000234194_ClassMember" id="ixv-15640">
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;The fund added a contractual management fee waiver during the reporting period. &lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:MaterialFundChngExpensesTextBlock>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-15698">2026-08-31</dei:DocumentPeriodEndDate>
    <oef:FundName contextRef="C000171438_ClassMember" id="ixv-15710">Fidelity&#xae; Short-Term Bond Fund</oef:FundName>
    <oef:ClassName contextRef="C000171438_ClassMember" id="ixv-15713">Fidelity Advisor&#xae; Short-Term Bond Fund Class M</oef:ClassName>
    <dei:TradingSymbol contextRef="C000171438_ClassMember" id="ixv-15717">FBNTX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000171438_ClassMember" id="ixv-15736">This annual shareholder report contains information about Fidelity&#xae; Short-Term Bond Fund for the period September 1, 2025 to August 31, 2026.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000171438_ClassMember" id="ixv-15738">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000171438_ClassMember" id="ixv-15743">You can find additional information about the Fund at fundresearch.fidelity.com/prospectus/sec. You can also request this information by contacting us at 1-877-208-0098 or by sending an e-mail to fidfunddocuments@fidelity.com.</oef:AddlInfoTextBlock>
    <oef:AddlInfoWebsite contextRef="C000171438_ClassMember" id="ixv-15745">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000171438_ClassMember" id="ixv-15748">1-877-208-0098</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000171438_ClassMember" id="ixv-15751">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000171438_ClassMember" id="ixv-15758">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What were your Fund costs for the last year?&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(based on hypothetical $10,000 investment)&lt;/span&gt;&lt;/div&gt;
&lt;div&gt;&lt;span style="font-size:11px;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:bold;"&gt;FUND COST (PREVIOUS YEAR)&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;table cellpadding="0" cellspacing="0" style="border-collapse:collapse;border-style:none;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:51%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:21%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;Costs of a $10,000 investment&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:27%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;Costs paid as a percentage of a $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:51%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;Class M&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:21%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;51&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:27%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;0.50&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:ExpensesTextBlock>
    <oef:ExpensesPaidAmt
      contextRef="C000171438_ClassMember"
      decimals="0"
      id="ixv-354746"
      unitRef="usd">51</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000171438_ClassMember"
      decimals="INF"
      id="ixv-354747"
      unitRef="pure">0.0050</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000171438_ClassMember" id="ixv-15801">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What affected the Fund's performance this period?&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;U.S. taxable investment-grade bonds achieved a gain for the 12 months ending August 31, 2026, buoyed by three policy interest-rate cuts by the Federal Reserve in late 2025, but pulled down since then by rising bond yields amid higher consumer inflation, a resilient economy and heavy U.S. Treasury issuance.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Against this backdrop, the fund's strategy of favoring short-term corporate bonds, while underweighting similar-duration U.S. Treasurys, contributed to its performance versus the benchmark Bloomberg U.S. 1-3 Year Government/Credit Bond Index for the fiscal year. Within corporates, debt holdings among financial institutions, especially banks, added notable value.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Non-benchmark exposure to asset-backed securities, including car loan debt and collateralized loan obligations, also meaningfully helped.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;In contrast, the fund's yield-curve positioning, including the underweighting of one-year maturities in favor of two- and three-year positions, detracted from relative performance.&#160;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;At fiscal year-end, corporates made up about 40% of fund assets, down from 41% a year ago but still notably overweight versus the benchmark average of 22%. Exposure to U.S. Treasurys stood at roughly 43% at the end of the period, up from 35% a year ago and compared with an average of about 72% for the 1-3 year benchmark. Exposure to ABS fell from roughly 18% of assets to about 12% as of August 31.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:FactorsAffectingPerfTextBlock>
    <oef:LineGraphTableTextBlock contextRef="C000171438_ClassMember" id="ixv-15822">How did the Fund perform over the past 10 years?

 &#160;&#160;
CUMULATIVE PERFORMANCE
August 31, 2016 through August 31, 2026. 
Initial investment of $10,000&#160;and the current sales charge was paid.
Class M


$9,850

$9,930


$9,941


$10,350


$10,735


$10,755


$10,283


$10,499


$11,182


$11,704


$11,981



Bloomberg U.S. 1-3 Year Government/Credit Bond Index


$10,000

$10,090


$10,106


$10,572


$10,960


$11,003


$10,565


$10,730


$11,401


$11,930


$12,251



Bloomberg U.S. Aggregate Bond Index


$10,000

$10,049


$9,944


$10,955


$11,665


$11,655


$10,313


$10,189


$10,933


$11,276


$11,489



&#160;

2016

2017

2018

2019

2020

2021

2022

2023

2024

2025

2026









&#160;
</oef:LineGraphTableTextBlock>
    <oef:LineGraphAndTableMeasureName contextRef="C000171438_LG_ClassMember_11YR" id="ixv-15843">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Class M&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000171438_ClassMember_AsOf_2016"
      decimals="0"
      id="ixv-354748"
      unitRef="usd">9850</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171438_ClassMember_AsOf_2017"
      decimals="0"
      id="ixv-354749"
      unitRef="usd">9930</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171438_ClassMember_AsOf_2018"
      decimals="0"
      id="ixv-354750"
      unitRef="usd">9941</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171438_ClassMember_AsOf_2019"
      decimals="0"
      id="ixv-354751"
      unitRef="usd">10350</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171438_ClassMember_AsOf_2020"
      decimals="0"
      id="ixv-354752"
      unitRef="usd">10735</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171438_ClassMember_AsOf_2021"
      decimals="0"
      id="ixv-354753"
      unitRef="usd">10755</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171438_ClassMember_AsOf_2022"
      decimals="0"
      id="ixv-354754"
      unitRef="usd">10283</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171438_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-354755"
      unitRef="usd">10499</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171438_ClassMember_AsOf_2024"
      decimals="0"
      id="ixv-354756"
      unitRef="usd">11182</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171438_ClassMember_AsOf_2025"
      decimals="0"
      id="ixv-354757"
      unitRef="usd">11704</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171438_ClassMember_AsOf_2026"
      decimals="0"
      id="ixv-354758"
      unitRef="usd">11981</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000171438_LG_1_AdditionalIndexMember_11YR"
      id="ixv-15892">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg U.S. 1-3 Year Government/Credit Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000171438_1_AdditionalIndexMember_AsOf_2016"
      decimals="0"
      id="ixv-354759"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171438_1_AdditionalIndexMember_AsOf_2017"
      decimals="0"
      id="ixv-354760"
      unitRef="usd">10090</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171438_1_AdditionalIndexMember_AsOf_2018"
      decimals="0"
      id="ixv-354761"
      unitRef="usd">10106</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171438_1_AdditionalIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-354762"
      unitRef="usd">10572</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171438_1_AdditionalIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-354763"
      unitRef="usd">10960</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171438_1_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-354764"
      unitRef="usd">11003</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171438_1_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-354765"
      unitRef="usd">10565</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171438_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-354766"
      unitRef="usd">10730</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171438_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-354767"
      unitRef="usd">11401</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171438_1_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-354768"
      unitRef="usd">11930</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171438_1_AdditionalIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-354769"
      unitRef="usd">12251</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000171438_LG_2_AdditionalIndexMember_11YR"
      id="ixv-15941">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg U.S. Aggregate Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000171438_2_AdditionalIndexMember_AsOf_2016"
      decimals="0"
      id="ixv-354770"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171438_2_AdditionalIndexMember_AsOf_2017"
      decimals="0"
      id="ixv-354771"
      unitRef="usd">10049</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171438_2_AdditionalIndexMember_AsOf_2018"
      decimals="0"
      id="ixv-354772"
      unitRef="usd">9944</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171438_2_AdditionalIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-354773"
      unitRef="usd">10955</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171438_2_AdditionalIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-354774"
      unitRef="usd">11665</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171438_2_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-354775"
      unitRef="usd">11655</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171438_2_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-354776"
      unitRef="usd">10313</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171438_2_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-354777"
      unitRef="usd">10189</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171438_2_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-354778"
      unitRef="usd">10933</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171438_2_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-354779"
      unitRef="usd">11276</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171438_2_AdditionalIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-354780"
      unitRef="usd">11489</oef:AccmVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000171438_ClassMember" id="ixv-16042">AVERAGE ANNUAL TOTAL RETURNS:

&#160;

1 Year

5 Year

10 Year


Class M (incl. 1.50% sales charge) &#160;

0.83%

1.87%


1.82%


Class M (without 1.50% sales charge)

2.37%

2.18%

1.98%


Bloomberg U.S. 1-3 Year Government/Credit Bond Index

2.69%


2.17%


2.05%


Bloomberg U.S. Aggregate Bond Index

1.89%


-0.29%


1.40%




&#160;
&#160;
Visit institutional.fidelity.com for more recent performance information.&#160;

&#160;


The Fund's past performance is not a good predictor of the Fund's future performance. &#160;The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.





</oef:AvgAnnlRtrTableTextBlock>
    <oef:AvgAnnlRtrPct
      contextRef="C000171438_ClassMember_1YR"
      decimals="INF"
      id="ixv-354781"
      unitRef="pure">0.0083</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000171438_ClassMember_5YR"
      decimals="INF"
      id="ixv-354782"
      unitRef="pure">0.0187</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000171438_ClassMember_10YR"
      decimals="INF"
      id="ixv-354783"
      unitRef="pure">0.0182</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000171438_NoLoadClassMember_1YR"
      decimals="INF"
      id="ixv-354784"
      unitRef="pure">0.0237</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000171438_NoLoadClassMember_5YR"
      decimals="INF"
      id="ixv-354785"
      unitRef="pure">0.0218</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000171438_NoLoadClassMember_10YR"
      decimals="INF"
      id="ixv-354786"
      unitRef="pure">0.0198</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000171438_0_AdditionalIndexMember_1YR"
      decimals="INF"
      id="ixv-354787"
      unitRef="pure">0.0269</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000171438_0_AdditionalIndexMember_5YR"
      decimals="INF"
      id="ixv-354788"
      unitRef="pure">0.0217</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000171438_0_AdditionalIndexMember_10YR"
      decimals="INF"
      id="ixv-354789"
      unitRef="pure">0.0205</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000171438_1_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-354790"
      unitRef="pure">0.0189</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000171438_1_BBIndexMember_5YR"
      decimals="INF"
      id="ixv-354791"
      unitRef="pure">-0.0029</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000171438_1_BBIndexMember_10YR"
      decimals="INF"
      id="ixv-354792"
      unitRef="pure">0.0140</oef:AvgAnnlRtrPct>
    <oef:UpdPerfInfoLocationTextBlock contextRef="C000171438_ClassMember" id="ixv-16128">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Visit &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;institutional.fidelity.com&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt; for more recent performance information.&lt;/span&gt;</oef:UpdPerfInfoLocationTextBlock>
    <oef:PerformancePastDoesNotIndicateFuture contextRef="C000171438_ClassMember" id="ixv-16140">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:italic;font-weight:normal;"&gt;The Fund's past performance is not a good predictor of the Fund's future performance.&lt;/span&gt;</oef:PerformancePastDoesNotIndicateFuture>
    <oef:NoDeductionOfTaxesTextBlock contextRef="C000171438_ClassMember" id="ixv-16144">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.&lt;/span&gt;</oef:NoDeductionOfTaxesTextBlock>
    <oef:AddlFundStatisticsTextBlock contextRef="C000171438_ClassMember" id="ixv-16150">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;Key Fund Statistics&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(as of August 31, 2026)&lt;/span&gt;&lt;/div&gt;
&lt;div&gt;&lt;span style="font-size:11px;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;table cellpadding="0" cellspacing="1" style="border-collapse:separate;border-style:none;margin:auto;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:63%; " valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:bold;"&gt;KEY FACTS&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt; &lt;span&gt;&#160;&lt;/span&gt;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fund Size&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;2,843,357,688&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;483&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;5,198,445&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="middle"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Portfolio Turnover&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;95&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:AddlFundStatisticsTextBlock>
    <us-gaap:AssetsNet
      contextRef="C000171438_InstantMember"
      decimals="0"
      id="ixv-354793"
      unitRef="usd">2843357688</us-gaap:AssetsNet>
    <oef:HoldingsCount
      contextRef="C000171438_InstantMember"
      decimals="INF"
      id="ixv-354794"
      unitRef="holding">483</oef:HoldingsCount>
    <oef:AdvisoryFeesPaidAmt
      contextRef="C000171438_ClassMember"
      decimals="0"
      id="ixv-354795"
      unitRef="usd">5198445</oef:AdvisoryFeesPaidAmt>
    <us-gaap:InvestmentCompanyPortfolioTurnover
      contextRef="C000171438_ClassMember"
      decimals="INF"
      id="ixv-354796"
      unitRef="pure">0.95</us-gaap:InvestmentCompanyPortfolioTurnover>
    <oef:HoldingsTableTextBlock contextRef="C000171438_ClassMember" id="ixv-16225">
&#160;
U.S. Government and U.S. Government Agency Obligations

43.3


AAA

9.9


AA

1.2


A

21.3


BBB

16.6


BB

1.4


Not Rated

5.8


Short-Term Investments and Net Other Assets (Liabilities)

0.5




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

U.S. Government and U.S. Government Agency Obligations - 43.3


&#160;

AAA - 9.9&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

AA - 1.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

A - 21.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BBB - 16.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BB - 1.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Not Rated - 5.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Short-Term Investments and Net Other Assets (Liabilities) - 0.5


&#160;


We have used ratings from Moody's Investors Service, Inc. Where Moody's&#xae; ratings are not available, we have used S&amp;P&#xae; ratings. All ratings are as of the date indicated and do not reflect subsequent changes.




&#160;
&#160;
&#160;
&#160;
U.S. Treasury Obligations

43.1


Corporate Bonds

39.1


Asset-Backed Securities

12.3


CMOs and Other Mortgage Related Securities

4.2


Other Investments

0.4


U.S. Government Agency - Mortgage Securities

0.2


Foreign Government and Government Agency Obligations

0.2


Short-Term Investments and Net Other Assets (Liabilities)

0.5




ASSET ALLOCATION (% of Fund's net assets)


&#160;



&#160;

U.S. Treasury Obligations - 43.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Corporate Bonds - 39.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Asset-Backed Securities - 12.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

CMOs and Other Mortgage Related Securities - 4.2


&#160;

Other Investments - 0.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

U.S. Government Agency - Mortgage Securities - 0.2


&#160;

Foreign Government and Government Agency Obligations - 0.2


&#160;

Short-Term Investments and Net Other Assets (Liabilities) - 0.5


&#160;






United States

78.6


Grand Cayman (UK Overseas Ter)

4.3


United Kingdom

3.6


Canada

2.8


Germany

2.7


France

1.4


Bailiwick Of Jersey

1.2


Ireland

1.1


Japan

1.0


Others

3.3




GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

United States - 78.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Grand Cayman (UK Overseas Ter) - 4.3&#160;&#160;&#160;&#160;


&#160;

United Kingdom - 3.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Canada - 2.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Germany - 2.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

France - 1.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Bailiwick Of Jersey - 1.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Ireland - 1.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Japan - 1.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Others - 3.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;




&#160;




&#160;
&#160;
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      id="ixv-354819"
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    <oef:LargestHoldingsTableTextBlock contextRef="C000171438_ClassMember" id="ixv-16660">TOP HOLDINGS(% of Fund's net assets)

&#160;

&#160;


US Treasury Notes

43.1


&#160;


Bank of America Corp

1.4


&#160;


JPMorgan Chase &amp; Co

1.3


&#160;


Wells Fargo &amp; Co

1.2


&#160;


Goldman Sachs Group Inc/The

1.0


&#160;


Citigroup Inc

0.9


&#160;


Deutsche Bank AG/New York NY

0.9


&#160;


General Motors Financial Co Inc

0.9


&#160;


Barclays PLC

0.8


&#160;


HSBC Holdings PLC

0.8


&#160;


&#160;

52.3

&#160;



</oef:LargestHoldingsTableTextBlock>
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      id="ixv-354823"
      unitRef="pure">0.431</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-354824"
      unitRef="pure">0.014</oef:PctOfNav>
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      id="ixv-354825"
      unitRef="pure">0.013</oef:PctOfNav>
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      decimals="INF"
      id="ixv-354826"
      unitRef="pure">0.012</oef:PctOfNav>
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      decimals="INF"
      id="ixv-354827"
      unitRef="pure">0.010</oef:PctOfNav>
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      decimals="INF"
      id="ixv-354828"
      unitRef="pure">0.009</oef:PctOfNav>
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      decimals="INF"
      id="ixv-354829"
      unitRef="pure">0.009</oef:PctOfNav>
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      unitRef="pure">0.009</oef:PctOfNav>
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      id="ixv-354831"
      unitRef="pure">0.008</oef:PctOfNav>
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    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-16831">2026-08-31</dei:DocumentPeriodEndDate>
    <oef:FundName contextRef="C000048836_ClassMember" id="ixv-16843">Fidelity&#xae; Intermediate Bond Fund</oef:FundName>
    <oef:ClassName contextRef="C000048836_ClassMember" id="ixv-16846">Fidelity&#xae; Intermediate Bond Fund</oef:ClassName>
    <dei:TradingSymbol contextRef="C000048836_ClassMember" id="ixv-16850">FTHRX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000048836_ClassMember" id="ixv-16869">This annual shareholder report contains information about Fidelity&#xae; Intermediate Bond Fund for the period September 1, 2025 to August 31, 2026.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000048836_ClassMember" id="ixv-16871">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000048836_ClassMember" id="ixv-16876">You can find additional information about the Fund at fundresearch.fidelity.com/prospectus/sec. You can also request this information by contacting us at 1-800-544-8544 or by sending an e-mail to fidfunddocuments@fidelity.com.</oef:AddlInfoTextBlock>
    <oef:AddlInfoWebsite contextRef="C000048836_ClassMember" id="ixv-16878">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000048836_ClassMember" id="ixv-16881">1-800-544-8544</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000048836_ClassMember" id="ixv-16884">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000048836_ClassMember" id="ixv-16891">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What were your Fund costs for the last year?&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(based on hypothetical $10,000 investment)&lt;/span&gt;&lt;/div&gt;
&lt;div&gt;&lt;span style="font-size:11px;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:bold;"&gt;FUND COST (PREVIOUS YEAR)&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;table cellpadding="0" cellspacing="0" style="border-collapse:collapse;border-style:none;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:51%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:21%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;Costs of a $10,000 investment&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:27%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;Costs paid as a percentage of a $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:51%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity&#xae; Intermediate Bond Fund&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:21%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;45&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:27%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;0.45&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:ExpensesTextBlock>
    <oef:ExpensesPaidAmt
      contextRef="C000048836_ClassMember"
      decimals="0"
      id="ixv-354833"
      unitRef="usd">45</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000048836_ClassMember"
      decimals="INF"
      id="ixv-354834"
      unitRef="pure">0.0045</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000048836_ClassMember" id="ixv-16934">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What affected the Fund's performance this period?&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;U.S. taxable investment-grade bonds achieved a gain for the 12 months ending August 31, 2026, buoyed by three policy interest-rate cuts by the Federal Reserve in late 2025, but pulled down since then by rising bond yields amid higher consumer inflation, a resilient economy and heavy U.S. Treasury issuance.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Against this backdrop, the fund's strategy of favoring intermediate-term corporate bonds, while underweighting similar-duration U.S. Treasurys, contributed to its performance versus the benchmark Bloomberg U.S. Intermediate Government/Credit Bond Index for the fiscal year. Within corporates, debt holdings among financial institutions, especially banks, added value.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Non-benchmark exposure to asset-backed securities, including car loan debt and collateralized loan obligations, also was advantageous. An out-of-benchmark allocation to commercial mortgage-backed securities helped as well.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;In contrast, the fund's yield-curve positioning detracted from relative performance.&#160;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;At period end, corporates made up 42% of fund assets, roughly equal to a year ago and notably overweight versus the benchmark average of about 29%.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Exposure to U.S. Treasurys stood at about 42% as of August 31, compared with an average of 65% for the benchmark, while exposure to ABS stood at about 11% of fund assets at the close of the fiscal year.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:FactorsAffectingPerfTextBlock>
    <oef:LineGraphTableTextBlock contextRef="C000048836_ClassMember" id="ixv-16958">How did the Fund perform over the past 10 years?

 &#160;&#160;
CUMULATIVE PERFORMANCE
August 31, 2016 through August 31, 2026. 
Initial investment of $10,000.
Fidelity&#xae; Intermediate Bond Fund


$10,000

$10,111


$10,003


$10,821


$11,490


$11,590


$10,597


$10,675


$11,453


$11,997


$12,184



Bloomberg U.S. Intermediate Government/Credit Bond Index


$10,000

$10,082


$9,980


$10,790


$11,432


$11,451


$10,512


$10,570


$11,321


$11,853


$12,066



Bloomberg U.S. Aggregate Bond Index


$10,000

$10,049


$9,944


$10,955


$11,665


$11,655


$10,313


$10,189


$10,933


$11,276


$11,489



&#160;

2016

2017

2018

2019

2020

2021

2022

2023

2024

2025

2026









&#160;
</oef:LineGraphTableTextBlock>
    <oef:LineGraphAndTableMeasureName contextRef="C000048836_LG_ClassMember_11YR" id="ixv-16977">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity&#xae; Intermediate Bond Fund&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000048836_ClassMember_AsOf_2016"
      decimals="0"
      id="ixv-354835"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000048836_ClassMember_AsOf_2017"
      decimals="0"
      id="ixv-354836"
      unitRef="usd">10111</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000048836_ClassMember_AsOf_2018"
      decimals="0"
      id="ixv-354837"
      unitRef="usd">10003</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000048836_ClassMember_AsOf_2019"
      decimals="0"
      id="ixv-354838"
      unitRef="usd">10821</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000048836_ClassMember_AsOf_2020"
      decimals="0"
      id="ixv-354839"
      unitRef="usd">11490</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000048836_ClassMember_AsOf_2021"
      decimals="0"
      id="ixv-354840"
      unitRef="usd">11590</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000048836_ClassMember_AsOf_2022"
      decimals="0"
      id="ixv-354841"
      unitRef="usd">10597</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000048836_ClassMember_AsOf_2023"
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      unitRef="usd">10675</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000048836_ClassMember_AsOf_2024"
      decimals="0"
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      unitRef="usd">11453</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000048836_ClassMember_AsOf_2025"
      decimals="0"
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    <oef:AccmVal
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    <oef:LineGraphAndTableMeasureName
      contextRef="C000048836_LG_1_AdditionalIndexMember_11YR"
      id="ixv-17026">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg U.S. Intermediate Government/Credit Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000048836_1_AdditionalIndexMember_AsOf_2016"
      decimals="0"
      id="ixv-354846"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000048836_1_AdditionalIndexMember_AsOf_2017"
      decimals="0"
      id="ixv-354847"
      unitRef="usd">10082</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000048836_1_AdditionalIndexMember_AsOf_2018"
      decimals="0"
      id="ixv-354848"
      unitRef="usd">9980</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000048836_1_AdditionalIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-354849"
      unitRef="usd">10790</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000048836_1_AdditionalIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-354850"
      unitRef="usd">11432</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000048836_1_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-354851"
      unitRef="usd">11451</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000048836_1_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-354852"
      unitRef="usd">10512</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000048836_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-354853"
      unitRef="usd">10570</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000048836_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-354854"
      unitRef="usd">11321</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000048836_1_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-354855"
      unitRef="usd">11853</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000048836_1_AdditionalIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-354856"
      unitRef="usd">12066</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000048836_LG_2_AdditionalIndexMember_11YR"
      id="ixv-17075">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg U.S. Aggregate Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000048836_2_AdditionalIndexMember_AsOf_2016"
      decimals="0"
      id="ixv-354857"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000048836_2_AdditionalIndexMember_AsOf_2017"
      decimals="0"
      id="ixv-354858"
      unitRef="usd">10049</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000048836_2_AdditionalIndexMember_AsOf_2018"
      decimals="0"
      id="ixv-354859"
      unitRef="usd">9944</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000048836_2_AdditionalIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-354860"
      unitRef="usd">10955</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000048836_2_AdditionalIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-354861"
      unitRef="usd">11665</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000048836_2_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-354862"
      unitRef="usd">11655</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000048836_2_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-354863"
      unitRef="usd">10313</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000048836_2_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-354864"
      unitRef="usd">10189</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000048836_2_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-354865"
      unitRef="usd">10933</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000048836_2_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-354866"
      unitRef="usd">11276</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000048836_2_AdditionalIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-354867"
      unitRef="usd">11489</oef:AccmVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000048836_ClassMember" id="ixv-17176">AVERAGE ANNUAL TOTAL RETURNS:

&#160;

1 Year

5 Year

10 Year


Fidelity&#xae; Intermediate Bond Fund

1.56%

1.01%

2.00%


Bloomberg U.S. Intermediate Government/Credit Bond Index

1.80%


1.05%


1.90%


Bloomberg U.S. Aggregate Bond Index

1.89%


-0.29%


1.40%




&#160;
&#160;
Visit www.fidelity.com for more recent performance information.&#160;

&#160;


The Fund's past performance is not a good predictor of the Fund's future performance. &#160;The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.





</oef:AvgAnnlRtrTableTextBlock>
    <oef:AvgAnnlRtrPct
      contextRef="C000048836_NoLoadClassMember_1YR"
      decimals="INF"
      id="ixv-354868"
      unitRef="pure">0.0156</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000048836_NoLoadClassMember_5YR"
      decimals="INF"
      id="ixv-354869"
      unitRef="pure">0.0101</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000048836_NoLoadClassMember_10YR"
      decimals="INF"
      id="ixv-354870"
      unitRef="pure">0.0200</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000048836_0_AdditionalIndexMember_1YR"
      decimals="INF"
      id="ixv-354871"
      unitRef="pure">0.0180</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000048836_0_AdditionalIndexMember_5YR"
      decimals="INF"
      id="ixv-354872"
      unitRef="pure">0.0105</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000048836_0_AdditionalIndexMember_10YR"
      decimals="INF"
      id="ixv-354873"
      unitRef="pure">0.0190</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000048836_1_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-354874"
      unitRef="pure">0.0189</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000048836_1_BBIndexMember_5YR"
      decimals="INF"
      id="ixv-354875"
      unitRef="pure">-0.0029</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000048836_1_BBIndexMember_10YR"
      decimals="INF"
      id="ixv-354876"
      unitRef="pure">0.0140</oef:AvgAnnlRtrPct>
    <oef:UpdPerfInfoLocationTextBlock contextRef="C000048836_ClassMember" id="ixv-17247">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Visit &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;www.fidelity.com&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt; for more recent performance information.&lt;/span&gt;</oef:UpdPerfInfoLocationTextBlock>
    <oef:PerformancePastDoesNotIndicateFuture contextRef="C000048836_ClassMember" id="ixv-17259">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:italic;font-weight:normal;"&gt;The Fund's past performance is not a good predictor of the Fund's future performance.&lt;/span&gt;</oef:PerformancePastDoesNotIndicateFuture>
    <oef:NoDeductionOfTaxesTextBlock contextRef="C000048836_ClassMember" id="ixv-17263">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.&lt;/span&gt;</oef:NoDeductionOfTaxesTextBlock>
    <oef:AddlFundStatisticsTextBlock contextRef="C000048836_ClassMember" id="ixv-17269">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;Key Fund Statistics&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(as of August 31, 2026)&lt;/span&gt;&lt;/div&gt;
&lt;div&gt;&lt;span style="font-size:11px;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;table cellpadding="0" cellspacing="1" style="border-collapse:separate;border-style:none;margin:auto;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:63%; " valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:bold;"&gt;KEY FACTS&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt; &lt;span&gt;&#160;&lt;/span&gt;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fund Size&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;4,878,582,840&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;684&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;13,485,794&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="middle"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Portfolio Turnover&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;48&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:AddlFundStatisticsTextBlock>
    <us-gaap:AssetsNet
      contextRef="C000048836_InstantMember"
      decimals="0"
      id="ixv-354877"
      unitRef="usd">4878582840</us-gaap:AssetsNet>
    <oef:HoldingsCount
      contextRef="C000048836_InstantMember"
      decimals="INF"
      id="ixv-354878"
      unitRef="holding">684</oef:HoldingsCount>
    <oef:AdvisoryFeesPaidAmt
      contextRef="C000048836_ClassMember"
      decimals="0"
      id="ixv-354879"
      unitRef="usd">13485794</oef:AdvisoryFeesPaidAmt>
    <us-gaap:InvestmentCompanyPortfolioTurnover
      contextRef="C000048836_ClassMember"
      decimals="INF"
      id="ixv-354880"
      unitRef="pure">0.48</us-gaap:InvestmentCompanyPortfolioTurnover>
    <oef:HoldingsTableTextBlock contextRef="C000048836_ClassMember" id="ixv-17344">
&#160;
U.S. Government and U.S. Government Agency Obligations

41.6


AAA

9.6


AA

1.4


A

17.4


BBB

22.7


BB

1.9


B

0.4


CCC,CC,C

0.1


Not Rated

4.4


Short-Term Investments and Net Other Assets (Liabilities)

0.5




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

U.S. Government and U.S. Government Agency Obligations - 41.6


&#160;

AAA - 9.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

AA - 1.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

A - 17.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BBB - 22.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BB - 1.9&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

B - 0.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

CCC,CC,C - 0.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Not Rated - 4.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Short-Term Investments and Net Other Assets (Liabilities) - 0.5


&#160;


We have used ratings from Moody's Investors Service, Inc. Where Moody's&#xae; ratings are not available, we have used S&amp;P&#xae; ratings. All ratings are as of the date indicated and do not reflect subsequent changes.




&#160;
&#160;
&#160;
&#160;
Corporate Bonds

42.0


U.S. Treasury Obligations

41.4


Asset-Backed Securities

11.0


CMOs and Other Mortgage Related Securities

4.6


Foreign Government and Government Agency Obligations

0.3


U.S. Government Agency - Mortgage Securities

0.2


Short-Term Investments and Net Other Assets (Liabilities)

0.5




ASSET ALLOCATION (% of Fund's net assets)


&#160;



&#160;

Corporate Bonds - 42.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

U.S. Treasury Obligations - 41.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Asset-Backed Securities - 11.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

CMOs and Other Mortgage Related Securities - 4.6


&#160;

Foreign Government and Government Agency Obligations - 0.3


&#160;

U.S. Government Agency - Mortgage Securities - 0.2


&#160;

Short-Term Investments and Net Other Assets (Liabilities) - 0.5


&#160;






United States

80.4


Grand Cayman (UK Overseas Ter)

4.4


United Kingdom

4.2


Canada

1.8


Germany

1.7


Bailiwick Of Jersey

1.5


Japan

1.5


Ireland

1.3


Italy

0.6


Others

2.6




GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

United States - 80.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Grand Cayman (UK Overseas Ter) - 4.4&#160;&#160;&#160;&#160;


&#160;

United Kingdom - 4.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Canada - 1.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Germany - 1.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Bailiwick Of Jersey - 1.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Japan - 1.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Ireland - 1.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Italy - 0.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Others - 2.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;




&#160;




&#160;
&#160;
</oef:HoldingsTableTextBlock>
    <oef:PctOfNav
      contextRef="C000048836_QD_USGovernmentandUSGovernmentAgencyObligations_Member"
      decimals="INF"
      id="ixv-354881"
      unitRef="pure">0.416</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000048836_QD_AAA_Member"
      decimals="INF"
      id="ixv-354882"
      unitRef="pure">0.096</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000048836_QD_AA_Member"
      decimals="INF"
      id="ixv-354883"
      unitRef="pure">0.014</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000048836_QD_A_Member"
      decimals="INF"
      id="ixv-354884"
      unitRef="pure">0.174</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000048836_QD_BBB_Member"
      decimals="INF"
      id="ixv-354885"
      unitRef="pure">0.227</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000048836_QD_BB_Member"
      decimals="INF"
      id="ixv-354886"
      unitRef="pure">0.019</oef:PctOfNav>
    <oef:PctOfNav
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      unitRef="pure">0.004</oef:PctOfNav>
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      id="ixv-354889"
      unitRef="pure">0.044</oef:PctOfNav>
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      decimals="INF"
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      id="ixv-354891"
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      id="ixv-354893"
      unitRef="pure">0.110</oef:PctOfNav>
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      contextRef="C000048836_AA_CMOsandOtherMortgageRelatedSecurities_Member"
      decimals="INF"
      id="ixv-354894"
      unitRef="pure">0.046</oef:PctOfNav>
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      id="ixv-354895"
      unitRef="pure">0.003</oef:PctOfNav>
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      contextRef="C000048836_GD_GrandCaymanUKOverseasTer_Member"
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      id="ixv-354899"
      unitRef="pure">0.044</oef:PctOfNav>
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      unitRef="pure">0.042</oef:PctOfNav>
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      id="ixv-354901"
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      id="ixv-354903"
      unitRef="pure">0.015</oef:PctOfNav>
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      decimals="INF"
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      unitRef="pure">0.015</oef:PctOfNav>
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    <oef:LargestHoldingsTableTextBlock contextRef="C000048836_ClassMember" id="ixv-17792">TOP HOLDINGS(% of Fund's net assets)

&#160;

&#160;


US Treasury Notes

41.4


&#160;


Morgan Stanley

1.4


&#160;


JPMorgan Chase &amp; Co

1.3


&#160;


Bank of America Corp

1.3


&#160;


HSBC Holdings PLC

1.2


&#160;


Wells Fargo &amp; Co

1.1


&#160;


Deutsche Bank AG/New York NY

1.0


&#160;


General Motors Financial Co Inc

0.8


&#160;


Athene Global Funding

0.7


&#160;


AerCap Ireland Capital DAC / AerCap Global Aviation Trust

0.7


&#160;


&#160;

50.9

&#160;



</oef:LargestHoldingsTableTextBlock>
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      id="ixv-354908"
      unitRef="pure">0.414</oef:PctOfNav>
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      unitRef="pure">0.014</oef:PctOfNav>
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      unitRef="pure">0.013</oef:PctOfNav>
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      decimals="INF"
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      unitRef="pure">0.013</oef:PctOfNav>
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      decimals="INF"
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      unitRef="pure">0.012</oef:PctOfNav>
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      decimals="INF"
      id="ixv-354913"
      unitRef="pure">0.011</oef:PctOfNav>
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      unitRef="pure">0.010</oef:PctOfNav>
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      decimals="INF"
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      unitRef="pure">0.008</oef:PctOfNav>
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      unitRef="pure">0.007</oef:PctOfNav>
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    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-17963">2026-08-31</dei:DocumentPeriodEndDate>
    <oef:FundName contextRef="C000200823_ClassMember" id="ixv-17975">Fidelity Flex&#xae; Conservative Income Bond Fund</oef:FundName>
    <oef:ClassName contextRef="C000200823_ClassMember" id="ixv-17978">Fidelity Flex&#xae; Conservative Income Bond Fund</oef:ClassName>
    <dei:TradingSymbol contextRef="C000200823_ClassMember" id="ixv-17982">FJTDX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000200823_ClassMember" id="ixv-18001">This annual shareholder report contains information about Fidelity Flex&#xae; Conservative Income Bond Fund for the period September 1, 2025 to August 31, 2026.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000200823_ClassMember" id="ixv-18003">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000200823_ClassMember" id="ixv-18008">You can find additional information about the Fund at fundresearch.fidelity.com/prospectus/sec. You can also request this information by contacting us at 1-800-544-3455 or by sending an e-mail to fidfunddocuments@fidelity.com.</oef:AddlInfoTextBlock>
    <oef:AddlInfoWebsite contextRef="C000200823_ClassMember" id="ixv-18010">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000200823_ClassMember" id="ixv-18013">1-800-544-3455</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000200823_ClassMember" id="ixv-18016">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000200823_ClassMember" id="ixv-18023">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What were your Fund costs for the last year?&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(based on hypothetical $10,000 investment)&lt;/span&gt;&lt;/div&gt;
&lt;div&gt;&lt;span style="font-size:11px;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:bold;"&gt;FUND COST (PREVIOUS YEAR)&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;table cellpadding="0" cellspacing="0" style="border-collapse:collapse;border-style:none;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:51%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:21%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;Costs of a $10,000 investment&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:27%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;Costs paid as a percentage of a $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:51%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity Flex&#xae; Conservative Income Bond Fund&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:21%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;0&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:6px;color:#000000;font-style:normal;vertical-align:4px;font-weight:normal;"&gt;A&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:27%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;0.00&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:6px;color:#000000;font-style:normal;vertical-align:4px;font-weight:normal;"&gt;B&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:6px;color:#000000;font-style:normal;vertical-align:4px;font-weight:normal;"&gt;A&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans Cd';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Amount represents less than $.50&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:6px;color:#000000;font-style:normal;vertical-align:4px;font-weight:normal;"&gt;B&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans Cd';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Amount represents less than 0.005%&lt;/span&gt;&lt;/div&gt;
&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:ExpensesTextBlock>
    <oef:ExpensesPaidAmt
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      decimals="0"
      id="ixv-354918"
      unitRef="usd">0</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000200823_ClassMember"
      decimals="INF"
      id="ixv-354919"
      unitRef="pure">0.0000</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000200823_ClassMember" id="ixv-18076">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What affected the Fund's performance this period?&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;U.S. taxable investment-grade bonds achieved a gain for the 12 months ending August 31, 2026, buoyed by three policy interest-rate cuts by the Federal Reserve in late 2025, but pulled down since then by rising bond yields amid higher consumer inflation, a resilient economy and heavy U.S. Treasury issuance.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Against this backdrop, the fund's strategy of holding short-term debt in high-quality corporations contributed to performance versus the all-U.S.-Treasury benchmark for the fiscal year. Within corporates, debt holdings among financial institutions, especially banks, and industrial firms, particularly in the consumer cyclical segment, added value.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Non-benchmark exposure to asset-backed securities, primarily car loan debt, also helped.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;In contrast, the fund's yield-curve positioning detracted from relative performance.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;A roughly 11% average allocation to cash - which the fund maintained for liquidity and solid interest return - also hurt.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;At period end, corporates made up about 52% of fund assets, from roughly 51% a year ago. At the same time, we increased exposure to U.S. Treasurys from about 19% to 25% of assets, while the portfolio's position in ABS was down from approximately 16% of assets to roughly 13% as of August 31.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:FactorsAffectingPerfTextBlock>
    <oef:LineGraphTableTextBlock contextRef="C000200823_ClassMember" id="ixv-18100">How did the Fund perform over the life of Fund?

 &#160;&#160;
CUMULATIVE PERFORMANCE
May 31, 2018 through August 31, 2026. 
Initial investment of $10,000.
Fidelity Flex&#xae; Conservative Income Bond Fund


$10,000

$10,066


$10,348


$10,565


$10,614


$10,637


$11,153


$11,835


$12,439



Bloomberg U.S. 3-6 Month Treasury Bill Index


$10,000

$10,050


$10,302


$10,457


$10,466


$10,495


$10,945


$11,552


$12,084



Bloomberg U.S. Aggregate Bond Index


$10,000

$10,054


$11,077


$11,794


$11,784


$10,427


$10,303


$11,055


$11,401



&#160;

2018

2019

2020

2021

2022

2023

2024

2025

2026









&#160;
</oef:LineGraphTableTextBlock>
    <oef:LineGraphAndTableMeasureName contextRef="C000200823_LG_ClassMember_9YR" id="ixv-18119">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity Flex&#xae; Conservative Income Bond Fund&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000200823_ClassMember_AsOf_2018"
      decimals="0"
      id="ixv-354920"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000200823_ClassMember_AsOf_2019"
      decimals="0"
      id="ixv-354921"
      unitRef="usd">10066</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000200823_ClassMember_AsOf_2020"
      decimals="0"
      id="ixv-354922"
      unitRef="usd">10348</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000200823_ClassMember_AsOf_2021"
      decimals="0"
      id="ixv-354923"
      unitRef="usd">10565</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000200823_ClassMember_AsOf_2022"
      decimals="0"
      id="ixv-354924"
      unitRef="usd">10614</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000200823_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-354925"
      unitRef="usd">10637</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000200823_ClassMember_AsOf_2024"
      decimals="0"
      id="ixv-354926"
      unitRef="usd">11153</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000200823_ClassMember_AsOf_2025"
      decimals="0"
      id="ixv-354927"
      unitRef="usd">11835</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000200823_ClassMember_AsOf_2026"
      decimals="0"
      id="ixv-354928"
      unitRef="usd">12439</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000200823_LG_1_AdditionalIndexMember_9YR"
      id="ixv-18160">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg U.S. 3-6 Month Treasury Bill Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000200823_1_AdditionalIndexMember_AsOf_2018"
      decimals="0"
      id="ixv-354929"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000200823_1_AdditionalIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-354930"
      unitRef="usd">10050</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000200823_1_AdditionalIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-354931"
      unitRef="usd">10302</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000200823_1_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-354932"
      unitRef="usd">10457</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000200823_1_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-354933"
      unitRef="usd">10466</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000200823_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-354934"
      unitRef="usd">10495</oef:AccmVal>
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      contextRef="C000200823_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-354935"
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    <oef:AccmVal
      contextRef="C000200823_1_AdditionalIndexMember_AsOf_2026"
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      id="ixv-354937"
      unitRef="usd">12084</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000200823_LG_2_AdditionalIndexMember_9YR"
      id="ixv-18201">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg U.S. Aggregate Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
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    <oef:AccmVal
      contextRef="C000200823_2_AdditionalIndexMember_AsOf_2020"
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      unitRef="usd">11077</oef:AccmVal>
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      id="ixv-354942"
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      id="ixv-354943"
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      contextRef="C000200823_2_AdditionalIndexMember_AsOf_2024"
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      id="ixv-354946"
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    <oef:AvgAnnlRtrTableTextBlock contextRef="C000200823_ClassMember" id="ixv-18288">AVERAGE ANNUAL TOTAL RETURNS:

&#160;

1 Year

5 Year

Life of Fund&#160;A


Fidelity Flex&#xae; Conservative Income Bond Fund

4.11%

4.06%

3.18%


Bloomberg U.S. 3-6 Month Treasury Bill Index

3.87%


3.70%


2.79%


Bloomberg U.S. Aggregate Bond Index

1.89%


-0.29%


1.83%




A&#160; &#160;From May 31, 2018

&#160;
Visit www.401k.com for more recent performance information.&#160;

&#160;


The Fund's past performance is not a good predictor of the Fund's future performance. &#160;The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.





</oef:AvgAnnlRtrTableTextBlock>
    <oef:AvgAnnlRtrPct
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      decimals="INF"
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      unitRef="pure">0.0318</oef:AvgAnnlRtrPct>
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      id="ixv-354951"
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      id="ixv-354952"
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      id="ixv-354954"
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      decimals="INF"
      id="ixv-354955"
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      id="ixv-18358">2018-05-31</oef:PerfInceptionDate>
    <oef:UpdPerfInfoLocationTextBlock contextRef="C000200823_ClassMember" id="ixv-18368">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Visit &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;www.401k.com&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt; for more recent performance information.&lt;/span&gt;</oef:UpdPerfInfoLocationTextBlock>
    <oef:PerformancePastDoesNotIndicateFuture contextRef="C000200823_ClassMember" id="ixv-18380">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:italic;font-weight:normal;"&gt;The Fund's past performance is not a good predictor of the Fund's future performance.&lt;/span&gt;</oef:PerformancePastDoesNotIndicateFuture>
    <oef:NoDeductionOfTaxesTextBlock contextRef="C000200823_ClassMember" id="ixv-18384">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.&lt;/span&gt;</oef:NoDeductionOfTaxesTextBlock>
    <oef:AddlFundStatisticsTextBlock contextRef="C000200823_ClassMember" id="ixv-18390">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;Key Fund Statistics&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(as of August 31, 2026)&lt;/span&gt;&lt;/div&gt;
&lt;div&gt;&lt;span style="font-size:11px;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;table cellpadding="0" cellspacing="1" style="border-collapse:separate;border-style:none;margin:auto;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:63%; " valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:bold;"&gt;KEY FACTS&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt; &lt;span&gt;&#160;&lt;/span&gt;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fund Size&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;801,639,412&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;356&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;0&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="middle"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Portfolio Turnover&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;61&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:AddlFundStatisticsTextBlock>
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&#160;
U.S. Government and U.S. Government Agency Obligations

25.3


AAA

12.4


AA

5.5


A

30.3


BBB

8.4


Not Rated

0.8


Short-Term Investments and Net Other Assets (Liabilities)

17.3




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

U.S. Government and U.S. Government Agency Obligations - 25.3


&#160;

AAA - 12.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

AA - 5.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

A - 30.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BBB - 8.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Not Rated - 0.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Short-Term Investments and Net Other Assets (Liabilities) - 17.3


&#160;


We have used ratings from Moody's Investors Service, Inc. Where Moody's&#xae; ratings are not available, we have used S&amp;P&#xae; ratings. All ratings are as of the date indicated and do not reflect subsequent changes.




&#160;
&#160;
&#160;
&#160;
Corporate Bonds

43.0


U.S. Treasury Obligations

25.3


Asset-Backed Securities

13.2


Other Investments

1.2


Short-Term Investments and Net Other Assets (Liabilities)

17.3




ASSET ALLOCATION (% of Fund's net assets)


&#160;



&#160;

Corporate Bonds - 43.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

U.S. Treasury Obligations - 25.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Asset-Backed Securities - 13.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Other Investments - 1.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Short-Term Investments and Net Other Assets (Liabilities) - 17.3


&#160;






United States

82.8


United Kingdom

4.6


Canada

4.6


Netherlands

2.1


Germany

2.0


Switzerland

0.9


Japan

0.7


Denmark

0.6


Australia

0.4


Others

1.3




GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

United States - 82.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

United Kingdom - 4.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Canada - 4.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Netherlands - 2.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Germany - 2.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Switzerland - 0.9&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Japan - 0.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Denmark - 0.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Australia - 0.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Others - 1.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;




&#160;




&#160;
&#160;
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      unitRef="pure">0.004</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000200823_GD_Other_Member"
      decimals="INF"
      id="ixv-354981"
      unitRef="pure">0.013</oef:PctOfNav>
    <oef:LargestHoldingsTableTextBlock contextRef="C000200823_ClassMember" id="ixv-18848">TOP HOLDINGS(% of Fund's net assets)

&#160;

&#160;


US Treasury Bill

16.2


&#160;


US Treasury Notes

9.1


&#160;


Wells Fargo &amp; Co

1.9


&#160;


JPMorgan Chase &amp; Co

1.8


&#160;


Bank of America Corp

1.7


&#160;


Goldman Sachs Group Inc/The

1.2


&#160;


Bank of Montreal

1.2


&#160;


Mitsubishi UFJ Trust &amp; Banking Corp/NY

1.1


&#160;


Royal Bank of Canada

1.0


&#160;


Morgan Stanley Bank NA

0.9


&#160;


&#160;

36.1

&#160;



</oef:LargestHoldingsTableTextBlock>
    <oef:PctOfNav
      contextRef="C000200823_TH_0_Member"
      decimals="INF"
      id="ixv-354982"
      unitRef="pure">0.162</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000200823_TH_1_Member"
      decimals="INF"
      id="ixv-354983"
      unitRef="pure">0.091</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000200823_TH_2_Member"
      decimals="INF"
      id="ixv-354984"
      unitRef="pure">0.019</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000200823_TH_3_Member"
      decimals="INF"
      id="ixv-354985"
      unitRef="pure">0.018</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000200823_TH_4_Member"
      decimals="INF"
      id="ixv-354986"
      unitRef="pure">0.017</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000200823_TH_5_Member"
      decimals="INF"
      id="ixv-354987"
      unitRef="pure">0.012</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000200823_TH_6_Member"
      decimals="INF"
      id="ixv-354988"
      unitRef="pure">0.012</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000200823_TH_7_Member"
      decimals="INF"
      id="ixv-354989"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000200823_TH_8_Member"
      decimals="INF"
      id="ixv-354990"
      unitRef="pure">0.010</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000200823_TH_9_Member"
      decimals="INF"
      id="ixv-354991"
      unitRef="pure">0.009</oef:PctOfNav>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-19019">2026-08-31</dei:DocumentPeriodEndDate>
    <oef:MaterialFundChngNoticeTextBlock contextRef="C000234192_ClassMember" id="ixv-19023">This report describes changes to the Fund that occurred during the reporting period.</oef:MaterialFundChngNoticeTextBlock>
    <oef:FundName contextRef="C000234192_ClassMember" id="ixv-19034">Fidelity&#xae; Tactical Bond Fund</oef:FundName>
    <oef:ClassName contextRef="C000234192_ClassMember" id="ixv-19037">Fidelity Advisor&#xae; Tactical Bond Fund Class C</oef:ClassName>
    <dei:TradingSymbol contextRef="C000234192_ClassMember" id="ixv-19041">FTKCX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000234192_ClassMember" id="ixv-19060">This annual shareholder report contains information about Fidelity&#xae; Tactical Bond Fund for the period September 1, 2025 to August 31, 2026.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000234192_ClassMember" id="ixv-19062">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000234192_ClassMember" id="ixv-19067">You can find additional information about the Fund at fundresearch.fidelity.com/prospectus/sec. You can also request this information by contacting us at 1-877-208-0098 or by sending an e-mail to fidfunddocuments@fidelity.com.</oef:AddlInfoTextBlock>
    <oef:AddlInfoWebsite contextRef="C000234192_ClassMember" id="ixv-19069">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000234192_ClassMember" id="ixv-19072">1-877-208-0098</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000234192_ClassMember" id="ixv-19075">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000234192_ClassMember" id="ixv-19082">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What were your Fund costs for the last year?&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(based on hypothetical $10,000 investment)&lt;/span&gt;&lt;/div&gt;
&lt;div&gt;&lt;span style="font-size:11px;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:bold;"&gt;FUND COST (PREVIOUS YEAR)&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;table cellpadding="0" cellspacing="0" style="border-collapse:collapse;border-style:none;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:51%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:21%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;Costs of a $10,000 investment&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:27%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;Costs paid as a percentage of a $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:51%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;Class C&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:21%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;171&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:27%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;1.70&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:ExpensesTextBlock>
    <oef:ExpensesPaidAmt
      contextRef="C000234192_ClassMember"
      decimals="0"
      id="ixv-354992"
      unitRef="usd">171</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000234192_ClassMember"
      decimals="INF"
      id="ixv-354993"
      unitRef="pure">0.0170</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000234192_ClassMember" id="ixv-19125">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What affected the Fund's performance this period?&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;U.S. taxable investment-grade bonds achieved a gain for the 12 months ending August 31, 2026, buoyed by three policy interest-rate cuts by the Federal Reserve in late 2025, but pulled down since then by rising bond yields amid higher consumer inflation, a resilient economy and heavy U.S. Treasury issuance.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Against this backdrop, the fund's top contributors relative to its benchmark, the Bloomberg U.S. Aggregate Bond Index, for the fiscal year came from out-of-benchmark allocations to outperforming high-yield bonds, global bonds and emerging-markets debt.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Converserly, the ETF's yield-curve positioning and its longer-than-benchmark duration in a rising-rate environment detracted from performance versus the benchmark.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;An underweight in agency mortgage-backed securities also modestly hurt.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Notable changes in positioning include increased exposure to U.S. Treasurys and reduced exposure to high-yield bonds.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:FactorsAffectingPerfTextBlock>
    <oef:LineGraphTableTextBlock contextRef="C000234192_ClassMember" id="ixv-19146">How did the Fund perform over the life of Fund?

 &#160;&#160;
CUMULATIVE PERFORMANCE
February 10, 2022 through August 31, 2026. 
Initial investment of $10,000.
Class C


$10,000

$9,210


$9,174


$9,797


$10,020



Bloomberg U.S. Aggregate Bond Index


$10,000

$9,301


$9,190


$9,861


$10,170



&#160;

2022

2023

2024

2025

2026









&#160;
</oef:LineGraphTableTextBlock>
    <oef:LineGraphAndTableMeasureName contextRef="C000234192_LG_ClassMember_5YR" id="ixv-19165">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Class C&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000234192_ClassMember_AsOf_2022"
      decimals="0"
      id="ixv-354994"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000234192_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-354995"
      unitRef="usd">9210</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000234192_ClassMember_AsOf_2024"
      decimals="0"
      id="ixv-354996"
      unitRef="usd">9174</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000234192_ClassMember_AsOf_2025"
      decimals="0"
      id="ixv-354997"
      unitRef="usd">9797</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000234192_ClassMember_AsOf_2026"
      decimals="0"
      id="ixv-354998"
      unitRef="usd">10020</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000234192_LG_1_AdditionalIndexMember_5YR"
      id="ixv-19190">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg U.S. Aggregate Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000234192_1_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-354999"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000234192_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-355000"
      unitRef="usd">9301</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000234192_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-355001"
      unitRef="usd">9190</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000234192_1_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-355002"
      unitRef="usd">9861</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000234192_1_AdditionalIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-355003"
      unitRef="usd">10170</oef:AccmVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000234192_ClassMember" id="ixv-19249">AVERAGE ANNUAL TOTAL RETURNS:

&#160;

1 Year

Life of Fund&#160;A


Class C &#160;(incl. contingent deferred sales charge)

0.62%

0.39%


Class C

1.60%

0.39%


Bloomberg U.S. Aggregate Bond Index

1.89%


0.78%




A&#160; &#160;From February 10, 2022

&#160;
Visit institutional.fidelity.com for more recent performance information.&#160;

&#160;


The Fund's past performance is not a good predictor of the Fund's future performance. &#160;The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.





</oef:AvgAnnlRtrTableTextBlock>
    <oef:AvgAnnlRtrPct
      contextRef="C000234192_ClassMember_1YR"
      decimals="INF"
      id="ixv-355004"
      unitRef="pure">0.0062</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000234192_ClassMember_2025-09-01_2026-08-31"
      decimals="INF"
      id="ixv-355005"
      unitRef="pure">0.0039</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000234192_NoLoadClassMember_1YR"
      decimals="INF"
      id="ixv-355006"
      unitRef="pure">0.0160</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000234192_NoLoadClassMember_2025-09-01_2026-08-31"
      decimals="INF"
      id="ixv-355007"
      unitRef="pure">0.0039</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000234192_0_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-355008"
      unitRef="pure">0.0189</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000234192_0_BBIndexMember_LOC"
      decimals="INF"
      id="ixv-355009"
      unitRef="pure">0.0078</oef:AvgAnnlRtrPct>
    <oef:PerfInceptionDate
      contextRef="C000234192_Perf_2022-02-10_ClassMember"
      id="ixv-19305">2022-02-10</oef:PerfInceptionDate>
    <oef:UpdPerfInfoLocationTextBlock contextRef="C000234192_ClassMember" id="ixv-19315">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Visit &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;institutional.fidelity.com&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt; for more recent performance information.&lt;/span&gt;</oef:UpdPerfInfoLocationTextBlock>
    <oef:PerformancePastDoesNotIndicateFuture contextRef="C000234192_ClassMember" id="ixv-19327">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:italic;font-weight:normal;"&gt;The Fund's past performance is not a good predictor of the Fund's future performance.&lt;/span&gt;</oef:PerformancePastDoesNotIndicateFuture>
    <oef:NoDeductionOfTaxesTextBlock contextRef="C000234192_ClassMember" id="ixv-19331">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.&lt;/span&gt;</oef:NoDeductionOfTaxesTextBlock>
    <oef:AddlFundStatisticsTextBlock contextRef="C000234192_ClassMember" id="ixv-19337">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;Key Fund Statistics&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(as of August 31, 2026)&lt;/span&gt;&lt;/div&gt;
&lt;div&gt;&lt;span style="font-size:11px;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;table cellpadding="0" cellspacing="1" style="border-collapse:separate;border-style:none;margin:auto;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:63%; " valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:bold;"&gt;KEY FACTS&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt; &lt;span&gt;&#160;&lt;/span&gt;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fund Size&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;43,942,866&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;99&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;284,923&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="middle"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Portfolio Turnover&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;28&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:AddlFundStatisticsTextBlock>
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&#160;
U.S. Government and U.S. Government Agency Obligations

46.1


AAA

1.2


AA

0.2


A

3.4


BBB

12.0


BB

12.3


B

11.9


CCC,CC,C

2.6


Not Rated

5.0


Equities

2.7


Short-Term Investments and Net Other Assets (Liabilities)

2.6




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

U.S. Government and U.S. Government Agency Obligations - 46.1


&#160;

AAA - 1.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

AA - 0.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

A - 3.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BBB - 12.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BB - 12.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

B - 11.9&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

CCC,CC,C - 2.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Not Rated - 5.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Equities - 2.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Short-Term Investments and Net Other Assets (Liabilities) - 2.6


&#160;


We have used ratings from Moody's Investors Service, Inc. Where Moody's&#xae; ratings are not available, we have used S&amp;P&#xae; ratings. All ratings are as of the date indicated and do not reflect subsequent changes.




&#160;
&#160;
&#160;
&#160;
U.S. Treasury Obligations

46.1


Corporate Bonds

24.6


Bank Loan Obligations

10.5


Asset-Backed Securities

5.4


Foreign Government and Government Agency Obligations

4.0


Fixed-Income Funds

2.0


CMOs and Other Mortgage Related Securities

2.0


Preferred Securities

1.5


Common Stocks

0.5


Alternative Funds

0.4


Municipal Securities

0.2


Preferred Stocks

0.2


Short-Term Investments and Net Other Assets (Liabilities)

2.6




ASSET ALLOCATION (% of Fund's net assets)


&#160;



&#160;

U.S. Treasury Obligations - 46.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Corporate Bonds - 24.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Bank Loan Obligations - 10.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Asset-Backed Securities - 5.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Foreign Government and Government Agency Obligations - 4.0


&#160;

Fixed-Income Funds - 2.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

CMOs and Other Mortgage Related Securities - 2.0


&#160;

Preferred Securities - 1.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Common Stocks - 0.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Alternative Funds - 0.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Municipal Securities - 0.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Preferred Stocks - 0.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Short-Term Investments and Net Other Assets (Liabilities) - 2.6


&#160;






United States

83.8


United Kingdom

2.5


Canada

1.8


Mexico

1.4


Brazil

1.3


Dominican Republic

1.1


Germany

1.1


France

1.0


Israel

0.9


Others

5.1




GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

United States - 83.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

United Kingdom - 2.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Canada - 1.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Mexico - 1.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Brazil - 1.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Dominican Republic - 1.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Germany - 1.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

France - 1.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Israel - 0.9&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Others - 5.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;




&#160;




&#160;
&#160;
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    <oef:LargestHoldingsTableTextBlock contextRef="C000234192_ClassMember" id="ixv-19955">TOP HOLDINGS(% of Fund's net assets)

&#160;

&#160;


US Treasury Notes

27.1


&#160;


US Treasury Bonds

19.0


&#160;


Fidelity Real Estate High Income Fund

2.0


&#160;


Domino's Pizza Master Issuer LLC

1.9


&#160;


Petroleos Mexicanos

1.4


&#160;


Dominican Republic

1.1


&#160;


Brazilian Federative Republic

1.0


&#160;


Planet Fitness Master Issuer LLC

1.0


&#160;


Charter Communications Operating LLC / Charter Communications Operating Capital

0.9


&#160;


Millicom International Cellular SA

0.8


&#160;


&#160;

56.2

&#160;



</oef:LargestHoldingsTableTextBlock>
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    <oef:MaterialFundChngTextBlock contextRef="C000234192_ClassMember" id="ixv-20080">
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;How has the Fund changed?&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;This is a summary of certain changes to the Fund since September 1, 2025. For more complete information, you may review the Fund's next prospectus, which we expect to be available by October 30, 2026 at &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;fundresearch.fidelity.com/prospectus/sec&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt; or upon request at &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;1-877-208-0098&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:0px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt; or by sending an e-mail to &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;fidfunddocuments@fidelity.com&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;table cellpadding="0" cellspacing="0" style="border-collapse:collapse;border-style:none;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:50%; background-color:#ebf3e9;border-right:2px dashed #368627;padding:19px 19px 19px 19px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;The fund added a contractual management fee waiver during the reporting period. &lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:50%; background-color:#ebf3e9;padding:19px 19px 19px 19px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:MaterialFundChngTextBlock>
    <oef:SummaryOfChngLegendTextBlock contextRef="C000234192_ClassMember" id="ixv-20086">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;This is a summary of certain changes to the Fund since September 1, 2025. For more complete information, you may review the Fund's next prospectus, which we expect to be available by October 30, 2026 at &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;fundresearch.fidelity.com/prospectus/sec&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt; or upon request at &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;1-877-208-0098&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:0px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt; or by sending an e-mail to &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;fidfunddocuments@fidelity.com&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;.&lt;/span&gt;</oef:SummaryOfChngLegendTextBlock>
    <oef:UpdProspectusWebAddress contextRef="C000234192_ClassMember" id="ixv-20088">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;fundresearch.fidelity.com/prospectus/sec&lt;/span&gt;</oef:UpdProspectusWebAddress>
    <oef:UpdProspectusPhoneNumber contextRef="C000234192_ClassMember" id="ixv-20091">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;1-877-208-0098&lt;/span&gt;</oef:UpdProspectusPhoneNumber>
    <oef:UpdProspectusEmailAddress contextRef="C000234192_ClassMember" id="ixv-20095">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;fidfunddocuments@fidelity.com&lt;/span&gt;</oef:UpdProspectusEmailAddress>
    <oef:MaterialFundChngExpensesTextBlock contextRef="C000234192_ClassMember" id="ixv-20106">
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;The fund added a contractual management fee waiver during the reporting period. &lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:MaterialFundChngExpensesTextBlock>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-20164">2026-08-31</dei:DocumentPeriodEndDate>
    <oef:FundName contextRef="C000019121_ClassMember" id="ixv-20176">Fidelity&#xae; Investment Grade Bond Fund</oef:FundName>
    <oef:ClassName contextRef="C000019121_ClassMember" id="ixv-20179">Fidelity Advisor&#xae; Investment Grade Bond Fund Class A</oef:ClassName>
    <dei:TradingSymbol contextRef="C000019121_ClassMember" id="ixv-20183">FGBAX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000019121_ClassMember" id="ixv-20202">This annual shareholder report contains information about Fidelity&#xae; Investment Grade Bond Fund for the period September 1, 2025 to August 31, 2026.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000019121_ClassMember" id="ixv-20204">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000019121_ClassMember" id="ixv-20209">You can find additional information about the Fund at fundresearch.fidelity.com/prospectus/sec. You can also request this information by contacting us at 1-877-208-0098 or by sending an e-mail to fidfunddocuments@fidelity.com.</oef:AddlInfoTextBlock>
    <oef:AddlInfoWebsite contextRef="C000019121_ClassMember" id="ixv-20211">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000019121_ClassMember" id="ixv-20214">1-877-208-0098</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000019121_ClassMember" id="ixv-20217">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000019121_ClassMember" id="ixv-20224">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What were your Fund costs for the last year?&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(based on hypothetical $10,000 investment)&lt;/span&gt;&lt;/div&gt;
&lt;div&gt;&lt;span style="font-size:11px;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:bold;"&gt;FUND COST (PREVIOUS YEAR)&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;table cellpadding="0" cellspacing="0" style="border-collapse:collapse;border-style:none;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:51%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:21%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;Costs of a $10,000 investment&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:27%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;Costs paid as a percentage of a $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:51%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;Class A&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:21%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;76&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:27%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;0.75&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:ExpensesTextBlock>
    <oef:ExpensesPaidAmt
      contextRef="C000019121_ClassMember"
      decimals="0"
      id="ixv-355058"
      unitRef="usd">76</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000019121_ClassMember"
      decimals="INF"
      id="ixv-355059"
      unitRef="pure">0.0075</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000019121_ClassMember" id="ixv-20267">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What affected the Fund's performance this period?&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;U.S. taxable investment-grade bonds achieved a gain for the 12 months ending August 31, 2026, buoyed by three policy interest-rate cuts by the Federal Reserve in late 2025, but pulled down since then by rising bond yields amid higher consumer inflation, a resilient economy and heavy U.S. Treasury issuance.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Against this backdrop, the fund's top contributors relative to its benchmark, the Bloomberg U.S. Aggregate Bond Index, for the fiscal year came from overweight allocations to securitized products - specifically, outperforming stakes in asset-backed securities, including AAA-rated collateralized loan obligations, and commercial mortgage-backed securities.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Converserly, the fund's yield-curve positioning and its modestly longer-than-benchmark duration in a rising-rate environment modestly detracted.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;An underweight in agency mortgage-backed securities also modestly hindered performance.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;In terms of security selection, picks in corporate debt, sovereign government bonds and commercial mortgage-backed securities helped.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;The fund's managers did not make significant adjustments in positioning over the period and sought to keep the fund conservatively positioned versus the benchmark.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:FactorsAffectingPerfTextBlock>
    <oef:LineGraphTableTextBlock contextRef="C000019121_ClassMember" id="ixv-20291">How did the Fund perform over the past 10 years?

 &#160;&#160;
CUMULATIVE PERFORMANCE
August 31, 2016 through August 31, 2026. 
Initial investment of $10,000&#160;and the current sales charge was paid.
Class A


$9,600

$9,699


$9,578


$10,546


$11,422


$11,523


$10,151


$10,055


$10,809


$11,132


$11,285



Bloomberg U.S. Aggregate Bond Index


$10,000

$10,049


$9,944


$10,955


$11,665


$11,655


$10,313


$10,189


$10,933


$11,276


$11,489



&#160;

2016

2017

2018

2019

2020

2021

2022

2023

2024

2025

2026









&#160;
</oef:LineGraphTableTextBlock>
    <oef:LineGraphAndTableMeasureName contextRef="C000019121_LG_ClassMember_11YR" id="ixv-20312">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Class A&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000019121_ClassMember_AsOf_2016"
      decimals="0"
      id="ixv-355060"
      unitRef="usd">9600</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019121_ClassMember_AsOf_2017"
      decimals="0"
      id="ixv-355061"
      unitRef="usd">9699</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019121_ClassMember_AsOf_2018"
      decimals="0"
      id="ixv-355062"
      unitRef="usd">9578</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019121_ClassMember_AsOf_2019"
      decimals="0"
      id="ixv-355063"
      unitRef="usd">10546</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019121_ClassMember_AsOf_2020"
      decimals="0"
      id="ixv-355064"
      unitRef="usd">11422</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019121_ClassMember_AsOf_2021"
      decimals="0"
      id="ixv-355065"
      unitRef="usd">11523</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019121_ClassMember_AsOf_2022"
      decimals="0"
      id="ixv-355066"
      unitRef="usd">10151</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019121_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-355067"
      unitRef="usd">10055</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019121_ClassMember_AsOf_2024"
      decimals="0"
      id="ixv-355068"
      unitRef="usd">10809</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019121_ClassMember_AsOf_2025"
      decimals="0"
      id="ixv-355069"
      unitRef="usd">11132</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019121_ClassMember_AsOf_2026"
      decimals="0"
      id="ixv-355070"
      unitRef="usd">11285</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000019121_LG_1_AdditionalIndexMember_11YR"
      id="ixv-20361">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg U.S. Aggregate Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000019121_1_AdditionalIndexMember_AsOf_2016"
      decimals="0"
      id="ixv-355071"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019121_1_AdditionalIndexMember_AsOf_2017"
      decimals="0"
      id="ixv-355072"
      unitRef="usd">10049</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019121_1_AdditionalIndexMember_AsOf_2018"
      decimals="0"
      id="ixv-355073"
      unitRef="usd">9944</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019121_1_AdditionalIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-355074"
      unitRef="usd">10955</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019121_1_AdditionalIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-355075"
      unitRef="usd">11665</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019121_1_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-355076"
      unitRef="usd">11655</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019121_1_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-355077"
      unitRef="usd">10313</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019121_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-355078"
      unitRef="usd">10189</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019121_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-355079"
      unitRef="usd">10933</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019121_1_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-355080"
      unitRef="usd">11276</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019121_1_AdditionalIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-355081"
      unitRef="usd">11489</oef:AccmVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000019121_ClassMember" id="ixv-20462">AVERAGE ANNUAL TOTAL RETURNS:

&#160;

1 Year

5 Year

10 Year


Class A (incl. 4.00% sales charge) &#160;

-2.68%

-1.23%


1.22%


Class A (without 4.00% sales charge)

1.37%

-0.42%

1.63%


Bloomberg U.S. Aggregate Bond Index

1.89%


-0.29%


1.40%




&#160;
&#160;
Visit institutional.fidelity.com for more recent performance information.&#160;

&#160;


The Fund's past performance is not a good predictor of the Fund's future performance. &#160;The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.





</oef:AvgAnnlRtrTableTextBlock>
    <oef:AvgAnnlRtrPct
      contextRef="C000019121_ClassMember_1YR"
      decimals="INF"
      id="ixv-355082"
      unitRef="pure">-0.0268</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019121_ClassMember_5YR"
      decimals="INF"
      id="ixv-355083"
      unitRef="pure">-0.0123</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019121_ClassMember_10YR"
      decimals="INF"
      id="ixv-355084"
      unitRef="pure">0.0122</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019121_NoLoadClassMember_1YR"
      decimals="INF"
      id="ixv-355085"
      unitRef="pure">0.0137</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019121_NoLoadClassMember_5YR"
      decimals="INF"
      id="ixv-355086"
      unitRef="pure">-0.0042</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019121_NoLoadClassMember_10YR"
      decimals="INF"
      id="ixv-355087"
      unitRef="pure">0.0163</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019121_0_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-355088"
      unitRef="pure">0.0189</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019121_0_BBIndexMember_5YR"
      decimals="INF"
      id="ixv-355089"
      unitRef="pure">-0.0029</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019121_0_BBIndexMember_10YR"
      decimals="INF"
      id="ixv-355090"
      unitRef="pure">0.0140</oef:AvgAnnlRtrPct>
    <oef:UpdPerfInfoLocationTextBlock contextRef="C000019121_ClassMember" id="ixv-20536">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Visit &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;institutional.fidelity.com&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt; for more recent performance information.&lt;/span&gt;</oef:UpdPerfInfoLocationTextBlock>
    <oef:PerformancePastDoesNotIndicateFuture contextRef="C000019121_ClassMember" id="ixv-20548">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:italic;font-weight:normal;"&gt;The Fund's past performance is not a good predictor of the Fund's future performance.&lt;/span&gt;</oef:PerformancePastDoesNotIndicateFuture>
    <oef:NoDeductionOfTaxesTextBlock contextRef="C000019121_ClassMember" id="ixv-20552">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.&lt;/span&gt;</oef:NoDeductionOfTaxesTextBlock>
    <oef:AddlFundStatisticsTextBlock contextRef="C000019121_ClassMember" id="ixv-20558">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;Key Fund Statistics&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(as of August 31, 2026)&lt;/span&gt;&lt;/div&gt;
&lt;div&gt;&lt;span style="font-size:11px;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;table cellpadding="0" cellspacing="1" style="border-collapse:separate;border-style:none;margin:auto;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:63%; " valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:bold;"&gt;KEY FACTS&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt; &lt;span&gt;&#160;&lt;/span&gt;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fund Size&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;11,833,010,166&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;4,328&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;32,938,746&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="middle"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Portfolio Turnover&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;142&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:AddlFundStatisticsTextBlock>
    <us-gaap:AssetsNet
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      decimals="0"
      id="ixv-355091"
      unitRef="usd">11833010166</us-gaap:AssetsNet>
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      decimals="INF"
      id="ixv-355092"
      unitRef="holding">4328</oef:HoldingsCount>
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      decimals="0"
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    <us-gaap:InvestmentCompanyPortfolioTurnover
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      decimals="INF"
      id="ixv-355094"
      unitRef="pure">1.42</us-gaap:InvestmentCompanyPortfolioTurnover>
    <oef:HoldingsTableTextBlock contextRef="C000019121_ClassMember" id="ixv-20637">
&#160;
U.S. Government and U.S. Government Agency Obligations

61.0


AAA

5.5


AA

0.9


A

7.7


BBB

15.4


BB

2.9


B

0.8


CCC,CC,C

0.0


Not Rated

9.3




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

U.S. Government and U.S. Government Agency Obligations - 61.0


&#160;

AAA - 5.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

AA - 0.9&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

A - 7.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BBB - 15.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BB - 2.9&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

B - 0.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

CCC,CC,C - 0.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Not Rated - 9.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


Short-Term Investments and Net Other Assets (Liabilities) - (3.5)% 


&#160;


We have used ratings from Moody's Investors Service, Inc. Where Moody's&#xae; ratings are not available, we have used S&amp;P&#xae; ratings. All ratings are as of the date indicated and do not reflect subsequent changes.




&#160;
&#160;
&#160;
&#160;
U.S. Treasury Obligations

44.6


Corporate Bonds

24.3


U.S. Government Agency - Mortgage Securities

16.4


Asset-Backed Securities

9.2


CMOs and Other Mortgage Related Securities

8.7


Preferred Securities

0.2


Other Investments

0.1


Bank Loan Obligations

0.0


Options

0.0




ASSET ALLOCATION (% of Fund's net assets)


&#160;



&#160;

U.S. Treasury Obligations - 44.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Corporate Bonds - 24.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

U.S. Government Agency - Mortgage Securities - 16.4


&#160;

Asset-Backed Securities - 9.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

CMOs and Other Mortgage Related Securities - 8.7


&#160;

Preferred Securities - 0.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Other Investments - 0.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Bank Loan Obligations - 0.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Options - 0.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


Short-Term Investments and Net Other Assets (Liabilities) - (3.5)%


&#160;






United States

91.4


Grand Cayman (UK Overseas Ter)

4.4


Mexico

0.7


Bailiwick Of Jersey

0.7


Ireland

0.6


United Kingdom

0.5


Germany

0.3


Switzerland

0.3


Japan

0.2


Others

0.9




GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

United States - 91.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Grand Cayman (UK Overseas Ter) - 4.4&#160;&#160;&#160;&#160;


&#160;

Mexico - 0.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Bailiwick Of Jersey - 0.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Ireland - 0.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

United Kingdom - 0.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Germany - 0.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Switzerland - 0.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Japan - 0.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Others - 0.9&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;




&#160;




&#160;
&#160;
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    <oef:LargestHoldingsTableTextBlock contextRef="C000019121_ClassMember" id="ixv-21106">TOP HOLDINGS(% of Fund's net assets)

&#160;

&#160;


US Treasury Notes

34.3


&#160;


US Treasury Bonds

10.3


&#160;


Fannie Mae Mortgage pass-thru certificates

5.3


&#160;


Freddie Mac Gold Pool

4.4


&#160;


Ginnie Mae II Pool

3.8


&#160;


Uniform Mortgage Backed Securities

2.4


&#160;


Freddie Mac Multifamily Structured pass-thru certificates

2.2


&#160;


Citigroup Inc

1.2


&#160;


Bank of America Corp

1.1


&#160;


JPMorgan Chase &amp; Co

0.9


&#160;


&#160;

65.9

&#160;



</oef:LargestHoldingsTableTextBlock>
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      id="ixv-355123"
      unitRef="pure">0.343</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-355124"
      unitRef="pure">0.103</oef:PctOfNav>
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      unitRef="pure">0.053</oef:PctOfNav>
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    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-21277">2026-08-31</dei:DocumentPeriodEndDate>
    <oef:FundName contextRef="C000221556_ClassMember" id="ixv-21289">Fidelity&#xae; SAI Short-Term Bond Fund</oef:FundName>
    <oef:ClassName contextRef="C000221556_ClassMember" id="ixv-21292">Fidelity&#xae; SAI Short-Term Bond Fund</oef:ClassName>
    <dei:TradingSymbol contextRef="C000221556_ClassMember" id="ixv-21296">FZOMX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000221556_ClassMember" id="ixv-21315">This annual shareholder report contains information about Fidelity&#xae; SAI Short-Term Bond Fund for the period September 1, 2025 to August 31, 2026.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000221556_ClassMember" id="ixv-21317">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000221556_ClassMember" id="ixv-21322">You can find additional information about the Fund at fundresearch.fidelity.com/prospectus/sec. You can also request this information by contacting us at 1-800-544-3455 or by sending an e-mail to fidfunddocuments@fidelity.com.</oef:AddlInfoTextBlock>
    <oef:AddlInfoWebsite contextRef="C000221556_ClassMember" id="ixv-21324">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000221556_ClassMember" id="ixv-21327">1-800-544-3455</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000221556_ClassMember" id="ixv-21330">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000221556_ClassMember" id="ixv-21337">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What were your Fund costs for the last year?&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(based on hypothetical $10,000 investment)&lt;/span&gt;&lt;/div&gt;
&lt;div&gt;&lt;span style="font-size:11px;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:bold;"&gt;FUND COST (PREVIOUS YEAR)&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;table cellpadding="0" cellspacing="0" style="border-collapse:collapse;border-style:none;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:51%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:21%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;Costs of a $10,000 investment&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:27%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;Costs paid as a percentage of a $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:51%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity&#xae; SAI Short-Term Bond Fund&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:21%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;21&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:27%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;0.21&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:ExpensesTextBlock>
    <oef:ExpensesPaidAmt
      contextRef="C000221556_ClassMember"
      decimals="0"
      id="ixv-355133"
      unitRef="usd">21</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000221556_ClassMember"
      decimals="INF"
      id="ixv-355134"
      unitRef="pure">0.0021</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000221556_ClassMember" id="ixv-21380">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What affected the Fund's performance this period?&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;U.S. taxable investment-grade bonds achieved a gain for the 12 months ending August 31, 2026, buoyed by three policy interest-rate cuts by the Federal Reserve in late 2025, but pulled down since then by rising bond yields amid higher consumer inflation, a resilient economy and heavy U.S. Treasury issuance.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Against this backdrop, the fund's strategy of favoring short-term corporate bonds, while underweighting similar-duration U.S. Treasurys, contributed to its performance versus the benchmark Bloomberg U.S. 1-3 Year Government/Credit Bond Index for the fiscal year. Within corporates, debt holdings among financial institutions, especially banks, added notable value.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Non-benchmark exposure to asset-backed securities, including car loan debt and collateralized loan obligations, also meaningfully helped. A small, out-of-benchmark allocation to commercial mortgage-backed securities was beneficial as well.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;In contrast, the fund's yield-curve positioning detracted from relative performance.&#160;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;At period end, corporates made up about 42% of fund assets, up from roughly 38% a year ago and substantially overweight versus the benchmark average of 22%. Exposure to U.S. Treasurys stood at 40% as of August 31, down slightly from 41% a year ago, compared with an average of about 72% for the benchmark.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:FactorsAffectingPerfTextBlock>
    <oef:LineGraphTableTextBlock contextRef="C000221556_ClassMember" id="ixv-21401">How did the Fund perform over the life of Fund?

 &#160;&#160;
CUMULATIVE PERFORMANCE
September 15, 2020 through August 31, 2026. 
Initial investment of $10,000.
Fidelity&#xae; SAI Short-Term Bond Fund


$10,000

$10,054


$9,651


$9,863


$10,515


$11,039


$11,365



Bloomberg U.S. 1-3 Year Government/Credit Bond Index


$10,000

$10,039


$9,639


$9,791


$10,403


$10,885


$11,178



Bloomberg U.S. Aggregate Bond Index


$10,000

$9,977


$8,828


$8,723


$9,359


$9,653


$9,835



&#160;

2020

2021

2022

2023

2024

2025

2026









&#160;
</oef:LineGraphTableTextBlock>
    <oef:LineGraphAndTableMeasureName contextRef="C000221556_LG_ClassMember_7YR" id="ixv-21420">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity&#xae; SAI Short-Term Bond Fund&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000221556_ClassMember_AsOf_2020"
      decimals="0"
      id="ixv-355135"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000221556_ClassMember_AsOf_2021"
      decimals="0"
      id="ixv-355136"
      unitRef="usd">10054</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000221556_ClassMember_AsOf_2022"
      decimals="0"
      id="ixv-355137"
      unitRef="usd">9651</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000221556_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-355138"
      unitRef="usd">9863</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000221556_ClassMember_AsOf_2024"
      decimals="0"
      id="ixv-355139"
      unitRef="usd">10515</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000221556_ClassMember_AsOf_2025"
      decimals="0"
      id="ixv-355140"
      unitRef="usd">11039</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000221556_ClassMember_AsOf_2026"
      decimals="0"
      id="ixv-355141"
      unitRef="usd">11365</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000221556_LG_1_AdditionalIndexMember_7YR"
      id="ixv-21453">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg U.S. 1-3 Year Government/Credit Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000221556_1_AdditionalIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-355142"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000221556_1_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-355143"
      unitRef="usd">10039</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000221556_1_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-355144"
      unitRef="usd">9639</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000221556_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-355145"
      unitRef="usd">9791</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000221556_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-355146"
      unitRef="usd">10403</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000221556_1_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-355147"
      unitRef="usd">10885</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000221556_1_AdditionalIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-355148"
      unitRef="usd">11178</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000221556_LG_2_AdditionalIndexMember_7YR"
      id="ixv-21486">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg U.S. Aggregate Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000221556_2_AdditionalIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-355149"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000221556_2_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-355150"
      unitRef="usd">9977</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000221556_2_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-355151"
      unitRef="usd">8828</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000221556_2_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-355152"
      unitRef="usd">8723</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000221556_2_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-355153"
      unitRef="usd">9359</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000221556_2_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-355154"
      unitRef="usd">9653</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000221556_2_AdditionalIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-355155"
      unitRef="usd">9835</oef:AccmVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000221556_ClassMember" id="ixv-21559">AVERAGE ANNUAL TOTAL RETURNS:

&#160;

1 Year

5 Year

Life of Fund&#160;A


Fidelity&#xae; SAI Short-Term Bond Fund

2.95%

2.48%

2.17%


Bloomberg U.S. 1-3 Year Government/Credit Bond Index

2.69%


2.17%


1.89%


Bloomberg U.S. Aggregate Bond Index

1.89%


-0.29%


-0.28%




A&#160; &#160;From September 15, 2020

&#160;
Visit www.fidelity.com for more recent performance information.&#160;

&#160;


The Fund's past performance is not a good predictor of the Fund's future performance. &#160;The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.





</oef:AvgAnnlRtrTableTextBlock>
    <oef:AvgAnnlRtrPct
      contextRef="C000221556_NoLoadClassMember_1YR"
      decimals="INF"
      id="ixv-355156"
      unitRef="pure">0.0295</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000221556_NoLoadClassMember_5YR"
      decimals="INF"
      id="ixv-355157"
      unitRef="pure">0.0248</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000221556_NoLoadClassMember_2025-09-01_2026-08-31"
      decimals="INF"
      id="ixv-355158"
      unitRef="pure">0.0217</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000221556_0_AdditionalIndexMember_1YR"
      decimals="INF"
      id="ixv-355159"
      unitRef="pure">0.0269</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000221556_0_AdditionalIndexMember_5YR"
      decimals="INF"
      id="ixv-355160"
      unitRef="pure">0.0217</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000221556_0_AdditionalIndexMember_LOC"
      decimals="INF"
      id="ixv-355161"
      unitRef="pure">0.0189</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000221556_1_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-355162"
      unitRef="pure">0.0189</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000221556_1_BBIndexMember_5YR"
      decimals="INF"
      id="ixv-355163"
      unitRef="pure">-0.0029</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000221556_1_BBIndexMember_LOC"
      decimals="INF"
      id="ixv-355164"
      unitRef="pure">-0.0028</oef:AvgAnnlRtrPct>
    <oef:PerfInceptionDate
      contextRef="C000221556_Perf_2020-09-15_ClassMember"
      id="ixv-21630">2020-09-15</oef:PerfInceptionDate>
    <oef:UpdPerfInfoLocationTextBlock contextRef="C000221556_ClassMember" id="ixv-21640">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Visit &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;www.fidelity.com&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt; for more recent performance information.&lt;/span&gt;</oef:UpdPerfInfoLocationTextBlock>
    <oef:PerformancePastDoesNotIndicateFuture contextRef="C000221556_ClassMember" id="ixv-21652">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:italic;font-weight:normal;"&gt;The Fund's past performance is not a good predictor of the Fund's future performance.&lt;/span&gt;</oef:PerformancePastDoesNotIndicateFuture>
    <oef:NoDeductionOfTaxesTextBlock contextRef="C000221556_ClassMember" id="ixv-21656">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.&lt;/span&gt;</oef:NoDeductionOfTaxesTextBlock>
    <oef:AddlFundStatisticsTextBlock contextRef="C000221556_ClassMember" id="ixv-21662">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;Key Fund Statistics&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(as of August 31, 2026)&lt;/span&gt;&lt;/div&gt;
&lt;div&gt;&lt;span style="font-size:11px;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;table cellpadding="0" cellspacing="1" style="border-collapse:separate;border-style:none;margin:auto;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:63%; " valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:bold;"&gt;KEY FACTS&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt; &lt;span&gt;&#160;&lt;/span&gt;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fund Size&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;709,338,777&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;426&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;5,002,383&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="middle"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Portfolio Turnover&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;117&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:AddlFundStatisticsTextBlock>
    <us-gaap:AssetsNet
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      decimals="0"
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    <oef:HoldingsCount
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      unitRef="holding">426</oef:HoldingsCount>
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      decimals="0"
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      unitRef="usd">5002383</oef:AdvisoryFeesPaidAmt>
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    <oef:HoldingsTableTextBlock contextRef="C000221556_ClassMember" id="ixv-21737">
&#160;
U.S. Government and U.S. Government Agency Obligations

40.7


AAA

10.4


AA

1.4


A

20.1


BBB

19.4


BB

1.4


Not Rated

6.1


Short-Term Investments and Net Other Assets (Liabilities)

0.5




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

U.S. Government and U.S. Government Agency Obligations - 40.7


&#160;

AAA - 10.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

AA - 1.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

A - 20.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BBB - 19.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BB - 1.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Not Rated - 6.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Short-Term Investments and Net Other Assets (Liabilities) - 0.5


&#160;


We have used ratings from Moody's Investors Service, Inc. Where Moody's&#xae; ratings are not available, we have used S&amp;P&#xae; ratings. All ratings are as of the date indicated and do not reflect subsequent changes.




&#160;
&#160;
&#160;
&#160;
Corporate Bonds

41.2


U.S. Treasury Obligations

40.7


Asset-Backed Securities

12.7


CMOs and Other Mortgage Related Securities

4.4


Other Investments

0.5


U.S. Government Agency - Mortgage Securities

0.0


Short-Term Investments and Net Other Assets (Liabilities)

0.5




ASSET ALLOCATION (% of Fund's net assets)


&#160;



&#160;

Corporate Bonds - 41.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

U.S. Treasury Obligations - 40.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Asset-Backed Securities - 12.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

CMOs and Other Mortgage Related Securities - 4.4


&#160;

Other Investments - 0.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

U.S. Government Agency - Mortgage Securities - 0.0


&#160;

Short-Term Investments and Net Other Assets (Liabilities) - 0.5


&#160;






United States

79.4


Grand Cayman (UK Overseas Ter)

4.1


United Kingdom

3.7


Germany

2.8


Canada

2.6


France

1.6


Ireland

1.3


Bailiwick Of Jersey

1.2


Japan

1.1


Others

2.2




GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

United States - 79.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Grand Cayman (UK Overseas Ter) - 4.1&#160;&#160;&#160;&#160;


&#160;

United Kingdom - 3.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Germany - 2.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Canada - 2.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

France - 1.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Ireland - 1.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Bailiwick Of Jersey - 1.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Japan - 1.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Others - 2.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;




&#160;




&#160;
&#160;
</oef:HoldingsTableTextBlock>
    <oef:PctOfNav
      contextRef="C000221556_QD_USGovernmentandUSGovernmentAgencyObligations_Member"
      decimals="INF"
      id="ixv-355169"
      unitRef="pure">0.407</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000221556_QD_AAA_Member"
      decimals="INF"
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      unitRef="pure">0.104</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-355171"
      unitRef="pure">0.014</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000221556_QD_A_Member"
      decimals="INF"
      id="ixv-355172"
      unitRef="pure">0.201</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000221556_QD_BBB_Member"
      decimals="INF"
      id="ixv-355173"
      unitRef="pure">0.194</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000221556_QD_BB_Member"
      decimals="INF"
      id="ixv-355174"
      unitRef="pure">0.014</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000221556_QD_NotRated_Member"
      decimals="INF"
      id="ixv-355175"
      unitRef="pure">0.061</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000221556_QD_ShortTermInvestmentsandNetOtherAssetsLiabilities_Member"
      decimals="INF"
      id="ixv-355176"
      unitRef="pure">0.005</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000221556_AA_CorporateBonds_Member"
      decimals="INF"
      id="ixv-355177"
      unitRef="pure">0.412</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000221556_AA_USTreasuryObligations_Member"
      decimals="INF"
      id="ixv-355178"
      unitRef="pure">0.407</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000221556_AA_AssetBackedSecurities_Member"
      decimals="INF"
      id="ixv-355179"
      unitRef="pure">0.127</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000221556_AA_CMOsandOtherMortgageRelatedSecurities_Member"
      decimals="INF"
      id="ixv-355180"
      unitRef="pure">0.044</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000221556_AA_OtherInvestments_Member"
      decimals="INF"
      id="ixv-355181"
      unitRef="pure">0.005</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000221556_AA_USGovernmentAgencyMortgageSecurities_Member"
      decimals="INF"
      id="ixv-355182"
      unitRef="pure">0.000</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000221556_AA_ShortTermInvestmentsandNetOtherAssetsLiabilities_Member"
      decimals="INF"
      id="ixv-355183"
      unitRef="pure">0.005</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000221556_GD_US_Member"
      decimals="INF"
      id="ixv-355184"
      unitRef="pure">0.794</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000221556_GD_GrandCaymanUKOverseasTer_Member"
      decimals="INF"
      id="ixv-355185"
      unitRef="pure">0.041</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000221556_GD_GB_Member"
      decimals="INF"
      id="ixv-355186"
      unitRef="pure">0.037</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000221556_GD_DE_Member"
      decimals="INF"
      id="ixv-355187"
      unitRef="pure">0.028</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000221556_GD_CA_Member"
      decimals="INF"
      id="ixv-355188"
      unitRef="pure">0.026</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000221556_GD_FR_Member"
      decimals="INF"
      id="ixv-355189"
      unitRef="pure">0.016</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000221556_GD_IE_Member"
      decimals="INF"
      id="ixv-355190"
      unitRef="pure">0.013</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000221556_GD_BailiwickOfJersey_Member"
      decimals="INF"
      id="ixv-355191"
      unitRef="pure">0.012</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000221556_GD_JP_Member"
      decimals="INF"
      id="ixv-355192"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000221556_GD_Other_Member"
      decimals="INF"
      id="ixv-355193"
      unitRef="pure">0.022</oef:PctOfNav>
    <oef:LargestHoldingsTableTextBlock contextRef="C000221556_ClassMember" id="ixv-22159">TOP HOLDINGS(% of Fund's net assets)

&#160;

&#160;


US Treasury Notes

40.7


&#160;


Wells Fargo &amp; Co

1.2


&#160;


Citigroup Inc

1.2


&#160;


JPMorgan Chase &amp; Co

1.1


&#160;


Bank of America Corp

1.1


&#160;


General Motors Financial Co Inc

1.1


&#160;


Goldman Sachs Group Inc/The

1.0


&#160;


Hyundai Capital America

0.9


&#160;


Deutsche Bank AG/New York NY

0.9


&#160;


Societe Generale SA

0.9


&#160;


&#160;

50.1

&#160;



</oef:LargestHoldingsTableTextBlock>
    <oef:PctOfNav
      contextRef="C000221556_TH_0_Member"
      decimals="INF"
      id="ixv-355194"
      unitRef="pure">0.407</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000221556_TH_1_Member"
      decimals="INF"
      id="ixv-355195"
      unitRef="pure">0.012</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000221556_TH_2_Member"
      decimals="INF"
      id="ixv-355196"
      unitRef="pure">0.012</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000221556_TH_3_Member"
      decimals="INF"
      id="ixv-355197"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000221556_TH_4_Member"
      decimals="INF"
      id="ixv-355198"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000221556_TH_5_Member"
      decimals="INF"
      id="ixv-355199"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000221556_TH_6_Member"
      decimals="INF"
      id="ixv-355200"
      unitRef="pure">0.010</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000221556_TH_7_Member"
      decimals="INF"
      id="ixv-355201"
      unitRef="pure">0.009</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000221556_TH_8_Member"
      decimals="INF"
      id="ixv-355202"
      unitRef="pure">0.009</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000221556_TH_9_Member"
      decimals="INF"
      id="ixv-355203"
      unitRef="pure">0.009</oef:PctOfNav>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-22330">2026-08-31</dei:DocumentPeriodEndDate>
    <oef:MaterialFundChngNoticeTextBlock contextRef="C000234189_ClassMember" id="ixv-22334">This report describes changes to the Fund that occurred during the reporting period.</oef:MaterialFundChngNoticeTextBlock>
    <oef:FundName contextRef="C000234189_ClassMember" id="ixv-22345">Fidelity&#xae; Tactical Bond Fund</oef:FundName>
    <oef:ClassName contextRef="C000234189_ClassMember" id="ixv-22348">Fidelity&#xae; Tactical Bond Fund</oef:ClassName>
    <dei:TradingSymbol contextRef="C000234189_ClassMember" id="ixv-22352">FBAGX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000234189_ClassMember" id="ixv-22371">This annual shareholder report contains information about Fidelity&#xae; Tactical Bond Fund for the period September 1, 2025 to August 31, 2026.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000234189_ClassMember" id="ixv-22373">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000234189_ClassMember" id="ixv-22378">You can find additional information about the Fund at fundresearch.fidelity.com/prospectus/sec. You can also request this information by contacting us at 1-800-544-8544 or by sending an e-mail to fidfunddocuments@fidelity.com.</oef:AddlInfoTextBlock>
    <oef:AddlInfoWebsite contextRef="C000234189_ClassMember" id="ixv-22380">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000234189_ClassMember" id="ixv-22383">1-800-544-8544</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000234189_ClassMember" id="ixv-22386">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000234189_ClassMember" id="ixv-22393">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What were your Fund costs for the last year?&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(based on hypothetical $10,000 investment)&lt;/span&gt;&lt;/div&gt;
&lt;div&gt;&lt;span style="font-size:11px;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:bold;"&gt;FUND COST (PREVIOUS YEAR)&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;table cellpadding="0" cellspacing="0" style="border-collapse:collapse;border-style:none;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:51%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:21%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;Costs of a $10,000 investment&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:27%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;Costs paid as a percentage of a $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:51%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity&#xae; Tactical Bond Fund&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:21%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;71&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:27%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;0.70&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:ExpensesTextBlock>
    <oef:ExpensesPaidAmt
      contextRef="C000234189_ClassMember"
      decimals="0"
      id="ixv-355204"
      unitRef="usd">71</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000234189_ClassMember"
      decimals="INF"
      id="ixv-355205"
      unitRef="pure">0.0070</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000234189_ClassMember" id="ixv-22436">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What affected the Fund's performance this period?&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;U.S. taxable investment-grade bonds achieved a gain for the 12 months ending August 31, 2026, buoyed by three policy interest-rate cuts by the Federal Reserve in late 2025, but pulled down since then by rising bond yields amid higher consumer inflation, a resilient economy and heavy U.S. Treasury issuance.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Against this backdrop, the fund's top contributors relative to its benchmark, the Bloomberg U.S. Aggregate Bond Index, for the fiscal year came from out-of-benchmark allocations to outperforming high-yield bonds, global bonds and emerging-markets debt.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Converserly, the ETF's yield-curve positioning and its longer-than-benchmark duration in a rising-rate environment detracted from performance versus the benchmark.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;An underweight in agency mortgage-backed securities also modestly hurt.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Notable changes in positioning include increased exposure to U.S. Treasurys and reduced exposure to high-yield bonds.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:FactorsAffectingPerfTextBlock>
    <oef:LineGraphTableTextBlock contextRef="C000234189_ClassMember" id="ixv-22457">How did the Fund perform over the life of Fund?

 &#160;&#160;
CUMULATIVE PERFORMANCE
February 10, 2022 through August 31, 2026. 
Initial investment of $10,000.
Fidelity&#xae; Tactical Bond Fund


$10,000

$9,270


$9,317


$10,049


$10,392



Bloomberg U.S. Aggregate Bond Index


$10,000

$9,301


$9,190


$9,861


$10,170



&#160;

2022

2023

2024

2025

2026









&#160;
</oef:LineGraphTableTextBlock>
    <oef:LineGraphAndTableMeasureName contextRef="C000234189_LG_ClassMember_5YR" id="ixv-22476">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity&#xae; Tactical Bond Fund&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000234189_ClassMember_AsOf_2022"
      decimals="0"
      id="ixv-355206"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000234189_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-355207"
      unitRef="usd">9270</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000234189_ClassMember_AsOf_2024"
      decimals="0"
      id="ixv-355208"
      unitRef="usd">9317</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000234189_ClassMember_AsOf_2025"
      decimals="0"
      id="ixv-355209"
      unitRef="usd">10049</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000234189_ClassMember_AsOf_2026"
      decimals="0"
      id="ixv-355210"
      unitRef="usd">10392</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000234189_LG_1_AdditionalIndexMember_5YR"
      id="ixv-22501">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg U.S. Aggregate Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000234189_1_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-355211"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000234189_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-355212"
      unitRef="usd">9301</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000234189_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-355213"
      unitRef="usd">9190</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000234189_1_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-355214"
      unitRef="usd">9861</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000234189_1_AdditionalIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-355215"
      unitRef="usd">10170</oef:AccmVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000234189_ClassMember" id="ixv-22560">AVERAGE ANNUAL TOTAL RETURNS:

&#160;

1 Year

Life of Fund&#160;A


Fidelity&#xae; Tactical Bond Fund

2.51%

1.40%


Bloomberg U.S. Aggregate Bond Index

1.89%


0.78%




A&#160; &#160;From February 10, 2022

&#160;
Visit www.fidelity.com for more recent performance information.&#160;

&#160;


The Fund's past performance is not a good predictor of the Fund's future performance. &#160;The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.





</oef:AvgAnnlRtrTableTextBlock>
    <oef:AvgAnnlRtrPct
      contextRef="C000234189_NoLoadClassMember_1YR"
      decimals="INF"
      id="ixv-355216"
      unitRef="pure">0.0251</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000234189_NoLoadClassMember_2025-09-01_2026-08-31"
      decimals="INF"
      id="ixv-355217"
      unitRef="pure">0.0140</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000234189_0_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-355218"
      unitRef="pure">0.0189</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000234189_0_BBIndexMember_LOC"
      decimals="INF"
      id="ixv-355219"
      unitRef="pure">0.0078</oef:AvgAnnlRtrPct>
    <oef:PerfInceptionDate
      contextRef="C000234189_Perf_2022-02-10_ClassMember"
      id="ixv-22604">2022-02-10</oef:PerfInceptionDate>
    <oef:UpdPerfInfoLocationTextBlock contextRef="C000234189_ClassMember" id="ixv-22614">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Visit &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;www.fidelity.com&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt; for more recent performance information.&lt;/span&gt;</oef:UpdPerfInfoLocationTextBlock>
    <oef:PerformancePastDoesNotIndicateFuture contextRef="C000234189_ClassMember" id="ixv-22626">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:italic;font-weight:normal;"&gt;The Fund's past performance is not a good predictor of the Fund's future performance.&lt;/span&gt;</oef:PerformancePastDoesNotIndicateFuture>
    <oef:NoDeductionOfTaxesTextBlock contextRef="C000234189_ClassMember" id="ixv-22630">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.&lt;/span&gt;</oef:NoDeductionOfTaxesTextBlock>
    <oef:AddlFundStatisticsTextBlock contextRef="C000234189_ClassMember" id="ixv-22636">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;Key Fund Statistics&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(as of August 31, 2026)&lt;/span&gt;&lt;/div&gt;
&lt;div&gt;&lt;span style="font-size:11px;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;table cellpadding="0" cellspacing="1" style="border-collapse:separate;border-style:none;margin:auto;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:63%; " valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:bold;"&gt;KEY FACTS&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt; &lt;span&gt;&#160;&lt;/span&gt;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fund Size&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;43,942,866&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;99&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;284,923&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="middle"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Portfolio Turnover&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;28&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:AddlFundStatisticsTextBlock>
    <us-gaap:AssetsNet
      contextRef="C000234189_InstantMember"
      decimals="0"
      id="ixv-355220"
      unitRef="usd">43942866</us-gaap:AssetsNet>
    <oef:HoldingsCount
      contextRef="C000234189_InstantMember"
      decimals="INF"
      id="ixv-355221"
      unitRef="holding">99</oef:HoldingsCount>
    <oef:AdvisoryFeesPaidAmt
      contextRef="C000234189_ClassMember"
      decimals="0"
      id="ixv-355222"
      unitRef="usd">284923</oef:AdvisoryFeesPaidAmt>
    <us-gaap:InvestmentCompanyPortfolioTurnover
      contextRef="C000234189_ClassMember"
      decimals="INF"
      id="ixv-355223"
      unitRef="pure">0.28</us-gaap:InvestmentCompanyPortfolioTurnover>
    <oef:HoldingsTableTextBlock contextRef="C000234189_ClassMember" id="ixv-22715">
&#160;
U.S. Government and U.S. Government Agency Obligations

46.1


AAA

1.2


AA

0.2


A

3.4


BBB

12.0


BB

12.3


B

11.9


CCC,CC,C

2.6


Not Rated

5.0


Equities

2.7


Short-Term Investments and Net Other Assets (Liabilities)

2.6




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

U.S. Government and U.S. Government Agency Obligations - 46.1


&#160;

AAA - 1.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

AA - 0.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

A - 3.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BBB - 12.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BB - 12.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

B - 11.9&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

CCC,CC,C - 2.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Not Rated - 5.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Equities - 2.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Short-Term Investments and Net Other Assets (Liabilities) - 2.6


&#160;


We have used ratings from Moody's Investors Service, Inc. Where Moody's&#xae; ratings are not available, we have used S&amp;P&#xae; ratings. All ratings are as of the date indicated and do not reflect subsequent changes.




&#160;
&#160;
&#160;
&#160;
U.S. Treasury Obligations

46.1


Corporate Bonds

24.6


Bank Loan Obligations

10.5


Asset-Backed Securities

5.4


Foreign Government and Government Agency Obligations

4.0


Fixed-Income Funds

2.0


CMOs and Other Mortgage Related Securities

2.0


Preferred Securities

1.5


Common Stocks

0.5


Alternative Funds

0.4


Municipal Securities

0.2


Preferred Stocks

0.2


Short-Term Investments and Net Other Assets (Liabilities)

2.6




ASSET ALLOCATION (% of Fund's net assets)


&#160;



&#160;

U.S. Treasury Obligations - 46.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Corporate Bonds - 24.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Bank Loan Obligations - 10.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Asset-Backed Securities - 5.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Foreign Government and Government Agency Obligations - 4.0


&#160;

Fixed-Income Funds - 2.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

CMOs and Other Mortgage Related Securities - 2.0


&#160;

Preferred Securities - 1.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Common Stocks - 0.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Alternative Funds - 0.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Municipal Securities - 0.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Preferred Stocks - 0.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Short-Term Investments and Net Other Assets (Liabilities) - 2.6


&#160;






United States

83.8


United Kingdom

2.5


Canada

1.8


Mexico

1.4


Brazil

1.3


Dominican Republic

1.1


Germany

1.1


France

1.0


Israel

0.9


Others

5.1




GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

United States - 83.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

United Kingdom - 2.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Canada - 1.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Mexico - 1.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Brazil - 1.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Dominican Republic - 1.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Germany - 1.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

France - 1.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Israel - 0.9&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Others - 5.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;




&#160;




&#160;
&#160;
</oef:HoldingsTableTextBlock>
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      unitRef="pure">0.005</oef:PctOfNav>
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      decimals="INF"
      id="ixv-355244"
      unitRef="pure">0.004</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-355245"
      unitRef="pure">0.002</oef:PctOfNav>
    <oef:PctOfNav
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      id="ixv-355246"
      unitRef="pure">0.002</oef:PctOfNav>
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      unitRef="pure">0.026</oef:PctOfNav>
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      unitRef="pure">0.838</oef:PctOfNav>
    <oef:PctOfNav
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      unitRef="pure">0.018</oef:PctOfNav>
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      decimals="INF"
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      unitRef="pure">0.014</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
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      unitRef="pure">0.013</oef:PctOfNav>
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      decimals="INF"
      id="ixv-355253"
      unitRef="pure">0.011</oef:PctOfNav>
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      decimals="INF"
      id="ixv-355254"
      unitRef="pure">0.011</oef:PctOfNav>
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      contextRef="C000234189_GD_FR_Member"
      decimals="INF"
      id="ixv-355255"
      unitRef="pure">0.010</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-355256"
      unitRef="pure">0.009</oef:PctOfNav>
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      unitRef="pure">0.051</oef:PctOfNav>
    <oef:LargestHoldingsTableTextBlock contextRef="C000234189_ClassMember" id="ixv-23254">TOP HOLDINGS(% of Fund's net assets)

&#160;

&#160;


US Treasury Notes

27.1


&#160;


US Treasury Bonds

19.0


&#160;


Fidelity Real Estate High Income Fund

2.0


&#160;


Domino's Pizza Master Issuer LLC

1.9


&#160;


Petroleos Mexicanos

1.4


&#160;


Dominican Republic

1.1


&#160;


Brazilian Federative Republic

1.0


&#160;


Planet Fitness Master Issuer LLC

1.0


&#160;


Charter Communications Operating LLC / Charter Communications Operating Capital

0.9


&#160;


Millicom International Cellular SA

0.8


&#160;


&#160;

56.2

&#160;



</oef:LargestHoldingsTableTextBlock>
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      id="ixv-355258"
      unitRef="pure">0.271</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000234189_TH_1_Member"
      decimals="INF"
      id="ixv-355259"
      unitRef="pure">0.190</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-355260"
      unitRef="pure">0.020</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000234189_TH_3_Member"
      decimals="INF"
      id="ixv-355261"
      unitRef="pure">0.019</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000234189_TH_4_Member"
      decimals="INF"
      id="ixv-355262"
      unitRef="pure">0.014</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000234189_TH_5_Member"
      decimals="INF"
      id="ixv-355263"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-355264"
      unitRef="pure">0.010</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000234189_TH_7_Member"
      decimals="INF"
      id="ixv-355265"
      unitRef="pure">0.010</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-355266"
      unitRef="pure">0.009</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000234189_TH_9_Member"
      decimals="INF"
      id="ixv-355267"
      unitRef="pure">0.008</oef:PctOfNav>
    <oef:MaterialFundChngTextBlock contextRef="C000234189_ClassMember" id="ixv-23379">
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;How has the Fund changed?&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;This is a summary of certain changes to the Fund since September 1, 2025. For more complete information, you may review the Fund's next prospectus, which we expect to be available by October 30, 2026 at &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;fundresearch.fidelity.com/prospectus/sec&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt; or upon request at &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;1-800-544-8544&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:0px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt; or by sending an e-mail to &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;fidfunddocuments@fidelity.com&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;table cellpadding="0" cellspacing="0" style="border-collapse:collapse;border-style:none;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:50%; background-color:#ebf3e9;border-right:2px dashed #368627;padding:19px 19px 19px 19px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;The fund added a contractual management fee waiver during the reporting period. &lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:50%; background-color:#ebf3e9;padding:19px 19px 19px 19px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:MaterialFundChngTextBlock>
    <oef:SummaryOfChngLegendTextBlock contextRef="C000234189_ClassMember" id="ixv-23385">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;This is a summary of certain changes to the Fund since September 1, 2025. For more complete information, you may review the Fund's next prospectus, which we expect to be available by October 30, 2026 at &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;fundresearch.fidelity.com/prospectus/sec&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt; or upon request at &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;1-800-544-8544&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:0px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt; or by sending an e-mail to &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;fidfunddocuments@fidelity.com&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;.&lt;/span&gt;</oef:SummaryOfChngLegendTextBlock>
    <oef:UpdProspectusWebAddress contextRef="C000234189_ClassMember" id="ixv-23387">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;fundresearch.fidelity.com/prospectus/sec&lt;/span&gt;</oef:UpdProspectusWebAddress>
    <oef:UpdProspectusPhoneNumber contextRef="C000234189_ClassMember" id="ixv-23390">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;1-800-544-8544&lt;/span&gt;</oef:UpdProspectusPhoneNumber>
    <oef:UpdProspectusEmailAddress contextRef="C000234189_ClassMember" id="ixv-23394">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;fidfunddocuments@fidelity.com&lt;/span&gt;</oef:UpdProspectusEmailAddress>
    <oef:MaterialFundChngExpensesTextBlock contextRef="C000234189_ClassMember" id="ixv-23405">
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;The fund added a contractual management fee waiver during the reporting period. &lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:MaterialFundChngExpensesTextBlock>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-23463">2026-08-31</dei:DocumentPeriodEndDate>
    <oef:FundName contextRef="C000205019_ClassMember" id="ixv-23475">Fidelity&#xae; Investment Grade Bond Fund</oef:FundName>
    <oef:ClassName contextRef="C000205019_ClassMember" id="ixv-23478">Fidelity Advisor&#xae; Investment Grade Bond Fund Class Z</oef:ClassName>
    <dei:TradingSymbol contextRef="C000205019_ClassMember" id="ixv-23482">FIKQX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000205019_ClassMember" id="ixv-23501">This annual shareholder report contains information about Fidelity&#xae; Investment Grade Bond Fund for the period September 1, 2025 to August 31, 2026.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000205019_ClassMember" id="ixv-23503">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000205019_ClassMember" id="ixv-23508">You can find additional information about the Fund at fundresearch.fidelity.com/prospectus/sec. You can also request this information by contacting us at 1-877-208-0098 or by sending an e-mail to fidfunddocuments@fidelity.com.</oef:AddlInfoTextBlock>
    <oef:AddlInfoWebsite contextRef="C000205019_ClassMember" id="ixv-23510">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000205019_ClassMember" id="ixv-23513">1-877-208-0098</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000205019_ClassMember" id="ixv-23516">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000205019_ClassMember" id="ixv-23523">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What were your Fund costs for the last year?&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(based on hypothetical $10,000 investment)&lt;/span&gt;&lt;/div&gt;
&lt;div&gt;&lt;span style="font-size:11px;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:bold;"&gt;FUND COST (PREVIOUS YEAR)&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;table cellpadding="0" cellspacing="0" style="border-collapse:collapse;border-style:none;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:51%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:21%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;Costs of a $10,000 investment&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:27%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;Costs paid as a percentage of a $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:51%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;Class Z&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:21%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;36&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:27%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;0.36&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:ExpensesTextBlock>
    <oef:ExpensesPaidAmt
      contextRef="C000205019_ClassMember"
      decimals="0"
      id="ixv-355268"
      unitRef="usd">36</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000205019_ClassMember"
      decimals="INF"
      id="ixv-355269"
      unitRef="pure">0.0036</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000205019_ClassMember" id="ixv-23566">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What affected the Fund's performance this period?&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;U.S. taxable investment-grade bonds achieved a gain for the 12 months ending August 31, 2026, buoyed by three policy interest-rate cuts by the Federal Reserve in late 2025, but pulled down since then by rising bond yields amid higher consumer inflation, a resilient economy and heavy U.S. Treasury issuance.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Against this backdrop, the fund's top contributors relative to its benchmark, the Bloomberg U.S. Aggregate Bond Index, for the fiscal year came from overweight allocations to securitized products - specifically, outperforming stakes in asset-backed securities, including AAA-rated collateralized loan obligations, and commercial mortgage-backed securities.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Converserly, the fund's yield-curve positioning and its modestly longer-than-benchmark duration in a rising-rate environment modestly detracted.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;An underweight in agency mortgage-backed securities also modestly hindered performance.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;In terms of security selection, picks in corporate debt, sovereign government bonds and commercial mortgage-backed securities helped.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;The fund's managers did not make significant adjustments in positioning over the period and sought to keep the fund conservatively positioned versus the benchmark.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:FactorsAffectingPerfTextBlock>
    <oef:LineGraphTableTextBlock contextRef="C000205019_ClassMember" id="ixv-23590">How did the Fund perform over the life of Fund?

 &#160;&#160;
CUMULATIVE PERFORMANCE
October 2, 2018 through August 31, 2026. 
Initial investment of $10,000.
Class Z


$10,000

$11,097


$12,064


$12,218


$10,809


$10,750


$11,601


$11,994


$12,190



Bloomberg U.S. Aggregate Bond Index


$10,000

$11,086


$11,804


$11,794


$10,436


$10,311


$11,064


$11,411


$11,626



&#160;

2018

2019

2020

2021

2022

2023

2024

2025

2026









&#160;
</oef:LineGraphTableTextBlock>
    <oef:LineGraphAndTableMeasureName contextRef="C000205019_LG_ClassMember_9YR" id="ixv-23609">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Class Z&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000205019_ClassMember_AsOf_2018"
      decimals="0"
      id="ixv-355270"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000205019_ClassMember_AsOf_2019"
      decimals="0"
      id="ixv-355271"
      unitRef="usd">11097</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000205019_ClassMember_AsOf_2020"
      decimals="0"
      id="ixv-355272"
      unitRef="usd">12064</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000205019_ClassMember_AsOf_2021"
      decimals="0"
      id="ixv-355273"
      unitRef="usd">12218</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000205019_ClassMember_AsOf_2022"
      decimals="0"
      id="ixv-355274"
      unitRef="usd">10809</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000205019_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-355275"
      unitRef="usd">10750</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000205019_ClassMember_AsOf_2024"
      decimals="0"
      id="ixv-355276"
      unitRef="usd">11601</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000205019_ClassMember_AsOf_2025"
      decimals="0"
      id="ixv-355277"
      unitRef="usd">11994</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000205019_ClassMember_AsOf_2026"
      decimals="0"
      id="ixv-355278"
      unitRef="usd">12190</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000205019_LG_1_AdditionalIndexMember_9YR"
      id="ixv-23650">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg U.S. Aggregate Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000205019_1_AdditionalIndexMember_AsOf_2018"
      decimals="0"
      id="ixv-355279"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000205019_1_AdditionalIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-355280"
      unitRef="usd">11086</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000205019_1_AdditionalIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-355281"
      unitRef="usd">11804</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000205019_1_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-355282"
      unitRef="usd">11794</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000205019_1_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-355283"
      unitRef="usd">10436</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000205019_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-355284"
      unitRef="usd">10311</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000205019_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-355285"
      unitRef="usd">11064</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000205019_1_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-355286"
      unitRef="usd">11411</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000205019_1_AdditionalIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-355287"
      unitRef="usd">11626</oef:AccmVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000205019_ClassMember" id="ixv-23737">AVERAGE ANNUAL TOTAL RETURNS:

&#160;

1 Year

5 Year

Life of Fund&#160;A


Class Z

1.63%

-0.05%

2.53%


Bloomberg U.S. Aggregate Bond Index

1.89%


-0.29%


1.92%




A&#160; &#160;From October 2, 2018

&#160;
Visit institutional.fidelity.com for more recent performance information.&#160;

&#160;


The Fund's past performance is not a good predictor of the Fund's future performance. &#160;The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.





</oef:AvgAnnlRtrTableTextBlock>
    <oef:AvgAnnlRtrPct
      contextRef="C000205019_NoLoadClassMember_1YR"
      decimals="INF"
      id="ixv-355288"
      unitRef="pure">0.0163</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000205019_NoLoadClassMember_5YR"
      decimals="INF"
      id="ixv-355289"
      unitRef="pure">-0.0005</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000205019_NoLoadClassMember_2025-09-01_2026-08-31"
      decimals="INF"
      id="ixv-355290"
      unitRef="pure">0.0253</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000205019_0_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-355291"
      unitRef="pure">0.0189</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000205019_0_BBIndexMember_5YR"
      decimals="INF"
      id="ixv-355292"
      unitRef="pure">-0.0029</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000205019_0_BBIndexMember_LOC"
      decimals="INF"
      id="ixv-355293"
      unitRef="pure">0.0192</oef:AvgAnnlRtrPct>
    <oef:PerfInceptionDate
      contextRef="C000205019_Perf_2018-10-02_ClassMember"
      id="ixv-23793">2018-10-02</oef:PerfInceptionDate>
    <oef:UpdPerfInfoLocationTextBlock contextRef="C000205019_ClassMember" id="ixv-23803">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Visit &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;institutional.fidelity.com&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt; for more recent performance information.&lt;/span&gt;</oef:UpdPerfInfoLocationTextBlock>
    <oef:PerformancePastDoesNotIndicateFuture contextRef="C000205019_ClassMember" id="ixv-23815">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:italic;font-weight:normal;"&gt;The Fund's past performance is not a good predictor of the Fund's future performance.&lt;/span&gt;</oef:PerformancePastDoesNotIndicateFuture>
    <oef:NoDeductionOfTaxesTextBlock contextRef="C000205019_ClassMember" id="ixv-23819">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.&lt;/span&gt;</oef:NoDeductionOfTaxesTextBlock>
    <oef:AddlFundStatisticsTextBlock contextRef="C000205019_ClassMember" id="ixv-23825">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;Key Fund Statistics&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(as of August 31, 2026)&lt;/span&gt;&lt;/div&gt;
&lt;div&gt;&lt;span style="font-size:11px;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;table cellpadding="0" cellspacing="1" style="border-collapse:separate;border-style:none;margin:auto;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:63%; " valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:bold;"&gt;KEY FACTS&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt; &lt;span&gt;&#160;&lt;/span&gt;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fund Size&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;11,833,010,166&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;4,328&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;32,938,746&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="middle"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Portfolio Turnover&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;142&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:AddlFundStatisticsTextBlock>
    <us-gaap:AssetsNet
      contextRef="C000205019_InstantMember"
      decimals="0"
      id="ixv-355294"
      unitRef="usd">11833010166</us-gaap:AssetsNet>
    <oef:HoldingsCount
      contextRef="C000205019_InstantMember"
      decimals="INF"
      id="ixv-355295"
      unitRef="holding">4328</oef:HoldingsCount>
    <oef:AdvisoryFeesPaidAmt
      contextRef="C000205019_ClassMember"
      decimals="0"
      id="ixv-355296"
      unitRef="usd">32938746</oef:AdvisoryFeesPaidAmt>
    <us-gaap:InvestmentCompanyPortfolioTurnover
      contextRef="C000205019_ClassMember"
      decimals="INF"
      id="ixv-355297"
      unitRef="pure">1.42</us-gaap:InvestmentCompanyPortfolioTurnover>
    <oef:HoldingsTableTextBlock contextRef="C000205019_ClassMember" id="ixv-23904">
&#160;
U.S. Government and U.S. Government Agency Obligations

61.0


AAA

5.5


AA

0.9


A

7.7


BBB

15.4


BB

2.9


B

0.8


CCC,CC,C

0.0


Not Rated

9.3




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

U.S. Government and U.S. Government Agency Obligations - 61.0


&#160;

AAA - 5.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

AA - 0.9&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

A - 7.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BBB - 15.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BB - 2.9&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

B - 0.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

CCC,CC,C - 0.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Not Rated - 9.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


Short-Term Investments and Net Other Assets (Liabilities) - (3.5)% 


&#160;


We have used ratings from Moody's Investors Service, Inc. Where Moody's&#xae; ratings are not available, we have used S&amp;P&#xae; ratings. All ratings are as of the date indicated and do not reflect subsequent changes.




&#160;
&#160;
&#160;
&#160;
U.S. Treasury Obligations

44.6


Corporate Bonds

24.3


U.S. Government Agency - Mortgage Securities

16.4


Asset-Backed Securities

9.2


CMOs and Other Mortgage Related Securities

8.7


Preferred Securities

0.2


Other Investments

0.1


Bank Loan Obligations

0.0


Options

0.0




ASSET ALLOCATION (% of Fund's net assets)


&#160;



&#160;

U.S. Treasury Obligations - 44.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Corporate Bonds - 24.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

U.S. Government Agency - Mortgage Securities - 16.4


&#160;

Asset-Backed Securities - 9.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

CMOs and Other Mortgage Related Securities - 8.7


&#160;

Preferred Securities - 0.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Other Investments - 0.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Bank Loan Obligations - 0.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Options - 0.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


Short-Term Investments and Net Other Assets (Liabilities) - (3.5)%


&#160;






United States

91.4


Grand Cayman (UK Overseas Ter)

4.4


Mexico

0.7


Bailiwick Of Jersey

0.7


Ireland

0.6


United Kingdom

0.5


Germany

0.3


Switzerland

0.3


Japan

0.2


Others

0.9




GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

United States - 91.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Grand Cayman (UK Overseas Ter) - 4.4&#160;&#160;&#160;&#160;


&#160;

Mexico - 0.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Bailiwick Of Jersey - 0.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Ireland - 0.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

United Kingdom - 0.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Germany - 0.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Switzerland - 0.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Japan - 0.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Others - 0.9&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;




&#160;




&#160;
&#160;
</oef:HoldingsTableTextBlock>
    <oef:PctOfNav
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      id="ixv-355298"
      unitRef="pure">0.610</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-355299"
      unitRef="pure">0.055</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-355300"
      unitRef="pure">0.009</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
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      unitRef="pure">0.077</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000205019_QD_BBB_Member"
      decimals="INF"
      id="ixv-355302"
      unitRef="pure">0.154</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-355303"
      unitRef="pure">0.029</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000205019_QD_B_Member"
      decimals="INF"
      id="ixv-355304"
      unitRef="pure">0.008</oef:PctOfNav>
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      decimals="INF"
      id="ixv-355305"
      unitRef="pure">0.000</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000205019_QD_NotRated_Member"
      decimals="INF"
      id="ixv-355306"
      unitRef="pure">0.093</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000205019_AA_USTreasuryObligations_Member"
      decimals="INF"
      id="ixv-355307"
      unitRef="pure">0.446</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000205019_AA_CorporateBonds_Member"
      decimals="INF"
      id="ixv-355308"
      unitRef="pure">0.243</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000205019_AA_USGovernmentAgencyMortgageSecurities_Member"
      decimals="INF"
      id="ixv-355309"
      unitRef="pure">0.164</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000205019_AA_AssetBackedSecurities_Member"
      decimals="INF"
      id="ixv-355310"
      unitRef="pure">0.092</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000205019_AA_CMOsandOtherMortgageRelatedSecurities_Member"
      decimals="INF"
      id="ixv-355311"
      unitRef="pure">0.087</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000205019_AA_PreferredSecurities_Member"
      decimals="INF"
      id="ixv-355312"
      unitRef="pure">0.002</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000205019_AA_OtherInvestments_Member"
      decimals="INF"
      id="ixv-355313"
      unitRef="pure">0.001</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000205019_AA_BankLoanObligations_Member"
      decimals="INF"
      id="ixv-355314"
      unitRef="pure">0.000</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000205019_AA_Options_Member"
      decimals="INF"
      id="ixv-355315"
      unitRef="pure">0.000</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000205019_GD_US_Member"
      decimals="INF"
      id="ixv-355316"
      unitRef="pure">0.914</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000205019_GD_GrandCaymanUKOverseasTer_Member"
      decimals="INF"
      id="ixv-355317"
      unitRef="pure">0.044</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000205019_GD_MX_Member"
      decimals="INF"
      id="ixv-355318"
      unitRef="pure">0.007</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000205019_GD_BailiwickOfJersey_Member"
      decimals="INF"
      id="ixv-355319"
      unitRef="pure">0.007</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000205019_GD_IE_Member"
      decimals="INF"
      id="ixv-355320"
      unitRef="pure">0.006</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000205019_GD_GB_Member"
      decimals="INF"
      id="ixv-355321"
      unitRef="pure">0.005</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000205019_GD_DE_Member"
      decimals="INF"
      id="ixv-355322"
      unitRef="pure">0.003</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000205019_GD_CH_Member"
      decimals="INF"
      id="ixv-355323"
      unitRef="pure">0.003</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000205019_GD_JP_Member"
      decimals="INF"
      id="ixv-355324"
      unitRef="pure">0.002</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000205019_GD_Other_Member"
      decimals="INF"
      id="ixv-355325"
      unitRef="pure">0.009</oef:PctOfNav>
    <oef:LargestHoldingsTableTextBlock contextRef="C000205019_ClassMember" id="ixv-24373">TOP HOLDINGS(% of Fund's net assets)

&#160;

&#160;


US Treasury Notes

34.3


&#160;


US Treasury Bonds

10.3


&#160;


Fannie Mae Mortgage pass-thru certificates

5.3


&#160;


Freddie Mac Gold Pool

4.4


&#160;


Ginnie Mae II Pool

3.8


&#160;


Uniform Mortgage Backed Securities

2.4


&#160;


Freddie Mac Multifamily Structured pass-thru certificates

2.2


&#160;


Citigroup Inc

1.2


&#160;


Bank of America Corp

1.1


&#160;


JPMorgan Chase &amp; Co

0.9


&#160;


&#160;

65.9

&#160;



</oef:LargestHoldingsTableTextBlock>
    <oef:PctOfNav
      contextRef="C000205019_TH_0_Member"
      decimals="INF"
      id="ixv-355326"
      unitRef="pure">0.343</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000205019_TH_1_Member"
      decimals="INF"
      id="ixv-355327"
      unitRef="pure">0.103</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000205019_TH_2_Member"
      decimals="INF"
      id="ixv-355328"
      unitRef="pure">0.053</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000205019_TH_3_Member"
      decimals="INF"
      id="ixv-355329"
      unitRef="pure">0.044</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000205019_TH_4_Member"
      decimals="INF"
      id="ixv-355330"
      unitRef="pure">0.038</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000205019_TH_5_Member"
      decimals="INF"
      id="ixv-355331"
      unitRef="pure">0.024</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000205019_TH_6_Member"
      decimals="INF"
      id="ixv-355332"
      unitRef="pure">0.022</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000205019_TH_7_Member"
      decimals="INF"
      id="ixv-355333"
      unitRef="pure">0.012</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000205019_TH_8_Member"
      decimals="INF"
      id="ixv-355334"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000205019_TH_9_Member"
      decimals="INF"
      id="ixv-355335"
      unitRef="pure">0.009</oef:PctOfNav>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-24544">2026-08-31</dei:DocumentPeriodEndDate>
    <oef:FundName contextRef="C000019125_ClassMember" id="ixv-24556">Fidelity&#xae; Investment Grade Bond Fund</oef:FundName>
    <oef:ClassName contextRef="C000019125_ClassMember" id="ixv-24559">Fidelity Advisor&#xae; Investment Grade Bond Fund Class I</oef:ClassName>
    <dei:TradingSymbol contextRef="C000019125_ClassMember" id="ixv-24563">FGBPX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000019125_ClassMember" id="ixv-24582">This annual shareholder report contains information about Fidelity&#xae; Investment Grade Bond Fund for the period September 1, 2025 to August 31, 2026.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000019125_ClassMember" id="ixv-24584">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000019125_ClassMember" id="ixv-24589">You can find additional information about the Fund at fundresearch.fidelity.com/prospectus/sec. You can also request this information by contacting us at 1-877-208-0098 or by sending an e-mail to fidfunddocuments@fidelity.com.</oef:AddlInfoTextBlock>
    <oef:AddlInfoWebsite contextRef="C000019125_ClassMember" id="ixv-24591">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000019125_ClassMember" id="ixv-24594">1-877-208-0098</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000019125_ClassMember" id="ixv-24597">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000019125_ClassMember" id="ixv-24604">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What were your Fund costs for the last year?&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(based on hypothetical $10,000 investment)&lt;/span&gt;&lt;/div&gt;
&lt;div&gt;&lt;span style="font-size:11px;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:bold;"&gt;FUND COST (PREVIOUS YEAR)&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;table cellpadding="0" cellspacing="0" style="border-collapse:collapse;border-style:none;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:51%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:21%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;Costs of a $10,000 investment&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:27%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;Costs paid as a percentage of a $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:51%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;Class I&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:21%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;50&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:27%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;0.50&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:ExpensesTextBlock>
    <oef:ExpensesPaidAmt
      contextRef="C000019125_ClassMember"
      decimals="0"
      id="ixv-355336"
      unitRef="usd">50</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000019125_ClassMember"
      decimals="INF"
      id="ixv-355337"
      unitRef="pure">0.0050</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000019125_ClassMember" id="ixv-24647">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What affected the Fund's performance this period?&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;U.S. taxable investment-grade bonds achieved a gain for the 12 months ending August 31, 2026, buoyed by three policy interest-rate cuts by the Federal Reserve in late 2025, but pulled down since then by rising bond yields amid higher consumer inflation, a resilient economy and heavy U.S. Treasury issuance.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Against this backdrop, the fund's top contributors relative to its benchmark, the Bloomberg U.S. Aggregate Bond Index, for the fiscal year came from overweight allocations to securitized products - specifically, outperforming stakes in asset-backed securities, including AAA-rated collateralized loan obligations, and commercial mortgage-backed securities.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Converserly, the fund's yield-curve positioning and its modestly longer-than-benchmark duration in a rising-rate environment modestly detracted.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;An underweight in agency mortgage-backed securities also modestly hindered performance.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;In terms of security selection, picks in corporate debt, sovereign government bonds and commercial mortgage-backed securities helped.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;The fund's managers did not make significant adjustments in positioning over the period and sought to keep the fund conservatively positioned versus the benchmark.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:FactorsAffectingPerfTextBlock>
    <oef:LineGraphTableTextBlock contextRef="C000019125_ClassMember" id="ixv-24671">How did the Fund perform over the past 10 years?

 &#160;&#160;
CUMULATIVE PERFORMANCE
August 31, 2016 through August 31, 2026. 
Initial investment of $10,000.
Class I


$10,000

$10,131


$10,033


$11,074


$12,025


$12,149


$10,731


$10,657


$11,485


$11,874


$12,051



Bloomberg U.S. Aggregate Bond Index


$10,000

$10,049


$9,944


$10,955


$11,665


$11,655


$10,313


$10,189


$10,933


$11,276


$11,489



&#160;

2016

2017

2018

2019

2020

2021

2022

2023

2024

2025

2026









&#160;
</oef:LineGraphTableTextBlock>
    <oef:LineGraphAndTableMeasureName contextRef="C000019125_LG_ClassMember_11YR" id="ixv-24690">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Class I&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000019125_ClassMember_AsOf_2016"
      decimals="0"
      id="ixv-355338"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019125_ClassMember_AsOf_2017"
      decimals="0"
      id="ixv-355339"
      unitRef="usd">10131</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019125_ClassMember_AsOf_2018"
      decimals="0"
      id="ixv-355340"
      unitRef="usd">10033</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019125_ClassMember_AsOf_2019"
      decimals="0"
      id="ixv-355341"
      unitRef="usd">11074</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019125_ClassMember_AsOf_2020"
      decimals="0"
      id="ixv-355342"
      unitRef="usd">12025</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019125_ClassMember_AsOf_2021"
      decimals="0"
      id="ixv-355343"
      unitRef="usd">12149</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019125_ClassMember_AsOf_2022"
      decimals="0"
      id="ixv-355344"
      unitRef="usd">10731</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019125_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-355345"
      unitRef="usd">10657</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019125_ClassMember_AsOf_2024"
      decimals="0"
      id="ixv-355346"
      unitRef="usd">11485</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019125_ClassMember_AsOf_2025"
      decimals="0"
      id="ixv-355347"
      unitRef="usd">11874</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019125_ClassMember_AsOf_2026"
      decimals="0"
      id="ixv-355348"
      unitRef="usd">12051</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000019125_LG_1_AdditionalIndexMember_11YR"
      id="ixv-24739">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg U.S. Aggregate Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000019125_1_AdditionalIndexMember_AsOf_2016"
      decimals="0"
      id="ixv-355349"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019125_1_AdditionalIndexMember_AsOf_2017"
      decimals="0"
      id="ixv-355350"
      unitRef="usd">10049</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019125_1_AdditionalIndexMember_AsOf_2018"
      decimals="0"
      id="ixv-355351"
      unitRef="usd">9944</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019125_1_AdditionalIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-355352"
      unitRef="usd">10955</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019125_1_AdditionalIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-355353"
      unitRef="usd">11665</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019125_1_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-355354"
      unitRef="usd">11655</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019125_1_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-355355"
      unitRef="usd">10313</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019125_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-355356"
      unitRef="usd">10189</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019125_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-355357"
      unitRef="usd">10933</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019125_1_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-355358"
      unitRef="usd">11276</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019125_1_AdditionalIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-355359"
      unitRef="usd">11489</oef:AccmVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000019125_ClassMember" id="ixv-24840">AVERAGE ANNUAL TOTAL RETURNS:

&#160;

1 Year

5 Year

10 Year


Class I

1.49%

-0.16%

1.88%


Bloomberg U.S. Aggregate Bond Index

1.89%


-0.29%


1.40%




&#160;
&#160;
Visit institutional.fidelity.com for more recent performance information.&#160;

&#160;


The Fund's past performance is not a good predictor of the Fund's future performance. &#160;The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.





</oef:AvgAnnlRtrTableTextBlock>
    <oef:AvgAnnlRtrPct
      contextRef="C000019125_NoLoadClassMember_1YR"
      decimals="INF"
      id="ixv-355360"
      unitRef="pure">0.0149</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019125_NoLoadClassMember_5YR"
      decimals="INF"
      id="ixv-355361"
      unitRef="pure">-0.0016</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019125_NoLoadClassMember_10YR"
      decimals="INF"
      id="ixv-355362"
      unitRef="pure">0.0188</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019125_0_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-355363"
      unitRef="pure">0.0189</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019125_0_BBIndexMember_5YR"
      decimals="INF"
      id="ixv-355364"
      unitRef="pure">-0.0029</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019125_0_BBIndexMember_10YR"
      decimals="INF"
      id="ixv-355365"
      unitRef="pure">0.0140</oef:AvgAnnlRtrPct>
    <oef:UpdPerfInfoLocationTextBlock contextRef="C000019125_ClassMember" id="ixv-24897">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Visit &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;institutional.fidelity.com&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt; for more recent performance information.&lt;/span&gt;</oef:UpdPerfInfoLocationTextBlock>
    <oef:PerformancePastDoesNotIndicateFuture contextRef="C000019125_ClassMember" id="ixv-24909">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:italic;font-weight:normal;"&gt;The Fund's past performance is not a good predictor of the Fund's future performance.&lt;/span&gt;</oef:PerformancePastDoesNotIndicateFuture>
    <oef:NoDeductionOfTaxesTextBlock contextRef="C000019125_ClassMember" id="ixv-24913">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.&lt;/span&gt;</oef:NoDeductionOfTaxesTextBlock>
    <oef:AddlFundStatisticsTextBlock contextRef="C000019125_ClassMember" id="ixv-24919">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;Key Fund Statistics&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(as of August 31, 2026)&lt;/span&gt;&lt;/div&gt;
&lt;div&gt;&lt;span style="font-size:11px;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;table cellpadding="0" cellspacing="1" style="border-collapse:separate;border-style:none;margin:auto;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:63%; " valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:bold;"&gt;KEY FACTS&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt; &lt;span&gt;&#160;&lt;/span&gt;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fund Size&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;11,833,010,166&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;4,328&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;32,938,746&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="middle"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Portfolio Turnover&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;142&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:AddlFundStatisticsTextBlock>
    <us-gaap:AssetsNet
      contextRef="C000019125_InstantMember"
      decimals="0"
      id="ixv-355366"
      unitRef="usd">11833010166</us-gaap:AssetsNet>
    <oef:HoldingsCount
      contextRef="C000019125_InstantMember"
      decimals="INF"
      id="ixv-355367"
      unitRef="holding">4328</oef:HoldingsCount>
    <oef:AdvisoryFeesPaidAmt
      contextRef="C000019125_ClassMember"
      decimals="0"
      id="ixv-355368"
      unitRef="usd">32938746</oef:AdvisoryFeesPaidAmt>
    <us-gaap:InvestmentCompanyPortfolioTurnover
      contextRef="C000019125_ClassMember"
      decimals="INF"
      id="ixv-355369"
      unitRef="pure">1.42</us-gaap:InvestmentCompanyPortfolioTurnover>
    <oef:HoldingsTableTextBlock contextRef="C000019125_ClassMember" id="ixv-24998">
&#160;
U.S. Government and U.S. Government Agency Obligations

61.0


AAA

5.5


AA

0.9


A

7.7


BBB

15.4


BB

2.9


B

0.8


CCC,CC,C

0.0


Not Rated

9.3




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

U.S. Government and U.S. Government Agency Obligations - 61.0


&#160;

AAA - 5.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

AA - 0.9&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

A - 7.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BBB - 15.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BB - 2.9&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

B - 0.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

CCC,CC,C - 0.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Not Rated - 9.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


Short-Term Investments and Net Other Assets (Liabilities) - (3.5)% 


&#160;


We have used ratings from Moody's Investors Service, Inc. Where Moody's&#xae; ratings are not available, we have used S&amp;P&#xae; ratings. All ratings are as of the date indicated and do not reflect subsequent changes.




&#160;
&#160;
&#160;
&#160;
U.S. Treasury Obligations

44.6


Corporate Bonds

24.3


U.S. Government Agency - Mortgage Securities

16.4


Asset-Backed Securities

9.2


CMOs and Other Mortgage Related Securities

8.7


Preferred Securities

0.2


Other Investments

0.1


Bank Loan Obligations

0.0


Options

0.0




ASSET ALLOCATION (% of Fund's net assets)


&#160;



&#160;

U.S. Treasury Obligations - 44.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Corporate Bonds - 24.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

U.S. Government Agency - Mortgage Securities - 16.4


&#160;

Asset-Backed Securities - 9.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

CMOs and Other Mortgage Related Securities - 8.7


&#160;

Preferred Securities - 0.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Other Investments - 0.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Bank Loan Obligations - 0.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Options - 0.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


Short-Term Investments and Net Other Assets (Liabilities) - (3.5)%


&#160;






United States

91.4


Grand Cayman (UK Overseas Ter)

4.4


Mexico

0.7


Bailiwick Of Jersey

0.7


Ireland

0.6


United Kingdom

0.5


Germany

0.3


Switzerland

0.3


Japan

0.2


Others

0.9




GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

United States - 91.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Grand Cayman (UK Overseas Ter) - 4.4&#160;&#160;&#160;&#160;


&#160;

Mexico - 0.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Bailiwick Of Jersey - 0.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Ireland - 0.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

United Kingdom - 0.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Germany - 0.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Switzerland - 0.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Japan - 0.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Others - 0.9&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;




&#160;




&#160;
&#160;
</oef:HoldingsTableTextBlock>
    <oef:PctOfNav
      contextRef="C000019125_QD_USGovernmentandUSGovernmentAgencyObligations_Member"
      decimals="INF"
      id="ixv-355370"
      unitRef="pure">0.610</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019125_QD_AAA_Member"
      decimals="INF"
      id="ixv-355371"
      unitRef="pure">0.055</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019125_QD_AA_Member"
      decimals="INF"
      id="ixv-355372"
      unitRef="pure">0.009</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019125_QD_A_Member"
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      id="ixv-355373"
      unitRef="pure">0.077</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019125_QD_BBB_Member"
      decimals="INF"
      id="ixv-355374"
      unitRef="pure">0.154</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019125_QD_BB_Member"
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      id="ixv-355375"
      unitRef="pure">0.029</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019125_QD_B_Member"
      decimals="INF"
      id="ixv-355376"
      unitRef="pure">0.008</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019125_QD_CCCCCC_Member"
      decimals="INF"
      id="ixv-355377"
      unitRef="pure">0.000</oef:PctOfNav>
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    <oef:LargestHoldingsTableTextBlock contextRef="C000019125_ClassMember" id="ixv-25467">TOP HOLDINGS(% of Fund's net assets)

&#160;

&#160;


US Treasury Notes

34.3


&#160;


US Treasury Bonds

10.3


&#160;


Fannie Mae Mortgage pass-thru certificates

5.3


&#160;


Freddie Mac Gold Pool

4.4


&#160;


Ginnie Mae II Pool

3.8


&#160;


Uniform Mortgage Backed Securities

2.4


&#160;


Freddie Mac Multifamily Structured pass-thru certificates

2.2


&#160;


Citigroup Inc

1.2


&#160;


Bank of America Corp

1.1


&#160;


JPMorgan Chase &amp; Co

0.9


&#160;


&#160;

65.9

&#160;



</oef:LargestHoldingsTableTextBlock>
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      id="ixv-355398"
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    <oef:PctOfNav
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    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-25638">2026-08-31</dei:DocumentPeriodEndDate>
    <oef:FundName contextRef="C000171437_ClassMember" id="ixv-25650">Fidelity&#xae; Short-Term Bond Fund</oef:FundName>
    <oef:ClassName contextRef="C000171437_ClassMember" id="ixv-25653">Fidelity Advisor&#xae; Short-Term Bond Fund Class A</oef:ClassName>
    <dei:TradingSymbol contextRef="C000171437_ClassMember" id="ixv-25657">FBNAX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000171437_ClassMember" id="ixv-25676">This annual shareholder report contains information about Fidelity&#xae; Short-Term Bond Fund for the period September 1, 2025 to August 31, 2026.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000171437_ClassMember" id="ixv-25678">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000171437_ClassMember" id="ixv-25683">You can find additional information about the Fund at fundresearch.fidelity.com/prospectus/sec. You can also request this information by contacting us at 1-877-208-0098 or by sending an e-mail to fidfunddocuments@fidelity.com.</oef:AddlInfoTextBlock>
    <oef:AddlInfoWebsite contextRef="C000171437_ClassMember" id="ixv-25685">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000171437_ClassMember" id="ixv-25688">1-877-208-0098</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000171437_ClassMember" id="ixv-25691">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000171437_ClassMember" id="ixv-25698">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What were your Fund costs for the last year?&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(based on hypothetical $10,000 investment)&lt;/span&gt;&lt;/div&gt;
&lt;div&gt;&lt;span style="font-size:11px;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:bold;"&gt;FUND COST (PREVIOUS YEAR)&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;table cellpadding="0" cellspacing="0" style="border-collapse:collapse;border-style:none;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:51%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:21%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;Costs of a $10,000 investment&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:27%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;Costs paid as a percentage of a $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:51%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;Class A&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:21%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;50&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:27%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;0.50&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:ExpensesTextBlock>
    <oef:ExpensesPaidAmt
      contextRef="C000171437_ClassMember"
      decimals="0"
      id="ixv-355408"
      unitRef="usd">50</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000171437_ClassMember"
      decimals="INF"
      id="ixv-355409"
      unitRef="pure">0.0050</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000171437_ClassMember" id="ixv-25741">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What affected the Fund's performance this period?&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;U.S. taxable investment-grade bonds achieved a gain for the 12 months ending August 31, 2026, buoyed by three policy interest-rate cuts by the Federal Reserve in late 2025, but pulled down since then by rising bond yields amid higher consumer inflation, a resilient economy and heavy U.S. Treasury issuance.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Against this backdrop, the fund's strategy of favoring short-term corporate bonds, while underweighting similar-duration U.S. Treasurys, contributed to its performance versus the benchmark Bloomberg U.S. 1-3 Year Government/Credit Bond Index for the fiscal year. Within corporates, debt holdings among financial institutions, especially banks, added notable value.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Non-benchmark exposure to asset-backed securities, including car loan debt and collateralized loan obligations, also meaningfully helped.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;In contrast, the fund's yield-curve positioning, including the underweighting of one-year maturities in favor of two- and three-year positions, detracted from relative performance.&#160;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;At fiscal year-end, corporates made up about 40% of fund assets, down from 41% a year ago but still notably overweight versus the benchmark average of 22%. Exposure to U.S. Treasurys stood at roughly 43% at the end of the period, up from 35% a year ago and compared with an average of about 72% for the 1-3 year benchmark. Exposure to ABS fell from roughly 18% of assets to about 12% as of August 31.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:FactorsAffectingPerfTextBlock>
    <oef:LineGraphTableTextBlock contextRef="C000171437_ClassMember" id="ixv-25762">How did the Fund perform over the past 10 years?

 &#160;&#160;
CUMULATIVE PERFORMANCE
August 31, 2016 through August 31, 2026. 
Initial investment of $10,000&#160;and the current sales charge was paid.
Class A


$9,850

$9,931


$9,943


$10,354


$10,740


$10,761


$10,289


$10,506


$11,191


$11,715


$11,993



Bloomberg U.S. 1-3 Year Government/Credit Bond Index


$10,000

$10,090


$10,106


$10,572


$10,960


$11,003


$10,565


$10,730


$11,401


$11,930


$12,251



Bloomberg U.S. Aggregate Bond Index


$10,000

$10,049


$9,944


$10,955


$11,665


$11,655


$10,313


$10,189


$10,933


$11,276


$11,489



&#160;

2016

2017

2018

2019

2020

2021

2022

2023

2024

2025

2026









&#160;
</oef:LineGraphTableTextBlock>
    <oef:LineGraphAndTableMeasureName contextRef="C000171437_LG_ClassMember_11YR" id="ixv-25783">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Class A&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000171437_ClassMember_AsOf_2016"
      decimals="0"
      id="ixv-355410"
      unitRef="usd">9850</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171437_ClassMember_AsOf_2017"
      decimals="0"
      id="ixv-355411"
      unitRef="usd">9931</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171437_ClassMember_AsOf_2018"
      decimals="0"
      id="ixv-355412"
      unitRef="usd">9943</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171437_ClassMember_AsOf_2019"
      decimals="0"
      id="ixv-355413"
      unitRef="usd">10354</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171437_ClassMember_AsOf_2020"
      decimals="0"
      id="ixv-355414"
      unitRef="usd">10740</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171437_ClassMember_AsOf_2021"
      decimals="0"
      id="ixv-355415"
      unitRef="usd">10761</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171437_ClassMember_AsOf_2022"
      decimals="0"
      id="ixv-355416"
      unitRef="usd">10289</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171437_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-355417"
      unitRef="usd">10506</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171437_ClassMember_AsOf_2024"
      decimals="0"
      id="ixv-355418"
      unitRef="usd">11191</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171437_ClassMember_AsOf_2025"
      decimals="0"
      id="ixv-355419"
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    <oef:AccmVal
      contextRef="C000171437_ClassMember_AsOf_2026"
      decimals="0"
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      unitRef="usd">11993</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000171437_LG_1_AdditionalIndexMember_11YR"
      id="ixv-25832">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg U.S. 1-3 Year Government/Credit Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000171437_1_AdditionalIndexMember_AsOf_2016"
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      id="ixv-355421"
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    <oef:AccmVal
      contextRef="C000171437_1_AdditionalIndexMember_AsOf_2017"
      decimals="0"
      id="ixv-355422"
      unitRef="usd">10090</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171437_1_AdditionalIndexMember_AsOf_2018"
      decimals="0"
      id="ixv-355423"
      unitRef="usd">10106</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171437_1_AdditionalIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-355424"
      unitRef="usd">10572</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171437_1_AdditionalIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-355425"
      unitRef="usd">10960</oef:AccmVal>
    <oef:AccmVal
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      decimals="0"
      id="ixv-355426"
      unitRef="usd">11003</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171437_1_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-355427"
      unitRef="usd">10565</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171437_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-355428"
      unitRef="usd">10730</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171437_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-355429"
      unitRef="usd">11401</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171437_1_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-355430"
      unitRef="usd">11930</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171437_1_AdditionalIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-355431"
      unitRef="usd">12251</oef:AccmVal>
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      contextRef="C000171437_LG_2_AdditionalIndexMember_11YR"
      id="ixv-25881">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg U.S. Aggregate Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000171437_2_AdditionalIndexMember_AsOf_2016"
      decimals="0"
      id="ixv-355432"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
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      id="ixv-355433"
      unitRef="usd">10049</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171437_2_AdditionalIndexMember_AsOf_2018"
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      id="ixv-355434"
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    <oef:AccmVal
      contextRef="C000171437_2_AdditionalIndexMember_AsOf_2019"
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      id="ixv-355435"
      unitRef="usd">10955</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171437_2_AdditionalIndexMember_AsOf_2020"
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      id="ixv-355436"
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    <oef:AccmVal
      contextRef="C000171437_2_AdditionalIndexMember_AsOf_2021"
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      id="ixv-355437"
      unitRef="usd">11655</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171437_2_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-355438"
      unitRef="usd">10313</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171437_2_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-355439"
      unitRef="usd">10189</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171437_2_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-355440"
      unitRef="usd">10933</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171437_2_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-355441"
      unitRef="usd">11276</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000171437_2_AdditionalIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-355442"
      unitRef="usd">11489</oef:AccmVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000171437_ClassMember" id="ixv-25982">AVERAGE ANNUAL TOTAL RETURNS:

&#160;

1 Year

5 Year

10 Year


Class A (incl. 1.50% sales charge) &#160;

0.84%

1.88%


1.83%


Class A (without 1.50% sales charge)

2.38%

2.19%

1.99%


Bloomberg U.S. 1-3 Year Government/Credit Bond Index

2.69%


2.17%


2.05%


Bloomberg U.S. Aggregate Bond Index

1.89%


-0.29%


1.40%




&#160;
&#160;
Visit institutional.fidelity.com for more recent performance information.&#160;

&#160;


The Fund's past performance is not a good predictor of the Fund's future performance. &#160;The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.





</oef:AvgAnnlRtrTableTextBlock>
    <oef:AvgAnnlRtrPct
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      id="ixv-355445"
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      decimals="INF"
      id="ixv-355446"
      unitRef="pure">0.0238</oef:AvgAnnlRtrPct>
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      id="ixv-355447"
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      id="ixv-355448"
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      id="ixv-355452"
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      id="ixv-355453"
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      decimals="INF"
      id="ixv-355454"
      unitRef="pure">0.0140</oef:AvgAnnlRtrPct>
    <oef:UpdPerfInfoLocationTextBlock contextRef="C000171437_ClassMember" id="ixv-26068">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Visit &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;institutional.fidelity.com&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt; for more recent performance information.&lt;/span&gt;</oef:UpdPerfInfoLocationTextBlock>
    <oef:PerformancePastDoesNotIndicateFuture contextRef="C000171437_ClassMember" id="ixv-26080">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:italic;font-weight:normal;"&gt;The Fund's past performance is not a good predictor of the Fund's future performance.&lt;/span&gt;</oef:PerformancePastDoesNotIndicateFuture>
    <oef:NoDeductionOfTaxesTextBlock contextRef="C000171437_ClassMember" id="ixv-26084">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.&lt;/span&gt;</oef:NoDeductionOfTaxesTextBlock>
    <oef:AddlFundStatisticsTextBlock contextRef="C000171437_ClassMember" id="ixv-26090">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;Key Fund Statistics&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(as of August 31, 2026)&lt;/span&gt;&lt;/div&gt;
&lt;div&gt;&lt;span style="font-size:11px;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;table cellpadding="0" cellspacing="1" style="border-collapse:separate;border-style:none;margin:auto;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:63%; " valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:bold;"&gt;KEY FACTS&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt; &lt;span&gt;&#160;&lt;/span&gt;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fund Size&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;2,843,357,688&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;483&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;5,198,445&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="middle"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Portfolio Turnover&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;95&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:AddlFundStatisticsTextBlock>
    <us-gaap:AssetsNet
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      unitRef="usd">2843357688</us-gaap:AssetsNet>
    <oef:HoldingsCount
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    <oef:HoldingsTableTextBlock contextRef="C000171437_ClassMember" id="ixv-26165">
&#160;
U.S. Government and U.S. Government Agency Obligations

43.3


AAA

9.9


AA

1.2


A

21.3


BBB

16.6


BB

1.4


Not Rated

5.8


Short-Term Investments and Net Other Assets (Liabilities)

0.5




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

U.S. Government and U.S. Government Agency Obligations - 43.3


&#160;

AAA - 9.9&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

AA - 1.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

A - 21.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BBB - 16.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BB - 1.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Not Rated - 5.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Short-Term Investments and Net Other Assets (Liabilities) - 0.5


&#160;


We have used ratings from Moody's Investors Service, Inc. Where Moody's&#xae; ratings are not available, we have used S&amp;P&#xae; ratings. All ratings are as of the date indicated and do not reflect subsequent changes.




&#160;
&#160;
&#160;
&#160;
U.S. Treasury Obligations

43.1


Corporate Bonds

39.1


Asset-Backed Securities

12.3


CMOs and Other Mortgage Related Securities

4.2


Other Investments

0.4


U.S. Government Agency - Mortgage Securities

0.2


Foreign Government and Government Agency Obligations

0.2


Short-Term Investments and Net Other Assets (Liabilities)

0.5




ASSET ALLOCATION (% of Fund's net assets)


&#160;



&#160;

U.S. Treasury Obligations - 43.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Corporate Bonds - 39.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Asset-Backed Securities - 12.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

CMOs and Other Mortgage Related Securities - 4.2


&#160;

Other Investments - 0.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

U.S. Government Agency - Mortgage Securities - 0.2


&#160;

Foreign Government and Government Agency Obligations - 0.2


&#160;

Short-Term Investments and Net Other Assets (Liabilities) - 0.5


&#160;






United States

78.6


Grand Cayman (UK Overseas Ter)

4.3


United Kingdom

3.6


Canada

2.8


Germany

2.7


France

1.4


Bailiwick Of Jersey

1.2


Ireland

1.1


Japan

1.0


Others

3.3




GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

United States - 78.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Grand Cayman (UK Overseas Ter) - 4.3&#160;&#160;&#160;&#160;


&#160;

United Kingdom - 3.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Canada - 2.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Germany - 2.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

France - 1.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Bailiwick Of Jersey - 1.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Ireland - 1.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Japan - 1.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Others - 3.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;




&#160;




&#160;
&#160;
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      id="ixv-355469"
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      id="ixv-355470"
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      decimals="INF"
      id="ixv-355473"
      unitRef="pure">0.002</oef:PctOfNav>
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      id="ixv-355474"
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      unitRef="pure">0.786</oef:PctOfNav>
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      id="ixv-355476"
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    <oef:PctOfNav
      contextRef="C000171437_GD_GB_Member"
      decimals="INF"
      id="ixv-355477"
      unitRef="pure">0.036</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000171437_GD_CA_Member"
      decimals="INF"
      id="ixv-355478"
      unitRef="pure">0.028</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000171437_GD_DE_Member"
      decimals="INF"
      id="ixv-355479"
      unitRef="pure">0.027</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000171437_GD_FR_Member"
      decimals="INF"
      id="ixv-355480"
      unitRef="pure">0.014</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000171437_GD_BailiwickOfJersey_Member"
      decimals="INF"
      id="ixv-355481"
      unitRef="pure">0.012</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000171437_GD_IE_Member"
      decimals="INF"
      id="ixv-355482"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000171437_GD_JP_Member"
      decimals="INF"
      id="ixv-355483"
      unitRef="pure">0.010</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000171437_GD_Other_Member"
      decimals="INF"
      id="ixv-355484"
      unitRef="pure">0.033</oef:PctOfNav>
    <oef:LargestHoldingsTableTextBlock contextRef="C000171437_ClassMember" id="ixv-26600">TOP HOLDINGS(% of Fund's net assets)

&#160;

&#160;


US Treasury Notes

43.1


&#160;


Bank of America Corp

1.4


&#160;


JPMorgan Chase &amp; Co

1.3


&#160;


Wells Fargo &amp; Co

1.2


&#160;


Goldman Sachs Group Inc/The

1.0


&#160;


Citigroup Inc

0.9


&#160;


Deutsche Bank AG/New York NY

0.9


&#160;


General Motors Financial Co Inc

0.9


&#160;


Barclays PLC

0.8


&#160;


HSBC Holdings PLC

0.8


&#160;


&#160;

52.3

&#160;



</oef:LargestHoldingsTableTextBlock>
    <oef:PctOfNav
      contextRef="C000171437_TH_0_Member"
      decimals="INF"
      id="ixv-355485"
      unitRef="pure">0.431</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000171437_TH_1_Member"
      decimals="INF"
      id="ixv-355486"
      unitRef="pure">0.014</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000171437_TH_2_Member"
      decimals="INF"
      id="ixv-355487"
      unitRef="pure">0.013</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000171437_TH_3_Member"
      decimals="INF"
      id="ixv-355488"
      unitRef="pure">0.012</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000171437_TH_4_Member"
      decimals="INF"
      id="ixv-355489"
      unitRef="pure">0.010</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000171437_TH_5_Member"
      decimals="INF"
      id="ixv-355490"
      unitRef="pure">0.009</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000171437_TH_6_Member"
      decimals="INF"
      id="ixv-355491"
      unitRef="pure">0.009</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000171437_TH_7_Member"
      decimals="INF"
      id="ixv-355492"
      unitRef="pure">0.009</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000171437_TH_8_Member"
      decimals="INF"
      id="ixv-355493"
      unitRef="pure">0.008</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000171437_TH_9_Member"
      decimals="INF"
      id="ixv-355494"
      unitRef="pure">0.008</oef:PctOfNav>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-26771">2026-08-31</dei:DocumentPeriodEndDate>
    <oef:FundName contextRef="C000019120_ClassMember" id="ixv-26783">Fidelity&#xae; Investment Grade Bond Fund</oef:FundName>
    <oef:ClassName contextRef="C000019120_ClassMember" id="ixv-26786">Fidelity&#xae; Investment Grade Bond Fund</oef:ClassName>
    <dei:TradingSymbol contextRef="C000019120_ClassMember" id="ixv-26790">FBNDX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000019120_ClassMember" id="ixv-26809">This annual shareholder report contains information about Fidelity&#xae; Investment Grade Bond Fund for the period September 1, 2025 to August 31, 2026.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000019120_ClassMember" id="ixv-26811">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000019120_ClassMember" id="ixv-26816">You can find additional information about the Fund at fundresearch.fidelity.com/prospectus/sec. You can also request this information by contacting us at 1-800-544-8544 or by sending an e-mail to fidfunddocuments@fidelity.com.</oef:AddlInfoTextBlock>
    <oef:AddlInfoWebsite contextRef="C000019120_ClassMember" id="ixv-26818">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000019120_ClassMember" id="ixv-26821">1-800-544-8544</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000019120_ClassMember" id="ixv-26824">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000019120_ClassMember" id="ixv-26831">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What were your Fund costs for the last year?&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(based on hypothetical $10,000 investment)&lt;/span&gt;&lt;/div&gt;
&lt;div&gt;&lt;span style="font-size:11px;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:bold;"&gt;FUND COST (PREVIOUS YEAR)&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;table cellpadding="0" cellspacing="0" style="border-collapse:collapse;border-style:none;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:51%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:21%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;Costs of a $10,000 investment&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:27%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;Costs paid as a percentage of a $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:51%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity&#xae; Investment Grade Bond Fund&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:21%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;45&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:27%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;0.45&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:ExpensesTextBlock>
    <oef:ExpensesPaidAmt
      contextRef="C000019120_ClassMember"
      decimals="0"
      id="ixv-355495"
      unitRef="usd">45</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000019120_ClassMember"
      decimals="INF"
      id="ixv-355496"
      unitRef="pure">0.0045</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000019120_ClassMember" id="ixv-26874">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What affected the Fund's performance this period?&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;U.S. taxable investment-grade bonds achieved a gain for the 12 months ending August 31, 2026, buoyed by three policy interest-rate cuts by the Federal Reserve in late 2025, but pulled down since then by rising bond yields amid higher consumer inflation, a resilient economy and heavy U.S. Treasury issuance.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Against this backdrop, the fund's top contributors relative to its benchmark, the Bloomberg U.S. Aggregate Bond Index, for the fiscal year came from overweight allocations to securitized products - specifically, outperforming stakes in asset-backed securities, including AAA-rated collateralized loan obligations, and commercial mortgage-backed securities.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Converserly, the fund's yield-curve positioning and its modestly longer-than-benchmark duration in a rising-rate environment modestly detracted.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;An underweight in agency mortgage-backed securities also modestly hindered performance.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;In terms of security selection, picks in corporate debt, sovereign government bonds and commercial mortgage-backed securities helped.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;The fund's managers did not make significant adjustments in positioning over the period and sought to keep the fund conservatively positioned versus the benchmark.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:FactorsAffectingPerfTextBlock>
    <oef:LineGraphTableTextBlock contextRef="C000019120_ClassMember" id="ixv-26898">How did the Fund perform over the past 10 years?

 &#160;&#160;
CUMULATIVE PERFORMANCE
August 31, 2016 through August 31, 2026. 
Initial investment of $10,000.
Fidelity&#xae; Investment Grade Bond Fund


$10,000

$10,136


$10,042


$11,091


$12,047


$12,177


$10,774


$10,690


$11,527


$11,923


$12,106



Bloomberg U.S. Aggregate Bond Index


$10,000

$10,049


$9,944


$10,955


$11,665


$11,655


$10,313


$10,189


$10,933


$11,276


$11,489



&#160;

2016

2017

2018

2019

2020

2021

2022

2023

2024

2025

2026









&#160;
</oef:LineGraphTableTextBlock>
    <oef:LineGraphAndTableMeasureName contextRef="C000019120_LG_ClassMember_11YR" id="ixv-26917">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity&#xae; Investment Grade Bond Fund&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000019120_ClassMember_AsOf_2016"
      decimals="0"
      id="ixv-355497"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019120_ClassMember_AsOf_2017"
      decimals="0"
      id="ixv-355498"
      unitRef="usd">10136</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019120_ClassMember_AsOf_2018"
      decimals="0"
      id="ixv-355499"
      unitRef="usd">10042</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019120_ClassMember_AsOf_2019"
      decimals="0"
      id="ixv-355500"
      unitRef="usd">11091</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019120_ClassMember_AsOf_2020"
      decimals="0"
      id="ixv-355501"
      unitRef="usd">12047</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019120_ClassMember_AsOf_2021"
      decimals="0"
      id="ixv-355502"
      unitRef="usd">12177</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019120_ClassMember_AsOf_2022"
      decimals="0"
      id="ixv-355503"
      unitRef="usd">10774</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019120_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-355504"
      unitRef="usd">10690</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019120_ClassMember_AsOf_2024"
      decimals="0"
      id="ixv-355505"
      unitRef="usd">11527</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019120_ClassMember_AsOf_2025"
      decimals="0"
      id="ixv-355506"
      unitRef="usd">11923</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019120_ClassMember_AsOf_2026"
      decimals="0"
      id="ixv-355507"
      unitRef="usd">12106</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000019120_LG_1_AdditionalIndexMember_11YR"
      id="ixv-26966">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg U.S. Aggregate Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000019120_1_AdditionalIndexMember_AsOf_2016"
      decimals="0"
      id="ixv-355508"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019120_1_AdditionalIndexMember_AsOf_2017"
      decimals="0"
      id="ixv-355509"
      unitRef="usd">10049</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019120_1_AdditionalIndexMember_AsOf_2018"
      decimals="0"
      id="ixv-355510"
      unitRef="usd">9944</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019120_1_AdditionalIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-355511"
      unitRef="usd">10955</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019120_1_AdditionalIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-355512"
      unitRef="usd">11665</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019120_1_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-355513"
      unitRef="usd">11655</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019120_1_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-355514"
      unitRef="usd">10313</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019120_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-355515"
      unitRef="usd">10189</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019120_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-355516"
      unitRef="usd">10933</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019120_1_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-355517"
      unitRef="usd">11276</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019120_1_AdditionalIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-355518"
      unitRef="usd">11489</oef:AccmVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000019120_ClassMember" id="ixv-27067">AVERAGE ANNUAL TOTAL RETURNS:

&#160;

1 Year

5 Year

10 Year


Fidelity&#xae; Investment Grade Bond Fund

1.54%

-0.12%

1.93%


Bloomberg U.S. Aggregate Bond Index

1.89%


-0.29%


1.40%




&#160;
&#160;
Visit www.fidelity.com for more recent performance information.&#160;

&#160;


The Fund's past performance is not a good predictor of the Fund's future performance. &#160;The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.





</oef:AvgAnnlRtrTableTextBlock>
    <oef:AvgAnnlRtrPct
      contextRef="C000019120_NoLoadClassMember_1YR"
      decimals="INF"
      id="ixv-355519"
      unitRef="pure">0.0154</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019120_NoLoadClassMember_5YR"
      decimals="INF"
      id="ixv-355520"
      unitRef="pure">-0.0012</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019120_NoLoadClassMember_10YR"
      decimals="INF"
      id="ixv-355521"
      unitRef="pure">0.0193</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019120_0_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-355522"
      unitRef="pure">0.0189</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019120_0_BBIndexMember_5YR"
      decimals="INF"
      id="ixv-355523"
      unitRef="pure">-0.0029</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019120_0_BBIndexMember_10YR"
      decimals="INF"
      id="ixv-355524"
      unitRef="pure">0.0140</oef:AvgAnnlRtrPct>
    <oef:UpdPerfInfoLocationTextBlock contextRef="C000019120_ClassMember" id="ixv-27124">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Visit &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;www.fidelity.com&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt; for more recent performance information.&lt;/span&gt;</oef:UpdPerfInfoLocationTextBlock>
    <oef:PerformancePastDoesNotIndicateFuture contextRef="C000019120_ClassMember" id="ixv-27136">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:italic;font-weight:normal;"&gt;The Fund's past performance is not a good predictor of the Fund's future performance.&lt;/span&gt;</oef:PerformancePastDoesNotIndicateFuture>
    <oef:NoDeductionOfTaxesTextBlock contextRef="C000019120_ClassMember" id="ixv-27140">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.&lt;/span&gt;</oef:NoDeductionOfTaxesTextBlock>
    <oef:AddlFundStatisticsTextBlock contextRef="C000019120_ClassMember" id="ixv-27146">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;Key Fund Statistics&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(as of August 31, 2026)&lt;/span&gt;&lt;/div&gt;
&lt;div&gt;&lt;span style="font-size:11px;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;table cellpadding="0" cellspacing="1" style="border-collapse:separate;border-style:none;margin:auto;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:63%; " valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:bold;"&gt;KEY FACTS&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt; &lt;span&gt;&#160;&lt;/span&gt;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fund Size&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;11,833,010,166&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;4,328&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;32,938,746&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="middle"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Portfolio Turnover&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;142&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:AddlFundStatisticsTextBlock>
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      decimals="0"
      id="ixv-355525"
      unitRef="usd">11833010166</us-gaap:AssetsNet>
    <oef:HoldingsCount
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      decimals="INF"
      id="ixv-355526"
      unitRef="holding">4328</oef:HoldingsCount>
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      decimals="0"
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      unitRef="usd">32938746</oef:AdvisoryFeesPaidAmt>
    <us-gaap:InvestmentCompanyPortfolioTurnover
      contextRef="C000019120_ClassMember"
      decimals="INF"
      id="ixv-355528"
      unitRef="pure">1.42</us-gaap:InvestmentCompanyPortfolioTurnover>
    <oef:HoldingsTableTextBlock contextRef="C000019120_ClassMember" id="ixv-27225">
&#160;
U.S. Government and U.S. Government Agency Obligations

61.0


AAA

5.5


AA

0.9


A

7.7


BBB

15.4


BB

2.9


B

0.8


CCC,CC,C

0.0


Not Rated

9.3




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

U.S. Government and U.S. Government Agency Obligations - 61.0


&#160;

AAA - 5.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

AA - 0.9&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

A - 7.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BBB - 15.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BB - 2.9&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

B - 0.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

CCC,CC,C - 0.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Not Rated - 9.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


Short-Term Investments and Net Other Assets (Liabilities) - (3.5)% 


&#160;


We have used ratings from Moody's Investors Service, Inc. Where Moody's&#xae; ratings are not available, we have used S&amp;P&#xae; ratings. All ratings are as of the date indicated and do not reflect subsequent changes.




&#160;
&#160;
&#160;
&#160;
U.S. Treasury Obligations

44.6


Corporate Bonds

24.3


U.S. Government Agency - Mortgage Securities

16.4


Asset-Backed Securities

9.2


CMOs and Other Mortgage Related Securities

8.7


Preferred Securities

0.2


Other Investments

0.1


Bank Loan Obligations

0.0


Options

0.0




ASSET ALLOCATION (% of Fund's net assets)


&#160;



&#160;

U.S. Treasury Obligations - 44.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Corporate Bonds - 24.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

U.S. Government Agency - Mortgage Securities - 16.4


&#160;

Asset-Backed Securities - 9.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

CMOs and Other Mortgage Related Securities - 8.7


&#160;

Preferred Securities - 0.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Other Investments - 0.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Bank Loan Obligations - 0.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Options - 0.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


Short-Term Investments and Net Other Assets (Liabilities) - (3.5)%


&#160;






United States

91.4


Grand Cayman (UK Overseas Ter)

4.4


Mexico

0.7


Bailiwick Of Jersey

0.7


Ireland

0.6


United Kingdom

0.5


Germany

0.3


Switzerland

0.3


Japan

0.2


Others

0.9




GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

United States - 91.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Grand Cayman (UK Overseas Ter) - 4.4&#160;&#160;&#160;&#160;


&#160;

Mexico - 0.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Bailiwick Of Jersey - 0.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Ireland - 0.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

United Kingdom - 0.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Germany - 0.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Switzerland - 0.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Japan - 0.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Others - 0.9&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;




&#160;




&#160;
&#160;
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      decimals="INF"
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    <oef:LargestHoldingsTableTextBlock contextRef="C000019120_ClassMember" id="ixv-27694">TOP HOLDINGS(% of Fund's net assets)

&#160;

&#160;


US Treasury Notes

34.3


&#160;


US Treasury Bonds

10.3


&#160;


Fannie Mae Mortgage pass-thru certificates

5.3


&#160;


Freddie Mac Gold Pool

4.4


&#160;


Ginnie Mae II Pool

3.8


&#160;


Uniform Mortgage Backed Securities

2.4


&#160;


Freddie Mac Multifamily Structured pass-thru certificates

2.2


&#160;


Citigroup Inc

1.2


&#160;


Bank of America Corp

1.1


&#160;


JPMorgan Chase &amp; Co

0.9


&#160;


&#160;

65.9

&#160;



</oef:LargestHoldingsTableTextBlock>
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      id="ixv-355557"
      unitRef="pure">0.343</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
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      unitRef="pure">0.103</oef:PctOfNav>
    <oef:PctOfNav
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      unitRef="pure">0.011</oef:PctOfNav>
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    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-27865">2026-08-31</dei:DocumentPeriodEndDate>
    <oef:FundName contextRef="C000276223_ClassMember" id="ixv-27877">Fidelity&#xae; Short-Term Bond Fund</oef:FundName>
    <oef:ClassName contextRef="C000276223_ClassMember" id="ixv-27880">Fidelity&#xae; Short-Term Bond Fund ETF Class</oef:ClassName>
    <dei:TradingSymbol contextRef="C000276223_ClassMember" id="ixv-27884">FSTB</dei:TradingSymbol>
    <dei:SecurityExchangeName contextRef="C000276223_ClassMember" id="ixv-355567">NASDAQ</dei:SecurityExchangeName>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000276223_ClassMember" id="ixv-27905">This annual shareholder report contains information about Fidelity&#xae; Short-Term Bond Fund for the period June 16, 2026 to August 31, 2026.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000276223_ClassMember" id="ixv-27907">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000276223_ClassMember" id="ixv-27912">You can find additional information about the Fund at fundresearch.fidelity.com/prospectus/sec. You can also request this information by contacting us at 1-800-FIDELITY or by sending an e-mail to fidfunddocuments@fidelity.com.</oef:AddlInfoTextBlock>
    <oef:AddlInfoWebsite contextRef="C000276223_ClassMember" id="ixv-27914">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000276223_ClassMember" id="ixv-27917">1-800-FIDELITY</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000276223_ClassMember" id="ixv-27920">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000276223_ClassMember" id="ixv-27927">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What were your Fund costs for the last year?&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(based on hypothetical $10,000 investment)&lt;/span&gt;&lt;/div&gt;
&lt;div&gt;&lt;span style="font-size:11px;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:bold;"&gt;FUND COST (PREVIOUS YEAR)&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;table cellpadding="0" cellspacing="0" style="border-collapse:collapse;border-style:none;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:51%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:21%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;Costs of a $10,000 investment&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:27%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;Costs paid as a percentage of a $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:51%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;ETF Class&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:6px;color:#000000;font-style:normal;vertical-align:4px;font-weight:normal;"&gt;A&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:21%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;4&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:27%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;0.20&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:6px;color:#000000;font-style:normal;vertical-align:4px;font-weight:normal;"&gt;A&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans Cd';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Expenses for the full reporting period would be higher.&lt;/span&gt;&lt;/div&gt;
&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:ExpensesTextBlock>
    <oef:ExpensesPaidAmt
      contextRef="C000276223_ClassMember"
      decimals="0"
      id="ixv-355568"
      unitRef="usd">4</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000276223_ClassMember"
      decimals="INF"
      id="ixv-355569"
      unitRef="pure">0.0020</oef:ExpenseRatioPct>
    <oef:ExpensesShortPeriodFnTextBlock contextRef="C000276223_ClassMember" id="ixv-27971">Expenses for the full reporting period would be higher.</oef:ExpensesShortPeriodFnTextBlock>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000276223_ClassMember" id="ixv-27977">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What affected the Fund's performance this period?&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;U.S. taxable investment-grade bonds achieved a gain for the 12 months ending August 31, 2026, buoyed by three policy interest-rate cuts by the Federal Reserve in late 2025, but pulled down since then by rising bond yields amid higher consumer inflation, a resilient economy and heavy U.S. Treasury issuance.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Against this backdrop, the fund's strategy of favoring short-term corporate bonds, while underweighting similar-duration U.S. Treasurys, contributed to its performance versus the benchmark Bloomberg U.S. 1-3 Year Government/Credit Bond Index for the fiscal year. Within corporates, debt holdings among financial institutions, especially banks, added notable value.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Non-benchmark exposure to asset-backed securities, including car loan debt and collateralized loan obligations, also meaningfully helped.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;In contrast, the fund's yield-curve positioning, including the underweighting of one-year maturities in favor of two- and three-year positions, detracted from relative performance.&#160;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;At fiscal year-end, corporates made up about 40% of fund assets, down from 41% a year ago but still notably overweight versus the benchmark average of 22%. Exposure to U.S. Treasurys stood at roughly 43% at the end of the period, up from 35% a year ago and compared with an average of about 72% for the 1-3 year benchmark. Exposure to ABS fell from roughly 18% of assets to about 12% as of August 31.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:FactorsAffectingPerfTextBlock>
    <oef:AddlFundStatisticsTextBlock contextRef="C000276223_ClassMember" id="ixv-28004">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;Key Fund Statistics&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(as of August 31, 2026)&lt;/span&gt;&lt;/div&gt;
&lt;div&gt;&lt;span style="font-size:11px;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;table cellpadding="0" cellspacing="1" style="border-collapse:separate;border-style:none;margin:auto;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:63%; " valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:bold;"&gt;KEY FACTS&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt; &lt;span&gt;&#160;&lt;/span&gt;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fund Size&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;2,843,357,688&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;483&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;5,198,445&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="middle"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Portfolio Turnover&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;95&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:AddlFundStatisticsTextBlock>
    <us-gaap:AssetsNet
      contextRef="C000276223_InstantMember"
      decimals="0"
      id="ixv-355570"
      unitRef="usd">2843357688</us-gaap:AssetsNet>
    <oef:HoldingsCount
      contextRef="C000276223_InstantMember"
      decimals="INF"
      id="ixv-355571"
      unitRef="holding">483</oef:HoldingsCount>
    <oef:AdvisoryFeesPaidAmt
      contextRef="C000276223_ClassMember"
      decimals="0"
      id="ixv-355572"
      unitRef="usd">5198445</oef:AdvisoryFeesPaidAmt>
    <us-gaap:InvestmentCompanyPortfolioTurnover
      contextRef="C000276223_ClassMember"
      decimals="INF"
      id="ixv-355573"
      unitRef="pure">0.95</us-gaap:InvestmentCompanyPortfolioTurnover>
    <oef:HoldingsTableTextBlock contextRef="C000276223_ClassMember" id="ixv-28079">
&#160;
U.S. Government and U.S. Government Agency Obligations

43.3


AAA

9.9


AA

1.2


A

21.3


BBB

16.6


BB

1.4


Not Rated

5.8


Short-Term Investments and Net Other Assets (Liabilities)

0.5




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

U.S. Government and U.S. Government Agency Obligations - 43.3


&#160;

AAA - 9.9&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

AA - 1.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

A - 21.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BBB - 16.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BB - 1.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Not Rated - 5.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Short-Term Investments and Net Other Assets (Liabilities) - 0.5


&#160;


We have used ratings from Moody's Investors Service, Inc. Where Moody's&#xae; ratings are not available, we have used S&amp;P&#xae; ratings. All ratings are as of the date indicated and do not reflect subsequent changes.




&#160;
&#160;
&#160;
&#160;
U.S. Treasury Obligations

43.1


Corporate Bonds

39.1


Asset-Backed Securities

12.3


CMOs and Other Mortgage Related Securities

4.2


Other Investments

0.4


U.S. Government Agency - Mortgage Securities

0.2


Foreign Government and Government Agency Obligations

0.2


Short-Term Investments and Net Other Assets (Liabilities)

0.5




ASSET ALLOCATION (% of Fund's net assets)


&#160;



&#160;

U.S. Treasury Obligations - 43.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Corporate Bonds - 39.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Asset-Backed Securities - 12.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

CMOs and Other Mortgage Related Securities - 4.2


&#160;

Other Investments - 0.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

U.S. Government Agency - Mortgage Securities - 0.2


&#160;

Foreign Government and Government Agency Obligations - 0.2


&#160;

Short-Term Investments and Net Other Assets (Liabilities) - 0.5


&#160;






United States

78.6


Grand Cayman (UK Overseas Ter)

4.3


United Kingdom

3.6


Canada

2.8


Germany

2.7


France

1.4


Bailiwick Of Jersey

1.2


Ireland

1.1


Japan

1.0


Others

3.3




GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

United States - 78.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Grand Cayman (UK Overseas Ter) - 4.3&#160;&#160;&#160;&#160;


&#160;

United Kingdom - 3.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Canada - 2.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Germany - 2.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

France - 1.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Bailiwick Of Jersey - 1.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Ireland - 1.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Japan - 1.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Others - 3.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;




&#160;




&#160;
&#160;
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    <oef:LargestHoldingsTableTextBlock contextRef="C000276223_ClassMember" id="ixv-28514">TOP HOLDINGS(% of Fund's net assets)

&#160;

&#160;


US Treasury Notes

43.1


&#160;


Bank of America Corp

1.4


&#160;


JPMorgan Chase &amp; Co

1.3


&#160;


Wells Fargo &amp; Co

1.2


&#160;


Goldman Sachs Group Inc/The

1.0


&#160;


Citigroup Inc

0.9


&#160;


Deutsche Bank AG/New York NY

0.9


&#160;


General Motors Financial Co Inc

0.9


&#160;


Barclays PLC

0.8


&#160;


HSBC Holdings PLC

0.8


&#160;


&#160;

52.3

&#160;



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