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    <unit id="usd">
        <measure>iso4217:USD</measure>
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        <measure>pure</measure>
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        <measure>shares</measure>
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    <oef:MaterialFundChngNoticeTextBlock contextRef="C000182864_ClassMember" id="ixv-104">This report describes changes to the Fund that occurred during the reporting period.</oef:MaterialFundChngNoticeTextBlock>
    <oef:FundName contextRef="C000182864_ClassMember" id="ixv-115">Fidelity&#xae; Total Bond K6 Fund</oef:FundName>
    <oef:ClassName contextRef="C000182864_ClassMember" id="ixv-118">Fidelity&#xae; Total Bond K6 Fund</oef:ClassName>
    <dei:TradingSymbol contextRef="C000182864_ClassMember" id="ixv-122">FTKFX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000182864_ClassMember" id="ixv-141">This annual shareholder report contains information about Fidelity&#xae; Total Bond K6 Fund for the period September 1, 2025 to August 31, 2026.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000182864_ClassMember" id="ixv-143">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000182864_ClassMember" id="ixv-148">You can find additional information about the Fund at fundresearch.fidelity.com/prospectus/sec. You can also request this information by contacting us at 1-800-835-5092 or by sending an e-mail to fidfunddocuments@fidelity.com.</oef:AddlInfoTextBlock>
    <oef:AddlInfoWebsite contextRef="C000182864_ClassMember" id="ixv-150">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000182864_ClassMember" id="ixv-153">1-800-835-5092</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000182864_ClassMember" id="ixv-156">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000182864_ClassMember" id="ixv-163">&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 $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:51%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity&#xae; Total Bond K6 Fund&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:21%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&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="C000182864_ClassMember"
      decimals="0"
      id="ixv-306927"
      unitRef="usd">30</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000182864_ClassMember"
      decimals="INF"
      id="ixv-306928"
      unitRef="pure">0.0030</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000182864_ClassMember" id="ixv-206">&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="C000182864_ClassMember" id="ixv-233">How did the Fund perform over the life of Fund?

 &#160;&#160;
CUMULATIVE PERFORMANCE
May 25, 2017 through August 31, 2026. 
Initial investment of $10,000.
Fidelity&#xae; Total Bond K6 Fund


$10,000

$10,135


$10,068


$11,046


$11,905


$12,206


$10,854


$10,882


$11,779


$12,235



Bloomberg U.S. Aggregate Bond Index


$10,000

$10,154


$10,047


$11,070


$11,786


$11,776


$10,420


$10,296


$11,047


$11,393



&#160;

2017

2018

2019

2020

2021

2022

2023

2024

2025

2026









&#160;
</oef:LineGraphTableTextBlock>
    <oef:LineGraphAndTableMeasureName contextRef="C000182864_LG_ClassMember_10YR" id="ixv-252">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity&#xae; Total Bond K6 Fund&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000182864_ClassMember_AsOf_2017"
      decimals="0"
      id="ixv-306929"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000182864_ClassMember_AsOf_2018"
      decimals="0"
      id="ixv-306930"
      unitRef="usd">10135</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000182864_ClassMember_AsOf_2019"
      decimals="0"
      id="ixv-306931"
      unitRef="usd">10068</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000182864_ClassMember_AsOf_2020"
      decimals="0"
      id="ixv-306932"
      unitRef="usd">11046</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000182864_ClassMember_AsOf_2021"
      decimals="0"
      id="ixv-306933"
      unitRef="usd">11905</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000182864_ClassMember_AsOf_2022"
      decimals="0"
      id="ixv-306934"
      unitRef="usd">12206</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000182864_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-306935"
      unitRef="usd">10854</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000182864_ClassMember_AsOf_2024"
      decimals="0"
      id="ixv-306936"
      unitRef="usd">10882</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000182864_ClassMember_AsOf_2025"
      decimals="0"
      id="ixv-306937"
      unitRef="usd">11779</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000182864_ClassMember_AsOf_2026"
      decimals="0"
      id="ixv-306938"
      unitRef="usd">12235</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000182864_LG_1_AdditionalIndexMember_10YR"
      id="ixv-297">&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="C000182864_1_AdditionalIndexMember_AsOf_2017"
      decimals="0"
      id="ixv-306939"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000182864_1_AdditionalIndexMember_AsOf_2018"
      decimals="0"
      id="ixv-306940"
      unitRef="usd">10154</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000182864_1_AdditionalIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-306941"
      unitRef="usd">10047</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000182864_1_AdditionalIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-306942"
      unitRef="usd">11070</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000182864_1_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-306943"
      unitRef="usd">11786</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000182864_1_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-306944"
      unitRef="usd">11776</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000182864_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-306945"
      unitRef="usd">10420</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000182864_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-306946"
      unitRef="usd">10296</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000182864_1_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-306947"
      unitRef="usd">11047</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000182864_1_AdditionalIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-306948"
      unitRef="usd">11393</oef:AccmVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000182864_ClassMember" id="ixv-391">AVERAGE ANNUAL TOTAL RETURNS:

&#160;

1 Year

5 Year

Life of Fund&#160;A


Fidelity&#xae; Total Bond K6 Fund

2.19%

0.48%

2.44%


Bloomberg U.S. Aggregate Bond Index

1.89%


-0.29%


1.62%




A&#160; &#160;From May 25, 2017

&#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
      contextRef="C000182864_NoLoadClassMember_1YR"
      decimals="INF"
      id="ixv-306949"
      unitRef="pure">0.0219</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000182864_NoLoadClassMember_5YR"
      decimals="INF"
      id="ixv-306950"
      unitRef="pure">0.0048</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000182864_NoLoadClassMember_2025-09-01_2026-08-31"
      decimals="INF"
      id="ixv-306951"
      unitRef="pure">0.0244</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000182864_0_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-306952"
      unitRef="pure">0.0189</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000182864_0_BBIndexMember_5YR"
      decimals="INF"
      id="ixv-306953"
      unitRef="pure">-0.0029</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000182864_0_BBIndexMember_LOC"
      decimals="INF"
      id="ixv-306954"
      unitRef="pure">0.0162</oef:AvgAnnlRtrPct>
    <oef:PerfInceptionDate
      contextRef="C000182864_Perf_2017-05-25_ClassMember"
      id="ixv-446">2017-05-25</oef:PerfInceptionDate>
    <oef:UpdPerfInfoLocationTextBlock contextRef="C000182864_ClassMember" id="ixv-456">&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="C000182864_ClassMember" id="ixv-468">&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="C000182864_ClassMember" id="ixv-472">&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="C000182864_ClassMember" id="ixv-478">&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;$&lt;/span&gt;7,886,764,107&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;4,698&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;23,059,841&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;159&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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&#160;
U.S. Government and U.S. Government Agency Obligations

55.9


AAA

6.5


AA

0.4


A

6.9


BBB

13.8


BB

3.9


B

5.1


CCC,CC,C

1.0


D

0.0


Not Rated

8.4


Equities

0.1




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

U.S. Government and U.S. Government Agency Obligations - 55.9


&#160;

AAA - 6.5&#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 - 0.4&#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 - 6.9&#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;


&#160;

BBB - 13.8&#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;

BB - 3.9&#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 - 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;&#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 - 8.4&#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;

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) - (2.0)% 


&#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

39.9


Corporate Bonds

23.2


U.S. Government Agency - Mortgage Securities

16.0


Asset-Backed Securities

8.7


CMOs and Other Mortgage Related Securities

7.7


Bank Loan Obligations

5.0


Foreign Government and Government Agency Obligations

1.1


Preferred Securities

0.2


Common Stocks

0.1


Alternative Funds

0.1


Preferred Stocks

0.0


Other Investments

0.0


Options

0.0




ASSET ALLOCATION (% of Fund's net assets)


&#160;



&#160;

U.S. Treasury Obligations - 39.9&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Corporate Bonds - 23.2&#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 - 16.0


&#160;

Asset-Backed Securities - 8.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

CMOs and Other Mortgage Related Securities - 7.7


&#160;

Bank Loan Obligations - 5.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Foreign Government and Government Agency Obligations - 1.1


&#160;

Preferred Securities - 0.2&#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;

Alternative Funds - 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;

Other Investments - 0.0&#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) - (2.0)%


&#160;






United States

87.8


Grand Cayman (UK Overseas Ter)

4.2


United Kingdom

1.1


Mexico

1.1


Bailiwick Of Jersey

0.9


Ireland

0.8


Germany

0.7


Canada

0.6


Switzerland

0.5


Others

2.3




GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

United States - 87.8&#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) - 4.2&#160;&#160;&#160;&#160;


&#160;

United Kingdom - 1.1&#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 - 0.9&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Ireland - 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;

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;

Canada - 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;

Switzerland - 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;

Others - 2.3&#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-306976"
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    <oef:PctOfNav
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      id="ixv-306977"
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      decimals="INF"
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    <oef:PctOfNav
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      decimals="INF"
      id="ixv-306979"
      unitRef="pure">0.001</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-306980"
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    <oef:PctOfNav
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      decimals="INF"
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      unitRef="pure">0.000</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
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    <oef:PctOfNav
      contextRef="C000182864_GD_US_Member"
      decimals="INF"
      id="ixv-306983"
      unitRef="pure">0.878</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-306984"
      unitRef="pure">0.042</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000182864_GD_GB_Member"
      decimals="INF"
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      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
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      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000182864_GD_BailiwickOfJersey_Member"
      decimals="INF"
      id="ixv-306987"
      unitRef="pure">0.009</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000182864_GD_IE_Member"
      decimals="INF"
      id="ixv-306988"
      unitRef="pure">0.008</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000182864_GD_DE_Member"
      decimals="INF"
      id="ixv-306989"
      unitRef="pure">0.007</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000182864_GD_CA_Member"
      decimals="INF"
      id="ixv-306990"
      unitRef="pure">0.006</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000182864_GD_CH_Member"
      decimals="INF"
      id="ixv-306991"
      unitRef="pure">0.005</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-306992"
      unitRef="pure">0.023</oef:PctOfNav>
    <oef:LargestHoldingsTableTextBlock contextRef="C000182864_ClassMember" id="ixv-1104">TOP HOLDINGS(% of Fund's net assets)

&#160;

&#160;


US Treasury Notes

27.6


&#160;


US Treasury Bonds

12.3


&#160;


Fannie Mae Mortgage pass-thru certificates

5.4


&#160;


Ginnie Mae II Pool

3.4


&#160;


Freddie Mac Gold Pool

3.2


&#160;


Uniform Mortgage Backed Securities

2.7


&#160;


Freddie Mac Multifamily Structured pass-thru certificates

1.5


&#160;


JPMorgan Chase &amp; Co

1.3


&#160;


Ginnie Mae I Pool

0.9


&#160;


Wells Fargo &amp; Co

0.9


&#160;


&#160;

59.2

&#160;



</oef:LargestHoldingsTableTextBlock>
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      contextRef="C000182864_TH_0_Member"
      decimals="INF"
      id="ixv-306993"
      unitRef="pure">0.276</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000182864_TH_1_Member"
      decimals="INF"
      id="ixv-306994"
      unitRef="pure">0.123</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000182864_TH_2_Member"
      decimals="INF"
      id="ixv-306995"
      unitRef="pure">0.054</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000182864_TH_3_Member"
      decimals="INF"
      id="ixv-306996"
      unitRef="pure">0.034</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000182864_TH_4_Member"
      decimals="INF"
      id="ixv-306997"
      unitRef="pure">0.032</oef:PctOfNav>
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      decimals="INF"
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      unitRef="pure">0.027</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-306999"
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    <oef:PctOfNav
      contextRef="C000182864_TH_7_Member"
      decimals="INF"
      id="ixv-307000"
      unitRef="pure">0.013</oef:PctOfNav>
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      decimals="INF"
      id="ixv-307001"
      unitRef="pure">0.009</oef:PctOfNav>
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      decimals="INF"
      id="ixv-307002"
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    <oef:MaterialFundChngTextBlock contextRef="C000182864_ClassMember" id="ixv-1229">
&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;1-800-835-5092&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="C000182864_ClassMember" id="ixv-1235">&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;1-800-835-5092&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="C000182864_ClassMember" id="ixv-1237">&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="C000182864_ClassMember" id="ixv-1240">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;1-800-835-5092&lt;/span&gt;</oef:UpdProspectusPhoneNumber>
    <oef:UpdProspectusEmailAddress contextRef="C000182864_ClassMember" id="ixv-1244">&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="C000182864_ClassMember" id="ixv-1255">
&lt;div style="text-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-1313">2026-08-31</dei:DocumentPeriodEndDate>
    <oef:MaterialFundChngNoticeTextBlock contextRef="C000019272_ClassMember" id="ixv-1317">This report describes changes to the Fund that occurred during the reporting period.</oef:MaterialFundChngNoticeTextBlock>
    <oef:FundName contextRef="C000019272_ClassMember" id="ixv-1328">Fidelity&#xae; Total Bond Fund</oef:FundName>
    <oef:ClassName contextRef="C000019272_ClassMember" id="ixv-1331">Fidelity&#xae; Total Bond Fund</oef:ClassName>
    <dei:TradingSymbol contextRef="C000019272_ClassMember" id="ixv-1335">FTBFX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000019272_ClassMember" id="ixv-1354">This annual shareholder report contains information about Fidelity&#xae; Total Bond Fund for the period September 1, 2025 to August 31, 2026.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000019272_ClassMember" id="ixv-1356">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000019272_ClassMember" id="ixv-1361">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="C000019272_ClassMember" id="ixv-1363">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000019272_ClassMember" id="ixv-1366">1-800-544-8544</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000019272_ClassMember" id="ixv-1369">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000019272_ClassMember" id="ixv-1376">&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 $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:51%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity&#xae; Total Bond Fund&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:21%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&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;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="C000019272_ClassMember"
      decimals="0"
      id="ixv-307003"
      unitRef="usd">45</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000019272_ClassMember"
      decimals="INF"
      id="ixv-307004"
      unitRef="pure">0.0045</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000019272_ClassMember" id="ixv-1419">&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 Bond 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="C000019272_ClassMember" id="ixv-1446">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; Total Bond Fund


$10,000

$10,207


$10,151


$11,131


$11,979


$12,265


$10,865


$10,904


$11,834


$12,283


$12,530



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="C000019272_LG_ClassMember_11YR" id="ixv-1465">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity&#xae; Total Bond Fund&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000019272_ClassMember_AsOf_2016"
      decimals="0"
      id="ixv-307005"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019272_ClassMember_AsOf_2017"
      decimals="0"
      id="ixv-307006"
      unitRef="usd">10207</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019272_ClassMember_AsOf_2018"
      decimals="0"
      id="ixv-307007"
      unitRef="usd">10151</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019272_ClassMember_AsOf_2019"
      decimals="0"
      id="ixv-307008"
      unitRef="usd">11131</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019272_ClassMember_AsOf_2020"
      decimals="0"
      id="ixv-307009"
      unitRef="usd">11979</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019272_ClassMember_AsOf_2021"
      decimals="0"
      id="ixv-307010"
      unitRef="usd">12265</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019272_ClassMember_AsOf_2022"
      decimals="0"
      id="ixv-307011"
      unitRef="usd">10865</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019272_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-307012"
      unitRef="usd">10904</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019272_ClassMember_AsOf_2024"
      decimals="0"
      id="ixv-307013"
      unitRef="usd">11834</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019272_ClassMember_AsOf_2025"
      decimals="0"
      id="ixv-307014"
      unitRef="usd">12283</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019272_ClassMember_AsOf_2026"
      decimals="0"
      id="ixv-307015"
      unitRef="usd">12530</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000019272_LG_1_AdditionalIndexMember_11YR"
      id="ixv-1514">&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="C000019272_1_AdditionalIndexMember_AsOf_2016"
      decimals="0"
      id="ixv-307016"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019272_1_AdditionalIndexMember_AsOf_2017"
      decimals="0"
      id="ixv-307017"
      unitRef="usd">10049</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019272_1_AdditionalIndexMember_AsOf_2018"
      decimals="0"
      id="ixv-307018"
      unitRef="usd">9944</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019272_1_AdditionalIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-307019"
      unitRef="usd">10955</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019272_1_AdditionalIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-307020"
      unitRef="usd">11665</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019272_1_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-307021"
      unitRef="usd">11655</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019272_1_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-307022"
      unitRef="usd">10313</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019272_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-307023"
      unitRef="usd">10189</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019272_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-307024"
      unitRef="usd">10933</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019272_1_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-307025"
      unitRef="usd">11276</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019272_1_AdditionalIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-307026"
      unitRef="usd">11489</oef:AccmVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000019272_ClassMember" id="ixv-1615">AVERAGE ANNUAL TOTAL RETURNS:

&#160;

1 Year

5 Year

10 Year


Fidelity&#xae; Total Bond Fund

2.01%

0.43%

2.28%


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="C000019272_NoLoadClassMember_1YR"
      decimals="INF"
      id="ixv-307027"
      unitRef="pure">0.0201</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019272_NoLoadClassMember_5YR"
      decimals="INF"
      id="ixv-307028"
      unitRef="pure">0.0043</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019272_NoLoadClassMember_10YR"
      decimals="INF"
      id="ixv-307029"
      unitRef="pure">0.0228</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019272_0_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-307030"
      unitRef="pure">0.0189</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019272_0_BBIndexMember_5YR"
      decimals="INF"
      id="ixv-307031"
      unitRef="pure">-0.0029</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019272_0_BBIndexMember_10YR"
      decimals="INF"
      id="ixv-307032"
      unitRef="pure">0.0140</oef:AvgAnnlRtrPct>
    <oef:UpdPerfInfoLocationTextBlock contextRef="C000019272_ClassMember" id="ixv-1671">&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="C000019272_ClassMember" id="ixv-1683">&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="C000019272_ClassMember" id="ixv-1687">&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="C000019272_ClassMember" id="ixv-1693">&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;$&lt;/span&gt;41,945,078,703&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;6,727&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;118,864,423&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;152&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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    <oef:HoldingsTableTextBlock contextRef="C000019272_ClassMember" id="ixv-1768">
&#160;
U.S. Government and U.S. Government Agency Obligations

55.4


AAA

5.5


AA

0.7


A

7.8


BBB

13.6


BB

4.1


B

5.1


CCC,CC,C

1.1


D

0.0


Not Rated

8.8


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 - 5.5&#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 - 0.7&#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 - 7.8&#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 - 13.6&#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 - 4.1&#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;

B - 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;&#160;&#160;


&#160;

CCC,CC,C - 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;

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 - 8.8&#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;

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) - (2.2)% 


&#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

39.4


Corporate Bonds

23.3


U.S. Government Agency - Mortgage Securities

16.0


Asset-Backed Securities

8.5


CMOs and Other Mortgage Related Securities

7.8


Bank Loan Obligations

5.3


Foreign Government and Government Agency Obligations

1.4


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 - 39.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Corporate Bonds - 23.3&#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 - 16.0


&#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 - 5.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Foreign Government and Government Agency Obligations - 1.4


&#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) - (2.2)%


&#160;






United States

87.3


Grand Cayman (UK Overseas Ter)

4.5


United Kingdom

1.1


Mexico

1.1


Bailiwick Of Jersey

0.6


Ireland

0.6


Germany

0.6


Switzerland

0.5


France

0.5


Others

3.2




GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

United States - 87.3&#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) - 4.5&#160;&#160;&#160;&#160;


&#160;

United Kingdom - 1.1&#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 - 0.6&#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;

Germany - 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;

Switzerland - 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;

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;

Others - 3.2&#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;
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    <oef:LargestHoldingsTableTextBlock contextRef="C000019272_ClassMember" id="ixv-2302">TOP HOLDINGS(% of Fund's net assets)

&#160;

&#160;


US Treasury Notes

27.4


&#160;


US Treasury Bonds

12.0


&#160;


Fannie Mae Mortgage pass-thru certificates

5.0


&#160;


Freddie Mac Gold Pool

3.9


&#160;


Ginnie Mae II Pool

3.4


&#160;


Uniform Mortgage Backed Securities

2.7


&#160;


Freddie Mac Multifamily Structured pass-thru certificates

1.6


&#160;


JPMorgan Chase &amp; Co

1.3


&#160;


Morgan Stanley

1.1


&#160;


Bank of America Corp

1.0


&#160;


&#160;

59.4

&#160;



</oef:LargestHoldingsTableTextBlock>
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      id="ixv-307077"
      unitRef="pure">0.013</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019272_TH_8_Member"
      decimals="INF"
      id="ixv-307078"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019272_TH_9_Member"
      decimals="INF"
      id="ixv-307079"
      unitRef="pure">0.010</oef:PctOfNav>
    <oef:MaterialFundChngTextBlock contextRef="C000019272_ClassMember" id="ixv-2427">
&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 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="C000019272_ClassMember" id="ixv-2433">&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="C000019272_ClassMember" id="ixv-2435">&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="C000019272_ClassMember" id="ixv-2438">&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="C000019272_ClassMember" id="ixv-2442">&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="C000019272_ClassMember" id="ixv-2453">
&lt;div style="text-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-2511">2026-08-31</dei:DocumentPeriodEndDate>
    <oef:MaterialFundChngNoticeTextBlock contextRef="C000150510_ClassMember" id="ixv-2515">This report describes changes to the Fund that occurred during the reporting period.</oef:MaterialFundChngNoticeTextBlock>
    <oef:FundName contextRef="C000150510_ClassMember" id="ixv-2526">Fidelity&#xae; Total Bond Fund</oef:FundName>
    <oef:ClassName contextRef="C000150510_ClassMember" id="ixv-2529">Fidelity Advisor&#xae; Total Bond Fund Class Z</oef:ClassName>
    <dei:TradingSymbol contextRef="C000150510_ClassMember" id="ixv-2533">FBKWX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000150510_ClassMember" id="ixv-2552">This annual shareholder report contains information about Fidelity&#xae; Total Bond Fund for the period September 1, 2025 to August 31, 2026.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000150510_ClassMember" id="ixv-2554">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000150510_ClassMember" id="ixv-2559">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="C000150510_ClassMember" id="ixv-2561">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000150510_ClassMember" id="ixv-2564">1-877-208-0098</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000150510_ClassMember" id="ixv-2567">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000150510_ClassMember" id="ixv-2574">&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="C000150510_ClassMember"
      decimals="0"
      id="ixv-307080"
      unitRef="usd">36</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000150510_ClassMember"
      decimals="INF"
      id="ixv-307081"
      unitRef="pure">0.0036</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000150510_ClassMember" id="ixv-2617">&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 Bond 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="C000150510_ClassMember" id="ixv-2644">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 Z


$10,000

$10,216


$10,159


$11,150


$12,012


$12,310


$10,922


$10,971


$11,905


$12,381


$12,641



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="C000150510_LG_ClassMember_11YR" id="ixv-2663">&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="C000150510_ClassMember_AsOf_2016"
      decimals="0"
      id="ixv-307082"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000150510_ClassMember_AsOf_2017"
      decimals="0"
      id="ixv-307083"
      unitRef="usd">10216</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000150510_ClassMember_AsOf_2018"
      decimals="0"
      id="ixv-307084"
      unitRef="usd">10159</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000150510_ClassMember_AsOf_2019"
      decimals="0"
      id="ixv-307085"
      unitRef="usd">11150</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000150510_ClassMember_AsOf_2020"
      decimals="0"
      id="ixv-307086"
      unitRef="usd">12012</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000150510_ClassMember_AsOf_2021"
      decimals="0"
      id="ixv-307087"
      unitRef="usd">12310</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000150510_ClassMember_AsOf_2022"
      decimals="0"
      id="ixv-307088"
      unitRef="usd">10922</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000150510_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-307089"
      unitRef="usd">10971</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000150510_ClassMember_AsOf_2024"
      decimals="0"
      id="ixv-307090"
      unitRef="usd">11905</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000150510_ClassMember_AsOf_2025"
      decimals="0"
      id="ixv-307091"
      unitRef="usd">12381</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000150510_ClassMember_AsOf_2026"
      decimals="0"
      id="ixv-307092"
      unitRef="usd">12641</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000150510_LG_1_AdditionalIndexMember_11YR"
      id="ixv-2712">&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="C000150510_1_AdditionalIndexMember_AsOf_2016"
      decimals="0"
      id="ixv-307093"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000150510_1_AdditionalIndexMember_AsOf_2017"
      decimals="0"
      id="ixv-307094"
      unitRef="usd">10049</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000150510_1_AdditionalIndexMember_AsOf_2018"
      decimals="0"
      id="ixv-307095"
      unitRef="usd">9944</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000150510_1_AdditionalIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-307096"
      unitRef="usd">10955</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000150510_1_AdditionalIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-307097"
      unitRef="usd">11665</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000150510_1_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-307098"
      unitRef="usd">11655</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000150510_1_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-307099"
      unitRef="usd">10313</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000150510_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-307100"
      unitRef="usd">10189</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000150510_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-307101"
      unitRef="usd">10933</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000150510_1_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-307102"
      unitRef="usd">11276</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000150510_1_AdditionalIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-307103"
      unitRef="usd">11489</oef:AccmVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000150510_ClassMember" id="ixv-2813">AVERAGE ANNUAL TOTAL RETURNS:

&#160;

1 Year

5 Year

10 Year


Class Z

2.10%

0.53%

2.37%


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="C000150510_NoLoadClassMember_1YR"
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      id="ixv-307104"
      unitRef="pure">0.0210</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000150510_NoLoadClassMember_5YR"
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      id="ixv-307105"
      unitRef="pure">0.0053</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000150510_NoLoadClassMember_10YR"
      decimals="INF"
      id="ixv-307106"
      unitRef="pure">0.0237</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000150510_0_BBIndexMember_1YR"
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      id="ixv-307107"
      unitRef="pure">0.0189</oef:AvgAnnlRtrPct>
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      id="ixv-307108"
      unitRef="pure">-0.0029</oef:AvgAnnlRtrPct>
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      contextRef="C000150510_0_BBIndexMember_10YR"
      decimals="INF"
      id="ixv-307109"
      unitRef="pure">0.0140</oef:AvgAnnlRtrPct>
    <oef:UpdPerfInfoLocationTextBlock contextRef="C000150510_ClassMember" id="ixv-2869">&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="C000150510_ClassMember" id="ixv-2881">&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="C000150510_ClassMember" id="ixv-2885">&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="C000150510_ClassMember" id="ixv-2891">&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;$&lt;/span&gt;41,945,078,703&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;6,727&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;118,864,423&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;152&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">41945078703</us-gaap:AssetsNet>
    <oef:HoldingsCount
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      decimals="0"
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      unitRef="usd">118864423</oef:AdvisoryFeesPaidAmt>
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    <oef:HoldingsTableTextBlock contextRef="C000150510_ClassMember" id="ixv-2966">
&#160;
U.S. Government and U.S. Government Agency Obligations

55.4


AAA

5.5


AA

0.7


A

7.8


BBB

13.6


BB

4.1


B

5.1


CCC,CC,C

1.1


D

0.0


Not Rated

8.8


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 - 5.5&#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 - 0.7&#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 - 7.8&#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 - 13.6&#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 - 4.1&#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;

B - 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;&#160;&#160;


&#160;

CCC,CC,C - 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;

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 - 8.8&#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;

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) - (2.2)% 


&#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

39.4


Corporate Bonds

23.3


U.S. Government Agency - Mortgage Securities

16.0


Asset-Backed Securities

8.5


CMOs and Other Mortgage Related Securities

7.8


Bank Loan Obligations

5.3


Foreign Government and Government Agency Obligations

1.4


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 - 39.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Corporate Bonds - 23.3&#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 - 16.0


&#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 - 5.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Foreign Government and Government Agency Obligations - 1.4


&#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) - (2.2)%


&#160;






United States

87.3


Grand Cayman (UK Overseas Ter)

4.5


United Kingdom

1.1


Mexico

1.1


Bailiwick Of Jersey

0.6


Ireland

0.6


Germany

0.6


Switzerland

0.5


France

0.5


Others

3.2




GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

United States - 87.3&#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) - 4.5&#160;&#160;&#160;&#160;


&#160;

United Kingdom - 1.1&#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 - 0.6&#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;

Germany - 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;

Switzerland - 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;

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;

Others - 3.2&#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;
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      unitRef="pure">0.006</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000150510_GD_IE_Member"
      decimals="INF"
      id="ixv-307142"
      unitRef="pure">0.006</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000150510_GD_DE_Member"
      decimals="INF"
      id="ixv-307143"
      unitRef="pure">0.006</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000150510_GD_CH_Member"
      decimals="INF"
      id="ixv-307144"
      unitRef="pure">0.005</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000150510_GD_FR_Member"
      decimals="INF"
      id="ixv-307145"
      unitRef="pure">0.005</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000150510_GD_Other_Member"
      decimals="INF"
      id="ixv-307146"
      unitRef="pure">0.032</oef:PctOfNav>
    <oef:LargestHoldingsTableTextBlock contextRef="C000150510_ClassMember" id="ixv-3500">TOP HOLDINGS(% of Fund's net assets)

&#160;

&#160;


US Treasury Notes

27.4


&#160;


US Treasury Bonds

12.0


&#160;


Fannie Mae Mortgage pass-thru certificates

5.0


&#160;


Freddie Mac Gold Pool

3.9


&#160;


Ginnie Mae II Pool

3.4


&#160;


Uniform Mortgage Backed Securities

2.7


&#160;


Freddie Mac Multifamily Structured pass-thru certificates

1.6


&#160;


JPMorgan Chase &amp; Co

1.3


&#160;


Morgan Stanley

1.1


&#160;


Bank of America Corp

1.0


&#160;


&#160;

59.4

&#160;



</oef:LargestHoldingsTableTextBlock>
    <oef:PctOfNav
      contextRef="C000150510_TH_0_Member"
      decimals="INF"
      id="ixv-307147"
      unitRef="pure">0.274</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000150510_TH_1_Member"
      decimals="INF"
      id="ixv-307148"
      unitRef="pure">0.120</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000150510_TH_2_Member"
      decimals="INF"
      id="ixv-307149"
      unitRef="pure">0.050</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000150510_TH_3_Member"
      decimals="INF"
      id="ixv-307150"
      unitRef="pure">0.039</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000150510_TH_4_Member"
      decimals="INF"
      id="ixv-307151"
      unitRef="pure">0.034</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000150510_TH_5_Member"
      decimals="INF"
      id="ixv-307152"
      unitRef="pure">0.027</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000150510_TH_6_Member"
      decimals="INF"
      id="ixv-307153"
      unitRef="pure">0.016</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000150510_TH_7_Member"
      decimals="INF"
      id="ixv-307154"
      unitRef="pure">0.013</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000150510_TH_8_Member"
      decimals="INF"
      id="ixv-307155"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000150510_TH_9_Member"
      decimals="INF"
      id="ixv-307156"
      unitRef="pure">0.010</oef:PctOfNav>
    <oef:MaterialFundChngTextBlock contextRef="C000150510_ClassMember" id="ixv-3625">
&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 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="C000150510_ClassMember" id="ixv-3631">&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="C000150510_ClassMember" id="ixv-3633">&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="C000150510_ClassMember" id="ixv-3636">&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="C000150510_ClassMember" id="ixv-3640">&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="C000150510_ClassMember" id="ixv-3651">
&lt;div style="text-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-3709">2026-08-31</dei:DocumentPeriodEndDate>
    <oef:MaterialFundChngNoticeTextBlock contextRef="C000019276_ClassMember" id="ixv-3713">This report describes changes to the Fund that occurred during the reporting period.</oef:MaterialFundChngNoticeTextBlock>
    <oef:FundName contextRef="C000019276_ClassMember" id="ixv-3724">Fidelity&#xae; Total Bond Fund</oef:FundName>
    <oef:ClassName contextRef="C000019276_ClassMember" id="ixv-3727">Fidelity Advisor&#xae; Total Bond Fund Class M</oef:ClassName>
    <dei:TradingSymbol contextRef="C000019276_ClassMember" id="ixv-3731">FEPTX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000019276_ClassMember" id="ixv-3750">This annual shareholder report contains information about Fidelity&#xae; Total Bond Fund for the period September 1, 2025 to August 31, 2026.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000019276_ClassMember" id="ixv-3752">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000019276_ClassMember" id="ixv-3757">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="C000019276_ClassMember" id="ixv-3759">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000019276_ClassMember" id="ixv-3762">1-877-208-0098</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000019276_ClassMember" id="ixv-3765">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000019276_ClassMember" id="ixv-3772">&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;0.74&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="C000019276_ClassMember"
      decimals="0"
      id="ixv-307157"
      unitRef="usd">75</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000019276_ClassMember"
      decimals="INF"
      id="ixv-307158"
      unitRef="pure">0.0074</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000019276_ClassMember" id="ixv-3815">&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 Bond 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="C000019276_ClassMember" id="ixv-3842">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

$9,769


$9,675


$10,578


$11,352


$11,588


$10,242


$10,248


$11,078


$11,477


$11,673



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="C000019276_LG_ClassMember_11YR" id="ixv-3863">&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="C000019276_ClassMember_AsOf_2016"
      decimals="0"
      id="ixv-307159"
      unitRef="usd">9600</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019276_ClassMember_AsOf_2017"
      decimals="0"
      id="ixv-307160"
      unitRef="usd">9769</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019276_ClassMember_AsOf_2018"
      decimals="0"
      id="ixv-307161"
      unitRef="usd">9675</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019276_ClassMember_AsOf_2019"
      decimals="0"
      id="ixv-307162"
      unitRef="usd">10578</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019276_ClassMember_AsOf_2020"
      decimals="0"
      id="ixv-307163"
      unitRef="usd">11352</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019276_ClassMember_AsOf_2021"
      decimals="0"
      id="ixv-307164"
      unitRef="usd">11588</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019276_ClassMember_AsOf_2022"
      decimals="0"
      id="ixv-307165"
      unitRef="usd">10242</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019276_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-307166"
      unitRef="usd">10248</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019276_ClassMember_AsOf_2024"
      decimals="0"
      id="ixv-307167"
      unitRef="usd">11078</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019276_ClassMember_AsOf_2025"
      decimals="0"
      id="ixv-307168"
      unitRef="usd">11477</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019276_ClassMember_AsOf_2026"
      decimals="0"
      id="ixv-307169"
      unitRef="usd">11673</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000019276_LG_1_AdditionalIndexMember_11YR"
      id="ixv-3912">&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="C000019276_1_AdditionalIndexMember_AsOf_2016"
      decimals="0"
      id="ixv-307170"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019276_1_AdditionalIndexMember_AsOf_2017"
      decimals="0"
      id="ixv-307171"
      unitRef="usd">10049</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019276_1_AdditionalIndexMember_AsOf_2018"
      decimals="0"
      id="ixv-307172"
      unitRef="usd">9944</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019276_1_AdditionalIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-307173"
      unitRef="usd">10955</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019276_1_AdditionalIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-307174"
      unitRef="usd">11665</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019276_1_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-307175"
      unitRef="usd">11655</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019276_1_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-307176"
      unitRef="usd">10313</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019276_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-307177"
      unitRef="usd">10189</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019276_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-307178"
      unitRef="usd">10933</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019276_1_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-307179"
      unitRef="usd">11276</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019276_1_AdditionalIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-307180"
      unitRef="usd">11489</oef:AccmVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000019276_ClassMember" id="ixv-4013">AVERAGE ANNUAL TOTAL RETURNS:

&#160;

1 Year

5 Year

10 Year


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

-2.36%

-0.67%


1.56%


Class M (without 4.00% sales charge)

1.71%

0.15%

1.97%


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="C000019276_ClassMember_1YR"
      decimals="INF"
      id="ixv-307181"
      unitRef="pure">-0.0236</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019276_ClassMember_5YR"
      decimals="INF"
      id="ixv-307182"
      unitRef="pure">-0.0067</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019276_ClassMember_10YR"
      decimals="INF"
      id="ixv-307183"
      unitRef="pure">0.0156</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019276_NoLoadClassMember_1YR"
      decimals="INF"
      id="ixv-307184"
      unitRef="pure">0.0171</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019276_NoLoadClassMember_5YR"
      decimals="INF"
      id="ixv-307185"
      unitRef="pure">0.0015</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019276_NoLoadClassMember_10YR"
      decimals="INF"
      id="ixv-307186"
      unitRef="pure">0.0197</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019276_0_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-307187"
      unitRef="pure">0.0189</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019276_0_BBIndexMember_5YR"
      decimals="INF"
      id="ixv-307188"
      unitRef="pure">-0.0029</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019276_0_BBIndexMember_10YR"
      decimals="INF"
      id="ixv-307189"
      unitRef="pure">0.0140</oef:AvgAnnlRtrPct>
    <oef:UpdPerfInfoLocationTextBlock contextRef="C000019276_ClassMember" id="ixv-4086">&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="C000019276_ClassMember" id="ixv-4098">&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="C000019276_ClassMember" id="ixv-4102">&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="C000019276_ClassMember" id="ixv-4108">&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;$&lt;/span&gt;41,945,078,703&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;6,727&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;118,864,423&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;152&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="C000019276_InstantMember"
      decimals="0"
      id="ixv-307190"
      unitRef="usd">41945078703</us-gaap:AssetsNet>
    <oef:HoldingsCount
      contextRef="C000019276_InstantMember"
      decimals="INF"
      id="ixv-307191"
      unitRef="holding">6727</oef:HoldingsCount>
    <oef:AdvisoryFeesPaidAmt
      contextRef="C000019276_ClassMember"
      decimals="0"
      id="ixv-307192"
      unitRef="usd">118864423</oef:AdvisoryFeesPaidAmt>
    <us-gaap:InvestmentCompanyPortfolioTurnover
      contextRef="C000019276_ClassMember"
      decimals="INF"
      id="ixv-307193"
      unitRef="pure">1.52</us-gaap:InvestmentCompanyPortfolioTurnover>
    <oef:HoldingsTableTextBlock contextRef="C000019276_ClassMember" id="ixv-4183">
&#160;
U.S. Government and U.S. Government Agency Obligations

55.4


AAA

5.5


AA

0.7


A

7.8


BBB

13.6


BB

4.1


B

5.1


CCC,CC,C

1.1


D

0.0


Not Rated

8.8


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 - 5.5&#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 - 0.7&#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 - 7.8&#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 - 13.6&#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 - 4.1&#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;

B - 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;&#160;&#160;


&#160;

CCC,CC,C - 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;

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 - 8.8&#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;

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) - (2.2)% 


&#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

39.4


Corporate Bonds

23.3


U.S. Government Agency - Mortgage Securities

16.0


Asset-Backed Securities

8.5


CMOs and Other Mortgage Related Securities

7.8


Bank Loan Obligations

5.3


Foreign Government and Government Agency Obligations

1.4


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 - 39.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Corporate Bonds - 23.3&#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 - 16.0


&#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 - 5.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Foreign Government and Government Agency Obligations - 1.4


&#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) - (2.2)%


&#160;






United States

87.3


Grand Cayman (UK Overseas Ter)

4.5


United Kingdom

1.1


Mexico

1.1


Bailiwick Of Jersey

0.6


Ireland

0.6


Germany

0.6


Switzerland

0.5


France

0.5


Others

3.2




GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

United States - 87.3&#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) - 4.5&#160;&#160;&#160;&#160;


&#160;

United Kingdom - 1.1&#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 - 0.6&#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;

Germany - 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;

Switzerland - 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;

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;

Others - 3.2&#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="C000019276_QD_USGovernmentandUSGovernmentAgencyObligations_Member"
      decimals="INF"
      id="ixv-307194"
      unitRef="pure">0.554</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019276_QD_AAA_Member"
      decimals="INF"
      id="ixv-307195"
      unitRef="pure">0.055</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019276_QD_AA_Member"
      decimals="INF"
      id="ixv-307196"
      unitRef="pure">0.007</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019276_QD_A_Member"
      decimals="INF"
      id="ixv-307197"
      unitRef="pure">0.078</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019276_QD_BBB_Member"
      decimals="INF"
      id="ixv-307198"
      unitRef="pure">0.136</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019276_QD_BB_Member"
      decimals="INF"
      id="ixv-307199"
      unitRef="pure">0.041</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019276_QD_B_Member"
      decimals="INF"
      id="ixv-307200"
      unitRef="pure">0.051</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019276_QD_CCCCCC_Member"
      decimals="INF"
      id="ixv-307201"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019276_QD_D_Member"
      decimals="INF"
      id="ixv-307202"
      unitRef="pure">0.000</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019276_QD_NotRated_Member"
      decimals="INF"
      id="ixv-307203"
      unitRef="pure">0.088</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019276_QD_Equities_Member"
      decimals="INF"
      id="ixv-307204"
      unitRef="pure">0.001</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019276_AA_USTreasuryObligations_Member"
      decimals="INF"
      id="ixv-307205"
      unitRef="pure">0.394</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019276_AA_CorporateBonds_Member"
      decimals="INF"
      id="ixv-307206"
      unitRef="pure">0.233</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019276_AA_USGovernmentAgencyMortgageSecurities_Member"
      decimals="INF"
      id="ixv-307207"
      unitRef="pure">0.160</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019276_AA_AssetBackedSecurities_Member"
      decimals="INF"
      id="ixv-307208"
      unitRef="pure">0.085</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019276_AA_CMOsandOtherMortgageRelatedSecurities_Member"
      decimals="INF"
      id="ixv-307209"
      unitRef="pure">0.078</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019276_AA_BankLoanObligations_Member"
      decimals="INF"
      id="ixv-307210"
      unitRef="pure">0.053</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019276_AA_ForeignGovernmentandGovernmentAgencyObligations_Member"
      decimals="INF"
      id="ixv-307211"
      unitRef="pure">0.014</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019276_AA_PreferredSecurities_Member"
      decimals="INF"
      id="ixv-307212"
      unitRef="pure">0.003</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019276_AA_CommonStocks_Member"
      decimals="INF"
      id="ixv-307213"
      unitRef="pure">0.001</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019276_AA_OtherInvestments_Member"
      decimals="INF"
      id="ixv-307214"
      unitRef="pure">0.001</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019276_AA_PreferredStocks_Member"
      decimals="INF"
      id="ixv-307215"
      unitRef="pure">0.000</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019276_AA_Options_Member"
      decimals="INF"
      id="ixv-307216"
      unitRef="pure">0.000</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019276_GD_US_Member"
      decimals="INF"
      id="ixv-307217"
      unitRef="pure">0.873</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019276_GD_GrandCaymanUKOverseasTer_Member"
      decimals="INF"
      id="ixv-307218"
      unitRef="pure">0.045</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019276_GD_GB_Member"
      decimals="INF"
      id="ixv-307219"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019276_GD_MX_Member"
      decimals="INF"
      id="ixv-307220"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019276_GD_BailiwickOfJersey_Member"
      decimals="INF"
      id="ixv-307221"
      unitRef="pure">0.006</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019276_GD_IE_Member"
      decimals="INF"
      id="ixv-307222"
      unitRef="pure">0.006</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-307223"
      unitRef="pure">0.006</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019276_GD_CH_Member"
      decimals="INF"
      id="ixv-307224"
      unitRef="pure">0.005</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019276_GD_FR_Member"
      decimals="INF"
      id="ixv-307225"
      unitRef="pure">0.005</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-307226"
      unitRef="pure">0.032</oef:PctOfNav>
    <oef:LargestHoldingsTableTextBlock contextRef="C000019276_ClassMember" id="ixv-4717">TOP HOLDINGS(% of Fund's net assets)

&#160;

&#160;


US Treasury Notes

27.4


&#160;


US Treasury Bonds

12.0


&#160;


Fannie Mae Mortgage pass-thru certificates

5.0


&#160;


Freddie Mac Gold Pool

3.9


&#160;


Ginnie Mae II Pool

3.4


&#160;


Uniform Mortgage Backed Securities

2.7


&#160;


Freddie Mac Multifamily Structured pass-thru certificates

1.6


&#160;


JPMorgan Chase &amp; Co

1.3


&#160;


Morgan Stanley

1.1


&#160;


Bank of America Corp

1.0


&#160;


&#160;

59.4

&#160;



</oef:LargestHoldingsTableTextBlock>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-307227"
      unitRef="pure">0.274</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019276_TH_1_Member"
      decimals="INF"
      id="ixv-307228"
      unitRef="pure">0.120</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019276_TH_2_Member"
      decimals="INF"
      id="ixv-307229"
      unitRef="pure">0.050</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019276_TH_3_Member"
      decimals="INF"
      id="ixv-307230"
      unitRef="pure">0.039</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019276_TH_4_Member"
      decimals="INF"
      id="ixv-307231"
      unitRef="pure">0.034</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019276_TH_5_Member"
      decimals="INF"
      id="ixv-307232"
      unitRef="pure">0.027</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019276_TH_6_Member"
      decimals="INF"
      id="ixv-307233"
      unitRef="pure">0.016</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019276_TH_7_Member"
      decimals="INF"
      id="ixv-307234"
      unitRef="pure">0.013</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019276_TH_8_Member"
      decimals="INF"
      id="ixv-307235"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019276_TH_9_Member"
      decimals="INF"
      id="ixv-307236"
      unitRef="pure">0.010</oef:PctOfNav>
    <oef:MaterialFundChngTextBlock contextRef="C000019276_ClassMember" id="ixv-4842">
&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 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="C000019276_ClassMember" id="ixv-4848">&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="C000019276_ClassMember" id="ixv-4850">&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="C000019276_ClassMember" id="ixv-4853">&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="C000019276_ClassMember" id="ixv-4857">&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="C000019276_ClassMember" id="ixv-4868">
&lt;div style="text-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-4926">2026-08-31</dei:DocumentPeriodEndDate>
    <oef:MaterialFundChngNoticeTextBlock contextRef="C000019277_ClassMember" id="ixv-4930">This report describes changes to the Fund that occurred during the reporting period.</oef:MaterialFundChngNoticeTextBlock>
    <oef:FundName contextRef="C000019277_ClassMember" id="ixv-4941">Fidelity&#xae; Total Bond Fund</oef:FundName>
    <oef:ClassName contextRef="C000019277_ClassMember" id="ixv-4944">Fidelity Advisor&#xae; Total Bond Fund Class I</oef:ClassName>
    <dei:TradingSymbol contextRef="C000019277_ClassMember" id="ixv-4948">FEPIX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000019277_ClassMember" id="ixv-4967">This annual shareholder report contains information about Fidelity&#xae; Total Bond Fund for the period September 1, 2025 to August 31, 2026.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000019277_ClassMember" id="ixv-4969">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000019277_ClassMember" id="ixv-4974">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="C000019277_ClassMember" id="ixv-4976">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000019277_ClassMember" id="ixv-4979">1-877-208-0098</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000019277_ClassMember" id="ixv-4982">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000019277_ClassMember" id="ixv-4989">&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="C000019277_ClassMember"
      decimals="0"
      id="ixv-307237"
      unitRef="usd">50</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000019277_ClassMember"
      decimals="INF"
      id="ixv-307238"
      unitRef="pure">0.0050</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000019277_ClassMember" id="ixv-5032">&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 Bond 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="C000019277_ClassMember" id="ixv-5059">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

$10,202


$10,131


$11,105


$11,946


$12,226


$10,832


$10,866


$11,775


$12,228


$12,468



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="C000019277_LG_ClassMember_11YR" id="ixv-5078">&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="C000019277_ClassMember_AsOf_2016"
      decimals="0"
      id="ixv-307239"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019277_ClassMember_AsOf_2017"
      decimals="0"
      id="ixv-307240"
      unitRef="usd">10202</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019277_ClassMember_AsOf_2018"
      decimals="0"
      id="ixv-307241"
      unitRef="usd">10131</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019277_ClassMember_AsOf_2019"
      decimals="0"
      id="ixv-307242"
      unitRef="usd">11105</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019277_ClassMember_AsOf_2020"
      decimals="0"
      id="ixv-307243"
      unitRef="usd">11946</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019277_ClassMember_AsOf_2021"
      decimals="0"
      id="ixv-307244"
      unitRef="usd">12226</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019277_ClassMember_AsOf_2022"
      decimals="0"
      id="ixv-307245"
      unitRef="usd">10832</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019277_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-307246"
      unitRef="usd">10866</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019277_ClassMember_AsOf_2024"
      decimals="0"
      id="ixv-307247"
      unitRef="usd">11775</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019277_ClassMember_AsOf_2025"
      decimals="0"
      id="ixv-307248"
      unitRef="usd">12228</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019277_ClassMember_AsOf_2026"
      decimals="0"
      id="ixv-307249"
      unitRef="usd">12468</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000019277_LG_1_AdditionalIndexMember_11YR"
      id="ixv-5127">&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="C000019277_1_AdditionalIndexMember_AsOf_2016"
      decimals="0"
      id="ixv-307250"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019277_1_AdditionalIndexMember_AsOf_2017"
      decimals="0"
      id="ixv-307251"
      unitRef="usd">10049</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019277_1_AdditionalIndexMember_AsOf_2018"
      decimals="0"
      id="ixv-307252"
      unitRef="usd">9944</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019277_1_AdditionalIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-307253"
      unitRef="usd">10955</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019277_1_AdditionalIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-307254"
      unitRef="usd">11665</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019277_1_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-307255"
      unitRef="usd">11655</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019277_1_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-307256"
      unitRef="usd">10313</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019277_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-307257"
      unitRef="usd">10189</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019277_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-307258"
      unitRef="usd">10933</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019277_1_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-307259"
      unitRef="usd">11276</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019277_1_AdditionalIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-307260"
      unitRef="usd">11489</oef:AccmVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000019277_ClassMember" id="ixv-5228">AVERAGE ANNUAL TOTAL RETURNS:

&#160;

1 Year

5 Year

10 Year


Class I

1.96%

0.39%

2.23%


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="C000019277_NoLoadClassMember_1YR"
      decimals="INF"
      id="ixv-307261"
      unitRef="pure">0.0196</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019277_NoLoadClassMember_5YR"
      decimals="INF"
      id="ixv-307262"
      unitRef="pure">0.0039</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019277_NoLoadClassMember_10YR"
      decimals="INF"
      id="ixv-307263"
      unitRef="pure">0.0223</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019277_0_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-307264"
      unitRef="pure">0.0189</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019277_0_BBIndexMember_5YR"
      decimals="INF"
      id="ixv-307265"
      unitRef="pure">-0.0029</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019277_0_BBIndexMember_10YR"
      decimals="INF"
      id="ixv-307266"
      unitRef="pure">0.0140</oef:AvgAnnlRtrPct>
    <oef:UpdPerfInfoLocationTextBlock contextRef="C000019277_ClassMember" id="ixv-5284">&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="C000019277_ClassMember" id="ixv-5296">&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="C000019277_ClassMember" id="ixv-5300">&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="C000019277_ClassMember" id="ixv-5306">&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;$&lt;/span&gt;41,945,078,703&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;6,727&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;118,864,423&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;152&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="C000019277_InstantMember"
      decimals="0"
      id="ixv-307267"
      unitRef="usd">41945078703</us-gaap:AssetsNet>
    <oef:HoldingsCount
      contextRef="C000019277_InstantMember"
      decimals="INF"
      id="ixv-307268"
      unitRef="holding">6727</oef:HoldingsCount>
    <oef:AdvisoryFeesPaidAmt
      contextRef="C000019277_ClassMember"
      decimals="0"
      id="ixv-307269"
      unitRef="usd">118864423</oef:AdvisoryFeesPaidAmt>
    <us-gaap:InvestmentCompanyPortfolioTurnover
      contextRef="C000019277_ClassMember"
      decimals="INF"
      id="ixv-307270"
      unitRef="pure">1.52</us-gaap:InvestmentCompanyPortfolioTurnover>
    <oef:HoldingsTableTextBlock contextRef="C000019277_ClassMember" id="ixv-5381">
&#160;
U.S. Government and U.S. Government Agency Obligations

55.4


AAA

5.5


AA

0.7


A

7.8


BBB

13.6


BB

4.1


B

5.1


CCC,CC,C

1.1


D

0.0


Not Rated

8.8


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 - 5.5&#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 - 0.7&#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 - 7.8&#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 - 13.6&#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 - 4.1&#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;

B - 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;&#160;&#160;


&#160;

CCC,CC,C - 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;

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 - 8.8&#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;

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) - (2.2)% 


&#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

39.4


Corporate Bonds

23.3


U.S. Government Agency - Mortgage Securities

16.0


Asset-Backed Securities

8.5


CMOs and Other Mortgage Related Securities

7.8


Bank Loan Obligations

5.3


Foreign Government and Government Agency Obligations

1.4


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 - 39.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Corporate Bonds - 23.3&#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 - 16.0


&#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 - 5.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Foreign Government and Government Agency Obligations - 1.4


&#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) - (2.2)%


&#160;






United States

87.3


Grand Cayman (UK Overseas Ter)

4.5


United Kingdom

1.1


Mexico

1.1


Bailiwick Of Jersey

0.6


Ireland

0.6


Germany

0.6


Switzerland

0.5


France

0.5


Others

3.2




GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

United States - 87.3&#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) - 4.5&#160;&#160;&#160;&#160;


&#160;

United Kingdom - 1.1&#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 - 0.6&#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;

Germany - 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;

Switzerland - 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;

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;

Others - 3.2&#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="C000019277_QD_USGovernmentandUSGovernmentAgencyObligations_Member"
      decimals="INF"
      id="ixv-307271"
      unitRef="pure">0.554</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-307272"
      unitRef="pure">0.055</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-307273"
      unitRef="pure">0.007</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019277_QD_A_Member"
      decimals="INF"
      id="ixv-307274"
      unitRef="pure">0.078</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019277_QD_BBB_Member"
      decimals="INF"
      id="ixv-307275"
      unitRef="pure">0.136</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019277_QD_BB_Member"
      decimals="INF"
      id="ixv-307276"
      unitRef="pure">0.041</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019277_QD_B_Member"
      decimals="INF"
      id="ixv-307277"
      unitRef="pure">0.051</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019277_QD_CCCCCC_Member"
      decimals="INF"
      id="ixv-307278"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019277_QD_D_Member"
      decimals="INF"
      id="ixv-307279"
      unitRef="pure">0.000</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019277_QD_NotRated_Member"
      decimals="INF"
      id="ixv-307280"
      unitRef="pure">0.088</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019277_QD_Equities_Member"
      decimals="INF"
      id="ixv-307281"
      unitRef="pure">0.001</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019277_AA_USTreasuryObligations_Member"
      decimals="INF"
      id="ixv-307282"
      unitRef="pure">0.394</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019277_AA_CorporateBonds_Member"
      decimals="INF"
      id="ixv-307283"
      unitRef="pure">0.233</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019277_AA_USGovernmentAgencyMortgageSecurities_Member"
      decimals="INF"
      id="ixv-307284"
      unitRef="pure">0.160</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019277_AA_AssetBackedSecurities_Member"
      decimals="INF"
      id="ixv-307285"
      unitRef="pure">0.085</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019277_AA_CMOsandOtherMortgageRelatedSecurities_Member"
      decimals="INF"
      id="ixv-307286"
      unitRef="pure">0.078</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019277_AA_BankLoanObligations_Member"
      decimals="INF"
      id="ixv-307287"
      unitRef="pure">0.053</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019277_AA_ForeignGovernmentandGovernmentAgencyObligations_Member"
      decimals="INF"
      id="ixv-307288"
      unitRef="pure">0.014</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019277_AA_PreferredSecurities_Member"
      decimals="INF"
      id="ixv-307289"
      unitRef="pure">0.003</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019277_AA_CommonStocks_Member"
      decimals="INF"
      id="ixv-307290"
      unitRef="pure">0.001</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019277_AA_OtherInvestments_Member"
      decimals="INF"
      id="ixv-307291"
      unitRef="pure">0.001</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019277_AA_PreferredStocks_Member"
      decimals="INF"
      id="ixv-307292"
      unitRef="pure">0.000</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019277_AA_Options_Member"
      decimals="INF"
      id="ixv-307293"
      unitRef="pure">0.000</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019277_GD_US_Member"
      decimals="INF"
      id="ixv-307294"
      unitRef="pure">0.873</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019277_GD_GrandCaymanUKOverseasTer_Member"
      decimals="INF"
      id="ixv-307295"
      unitRef="pure">0.045</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019277_GD_GB_Member"
      decimals="INF"
      id="ixv-307296"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019277_GD_MX_Member"
      decimals="INF"
      id="ixv-307297"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019277_GD_BailiwickOfJersey_Member"
      decimals="INF"
      id="ixv-307298"
      unitRef="pure">0.006</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019277_GD_IE_Member"
      decimals="INF"
      id="ixv-307299"
      unitRef="pure">0.006</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019277_GD_DE_Member"
      decimals="INF"
      id="ixv-307300"
      unitRef="pure">0.006</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019277_GD_CH_Member"
      decimals="INF"
      id="ixv-307301"
      unitRef="pure">0.005</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019277_GD_FR_Member"
      decimals="INF"
      id="ixv-307302"
      unitRef="pure">0.005</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019277_GD_Other_Member"
      decimals="INF"
      id="ixv-307303"
      unitRef="pure">0.032</oef:PctOfNav>
    <oef:LargestHoldingsTableTextBlock contextRef="C000019277_ClassMember" id="ixv-5915">TOP HOLDINGS(% of Fund's net assets)

&#160;

&#160;


US Treasury Notes

27.4


&#160;


US Treasury Bonds

12.0


&#160;


Fannie Mae Mortgage pass-thru certificates

5.0


&#160;


Freddie Mac Gold Pool

3.9


&#160;


Ginnie Mae II Pool

3.4


&#160;


Uniform Mortgage Backed Securities

2.7


&#160;


Freddie Mac Multifamily Structured pass-thru certificates

1.6


&#160;


JPMorgan Chase &amp; Co

1.3


&#160;


Morgan Stanley

1.1


&#160;


Bank of America Corp

1.0


&#160;


&#160;

59.4

&#160;



</oef:LargestHoldingsTableTextBlock>
    <oef:PctOfNav
      contextRef="C000019277_TH_0_Member"
      decimals="INF"
      id="ixv-307304"
      unitRef="pure">0.274</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019277_TH_1_Member"
      decimals="INF"
      id="ixv-307305"
      unitRef="pure">0.120</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019277_TH_2_Member"
      decimals="INF"
      id="ixv-307306"
      unitRef="pure">0.050</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019277_TH_3_Member"
      decimals="INF"
      id="ixv-307307"
      unitRef="pure">0.039</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019277_TH_4_Member"
      decimals="INF"
      id="ixv-307308"
      unitRef="pure">0.034</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019277_TH_5_Member"
      decimals="INF"
      id="ixv-307309"
      unitRef="pure">0.027</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019277_TH_6_Member"
      decimals="INF"
      id="ixv-307310"
      unitRef="pure">0.016</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019277_TH_7_Member"
      decimals="INF"
      id="ixv-307311"
      unitRef="pure">0.013</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019277_TH_8_Member"
      decimals="INF"
      id="ixv-307312"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019277_TH_9_Member"
      decimals="INF"
      id="ixv-307313"
      unitRef="pure">0.010</oef:PctOfNav>
    <oef:MaterialFundChngTextBlock contextRef="C000019277_ClassMember" id="ixv-6040">
&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 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="C000019277_ClassMember" id="ixv-6046">&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="C000019277_ClassMember" id="ixv-6048">&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="C000019277_ClassMember" id="ixv-6051">&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="C000019277_ClassMember" id="ixv-6055">&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="C000019277_ClassMember" id="ixv-6066">
&lt;div style="text-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-6124">2026-08-31</dei:DocumentPeriodEndDate>
    <oef:MaterialFundChngNoticeTextBlock contextRef="C000019275_ClassMember" id="ixv-6128">This report describes changes to the Fund that occurred during the reporting period.</oef:MaterialFundChngNoticeTextBlock>
    <oef:FundName contextRef="C000019275_ClassMember" id="ixv-6139">Fidelity&#xae; Total Bond Fund</oef:FundName>
    <oef:ClassName contextRef="C000019275_ClassMember" id="ixv-6142">Fidelity Advisor&#xae; Total Bond Fund Class C</oef:ClassName>
    <dei:TradingSymbol contextRef="C000019275_ClassMember" id="ixv-6146">FCEPX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000019275_ClassMember" id="ixv-6165">This annual shareholder report contains information about Fidelity&#xae; Total Bond Fund for the period September 1, 2025 to August 31, 2026.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000019275_ClassMember" id="ixv-6167">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000019275_ClassMember" id="ixv-6172">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="C000019275_ClassMember" id="ixv-6174">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000019275_ClassMember" id="ixv-6177">1-877-208-0098</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000019275_ClassMember" id="ixv-6180">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000019275_ClassMember" id="ixv-6187">&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;1.51&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="C000019275_ClassMember"
      decimals="0"
      id="ixv-307314"
      unitRef="usd">152</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000019275_ClassMember"
      decimals="INF"
      id="ixv-307315"
      unitRef="pure">0.0151</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000019275_ClassMember" id="ixv-6230">&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 Bond 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="C000019275_ClassMember" id="ixv-6257">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

$10,099


$9,937


$10,780


$11,480


$11,630


$10,194


$10,123


$10,858


$11,249


$11,442



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="C000019275_LG_ClassMember_11YR" id="ixv-6276">&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="C000019275_ClassMember_AsOf_2016"
      decimals="0"
      id="ixv-307316"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019275_ClassMember_AsOf_2017"
      decimals="0"
      id="ixv-307317"
      unitRef="usd">10099</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019275_ClassMember_AsOf_2018"
      decimals="0"
      id="ixv-307318"
      unitRef="usd">9937</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019275_ClassMember_AsOf_2019"
      decimals="0"
      id="ixv-307319"
      unitRef="usd">10780</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019275_ClassMember_AsOf_2020"
      decimals="0"
      id="ixv-307320"
      unitRef="usd">11480</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019275_ClassMember_AsOf_2021"
      decimals="0"
      id="ixv-307321"
      unitRef="usd">11630</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019275_ClassMember_AsOf_2022"
      decimals="0"
      id="ixv-307322"
      unitRef="usd">10194</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019275_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-307323"
      unitRef="usd">10123</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019275_ClassMember_AsOf_2024"
      decimals="0"
      id="ixv-307324"
      unitRef="usd">10858</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019275_ClassMember_AsOf_2025"
      decimals="0"
      id="ixv-307325"
      unitRef="usd">11249</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019275_ClassMember_AsOf_2026"
      decimals="0"
      id="ixv-307326"
      unitRef="usd">11442</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000019275_LG_1_AdditionalIndexMember_11YR"
      id="ixv-6325">&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="C000019275_1_AdditionalIndexMember_AsOf_2016"
      decimals="0"
      id="ixv-307327"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019275_1_AdditionalIndexMember_AsOf_2017"
      decimals="0"
      id="ixv-307328"
      unitRef="usd">10049</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019275_1_AdditionalIndexMember_AsOf_2018"
      decimals="0"
      id="ixv-307329"
      unitRef="usd">9944</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019275_1_AdditionalIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-307330"
      unitRef="usd">10955</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019275_1_AdditionalIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-307331"
      unitRef="usd">11665</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019275_1_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-307332"
      unitRef="usd">11655</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019275_1_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-307333"
      unitRef="usd">10313</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019275_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-307334"
      unitRef="usd">10189</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019275_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-307335"
      unitRef="usd">10933</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019275_1_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-307336"
      unitRef="usd">11276</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019275_1_AdditionalIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-307337"
      unitRef="usd">11489</oef:AccmVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000019275_ClassMember" id="ixv-6426">AVERAGE ANNUAL TOTAL RETURNS:

&#160;

1 Year

5 Year

10 Year


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

-0.04%

-0.63%


1.36%


Class C

0.94%

-0.63%

1.36%


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="C000019275_ClassMember_1YR"
      decimals="INF"
      id="ixv-307338"
      unitRef="pure">-0.0004</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019275_ClassMember_5YR"
      decimals="INF"
      id="ixv-307339"
      unitRef="pure">-0.0063</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019275_ClassMember_10YR"
      decimals="INF"
      id="ixv-307340"
      unitRef="pure">0.0136</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019275_NoLoadClassMember_1YR"
      decimals="INF"
      id="ixv-307341"
      unitRef="pure">0.0094</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019275_NoLoadClassMember_5YR"
      decimals="INF"
      id="ixv-307342"
      unitRef="pure">-0.0063</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019275_NoLoadClassMember_10YR"
      decimals="INF"
      id="ixv-307343"
      unitRef="pure">0.0136</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019275_0_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-307344"
      unitRef="pure">0.0189</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019275_0_BBIndexMember_5YR"
      decimals="INF"
      id="ixv-307345"
      unitRef="pure">-0.0029</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019275_0_BBIndexMember_10YR"
      decimals="INF"
      id="ixv-307346"
      unitRef="pure">0.0140</oef:AvgAnnlRtrPct>
    <oef:UpdPerfInfoLocationTextBlock contextRef="C000019275_ClassMember" id="ixv-6501">&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="C000019275_ClassMember" id="ixv-6513">&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="C000019275_ClassMember" id="ixv-6517">&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="C000019275_ClassMember" id="ixv-6523">&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;$&lt;/span&gt;41,945,078,703&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;6,727&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;118,864,423&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;152&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="C000019275_InstantMember"
      decimals="0"
      id="ixv-307347"
      unitRef="usd">41945078703</us-gaap:AssetsNet>
    <oef:HoldingsCount
      contextRef="C000019275_InstantMember"
      decimals="INF"
      id="ixv-307348"
      unitRef="holding">6727</oef:HoldingsCount>
    <oef:AdvisoryFeesPaidAmt
      contextRef="C000019275_ClassMember"
      decimals="0"
      id="ixv-307349"
      unitRef="usd">118864423</oef:AdvisoryFeesPaidAmt>
    <us-gaap:InvestmentCompanyPortfolioTurnover
      contextRef="C000019275_ClassMember"
      decimals="INF"
      id="ixv-307350"
      unitRef="pure">1.52</us-gaap:InvestmentCompanyPortfolioTurnover>
    <oef:HoldingsTableTextBlock contextRef="C000019275_ClassMember" id="ixv-6598">
&#160;
U.S. Government and U.S. Government Agency Obligations

55.4


AAA

5.5


AA

0.7


A

7.8


BBB

13.6


BB

4.1


B

5.1


CCC,CC,C

1.1


D

0.0


Not Rated

8.8


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 - 5.5&#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 - 0.7&#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 - 7.8&#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 - 13.6&#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 - 4.1&#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;

B - 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;&#160;&#160;


&#160;

CCC,CC,C - 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;

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 - 8.8&#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;

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) - (2.2)% 


&#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

39.4


Corporate Bonds

23.3


U.S. Government Agency - Mortgage Securities

16.0


Asset-Backed Securities

8.5


CMOs and Other Mortgage Related Securities

7.8


Bank Loan Obligations

5.3


Foreign Government and Government Agency Obligations

1.4


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 - 39.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Corporate Bonds - 23.3&#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 - 16.0


&#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 - 5.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Foreign Government and Government Agency Obligations - 1.4


&#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) - (2.2)%


&#160;






United States

87.3


Grand Cayman (UK Overseas Ter)

4.5


United Kingdom

1.1


Mexico

1.1


Bailiwick Of Jersey

0.6


Ireland

0.6


Germany

0.6


Switzerland

0.5


France

0.5


Others

3.2




GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

United States - 87.3&#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) - 4.5&#160;&#160;&#160;&#160;


&#160;

United Kingdom - 1.1&#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 - 0.6&#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;

Germany - 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;

Switzerland - 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;

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;

Others - 3.2&#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>
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      unitRef="pure">0.554</oef:PctOfNav>
    <oef:PctOfNav
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    <oef:PctOfNav
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      decimals="INF"
      id="ixv-307353"
      unitRef="pure">0.007</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019275_QD_A_Member"
      decimals="INF"
      id="ixv-307354"
      unitRef="pure">0.078</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-307355"
      unitRef="pure">0.136</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
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      unitRef="pure">0.041</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-307357"
      unitRef="pure">0.051</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019275_QD_CCCCCC_Member"
      decimals="INF"
      id="ixv-307358"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019275_QD_D_Member"
      decimals="INF"
      id="ixv-307359"
      unitRef="pure">0.000</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019275_QD_NotRated_Member"
      decimals="INF"
      id="ixv-307360"
      unitRef="pure">0.088</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-307361"
      unitRef="pure">0.001</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019275_AA_USTreasuryObligations_Member"
      decimals="INF"
      id="ixv-307362"
      unitRef="pure">0.394</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019275_AA_CorporateBonds_Member"
      decimals="INF"
      id="ixv-307363"
      unitRef="pure">0.233</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019275_AA_USGovernmentAgencyMortgageSecurities_Member"
      decimals="INF"
      id="ixv-307364"
      unitRef="pure">0.160</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019275_AA_AssetBackedSecurities_Member"
      decimals="INF"
      id="ixv-307365"
      unitRef="pure">0.085</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019275_AA_CMOsandOtherMortgageRelatedSecurities_Member"
      decimals="INF"
      id="ixv-307366"
      unitRef="pure">0.078</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019275_AA_BankLoanObligations_Member"
      decimals="INF"
      id="ixv-307367"
      unitRef="pure">0.053</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-307368"
      unitRef="pure">0.014</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019275_AA_PreferredSecurities_Member"
      decimals="INF"
      id="ixv-307369"
      unitRef="pure">0.003</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019275_AA_CommonStocks_Member"
      decimals="INF"
      id="ixv-307370"
      unitRef="pure">0.001</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019275_AA_OtherInvestments_Member"
      decimals="INF"
      id="ixv-307371"
      unitRef="pure">0.001</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019275_AA_PreferredStocks_Member"
      decimals="INF"
      id="ixv-307372"
      unitRef="pure">0.000</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019275_AA_Options_Member"
      decimals="INF"
      id="ixv-307373"
      unitRef="pure">0.000</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019275_GD_US_Member"
      decimals="INF"
      id="ixv-307374"
      unitRef="pure">0.873</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019275_GD_GrandCaymanUKOverseasTer_Member"
      decimals="INF"
      id="ixv-307375"
      unitRef="pure">0.045</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019275_GD_GB_Member"
      decimals="INF"
      id="ixv-307376"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019275_GD_MX_Member"
      decimals="INF"
      id="ixv-307377"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019275_GD_BailiwickOfJersey_Member"
      decimals="INF"
      id="ixv-307378"
      unitRef="pure">0.006</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019275_GD_IE_Member"
      decimals="INF"
      id="ixv-307379"
      unitRef="pure">0.006</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019275_GD_DE_Member"
      decimals="INF"
      id="ixv-307380"
      unitRef="pure">0.006</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019275_GD_CH_Member"
      decimals="INF"
      id="ixv-307381"
      unitRef="pure">0.005</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019275_GD_FR_Member"
      decimals="INF"
      id="ixv-307382"
      unitRef="pure">0.005</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019275_GD_Other_Member"
      decimals="INF"
      id="ixv-307383"
      unitRef="pure">0.032</oef:PctOfNav>
    <oef:LargestHoldingsTableTextBlock contextRef="C000019275_ClassMember" id="ixv-7132">TOP HOLDINGS(% of Fund's net assets)

&#160;

&#160;


US Treasury Notes

27.4


&#160;


US Treasury Bonds

12.0


&#160;


Fannie Mae Mortgage pass-thru certificates

5.0


&#160;


Freddie Mac Gold Pool

3.9


&#160;


Ginnie Mae II Pool

3.4


&#160;


Uniform Mortgage Backed Securities

2.7


&#160;


Freddie Mac Multifamily Structured pass-thru certificates

1.6


&#160;


JPMorgan Chase &amp; Co

1.3


&#160;


Morgan Stanley

1.1


&#160;


Bank of America Corp

1.0


&#160;


&#160;

59.4

&#160;



</oef:LargestHoldingsTableTextBlock>
    <oef:PctOfNav
      contextRef="C000019275_TH_0_Member"
      decimals="INF"
      id="ixv-307384"
      unitRef="pure">0.274</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019275_TH_1_Member"
      decimals="INF"
      id="ixv-307385"
      unitRef="pure">0.120</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019275_TH_2_Member"
      decimals="INF"
      id="ixv-307386"
      unitRef="pure">0.050</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019275_TH_3_Member"
      decimals="INF"
      id="ixv-307387"
      unitRef="pure">0.039</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019275_TH_4_Member"
      decimals="INF"
      id="ixv-307388"
      unitRef="pure">0.034</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019275_TH_5_Member"
      decimals="INF"
      id="ixv-307389"
      unitRef="pure">0.027</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019275_TH_6_Member"
      decimals="INF"
      id="ixv-307390"
      unitRef="pure">0.016</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019275_TH_7_Member"
      decimals="INF"
      id="ixv-307391"
      unitRef="pure">0.013</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019275_TH_8_Member"
      decimals="INF"
      id="ixv-307392"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019275_TH_9_Member"
      decimals="INF"
      id="ixv-307393"
      unitRef="pure">0.010</oef:PctOfNav>
    <oef:MaterialFundChngTextBlock contextRef="C000019275_ClassMember" id="ixv-7257">
&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 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="C000019275_ClassMember" id="ixv-7263">&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="C000019275_ClassMember" id="ixv-7265">&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="C000019275_ClassMember" id="ixv-7268">&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="C000019275_ClassMember" id="ixv-7272">&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="C000019275_ClassMember" id="ixv-7283">
&lt;div style="text-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-7341">2026-08-31</dei:DocumentPeriodEndDate>
    <oef:MaterialFundChngNoticeTextBlock contextRef="C000019273_ClassMember" id="ixv-7345">This report describes changes to the Fund that occurred during the reporting period.</oef:MaterialFundChngNoticeTextBlock>
    <oef:FundName contextRef="C000019273_ClassMember" id="ixv-7356">Fidelity&#xae; Total Bond Fund</oef:FundName>
    <oef:ClassName contextRef="C000019273_ClassMember" id="ixv-7359">Fidelity Advisor&#xae; Total Bond Fund Class A</oef:ClassName>
    <dei:TradingSymbol contextRef="C000019273_ClassMember" id="ixv-7363">FEPAX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000019273_ClassMember" id="ixv-7382">This annual shareholder report contains information about Fidelity&#xae; Total Bond Fund for the period September 1, 2025 to August 31, 2026.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000019273_ClassMember" id="ixv-7384">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000019273_ClassMember" id="ixv-7389">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="C000019273_ClassMember" id="ixv-7391">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000019273_ClassMember" id="ixv-7394">1-877-208-0098</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000019273_ClassMember" id="ixv-7397">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000019273_ClassMember" id="ixv-7404">&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;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>
    <oef:ExpensesPaidAmt
      contextRef="C000019273_ClassMember"
      decimals="0"
      id="ixv-307394"
      unitRef="usd">75</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000019273_ClassMember"
      decimals="INF"
      id="ixv-307395"
      unitRef="pure">0.0075</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000019273_ClassMember" id="ixv-7447">&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 Bond 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="C000019273_ClassMember" id="ixv-7474">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

$9,770


$9,677


$10,580


$11,352


$11,589


$10,246


$10,252


$11,082


$11,480


$11,677



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="C000019273_LG_ClassMember_11YR" id="ixv-7495">&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="C000019273_ClassMember_AsOf_2016"
      decimals="0"
      id="ixv-307396"
      unitRef="usd">9600</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019273_ClassMember_AsOf_2017"
      decimals="0"
      id="ixv-307397"
      unitRef="usd">9770</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019273_ClassMember_AsOf_2018"
      decimals="0"
      id="ixv-307398"
      unitRef="usd">9677</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019273_ClassMember_AsOf_2019"
      decimals="0"
      id="ixv-307399"
      unitRef="usd">10580</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019273_ClassMember_AsOf_2020"
      decimals="0"
      id="ixv-307400"
      unitRef="usd">11352</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019273_ClassMember_AsOf_2021"
      decimals="0"
      id="ixv-307401"
      unitRef="usd">11589</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019273_ClassMember_AsOf_2022"
      decimals="0"
      id="ixv-307402"
      unitRef="usd">10246</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019273_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-307403"
      unitRef="usd">10252</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019273_ClassMember_AsOf_2024"
      decimals="0"
      id="ixv-307404"
      unitRef="usd">11082</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019273_ClassMember_AsOf_2025"
      decimals="0"
      id="ixv-307405"
      unitRef="usd">11480</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019273_ClassMember_AsOf_2026"
      decimals="0"
      id="ixv-307406"
      unitRef="usd">11677</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000019273_LG_1_AdditionalIndexMember_11YR"
      id="ixv-7544">&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="C000019273_1_AdditionalIndexMember_AsOf_2016"
      decimals="0"
      id="ixv-307407"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019273_1_AdditionalIndexMember_AsOf_2017"
      decimals="0"
      id="ixv-307408"
      unitRef="usd">10049</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019273_1_AdditionalIndexMember_AsOf_2018"
      decimals="0"
      id="ixv-307409"
      unitRef="usd">9944</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019273_1_AdditionalIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-307410"
      unitRef="usd">10955</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019273_1_AdditionalIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-307411"
      unitRef="usd">11665</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019273_1_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-307412"
      unitRef="usd">11655</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019273_1_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-307413"
      unitRef="usd">10313</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019273_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-307414"
      unitRef="usd">10189</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019273_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-307415"
      unitRef="usd">10933</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019273_1_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-307416"
      unitRef="usd">11276</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019273_1_AdditionalIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-307417"
      unitRef="usd">11489</oef:AccmVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000019273_ClassMember" id="ixv-7645">AVERAGE ANNUAL TOTAL RETURNS:

&#160;

1 Year

5 Year

10 Year


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

-2.36%

-0.66%


1.56%


Class A (without 4.00% sales charge)

1.71%

0.15%

1.98%


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="C000019273_ClassMember_1YR"
      decimals="INF"
      id="ixv-307418"
      unitRef="pure">-0.0236</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019273_ClassMember_5YR"
      decimals="INF"
      id="ixv-307419"
      unitRef="pure">-0.0066</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019273_ClassMember_10YR"
      decimals="INF"
      id="ixv-307420"
      unitRef="pure">0.0156</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019273_NoLoadClassMember_1YR"
      decimals="INF"
      id="ixv-307421"
      unitRef="pure">0.0171</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019273_NoLoadClassMember_5YR"
      decimals="INF"
      id="ixv-307422"
      unitRef="pure">0.0015</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019273_NoLoadClassMember_10YR"
      decimals="INF"
      id="ixv-307423"
      unitRef="pure">0.0198</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019273_0_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-307424"
      unitRef="pure">0.0189</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019273_0_BBIndexMember_5YR"
      decimals="INF"
      id="ixv-307425"
      unitRef="pure">-0.0029</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019273_0_BBIndexMember_10YR"
      decimals="INF"
      id="ixv-307426"
      unitRef="pure">0.0140</oef:AvgAnnlRtrPct>
    <oef:UpdPerfInfoLocationTextBlock contextRef="C000019273_ClassMember" id="ixv-7718">&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="C000019273_ClassMember" id="ixv-7730">&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="C000019273_ClassMember" id="ixv-7734">&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="C000019273_ClassMember" id="ixv-7740">&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;$&lt;/span&gt;41,945,078,703&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;6,727&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;118,864,423&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;152&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

55.4


AAA

5.5


AA

0.7


A

7.8


BBB

13.6


BB

4.1


B

5.1


CCC,CC,C

1.1


D

0.0


Not Rated

8.8


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 - 5.5&#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 - 0.7&#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 - 7.8&#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 - 13.6&#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 - 4.1&#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;

B - 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;&#160;&#160;


&#160;

CCC,CC,C - 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;

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 - 8.8&#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;

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) - (2.2)% 


&#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

39.4


Corporate Bonds

23.3


U.S. Government Agency - Mortgage Securities

16.0


Asset-Backed Securities

8.5


CMOs and Other Mortgage Related Securities

7.8


Bank Loan Obligations

5.3


Foreign Government and Government Agency Obligations

1.4


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 - 39.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Corporate Bonds - 23.3&#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 - 16.0


&#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 - 5.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Foreign Government and Government Agency Obligations - 1.4


&#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) - (2.2)%


&#160;






United States

87.3


Grand Cayman (UK Overseas Ter)

4.5


United Kingdom

1.1


Mexico

1.1


Bailiwick Of Jersey

0.6


Ireland

0.6


Germany

0.6


Switzerland

0.5


France

0.5


Others

3.2




GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

United States - 87.3&#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) - 4.5&#160;&#160;&#160;&#160;


&#160;

United Kingdom - 1.1&#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 - 0.6&#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;

Germany - 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;

Switzerland - 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;

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;

Others - 3.2&#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;
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    <oef:LargestHoldingsTableTextBlock contextRef="C000019273_ClassMember" id="ixv-8349">TOP HOLDINGS(% of Fund's net assets)

&#160;

&#160;


US Treasury Notes

27.4


&#160;


US Treasury Bonds

12.0


&#160;


Fannie Mae Mortgage pass-thru certificates

5.0


&#160;


Freddie Mac Gold Pool

3.9


&#160;


Ginnie Mae II Pool

3.4


&#160;


Uniform Mortgage Backed Securities

2.7


&#160;


Freddie Mac Multifamily Structured pass-thru certificates

1.6


&#160;


JPMorgan Chase &amp; Co

1.3


&#160;


Morgan Stanley

1.1


&#160;


Bank of America Corp

1.0


&#160;


&#160;

59.4

&#160;



</oef:LargestHoldingsTableTextBlock>
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      id="ixv-307464"
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    <oef:PctOfNav
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    <oef:MaterialFundChngTextBlock contextRef="C000019273_ClassMember" id="ixv-8474">
&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 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="C000019273_ClassMember" id="ixv-8480">&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="C000019273_ClassMember" id="ixv-8482">&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="C000019273_ClassMember" id="ixv-8485">&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="C000019273_ClassMember" id="ixv-8489">&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="C000019273_ClassMember" id="ixv-8500">
&lt;div style="text-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-8558">2026-08-31</dei:DocumentPeriodEndDate>
    <oef:MaterialFundChngNoticeTextBlock contextRef="C000203458_ClassMember" id="ixv-8562">This report describes changes to the Fund that occurred during the reporting period.</oef:MaterialFundChngNoticeTextBlock>
    <oef:FundName contextRef="C000203458_ClassMember" id="ixv-8573">Fidelity&#xae; Series Government Bond Index Fund</oef:FundName>
    <oef:ClassName contextRef="C000203458_ClassMember" id="ixv-8576">Fidelity&#xae; Series Government Bond Index Fund</oef:ClassName>
    <dei:TradingSymbol contextRef="C000203458_ClassMember" id="ixv-8580">FHNFX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000203458_ClassMember" id="ixv-8599">This annual shareholder report contains information about Fidelity&#xae; Series Government Bond Index Fund for the period September 1, 2025 to August 31, 2026.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000203458_ClassMember" id="ixv-8601">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000203458_ClassMember" id="ixv-8606">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.</oef:AddlInfoTextBlock>
    <oef:AddlInfoWebsite contextRef="C000203458_ClassMember" id="ixv-8608">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000203458_ClassMember" id="ixv-8611">1-800-544-8544</oef:AddlInfoPhoneNumber>
    <oef:ExpensesTextBlock contextRef="C000203458_ClassMember" id="ixv-8618">&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 $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:51%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity&#xae; Series Government Bond Index Fund&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:21%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&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
      contextRef="C000203458_ClassMember"
      decimals="0"
      id="ixv-307474"
      unitRef="usd">0</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000203458_ClassMember"
      decimals="INF"
      id="ixv-307475"
      unitRef="pure">0.0000</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000203458_ClassMember" id="ixv-8671">&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;We construct the portfolio using optimization. This approach minimizes the differences between risk exposures of the fund relative to the index. We attempt to hold all positions held by the index in the same relative proportions.&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;Exposures include duration, key-rate durations, sector, and other factors.&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="C000203458_ClassMember" id="ixv-8686">How did the Fund perform over the life of Fund?

 &#160;&#160;
CUMULATIVE PERFORMANCE
August 17, 2018 through August 31, 2026. 
Initial investment of $10,000.
Fidelity&#xae; Series Government Bond Index Fund


$10,000

$10,010


$11,052


$11,781


$11,563


$10,330


$10,128


$10,747


$11,012



Bloomberg U.S. Government Bond Index


$10,000

$10,019


$11,052


$11,816


$11,578


$10,340


$10,133


$10,744


$11,007



Bloomberg U.S. Aggregate Bond Index


$10,000

$10,014


$11,033


$11,747


$11,737


$10,386


$10,262


$11,010


$11,356



&#160;

2018

2019

2020

2021

2022

2023

2024

2025

2026









&#160;
</oef:LineGraphTableTextBlock>
    <oef:LineGraphAndTableMeasureName contextRef="C000203458_LG_ClassMember_9YR" id="ixv-8705">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity&#xae; Series Government Bond Index Fund&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000203458_ClassMember_AsOf_2018"
      decimals="0"
      id="ixv-307476"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000203458_ClassMember_AsOf_2019"
      decimals="0"
      id="ixv-307477"
      unitRef="usd">10010</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000203458_ClassMember_AsOf_2020"
      decimals="0"
      id="ixv-307478"
      unitRef="usd">11052</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000203458_ClassMember_AsOf_2021"
      decimals="0"
      id="ixv-307479"
      unitRef="usd">11781</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000203458_ClassMember_AsOf_2022"
      decimals="0"
      id="ixv-307480"
      unitRef="usd">11563</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000203458_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-307481"
      unitRef="usd">10330</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000203458_ClassMember_AsOf_2024"
      decimals="0"
      id="ixv-307482"
      unitRef="usd">10128</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000203458_ClassMember_AsOf_2025"
      decimals="0"
      id="ixv-307483"
      unitRef="usd">10747</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000203458_ClassMember_AsOf_2026"
      decimals="0"
      id="ixv-307484"
      unitRef="usd">11012</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000203458_LG_1_AdditionalIndexMember_9YR"
      id="ixv-8746">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg U.S. Government Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000203458_1_AdditionalIndexMember_AsOf_2018"
      decimals="0"
      id="ixv-307485"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000203458_1_AdditionalIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-307486"
      unitRef="usd">10019</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000203458_1_AdditionalIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-307487"
      unitRef="usd">11052</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000203458_1_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-307488"
      unitRef="usd">11816</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000203458_1_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-307489"
      unitRef="usd">11578</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000203458_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-307490"
      unitRef="usd">10340</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000203458_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-307491"
      unitRef="usd">10133</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000203458_1_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-307492"
      unitRef="usd">10744</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000203458_1_AdditionalIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-307493"
      unitRef="usd">11007</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000203458_LG_2_AdditionalIndexMember_9YR"
      id="ixv-8787">&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="C000203458_2_AdditionalIndexMember_AsOf_2018"
      decimals="0"
      id="ixv-307494"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000203458_2_AdditionalIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-307495"
      unitRef="usd">10014</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000203458_2_AdditionalIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-307496"
      unitRef="usd">11033</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000203458_2_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-307497"
      unitRef="usd">11747</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000203458_2_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-307498"
      unitRef="usd">11737</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000203458_2_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-307499"
      unitRef="usd">10386</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000203458_2_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-307500"
      unitRef="usd">10262</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000203458_2_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-307501"
      unitRef="usd">11010</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000203458_2_AdditionalIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-307502"
      unitRef="usd">11356</oef:AccmVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000203458_ClassMember" id="ixv-8874">AVERAGE ANNUAL TOTAL RETURNS:

&#160;

1 Year

5 Year

Life of Fund&#160;A


Fidelity&#xae; Series Government Bond Index Fund

1.19%

-0.74%

1.35%


Bloomberg U.S. Government Bond Index

1.23%


-0.77%


1.35%


Bloomberg U.S. Aggregate Bond Index

1.89%


-0.29%


1.83%




A&#160; &#160;From August 17, 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="C000203458_NoLoadClassMember_1YR"
      decimals="INF"
      id="ixv-307503"
      unitRef="pure">0.0119</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000203458_NoLoadClassMember_5YR"
      decimals="INF"
      id="ixv-307504"
      unitRef="pure">-0.0074</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000203458_NoLoadClassMember_2025-09-01_2026-08-31"
      decimals="INF"
      id="ixv-307505"
      unitRef="pure">0.0135</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000203458_0_AdditionalIndexMember_1YR"
      decimals="INF"
      id="ixv-307506"
      unitRef="pure">0.0123</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000203458_0_AdditionalIndexMember_5YR"
      decimals="INF"
      id="ixv-307507"
      unitRef="pure">-0.0077</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000203458_0_AdditionalIndexMember_LOC"
      decimals="INF"
      id="ixv-307508"
      unitRef="pure">0.0135</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000203458_1_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-307509"
      unitRef="pure">0.0189</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000203458_1_BBIndexMember_5YR"
      decimals="INF"
      id="ixv-307510"
      unitRef="pure">-0.0029</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000203458_1_BBIndexMember_LOC"
      decimals="INF"
      id="ixv-307511"
      unitRef="pure">0.0183</oef:AvgAnnlRtrPct>
    <oef:PerfInceptionDate
      contextRef="C000203458_Perf_2018-08-17_ClassMember"
      id="ixv-8946">2018-08-17</oef:PerfInceptionDate>
    <oef:UpdPerfInfoLocationTextBlock contextRef="C000203458_ClassMember" id="ixv-8956">&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="C000203458_ClassMember" id="ixv-8968">&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="C000203458_ClassMember" id="ixv-8972">&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="C000203458_ClassMember" id="ixv-8978">&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;$&lt;/span&gt;1,403,609,158&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;264&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&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;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;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-307512"
      unitRef="usd">1403609158</us-gaap:AssetsNet>
    <oef:HoldingsCount
      contextRef="C000203458_InstantMember"
      decimals="INF"
      id="ixv-307513"
      unitRef="holding">264</oef:HoldingsCount>
    <oef:AdvisoryFeesPaidAmt
      contextRef="C000203458_ClassMember"
      decimals="0"
      id="ixv-307514"
      unitRef="usd">0</oef:AdvisoryFeesPaidAmt>
    <us-gaap:InvestmentCompanyPortfolioTurnover
      contextRef="C000203458_ClassMember"
      decimals="INF"
      id="ixv-307515"
      unitRef="pure">0.36</us-gaap:InvestmentCompanyPortfolioTurnover>
    <oef:HoldingsTableTextBlock contextRef="C000203458_ClassMember" id="ixv-9053">
&#160;
COUPON DISTRIBUTION 
(% of Fund's net assets)


0.01 - 0.99%

2.8

&#160;


1 - 1.99%

13.6

&#160;


2 - 2.99%

8.7

&#160;


3 - 3.99%

33.3

&#160;


4 - 4.99%

37.7

&#160;


5 - 5.99%

2.0

&#160;


6 - 6.99%

0.7

&#160;


7 - 7.99%

0.1

&#160;




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

97.9


U.S. Government Agency Obligations

1.0


Short-Term Investments and Net Other Assets (Liabilities)

1.1




ASSET ALLOCATION (% of Fund's net assets)


&#160;



&#160;

U.S. Treasury Obligations - 97.9&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

U.S. Government Agency Obligations - 1.0


&#160;

Short-Term Investments and Net Other Assets (Liabilities) - 1.1


&#160;






</oef:HoldingsTableTextBlock>
    <oef:PctOfNav
      contextRef="C000203458_CD_0_Member"
      decimals="INF"
      id="ixv-307516"
      unitRef="pure">0.028</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000203458_CD_1_Member"
      decimals="INF"
      id="ixv-307517"
      unitRef="pure">0.136</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000203458_CD_2_Member"
      decimals="INF"
      id="ixv-307518"
      unitRef="pure">0.087</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000203458_CD_3_Member"
      decimals="INF"
      id="ixv-307519"
      unitRef="pure">0.333</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000203458_CD_4_Member"
      decimals="INF"
      id="ixv-307520"
      unitRef="pure">0.377</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000203458_CD_5_Member"
      decimals="INF"
      id="ixv-307521"
      unitRef="pure">0.020</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000203458_CD_6_Member"
      decimals="INF"
      id="ixv-307522"
      unitRef="pure">0.007</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000203458_CD_7_Member"
      decimals="INF"
      id="ixv-307523"
      unitRef="pure">0.001</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000203458_AA_USTreasuryObligations_Member"
      decimals="INF"
      id="ixv-307524"
      unitRef="pure">0.979</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000203458_AA_USGovernmentAgencyObligations_Member"
      decimals="INF"
      id="ixv-307525"
      unitRef="pure">0.010</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000203458_AA_ShortTermInvestmentsandNetOtherAssetsLiabilities_Member"
      decimals="INF"
      id="ixv-307526"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:LargestHoldingsTableTextBlock contextRef="C000203458_ClassMember" id="ixv-9211">TOP HOLDINGS(% of Fund's net assets)

&#160;

&#160;


US Treasury Notes

75.7


&#160;


US Treasury Bonds

22.2


&#160;


Federal Home Loan Bank

0.3


&#160;


Fannie Mae

0.3


&#160;


Tennessee Valley Authority

0.2


&#160;


Federal Farm Credit Banks Funding Corp

0.1


&#160;


Freddie Mac Non Gold Pool

0.1


&#160;


&#160;

98.9

&#160;



</oef:LargestHoldingsTableTextBlock>
    <oef:PctOfNav
      contextRef="C000203458_TH_0_Member"
      decimals="INF"
      id="ixv-307527"
      unitRef="pure">0.757</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000203458_TH_1_Member"
      decimals="INF"
      id="ixv-307528"
      unitRef="pure">0.222</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000203458_TH_2_Member"
      decimals="INF"
      id="ixv-307529"
      unitRef="pure">0.003</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000203458_TH_3_Member"
      decimals="INF"
      id="ixv-307530"
      unitRef="pure">0.003</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000203458_TH_4_Member"
      decimals="INF"
      id="ixv-307531"
      unitRef="pure">0.002</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000203458_TH_5_Member"
      decimals="INF"
      id="ixv-307532"
      unitRef="pure">0.001</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000203458_TH_6_Member"
      decimals="INF"
      id="ixv-307533"
      unitRef="pure">0.001</oef:PctOfNav>
    <oef:MaterialFundChngTextBlock contextRef="C000203458_ClassMember" id="ixv-9306">
&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;.&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 risks 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="C000203458_ClassMember" id="ixv-9312">&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;.&lt;/span&gt;</oef:SummaryOfChngLegendTextBlock>
    <oef:UpdProspectusWebAddress contextRef="C000203458_ClassMember" id="ixv-9314">&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="C000203458_ClassMember" id="ixv-9317">&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:MaterialFundChngRisksChngTextBlock contextRef="C000203458_ClassMember" id="ixv-9329">
&lt;div style="text-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 risks 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:MaterialFundChngRisksChngTextBlock>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-9387">2026-08-31</dei:DocumentPeriodEndDate>
    <oef:MaterialFundChngNoticeTextBlock contextRef="C000019284_ClassMember" id="ixv-9391">This report describes changes to the Fund that occurred during the reporting period.</oef:MaterialFundChngNoticeTextBlock>
    <oef:FundName contextRef="C000019284_ClassMember" id="ixv-9402">Fidelity&#xae; Intermediate Government Income Fund</oef:FundName>
    <oef:ClassName contextRef="C000019284_ClassMember" id="ixv-9405">Fidelity&#xae; Intermediate Government Income Fund</oef:ClassName>
    <dei:TradingSymbol contextRef="C000019284_ClassMember" id="ixv-9409">FSTGX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000019284_ClassMember" id="ixv-9428">This annual shareholder report contains information about Fidelity&#xae; Intermediate Government Income Fund for the period September 1, 2025 to August 31, 2026.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000019284_ClassMember" id="ixv-9430">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000019284_ClassMember" id="ixv-9435">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="C000019284_ClassMember" id="ixv-9437">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000019284_ClassMember" id="ixv-9440">1-800-544-8544</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000019284_ClassMember" id="ixv-9443">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000019284_ClassMember" id="ixv-9450">&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 $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:51%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity&#xae; Intermediate Government Income Fund&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:21%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&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="C000019284_ClassMember"
      decimals="0"
      id="ixv-307534"
      unitRef="usd">45</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000019284_ClassMember"
      decimals="INF"
      id="ixv-307535"
      unitRef="pure">0.0045</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000019284_ClassMember" id="ixv-9493">&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, fast-growing government debt 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, security selection among conventional 30-year mortgage pools with specified characteristics contributed to the fund's performance versus the benchmark, the Bloomberg Intermediate Government Bond 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;An overweight in short-duration Freddie Mac multifamily securities boosted relative performance, as did a pay-fixed position in two-year interest-rate swaps.&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 longer duration (interest rate) positioning detracted versus the benchmark for the 12 months.&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;Lastly, a small position in Treasury Inflation-Protected Securities modestly hurt relative 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="C000019284_ClassMember" id="ixv-9514">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 Government Income Fund


$10,000

$10,008


$9,855


$10,575


$11,112


$10,992


$10,096


$10,024


$10,619


$11,020


$11,179



Bloomberg U.S. Intermediate Government Bond Index


$10,000

$10,009


$9,883


$10,619


$11,196


$11,122


$10,285


$10,271


$10,914


$11,376


$11,549



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="C000019284_LG_ClassMember_11YR" id="ixv-9533">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity&#xae; Intermediate Government Income Fund&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000019284_ClassMember_AsOf_2016"
      decimals="0"
      id="ixv-307536"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019284_ClassMember_AsOf_2017"
      decimals="0"
      id="ixv-307537"
      unitRef="usd">10008</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019284_ClassMember_AsOf_2018"
      decimals="0"
      id="ixv-307538"
      unitRef="usd">9855</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019284_ClassMember_AsOf_2019"
      decimals="0"
      id="ixv-307539"
      unitRef="usd">10575</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019284_ClassMember_AsOf_2020"
      decimals="0"
      id="ixv-307540"
      unitRef="usd">11112</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019284_ClassMember_AsOf_2021"
      decimals="0"
      id="ixv-307541"
      unitRef="usd">10992</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019284_ClassMember_AsOf_2022"
      decimals="0"
      id="ixv-307542"
      unitRef="usd">10096</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019284_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-307543"
      unitRef="usd">10024</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019284_ClassMember_AsOf_2024"
      decimals="0"
      id="ixv-307544"
      unitRef="usd">10619</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019284_ClassMember_AsOf_2025"
      decimals="0"
      id="ixv-307545"
      unitRef="usd">11020</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019284_ClassMember_AsOf_2026"
      decimals="0"
      id="ixv-307546"
      unitRef="usd">11179</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000019284_LG_1_AdditionalIndexMember_11YR"
      id="ixv-9582">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg U.S. Intermediate Government Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000019284_1_AdditionalIndexMember_AsOf_2016"
      decimals="0"
      id="ixv-307547"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019284_1_AdditionalIndexMember_AsOf_2017"
      decimals="0"
      id="ixv-307548"
      unitRef="usd">10009</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019284_1_AdditionalIndexMember_AsOf_2018"
      decimals="0"
      id="ixv-307549"
      unitRef="usd">9883</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019284_1_AdditionalIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-307550"
      unitRef="usd">10619</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019284_1_AdditionalIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-307551"
      unitRef="usd">11196</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019284_1_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-307552"
      unitRef="usd">11122</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019284_1_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-307553"
      unitRef="usd">10285</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019284_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-307554"
      unitRef="usd">10271</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019284_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-307555"
      unitRef="usd">10914</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019284_1_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-307556"
      unitRef="usd">11376</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019284_1_AdditionalIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-307557"
      unitRef="usd">11549</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000019284_LG_2_AdditionalIndexMember_11YR"
      id="ixv-9631">&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="C000019284_2_AdditionalIndexMember_AsOf_2016"
      decimals="0"
      id="ixv-307558"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019284_2_AdditionalIndexMember_AsOf_2017"
      decimals="0"
      id="ixv-307559"
      unitRef="usd">10049</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019284_2_AdditionalIndexMember_AsOf_2018"
      decimals="0"
      id="ixv-307560"
      unitRef="usd">9944</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019284_2_AdditionalIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-307561"
      unitRef="usd">10955</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019284_2_AdditionalIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-307562"
      unitRef="usd">11665</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019284_2_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-307563"
      unitRef="usd">11655</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019284_2_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-307564"
      unitRef="usd">10313</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019284_2_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-307565"
      unitRef="usd">10189</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019284_2_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-307566"
      unitRef="usd">10933</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019284_2_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-307567"
      unitRef="usd">11276</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019284_2_AdditionalIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-307568"
      unitRef="usd">11489</oef:AccmVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000019284_ClassMember" id="ixv-9732">AVERAGE ANNUAL TOTAL RETURNS:

&#160;

1 Year

5 Year

10 Year


Fidelity&#xae; Intermediate Government Income Fund

1.44%

0.34%

1.12%


Bloomberg U.S. Intermediate Government Bond Index

1.52%


0.76%


1.45%


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="C000019284_NoLoadClassMember_1YR"
      decimals="INF"
      id="ixv-307569"
      unitRef="pure">0.0144</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019284_NoLoadClassMember_5YR"
      decimals="INF"
      id="ixv-307570"
      unitRef="pure">0.0034</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019284_NoLoadClassMember_10YR"
      decimals="INF"
      id="ixv-307571"
      unitRef="pure">0.0112</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019284_0_AdditionalIndexMember_1YR"
      decimals="INF"
      id="ixv-307572"
      unitRef="pure">0.0152</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019284_0_AdditionalIndexMember_5YR"
      decimals="INF"
      id="ixv-307573"
      unitRef="pure">0.0076</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019284_0_AdditionalIndexMember_10YR"
      decimals="INF"
      id="ixv-307574"
      unitRef="pure">0.0145</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019284_1_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-307575"
      unitRef="pure">0.0189</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019284_1_BBIndexMember_5YR"
      decimals="INF"
      id="ixv-307576"
      unitRef="pure">-0.0029</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019284_1_BBIndexMember_10YR"
      decimals="INF"
      id="ixv-307577"
      unitRef="pure">0.0140</oef:AvgAnnlRtrPct>
    <oef:UpdPerfInfoLocationTextBlock contextRef="C000019284_ClassMember" id="ixv-9803">&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="C000019284_ClassMember" id="ixv-9815">&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="C000019284_ClassMember" id="ixv-9819">&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="C000019284_ClassMember" id="ixv-9825">&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;$&lt;/span&gt;516,510,363&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;185&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;1,419,547&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;196&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="C000019284_InstantMember"
      decimals="0"
      id="ixv-307578"
      unitRef="usd">516510363</us-gaap:AssetsNet>
    <oef:HoldingsCount
      contextRef="C000019284_InstantMember"
      decimals="INF"
      id="ixv-307579"
      unitRef="holding">185</oef:HoldingsCount>
    <oef:AdvisoryFeesPaidAmt
      contextRef="C000019284_ClassMember"
      decimals="0"
      id="ixv-307580"
      unitRef="usd">1419547</oef:AdvisoryFeesPaidAmt>
    <us-gaap:InvestmentCompanyPortfolioTurnover
      contextRef="C000019284_ClassMember"
      decimals="INF"
      id="ixv-307581"
      unitRef="pure">1.96</us-gaap:InvestmentCompanyPortfolioTurnover>
    <oef:HoldingsTableTextBlock contextRef="C000019284_ClassMember" id="ixv-9900">
&#160;
COUPON DISTRIBUTION 
(% of Fund's net assets)


1 - 1.99%

10.8

&#160;


2 - 2.99%

5.5

&#160;


3 - 3.99%

45.8

&#160;


4 - 4.99%

32.0

&#160;


5 - 5.99%

-0.6

&#160;


6 - 6.99%

1.6

&#160;




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

81.7


CMOs and Other Mortgage Related Securities

12.5


U.S. Government Agency Obligations

3.0


Options

0.3


Short-Term Investments and Net Other Assets (Liabilities)

4.6




ASSET ALLOCATION (% of Fund's net assets)


&#160;



&#160;

U.S. Treasury Obligations - 81.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

CMOs and Other Mortgage Related Securities - 12.5


&#160;

U.S. Government Agency Obligations - 3.0


&#160;

Options - 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;

Short-Term Investments and Net Other Assets (Liabilities) - 4.6


U.S. Government Agency - Mortgage Securities - (2.1)%


&#160;






</oef:HoldingsTableTextBlock>
    <oef:PctOfNav
      contextRef="C000019284_CD_0_Member"
      decimals="INF"
      id="ixv-307582"
      unitRef="pure">0.108</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019284_CD_1_Member"
      decimals="INF"
      id="ixv-307583"
      unitRef="pure">0.055</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019284_CD_2_Member"
      decimals="INF"
      id="ixv-307584"
      unitRef="pure">0.458</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019284_CD_3_Member"
      decimals="INF"
      id="ixv-307585"
      unitRef="pure">0.320</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019284_CD_4_Member"
      decimals="INF"
      id="ixv-307586"
      unitRef="pure">-0.006</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019284_CD_5_Member"
      decimals="INF"
      id="ixv-307587"
      unitRef="pure">0.016</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019284_AA_USTreasuryObligations_Member"
      decimals="INF"
      id="ixv-307588"
      unitRef="pure">0.817</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019284_AA_CMOsandOtherMortgageRelatedSecurities_Member"
      decimals="INF"
      id="ixv-307589"
      unitRef="pure">0.125</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019284_AA_USGovernmentAgencyObligations_Member"
      decimals="INF"
      id="ixv-307590"
      unitRef="pure">0.030</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019284_AA_Options_Member"
      decimals="INF"
      id="ixv-307591"
      unitRef="pure">0.003</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019284_AA_ShortTermInvestmentsandNetOtherAssetsLiabilities_Member"
      decimals="INF"
      id="ixv-307592"
      unitRef="pure">0.046</oef:PctOfNav>
    <oef:LargestHoldingsTableTextBlock contextRef="C000019284_ClassMember" id="ixv-10071">TOP HOLDINGS(% of Fund's net assets)

&#160;

&#160;


US Treasury Notes

80.3


&#160;


Freddie Mac Multifamily Structured pass-thru certificates

9.7


&#160;


Freddie Mac Gold Pool

2.3


&#160;


Federal Farm Credit Banks Funding Corp

1.6


&#160;


Federal Home Loan Bank

1.4


&#160;


US Treasury Bonds

1.4


&#160;


Fannie Mae Mortgage pass-thru certificates

1.1


&#160;


Fannie Mae Guaranteed REMIC

0.7


&#160;


Ginnie Mae I Pool

0.1


&#160;


Freddie Mac Non Gold Pool

0.1


&#160;


&#160;

98.7

&#160;



</oef:LargestHoldingsTableTextBlock>
    <oef:PctOfNav
      contextRef="C000019284_TH_0_Member"
      decimals="INF"
      id="ixv-307593"
      unitRef="pure">0.803</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019284_TH_1_Member"
      decimals="INF"
      id="ixv-307594"
      unitRef="pure">0.097</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019284_TH_2_Member"
      decimals="INF"
      id="ixv-307595"
      unitRef="pure">0.023</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019284_TH_3_Member"
      decimals="INF"
      id="ixv-307596"
      unitRef="pure">0.016</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019284_TH_4_Member"
      decimals="INF"
      id="ixv-307597"
      unitRef="pure">0.014</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019284_TH_5_Member"
      decimals="INF"
      id="ixv-307598"
      unitRef="pure">0.014</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019284_TH_6_Member"
      decimals="INF"
      id="ixv-307599"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019284_TH_7_Member"
      decimals="INF"
      id="ixv-307600"
      unitRef="pure">0.007</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019284_TH_8_Member"
      decimals="INF"
      id="ixv-307601"
      unitRef="pure">0.001</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019284_TH_9_Member"
      decimals="INF"
      id="ixv-307602"
      unitRef="pure">0.001</oef:PctOfNav>
    <oef:MaterialFundChngTextBlock contextRef="C000019284_ClassMember" id="ixv-10196">
&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 modified its principal investment risks 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="C000019284_ClassMember" id="ixv-10202">&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="C000019284_ClassMember" id="ixv-10204">&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="C000019284_ClassMember" id="ixv-10207">&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="C000019284_ClassMember" id="ixv-10211">&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:MaterialFundChngRisksChngTextBlock contextRef="C000019284_ClassMember" id="ixv-10222">
&lt;div style="text-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 risks 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:MaterialFundChngRisksChngTextBlock>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-10280">2026-08-31</dei:DocumentPeriodEndDate>
    <oef:MaterialFundChngNoticeTextBlock contextRef="C000019283_ClassMember" id="ixv-10284">This report describes changes to the Fund that occurred during the reporting period.</oef:MaterialFundChngNoticeTextBlock>
    <oef:FundName contextRef="C000019283_ClassMember" id="ixv-10295">Fidelity&#xae; Government Income Fund</oef:FundName>
    <oef:ClassName contextRef="C000019283_ClassMember" id="ixv-10298">Fidelity&#xae; Government Income Fund</oef:ClassName>
    <dei:TradingSymbol contextRef="C000019283_ClassMember" id="ixv-10302">FGOVX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000019283_ClassMember" id="ixv-10321">This annual shareholder report contains information about Fidelity&#xae; Government Income Fund for the period September 1, 2025 to August 31, 2026.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000019283_ClassMember" id="ixv-10323">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000019283_ClassMember" id="ixv-10328">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="C000019283_ClassMember" id="ixv-10330">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000019283_ClassMember" id="ixv-10333">1-800-544-8544</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000019283_ClassMember" id="ixv-10336">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000019283_ClassMember" id="ixv-10343">&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 $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:51%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity&#xae; Government Income Fund&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:21%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&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="C000019283_ClassMember"
      decimals="0"
      id="ixv-307603"
      unitRef="usd">45</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000019283_ClassMember"
      decimals="INF"
      id="ixv-307604"
      unitRef="pure">0.0045</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000019283_ClassMember" id="ixv-10386">&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, fast-growing government debt 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, an overweight in Ginnie Mae securities with coupons of 2.0% and 2.5% contributed to the fund's performance versus the Bloomberg 75% U.S. Government/25% U.S. Mortgage-Backed Securities Blended 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;An overweight in conventional 30-year mortgage pools with specified characteristics and coupons of 2.5% and higher boosted relative performance, as did an overweight in short-duration Freddie Mac multifamily securities.&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 underweight in conventional 30-year mortgage-backed securities with a coupon of 2% detracted versus the index.&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 longer duration (interest rate) positioning hurt relative performance.&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;Lastly, a small position in Treasury Inflation-Protected Securities detracted.&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="C000019283_ClassMember" id="ixv-10410">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; Government Income Fund


$10,000

$9,958


$9,801


$10,715


$11,351


$11,174


$9,963


$9,719


$10,338


$10,577


$10,753



Bloomberg 75% U.S. Government/25% U.S. Mortgage-Backed Securities Blended Index


$10,000

$9,957


$9,832


$10,765


$11,447


$11,269


$10,091


$9,888


$10,520


$10,801


$10,982



Bloomberg U.S. Government Bond Index


$10,000

$9,916


$9,767


$10,774


$11,519


$11,287


$10,080


$9,878


$10,474


$10,730


$10,862



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="C000019283_LG_ClassMember_11YR" id="ixv-10429">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity&#xae; Government Income Fund&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000019283_ClassMember_AsOf_2016"
      decimals="0"
      id="ixv-307605"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019283_ClassMember_AsOf_2017"
      decimals="0"
      id="ixv-307606"
      unitRef="usd">9958</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019283_ClassMember_AsOf_2018"
      decimals="0"
      id="ixv-307607"
      unitRef="usd">9801</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019283_ClassMember_AsOf_2019"
      decimals="0"
      id="ixv-307608"
      unitRef="usd">10715</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019283_ClassMember_AsOf_2020"
      decimals="0"
      id="ixv-307609"
      unitRef="usd">11351</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019283_ClassMember_AsOf_2021"
      decimals="0"
      id="ixv-307610"
      unitRef="usd">11174</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019283_ClassMember_AsOf_2022"
      decimals="0"
      id="ixv-307611"
      unitRef="usd">9963</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019283_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-307612"
      unitRef="usd">9719</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019283_ClassMember_AsOf_2024"
      decimals="0"
      id="ixv-307613"
      unitRef="usd">10338</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019283_ClassMember_AsOf_2025"
      decimals="0"
      id="ixv-307614"
      unitRef="usd">10577</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019283_ClassMember_AsOf_2026"
      decimals="0"
      id="ixv-307615"
      unitRef="usd">10753</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000019283_LG_1_AdditionalIndexMember_11YR"
      id="ixv-10478">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg 75% U.S. Government/25% U.S. Mortgage-Backed Securities Blended Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000019283_1_AdditionalIndexMember_AsOf_2016"
      decimals="0"
      id="ixv-307616"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019283_1_AdditionalIndexMember_AsOf_2017"
      decimals="0"
      id="ixv-307617"
      unitRef="usd">9957</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019283_1_AdditionalIndexMember_AsOf_2018"
      decimals="0"
      id="ixv-307618"
      unitRef="usd">9832</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019283_1_AdditionalIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-307619"
      unitRef="usd">10765</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019283_1_AdditionalIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-307620"
      unitRef="usd">11447</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019283_1_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-307621"
      unitRef="usd">11269</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019283_1_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-307622"
      unitRef="usd">10091</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019283_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-307623"
      unitRef="usd">9888</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019283_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-307624"
      unitRef="usd">10520</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019283_1_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-307625"
      unitRef="usd">10801</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019283_1_AdditionalIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-307626"
      unitRef="usd">10982</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000019283_LG_2_AdditionalIndexMember_11YR"
      id="ixv-10527">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg U.S. Government Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000019283_2_AdditionalIndexMember_AsOf_2016"
      decimals="0"
      id="ixv-307627"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019283_2_AdditionalIndexMember_AsOf_2017"
      decimals="0"
      id="ixv-307628"
      unitRef="usd">9916</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019283_2_AdditionalIndexMember_AsOf_2018"
      decimals="0"
      id="ixv-307629"
      unitRef="usd">9767</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019283_2_AdditionalIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-307630"
      unitRef="usd">10774</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019283_2_AdditionalIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-307631"
      unitRef="usd">11519</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019283_2_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-307632"
      unitRef="usd">11287</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019283_2_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-307633"
      unitRef="usd">10080</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019283_2_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-307634"
      unitRef="usd">9878</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019283_2_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-307635"
      unitRef="usd">10474</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019283_2_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-307636"
      unitRef="usd">10730</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019283_2_AdditionalIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-307637"
      unitRef="usd">10862</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000019283_0_LG_BBIndexMember_11YR"
      id="ixv-10576">&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="C000019283_0_BBIndexMember_AsOf_2016"
      decimals="0"
      id="ixv-307638"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019283_0_BBIndexMember_AsOf_2017"
      decimals="0"
      id="ixv-307639"
      unitRef="usd">10049</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019283_0_BBIndexMember_AsOf_2018"
      decimals="0"
      id="ixv-307640"
      unitRef="usd">9944</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019283_0_BBIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-307641"
      unitRef="usd">10955</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019283_0_BBIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-307642"
      unitRef="usd">11665</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019283_0_BBIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-307643"
      unitRef="usd">11655</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019283_0_BBIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-307644"
      unitRef="usd">10313</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019283_0_BBIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-307645"
      unitRef="usd">10189</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019283_0_BBIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-307646"
      unitRef="usd">10933</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019283_0_BBIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-307647"
      unitRef="usd">11276</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000019283_0_BBIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-307648"
      unitRef="usd">11489</oef:AccmVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000019283_ClassMember" id="ixv-10676">AVERAGE ANNUAL TOTAL RETURNS:

&#160;

1 Year

5 Year

10 Year


Fidelity&#xae; Government Income Fund

1.66%

-0.77%

0.73%


Bloomberg 75% U.S. Government/25% U.S. Mortgage-Backed Securities Blended Index

1.67%


-0.51%


0.94%


Bloomberg U.S. Government Bond Index

1.23%


-0.77%


0.83%


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="C000019283_NoLoadClassMember_1YR"
      decimals="INF"
      id="ixv-307649"
      unitRef="pure">0.0166</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019283_NoLoadClassMember_5YR"
      decimals="INF"
      id="ixv-307650"
      unitRef="pure">-0.0077</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019283_NoLoadClassMember_10YR"
      decimals="INF"
      id="ixv-307651"
      unitRef="pure">0.0073</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019283_0_AdditionalIndexMember_1YR"
      decimals="INF"
      id="ixv-307652"
      unitRef="pure">0.0167</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019283_0_AdditionalIndexMember_5YR"
      decimals="INF"
      id="ixv-307653"
      unitRef="pure">-0.0051</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019283_0_AdditionalIndexMember_10YR"
      decimals="INF"
      id="ixv-307654"
      unitRef="pure">0.0094</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019283_1_AdditionalIndexMember_1YR"
      decimals="INF"
      id="ixv-307655"
      unitRef="pure">0.0123</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019283_1_AdditionalIndexMember_5YR"
      decimals="INF"
      id="ixv-307656"
      unitRef="pure">-0.0077</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019283_1_AdditionalIndexMember_10YR"
      decimals="INF"
      id="ixv-307657"
      unitRef="pure">0.0083</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019283_2_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-307658"
      unitRef="pure">0.0189</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019283_2_BBIndexMember_5YR"
      decimals="INF"
      id="ixv-307659"
      unitRef="pure">-0.0029</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000019283_2_BBIndexMember_10YR"
      decimals="INF"
      id="ixv-307660"
      unitRef="pure">0.0140</oef:AvgAnnlRtrPct>
    <oef:UpdPerfInfoLocationTextBlock contextRef="C000019283_ClassMember" id="ixv-10765">&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="C000019283_ClassMember" id="ixv-10777">&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="C000019283_ClassMember" id="ixv-10781">&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="C000019283_ClassMember" id="ixv-10787">&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;$&lt;/span&gt;1,390,348,293&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;1,738&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;4,265,715&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;286&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="C000019283_InstantMember"
      decimals="0"
      id="ixv-307661"
      unitRef="usd">1390348293</us-gaap:AssetsNet>
    <oef:HoldingsCount
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      decimals="INF"
      id="ixv-307662"
      unitRef="holding">1738</oef:HoldingsCount>
    <oef:AdvisoryFeesPaidAmt
      contextRef="C000019283_ClassMember"
      decimals="0"
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      unitRef="usd">4265715</oef:AdvisoryFeesPaidAmt>
    <us-gaap:InvestmentCompanyPortfolioTurnover
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      decimals="INF"
      id="ixv-307664"
      unitRef="pure">2.86</us-gaap:InvestmentCompanyPortfolioTurnover>
    <oef:HoldingsTableTextBlock contextRef="C000019283_ClassMember" id="ixv-10862">
&#160;
COUPON DISTRIBUTION 
(% of Fund's net assets)


Zero coupon bonds

0.0

&#160;


1 - 1.99%

1.1

&#160;


2 - 2.99%

15.6

&#160;


3 - 3.99%

37.6

&#160;


4 - 4.99%

30.3

&#160;


5 - 5.99%

4.9

&#160;


6 - 6.99%

6.2

&#160;


7 - 7.99%

0.0

&#160;


8 - 8.99%

0.0

&#160;


17 - 17.99%

0.0

&#160;


18 - 18.99%

0.0

&#160;




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

58.3


U.S. Government Agency - Mortgage Securities

17.6


CMOs and Other Mortgage Related Securities

16.8


U.S. Government Agency Obligations

3.0


Options

0.2


Short-Term Investments and Net Other Assets (Liabilities)

4.1




ASSET ALLOCATION (% of Fund's net assets)


&#160;



&#160;

U.S. Treasury Obligations - 58.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

U.S. Government Agency - Mortgage Securities - 17.6


&#160;

CMOs and Other Mortgage Related Securities - 16.8


&#160;

U.S. Government Agency Obligations - 3.0


&#160;

Options - 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;

Short-Term Investments and Net Other Assets (Liabilities) - 4.1


&#160;






</oef:HoldingsTableTextBlock>
    <oef:PctOfNav
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      id="ixv-307665"
      unitRef="pure">0.000</oef:PctOfNav>
    <oef:PctOfNav
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      id="ixv-307666"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019283_CD_2_Member"
      decimals="INF"
      id="ixv-307667"
      unitRef="pure">0.156</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019283_CD_3_Member"
      decimals="INF"
      id="ixv-307668"
      unitRef="pure">0.376</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019283_CD_4_Member"
      decimals="INF"
      id="ixv-307669"
      unitRef="pure">0.303</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019283_CD_5_Member"
      decimals="INF"
      id="ixv-307670"
      unitRef="pure">0.049</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019283_CD_6_Member"
      decimals="INF"
      id="ixv-307671"
      unitRef="pure">0.062</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-307672"
      unitRef="pure">0.000</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-307673"
      unitRef="pure">0.000</oef:PctOfNav>
    <oef:PctOfNav
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      id="ixv-307674"
      unitRef="pure">0.000</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019283_CD_10_Member"
      decimals="INF"
      id="ixv-307675"
      unitRef="pure">0.000</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019283_AA_USTreasuryObligations_Member"
      decimals="INF"
      id="ixv-307676"
      unitRef="pure">0.583</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019283_AA_USGovernmentAgencyMortgageSecurities_Member"
      decimals="INF"
      id="ixv-307677"
      unitRef="pure">0.176</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019283_AA_CMOsandOtherMortgageRelatedSecurities_Member"
      decimals="INF"
      id="ixv-307678"
      unitRef="pure">0.168</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019283_AA_USGovernmentAgencyObligations_Member"
      decimals="INF"
      id="ixv-307679"
      unitRef="pure">0.030</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019283_AA_Options_Member"
      decimals="INF"
      id="ixv-307680"
      unitRef="pure">0.002</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019283_AA_ShortTermInvestmentsandNetOtherAssetsLiabilities_Member"
      decimals="INF"
      id="ixv-307681"
      unitRef="pure">0.041</oef:PctOfNav>
    <oef:LargestHoldingsTableTextBlock contextRef="C000019283_ClassMember" id="ixv-11086">TOP HOLDINGS(% of Fund's net assets)

&#160;

&#160;


US Treasury Notes

40.8


&#160;


US Treasury Bonds

17.5


&#160;


Freddie Mac Multifamily Structured pass-thru certificates

10.5


&#160;


Fannie Mae Mortgage pass-thru certificates

9.3


&#160;


Freddie Mac Gold Pool

8.2


&#160;


Ginnie Mae II Pool

3.0


&#160;


Fannie Mae Guaranteed REMIC

2.3


&#160;


Federal Home Loan Bank

1.4


&#160;


Federal Farm Credit Banks Funding Corp

1.2


&#160;


Ginnie Mae I Pool

1.2


&#160;


&#160;

95.4

&#160;



</oef:LargestHoldingsTableTextBlock>
    <oef:PctOfNav
      contextRef="C000019283_TH_0_Member"
      decimals="INF"
      id="ixv-307682"
      unitRef="pure">0.408</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019283_TH_1_Member"
      decimals="INF"
      id="ixv-307683"
      unitRef="pure">0.175</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019283_TH_2_Member"
      decimals="INF"
      id="ixv-307684"
      unitRef="pure">0.105</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019283_TH_3_Member"
      decimals="INF"
      id="ixv-307685"
      unitRef="pure">0.093</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019283_TH_4_Member"
      decimals="INF"
      id="ixv-307686"
      unitRef="pure">0.082</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019283_TH_5_Member"
      decimals="INF"
      id="ixv-307687"
      unitRef="pure">0.030</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019283_TH_6_Member"
      decimals="INF"
      id="ixv-307688"
      unitRef="pure">0.023</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019283_TH_7_Member"
      decimals="INF"
      id="ixv-307689"
      unitRef="pure">0.014</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019283_TH_8_Member"
      decimals="INF"
      id="ixv-307690"
      unitRef="pure">0.012</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019283_TH_9_Member"
      decimals="INF"
      id="ixv-307691"
      unitRef="pure">0.012</oef:PctOfNav>
    <oef:MaterialFundChngTextBlock contextRef="C000019283_ClassMember" id="ixv-11211">
&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 modified its principal investment risks 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="C000019283_ClassMember" id="ixv-11217">&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="C000019283_ClassMember" id="ixv-11219">&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="C000019283_ClassMember" id="ixv-11222">&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="C000019283_ClassMember" id="ixv-11226">&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:MaterialFundChngRisksChngTextBlock contextRef="C000019283_ClassMember" id="ixv-11237">
&lt;div style="text-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 risks 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:MaterialFundChngRisksChngTextBlock>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-11295">2026-08-31</dei:DocumentPeriodEndDate>
    <oef:MaterialFundChngNoticeTextBlock contextRef="C000205069_ClassMember" id="ixv-11299">This report describes changes to the Fund that occurred during the reporting period.</oef:MaterialFundChngNoticeTextBlock>
    <oef:FundName contextRef="C000205069_ClassMember" id="ixv-11310">Fidelity&#xae; Government Income Fund</oef:FundName>
    <oef:ClassName contextRef="C000205069_ClassMember" id="ixv-11313">Fidelity Advisor&#xae; Government Income Fund Class Z</oef:ClassName>
    <dei:TradingSymbol contextRef="C000205069_ClassMember" id="ixv-11317">FIKPX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000205069_ClassMember" id="ixv-11336">This annual shareholder report contains information about Fidelity&#xae; Government Income Fund for the period September 1, 2025 to August 31, 2026.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000205069_ClassMember" id="ixv-11338">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000205069_ClassMember" id="ixv-11343">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="C000205069_ClassMember" id="ixv-11345">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000205069_ClassMember" id="ixv-11348">1-877-208-0098</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000205069_ClassMember" id="ixv-11351">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000205069_ClassMember" id="ixv-11358">&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="C000205069_ClassMember"
      decimals="0"
      id="ixv-307692"
      unitRef="usd">36</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000205069_ClassMember"
      decimals="INF"
      id="ixv-307693"
      unitRef="pure">0.0036</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000205069_ClassMember" id="ixv-11401">&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, fast-growing government debt 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, an overweight in Ginnie Mae securities with coupons of 2.0% and 2.5% contributed to the fund's performance versus the Bloomberg 75% U.S. Government/25% U.S. Mortgage-Backed Securities Blended 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;An overweight in conventional 30-year mortgage pools with specified characteristics and coupons of 2.5% and higher boosted relative performance, as did an overweight in short-duration Freddie Mac multifamily securities.&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 underweight in conventional 30-year mortgage-backed securities with a coupon of 2% detracted versus the index.&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 longer duration (interest rate) positioning hurt relative performance.&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;Lastly, a small position in Treasury Inflation-Protected Securities detracted.&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="C000205069_ClassMember" id="ixv-11425">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

$11,027


$11,702


$11,520


$10,283


$10,041


$10,689


$10,947


$11,139



Bloomberg 75% U.S. Government/25% U.S. Mortgage-Backed Securities Blended Index


$10,000

$11,042


$11,740


$11,558


$10,350


$10,141


$10,790


$11,078


$11,264



Bloomberg U.S. Government Bond Index


$10,000

$11,132


$11,902


$11,662


$10,415


$10,206


$10,822


$11,087


$11,223



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="C000205069_LG_ClassMember_9YR" id="ixv-11444">&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="C000205069_ClassMember_AsOf_2018"
      decimals="0"
      id="ixv-307694"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000205069_ClassMember_AsOf_2019"
      decimals="0"
      id="ixv-307695"
      unitRef="usd">11027</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000205069_ClassMember_AsOf_2020"
      decimals="0"
      id="ixv-307696"
      unitRef="usd">11702</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000205069_ClassMember_AsOf_2021"
      decimals="0"
      id="ixv-307697"
      unitRef="usd">11520</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000205069_ClassMember_AsOf_2022"
      decimals="0"
      id="ixv-307698"
      unitRef="usd">10283</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000205069_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-307699"
      unitRef="usd">10041</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000205069_ClassMember_AsOf_2024"
      decimals="0"
      id="ixv-307700"
      unitRef="usd">10689</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000205069_ClassMember_AsOf_2025"
      decimals="0"
      id="ixv-307701"
      unitRef="usd">10947</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000205069_ClassMember_AsOf_2026"
      decimals="0"
      id="ixv-307702"
      unitRef="usd">11139</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000205069_LG_1_AdditionalIndexMember_9YR"
      id="ixv-11485">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg 75% U.S. Government/25% U.S. Mortgage-Backed Securities Blended Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000205069_1_AdditionalIndexMember_AsOf_2018"
      decimals="0"
      id="ixv-307703"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000205069_1_AdditionalIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-307704"
      unitRef="usd">11042</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000205069_1_AdditionalIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-307705"
      unitRef="usd">11740</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000205069_1_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-307706"
      unitRef="usd">11558</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000205069_1_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-307707"
      unitRef="usd">10350</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000205069_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-307708"
      unitRef="usd">10141</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000205069_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-307709"
      unitRef="usd">10790</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000205069_1_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-307710"
      unitRef="usd">11078</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000205069_1_AdditionalIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-307711"
      unitRef="usd">11264</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000205069_LG_2_AdditionalIndexMember_9YR"
      id="ixv-11526">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg U.S. Government Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000205069_2_AdditionalIndexMember_AsOf_2018"
      decimals="0"
      id="ixv-307712"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000205069_2_AdditionalIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-307713"
      unitRef="usd">11132</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000205069_2_AdditionalIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-307714"
      unitRef="usd">11902</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000205069_2_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-307715"
      unitRef="usd">11662</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000205069_2_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-307716"
      unitRef="usd">10415</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000205069_2_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-307717"
      unitRef="usd">10206</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000205069_2_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-307718"
      unitRef="usd">10822</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000205069_2_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-307719"
      unitRef="usd">11087</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000205069_2_AdditionalIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-307720"
      unitRef="usd">11223</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000205069_0_LG_BBIndexMember_9YR"
      id="ixv-11567">&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="C000205069_0_BBIndexMember_AsOf_2018"
      decimals="0"
      id="ixv-307721"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000205069_0_BBIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-307722"
      unitRef="usd">11086</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000205069_0_BBIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-307723"
      unitRef="usd">11804</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000205069_0_BBIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-307724"
      unitRef="usd">11794</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000205069_0_BBIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-307725"
      unitRef="usd">10436</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000205069_0_BBIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-307726"
      unitRef="usd">10311</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000205069_0_BBIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-307727"
      unitRef="usd">11064</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000205069_0_BBIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-307728"
      unitRef="usd">11411</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000205069_0_BBIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-307729"
      unitRef="usd">11626</oef:AccmVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000205069_ClassMember" id="ixv-11653">AVERAGE ANNUAL TOTAL RETURNS:

&#160;

1 Year

5 Year

Life of Fund&#160;A


Class Z

1.76%

-0.67%

1.37%


Bloomberg 75% U.S. Government/25% U.S. Mortgage-Backed Securities Blended Index

1.67%


-0.51%


1.51%


Bloomberg U.S. Government Bond Index

1.23%


-0.77%


1.47%


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="C000205069_NoLoadClassMember_1YR"
      decimals="INF"
      id="ixv-307730"
      unitRef="pure">0.0176</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000205069_NoLoadClassMember_5YR"
      decimals="INF"
      id="ixv-307731"
      unitRef="pure">-0.0067</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000205069_NoLoadClassMember_2025-09-01_2026-08-31"
      decimals="INF"
      id="ixv-307732"
      unitRef="pure">0.0137</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000205069_0_AdditionalIndexMember_1YR"
      decimals="INF"
      id="ixv-307733"
      unitRef="pure">0.0167</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000205069_0_AdditionalIndexMember_5YR"
      decimals="INF"
      id="ixv-307734"
      unitRef="pure">-0.0051</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000205069_0_AdditionalIndexMember_LOC"
      decimals="INF"
      id="ixv-307735"
      unitRef="pure">0.0151</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000205069_1_AdditionalIndexMember_1YR"
      decimals="INF"
      id="ixv-307736"
      unitRef="pure">0.0123</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000205069_1_AdditionalIndexMember_5YR"
      decimals="INF"
      id="ixv-307737"
      unitRef="pure">-0.0077</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000205069_1_AdditionalIndexMember_LOC"
      decimals="INF"
      id="ixv-307738"
      unitRef="pure">0.0147</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000205069_2_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-307739"
      unitRef="pure">0.0189</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000205069_2_BBIndexMember_5YR"
      decimals="INF"
      id="ixv-307740"
      unitRef="pure">-0.0029</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000205069_2_BBIndexMember_LOC"
      decimals="INF"
      id="ixv-307741"
      unitRef="pure">0.0192</oef:AvgAnnlRtrPct>
    <oef:PerfInceptionDate
      contextRef="C000205069_Perf_2018-10-02_ClassMember"
      id="ixv-11741">2018-10-02</oef:PerfInceptionDate>
    <oef:UpdPerfInfoLocationTextBlock contextRef="C000205069_ClassMember" id="ixv-11751">&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="C000205069_ClassMember" id="ixv-11763">&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="C000205069_ClassMember" id="ixv-11767">&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="C000205069_ClassMember" id="ixv-11773">&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;$&lt;/span&gt;1,390,348,293&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;1,738&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;4,265,715&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;286&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="C000205069_InstantMember"
      decimals="0"
      id="ixv-307742"
      unitRef="usd">1390348293</us-gaap:AssetsNet>
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      decimals="INF"
      id="ixv-307743"
      unitRef="holding">1738</oef:HoldingsCount>
    <oef:AdvisoryFeesPaidAmt
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      decimals="0"
      id="ixv-307744"
      unitRef="usd">4265715</oef:AdvisoryFeesPaidAmt>
    <us-gaap:InvestmentCompanyPortfolioTurnover
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      decimals="INF"
      id="ixv-307745"
      unitRef="pure">2.86</us-gaap:InvestmentCompanyPortfolioTurnover>
    <oef:HoldingsTableTextBlock contextRef="C000205069_ClassMember" id="ixv-11848">
&#160;
COUPON DISTRIBUTION 
(% of Fund's net assets)


Zero coupon bonds

0.0

&#160;


1 - 1.99%

1.1

&#160;


2 - 2.99%

15.6

&#160;


3 - 3.99%

37.6

&#160;


4 - 4.99%

30.3

&#160;


5 - 5.99%

4.9

&#160;


6 - 6.99%

6.2

&#160;


7 - 7.99%

0.0

&#160;


8 - 8.99%

0.0

&#160;


17 - 17.99%

0.0

&#160;


18 - 18.99%

0.0

&#160;




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

58.3


U.S. Government Agency - Mortgage Securities

17.6


CMOs and Other Mortgage Related Securities

16.8


U.S. Government Agency Obligations

3.0


Options

0.2


Short-Term Investments and Net Other Assets (Liabilities)

4.1




ASSET ALLOCATION (% of Fund's net assets)


&#160;



&#160;

U.S. Treasury Obligations - 58.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

U.S. Government Agency - Mortgage Securities - 17.6


&#160;

CMOs and Other Mortgage Related Securities - 16.8


&#160;

U.S. Government Agency Obligations - 3.0


&#160;

Options - 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;

Short-Term Investments and Net Other Assets (Liabilities) - 4.1


&#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
      contextRef="C000205069_AA_USTreasuryObligations_Member"
      decimals="INF"
      id="ixv-307757"
      unitRef="pure">0.583</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000205069_AA_USGovernmentAgencyMortgageSecurities_Member"
      decimals="INF"
      id="ixv-307758"
      unitRef="pure">0.176</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000205069_AA_CMOsandOtherMortgageRelatedSecurities_Member"
      decimals="INF"
      id="ixv-307759"
      unitRef="pure">0.168</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000205069_AA_USGovernmentAgencyObligations_Member"
      decimals="INF"
      id="ixv-307760"
      unitRef="pure">0.030</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000205069_AA_Options_Member"
      decimals="INF"
      id="ixv-307761"
      unitRef="pure">0.002</oef:PctOfNav>
    <oef:PctOfNav
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      unitRef="pure">0.041</oef:PctOfNav>
    <oef:LargestHoldingsTableTextBlock contextRef="C000205069_ClassMember" id="ixv-12072">TOP HOLDINGS(% of Fund's net assets)

&#160;

&#160;


US Treasury Notes

40.8


&#160;


US Treasury Bonds

17.5


&#160;


Freddie Mac Multifamily Structured pass-thru certificates

10.5


&#160;


Fannie Mae Mortgage pass-thru certificates

9.3


&#160;


Freddie Mac Gold Pool

8.2


&#160;


Ginnie Mae II Pool

3.0


&#160;


Fannie Mae Guaranteed REMIC

2.3


&#160;


Federal Home Loan Bank

1.4


&#160;


Federal Farm Credit Banks Funding Corp

1.2


&#160;


Ginnie Mae I Pool

1.2


&#160;


&#160;

95.4

&#160;



</oef:LargestHoldingsTableTextBlock>
    <oef:PctOfNav
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      id="ixv-307763"
      unitRef="pure">0.408</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-307764"
      unitRef="pure">0.175</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-307765"
      unitRef="pure">0.105</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000205069_TH_3_Member"
      decimals="INF"
      id="ixv-307766"
      unitRef="pure">0.093</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000205069_TH_4_Member"
      decimals="INF"
      id="ixv-307767"
      unitRef="pure">0.082</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000205069_TH_5_Member"
      decimals="INF"
      id="ixv-307768"
      unitRef="pure">0.030</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000205069_TH_6_Member"
      decimals="INF"
      id="ixv-307769"
      unitRef="pure">0.023</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000205069_TH_7_Member"
      decimals="INF"
      id="ixv-307770"
      unitRef="pure">0.014</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000205069_TH_8_Member"
      decimals="INF"
      id="ixv-307771"
      unitRef="pure">0.012</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000205069_TH_9_Member"
      decimals="INF"
      id="ixv-307772"
      unitRef="pure">0.012</oef:PctOfNav>
    <oef:MaterialFundChngTextBlock contextRef="C000205069_ClassMember" id="ixv-12197">
&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 modified its principal investment risks 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="C000205069_ClassMember" id="ixv-12203">&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="C000205069_ClassMember" id="ixv-12205">&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="C000205069_ClassMember" id="ixv-12208">&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="C000205069_ClassMember" id="ixv-12212">&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:MaterialFundChngRisksChngTextBlock contextRef="C000205069_ClassMember" id="ixv-12223">
&lt;div style="text-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 risks 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:MaterialFundChngRisksChngTextBlock>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-12281">2026-08-31</dei:DocumentPeriodEndDate>
    <oef:MaterialFundChngNoticeTextBlock contextRef="C000038101_ClassMember" id="ixv-12285">This report describes changes to the Fund that occurred during the reporting period.</oef:MaterialFundChngNoticeTextBlock>
    <oef:FundName contextRef="C000038101_ClassMember" id="ixv-12296">Fidelity&#xae; Government Income Fund</oef:FundName>
    <oef:ClassName contextRef="C000038101_ClassMember" id="ixv-12299">Fidelity Advisor&#xae; Government Income Fund Class M</oef:ClassName>
    <dei:TradingSymbol contextRef="C000038101_ClassMember" id="ixv-12303">FVITX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000038101_ClassMember" id="ixv-12322">This annual shareholder report contains information about Fidelity&#xae; Government Income Fund for the period September 1, 2025 to August 31, 2026.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000038101_ClassMember" id="ixv-12324">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000038101_ClassMember" id="ixv-12329">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="C000038101_ClassMember" id="ixv-12331">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000038101_ClassMember" id="ixv-12334">1-877-208-0098</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000038101_ClassMember" id="ixv-12337">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000038101_ClassMember" id="ixv-12344">&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;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;0.76&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="C000038101_ClassMember"
      decimals="0"
      id="ixv-307773"
      unitRef="usd">76</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000038101_ClassMember"
      decimals="INF"
      id="ixv-307774"
      unitRef="pure">0.0076</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000038101_ClassMember" id="ixv-12387">&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, fast-growing government debt 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, an overweight in Ginnie Mae securities with coupons of 2.0% and 2.5% contributed to the fund's performance versus the Bloomberg 75% U.S. Government/25% U.S. Mortgage-Backed Securities Blended 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;An overweight in conventional 30-year mortgage pools with specified characteristics and coupons of 2.5% and higher boosted relative performance, as did an overweight in short-duration Freddie Mac multifamily securities.&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 underweight in conventional 30-year mortgage-backed securities with a coupon of 2% detracted versus the index.&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 longer duration (interest rate) positioning hurt relative performance.&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;Lastly, a small position in Treasury Inflation-Protected Securities detracted.&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="C000038101_ClassMember" id="ixv-12411">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

$9,530


$9,351


$10,201


$10,772


$10,565


$9,402


$9,134


$9,696


$9,889


$10,023



Bloomberg 75% U.S. Government/25% U.S. Mortgage-Backed Securities Blended Index


$10,000

$9,957


$9,832


$10,765


$11,447


$11,269


$10,091


$9,888


$10,520


$10,801


$10,982



Bloomberg U.S. Government Bond Index


$10,000

$9,916


$9,767


$10,774


$11,519


$11,287


$10,080


$9,878


$10,474


$10,730


$10,862



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="C000038101_LG_ClassMember_11YR" id="ixv-12432">&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="C000038101_ClassMember_AsOf_2016"
      decimals="0"
      id="ixv-307775"
      unitRef="usd">9600</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038101_ClassMember_AsOf_2017"
      decimals="0"
      id="ixv-307776"
      unitRef="usd">9530</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038101_ClassMember_AsOf_2018"
      decimals="0"
      id="ixv-307777"
      unitRef="usd">9351</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038101_ClassMember_AsOf_2019"
      decimals="0"
      id="ixv-307778"
      unitRef="usd">10201</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038101_ClassMember_AsOf_2020"
      decimals="0"
      id="ixv-307779"
      unitRef="usd">10772</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038101_ClassMember_AsOf_2021"
      decimals="0"
      id="ixv-307780"
      unitRef="usd">10565</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038101_ClassMember_AsOf_2022"
      decimals="0"
      id="ixv-307781"
      unitRef="usd">9402</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038101_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-307782"
      unitRef="usd">9134</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038101_ClassMember_AsOf_2024"
      decimals="0"
      id="ixv-307783"
      unitRef="usd">9696</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038101_ClassMember_AsOf_2025"
      decimals="0"
      id="ixv-307784"
      unitRef="usd">9889</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038101_ClassMember_AsOf_2026"
      decimals="0"
      id="ixv-307785"
      unitRef="usd">10023</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000038101_LG_1_AdditionalIndexMember_11YR"
      id="ixv-12481">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg 75% U.S. Government/25% U.S. Mortgage-Backed Securities Blended Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000038101_1_AdditionalIndexMember_AsOf_2016"
      decimals="0"
      id="ixv-307786"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038101_1_AdditionalIndexMember_AsOf_2017"
      decimals="0"
      id="ixv-307787"
      unitRef="usd">9957</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038101_1_AdditionalIndexMember_AsOf_2018"
      decimals="0"
      id="ixv-307788"
      unitRef="usd">9832</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038101_1_AdditionalIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-307789"
      unitRef="usd">10765</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038101_1_AdditionalIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-307790"
      unitRef="usd">11447</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038101_1_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-307791"
      unitRef="usd">11269</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038101_1_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-307792"
      unitRef="usd">10091</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038101_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-307793"
      unitRef="usd">9888</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038101_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-307794"
      unitRef="usd">10520</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038101_1_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-307795"
      unitRef="usd">10801</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038101_1_AdditionalIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-307796"
      unitRef="usd">10982</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000038101_LG_2_AdditionalIndexMember_11YR"
      id="ixv-12530">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg U.S. Government Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000038101_2_AdditionalIndexMember_AsOf_2016"
      decimals="0"
      id="ixv-307797"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038101_2_AdditionalIndexMember_AsOf_2017"
      decimals="0"
      id="ixv-307798"
      unitRef="usd">9916</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038101_2_AdditionalIndexMember_AsOf_2018"
      decimals="0"
      id="ixv-307799"
      unitRef="usd">9767</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038101_2_AdditionalIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-307800"
      unitRef="usd">10774</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038101_2_AdditionalIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-307801"
      unitRef="usd">11519</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038101_2_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-307802"
      unitRef="usd">11287</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038101_2_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-307803"
      unitRef="usd">10080</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038101_2_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-307804"
      unitRef="usd">9878</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038101_2_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-307805"
      unitRef="usd">10474</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038101_2_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-307806"
      unitRef="usd">10730</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038101_2_AdditionalIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-307807"
      unitRef="usd">10862</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000038101_0_LG_BBIndexMember_11YR"
      id="ixv-12579">&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="C000038101_0_BBIndexMember_AsOf_2016"
      decimals="0"
      id="ixv-307808"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038101_0_BBIndexMember_AsOf_2017"
      decimals="0"
      id="ixv-307809"
      unitRef="usd">10049</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038101_0_BBIndexMember_AsOf_2018"
      decimals="0"
      id="ixv-307810"
      unitRef="usd">9944</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038101_0_BBIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-307811"
      unitRef="usd">10955</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038101_0_BBIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-307812"
      unitRef="usd">11665</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038101_0_BBIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-307813"
      unitRef="usd">11655</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038101_0_BBIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-307814"
      unitRef="usd">10313</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038101_0_BBIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-307815"
      unitRef="usd">10189</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038101_0_BBIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-307816"
      unitRef="usd">10933</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038101_0_BBIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-307817"
      unitRef="usd">11276</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038101_0_BBIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-307818"
      unitRef="usd">11489</oef:AccmVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000038101_ClassMember" id="ixv-12679">AVERAGE ANNUAL TOTAL RETURNS:

&#160;

1 Year

5 Year

10 Year


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

-2.70%

-1.85%


0.02%


Class M (without 4.00% sales charge)

1.35%

-1.05%

0.43%


Bloomberg 75% U.S. Government/25% U.S. Mortgage-Backed Securities Blended Index

1.67%


-0.51%


0.94%


Bloomberg U.S. Government Bond Index

1.23%


-0.77%


0.83%


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="C000038101_ClassMember_1YR"
      decimals="INF"
      id="ixv-307819"
      unitRef="pure">-0.0270</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000038101_ClassMember_5YR"
      decimals="INF"
      id="ixv-307820"
      unitRef="pure">-0.0185</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000038101_ClassMember_10YR"
      decimals="INF"
      id="ixv-307821"
      unitRef="pure">0.0002</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000038101_NoLoadClassMember_1YR"
      decimals="INF"
      id="ixv-307822"
      unitRef="pure">0.0135</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000038101_NoLoadClassMember_5YR"
      decimals="INF"
      id="ixv-307823"
      unitRef="pure">-0.0105</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000038101_NoLoadClassMember_10YR"
      decimals="INF"
      id="ixv-307824"
      unitRef="pure">0.0043</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000038101_0_AdditionalIndexMember_1YR"
      decimals="INF"
      id="ixv-307825"
      unitRef="pure">0.0167</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000038101_0_AdditionalIndexMember_5YR"
      decimals="INF"
      id="ixv-307826"
      unitRef="pure">-0.0051</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000038101_0_AdditionalIndexMember_10YR"
      decimals="INF"
      id="ixv-307827"
      unitRef="pure">0.0094</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000038101_1_AdditionalIndexMember_1YR"
      decimals="INF"
      id="ixv-307828"
      unitRef="pure">0.0123</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000038101_1_AdditionalIndexMember_5YR"
      decimals="INF"
      id="ixv-307829"
      unitRef="pure">-0.0077</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000038101_1_AdditionalIndexMember_10YR"
      decimals="INF"
      id="ixv-307830"
      unitRef="pure">0.0083</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000038101_2_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-307831"
      unitRef="pure">0.0189</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000038101_2_BBIndexMember_5YR"
      decimals="INF"
      id="ixv-307832"
      unitRef="pure">-0.0029</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000038101_2_BBIndexMember_10YR"
      decimals="INF"
      id="ixv-307833"
      unitRef="pure">0.0140</oef:AvgAnnlRtrPct>
    <oef:UpdPerfInfoLocationTextBlock contextRef="C000038101_ClassMember" id="ixv-12785">&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="C000038101_ClassMember" id="ixv-12797">&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="C000038101_ClassMember" id="ixv-12801">&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="C000038101_ClassMember" id="ixv-12807">&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;$&lt;/span&gt;1,390,348,293&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;1,738&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;4,265,715&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;286&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="C000038101_InstantMember"
      decimals="0"
      id="ixv-307834"
      unitRef="usd">1390348293</us-gaap:AssetsNet>
    <oef:HoldingsCount
      contextRef="C000038101_InstantMember"
      decimals="INF"
      id="ixv-307835"
      unitRef="holding">1738</oef:HoldingsCount>
    <oef:AdvisoryFeesPaidAmt
      contextRef="C000038101_ClassMember"
      decimals="0"
      id="ixv-307836"
      unitRef="usd">4265715</oef:AdvisoryFeesPaidAmt>
    <us-gaap:InvestmentCompanyPortfolioTurnover
      contextRef="C000038101_ClassMember"
      decimals="INF"
      id="ixv-307837"
      unitRef="pure">2.86</us-gaap:InvestmentCompanyPortfolioTurnover>
    <oef:HoldingsTableTextBlock contextRef="C000038101_ClassMember" id="ixv-12882">
&#160;
COUPON DISTRIBUTION 
(% of Fund's net assets)


Zero coupon bonds

0.0

&#160;


1 - 1.99%

1.1

&#160;


2 - 2.99%

15.6

&#160;


3 - 3.99%

37.6

&#160;


4 - 4.99%

30.3

&#160;


5 - 5.99%

4.9

&#160;


6 - 6.99%

6.2

&#160;


7 - 7.99%

0.0

&#160;


8 - 8.99%

0.0

&#160;


17 - 17.99%

0.0

&#160;


18 - 18.99%

0.0

&#160;




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

58.3


U.S. Government Agency - Mortgage Securities

17.6


CMOs and Other Mortgage Related Securities

16.8


U.S. Government Agency Obligations

3.0


Options

0.2


Short-Term Investments and Net Other Assets (Liabilities)

4.1




ASSET ALLOCATION (% of Fund's net assets)


&#160;



&#160;

U.S. Treasury Obligations - 58.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

U.S. Government Agency - Mortgage Securities - 17.6


&#160;

CMOs and Other Mortgage Related Securities - 16.8


&#160;

U.S. Government Agency Obligations - 3.0


&#160;

Options - 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;

Short-Term Investments and Net Other Assets (Liabilities) - 4.1


&#160;






</oef:HoldingsTableTextBlock>
    <oef:PctOfNav
      contextRef="C000038101_CD_0_Member"
      decimals="INF"
      id="ixv-307838"
      unitRef="pure">0.000</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038101_CD_1_Member"
      decimals="INF"
      id="ixv-307839"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038101_CD_2_Member"
      decimals="INF"
      id="ixv-307840"
      unitRef="pure">0.156</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038101_CD_3_Member"
      decimals="INF"
      id="ixv-307841"
      unitRef="pure">0.376</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038101_CD_4_Member"
      decimals="INF"
      id="ixv-307842"
      unitRef="pure">0.303</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038101_CD_5_Member"
      decimals="INF"
      id="ixv-307843"
      unitRef="pure">0.049</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038101_CD_6_Member"
      decimals="INF"
      id="ixv-307844"
      unitRef="pure">0.062</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038101_CD_7_Member"
      decimals="INF"
      id="ixv-307845"
      unitRef="pure">0.000</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038101_CD_8_Member"
      decimals="INF"
      id="ixv-307846"
      unitRef="pure">0.000</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038101_CD_9_Member"
      decimals="INF"
      id="ixv-307847"
      unitRef="pure">0.000</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038101_CD_10_Member"
      decimals="INF"
      id="ixv-307848"
      unitRef="pure">0.000</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038101_AA_USTreasuryObligations_Member"
      decimals="INF"
      id="ixv-307849"
      unitRef="pure">0.583</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038101_AA_USGovernmentAgencyMortgageSecurities_Member"
      decimals="INF"
      id="ixv-307850"
      unitRef="pure">0.176</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038101_AA_CMOsandOtherMortgageRelatedSecurities_Member"
      decimals="INF"
      id="ixv-307851"
      unitRef="pure">0.168</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038101_AA_USGovernmentAgencyObligations_Member"
      decimals="INF"
      id="ixv-307852"
      unitRef="pure">0.030</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038101_AA_Options_Member"
      decimals="INF"
      id="ixv-307853"
      unitRef="pure">0.002</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038101_AA_ShortTermInvestmentsandNetOtherAssetsLiabilities_Member"
      decimals="INF"
      id="ixv-307854"
      unitRef="pure">0.041</oef:PctOfNav>
    <oef:LargestHoldingsTableTextBlock contextRef="C000038101_ClassMember" id="ixv-13106">TOP HOLDINGS(% of Fund's net assets)

&#160;

&#160;


US Treasury Notes

40.8


&#160;


US Treasury Bonds

17.5


&#160;


Freddie Mac Multifamily Structured pass-thru certificates

10.5


&#160;


Fannie Mae Mortgage pass-thru certificates

9.3


&#160;


Freddie Mac Gold Pool

8.2


&#160;


Ginnie Mae II Pool

3.0


&#160;


Fannie Mae Guaranteed REMIC

2.3


&#160;


Federal Home Loan Bank

1.4


&#160;


Federal Farm Credit Banks Funding Corp

1.2


&#160;


Ginnie Mae I Pool

1.2


&#160;


&#160;

95.4

&#160;



</oef:LargestHoldingsTableTextBlock>
    <oef:PctOfNav
      contextRef="C000038101_TH_0_Member"
      decimals="INF"
      id="ixv-307855"
      unitRef="pure">0.408</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038101_TH_1_Member"
      decimals="INF"
      id="ixv-307856"
      unitRef="pure">0.175</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038101_TH_2_Member"
      decimals="INF"
      id="ixv-307857"
      unitRef="pure">0.105</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038101_TH_3_Member"
      decimals="INF"
      id="ixv-307858"
      unitRef="pure">0.093</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038101_TH_4_Member"
      decimals="INF"
      id="ixv-307859"
      unitRef="pure">0.082</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038101_TH_5_Member"
      decimals="INF"
      id="ixv-307860"
      unitRef="pure">0.030</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038101_TH_6_Member"
      decimals="INF"
      id="ixv-307861"
      unitRef="pure">0.023</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038101_TH_7_Member"
      decimals="INF"
      id="ixv-307862"
      unitRef="pure">0.014</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038101_TH_8_Member"
      decimals="INF"
      id="ixv-307863"
      unitRef="pure">0.012</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038101_TH_9_Member"
      decimals="INF"
      id="ixv-307864"
      unitRef="pure">0.012</oef:PctOfNav>
    <oef:MaterialFundChngTextBlock contextRef="C000038101_ClassMember" id="ixv-13231">
&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 modified its principal investment risks 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="C000038101_ClassMember" id="ixv-13237">&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="C000038101_ClassMember" id="ixv-13239">&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="C000038101_ClassMember" id="ixv-13242">&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="C000038101_ClassMember" id="ixv-13246">&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:MaterialFundChngRisksChngTextBlock contextRef="C000038101_ClassMember" id="ixv-13257">
&lt;div style="text-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 risks 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:MaterialFundChngRisksChngTextBlock>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-13315">2026-08-31</dei:DocumentPeriodEndDate>
    <oef:MaterialFundChngNoticeTextBlock contextRef="C000038102_ClassMember" id="ixv-13319">This report describes changes to the Fund that occurred during the reporting period.</oef:MaterialFundChngNoticeTextBlock>
    <oef:FundName contextRef="C000038102_ClassMember" id="ixv-13330">Fidelity&#xae; Government Income Fund</oef:FundName>
    <oef:ClassName contextRef="C000038102_ClassMember" id="ixv-13333">Fidelity Advisor&#xae; Government Income Fund Class I</oef:ClassName>
    <dei:TradingSymbol contextRef="C000038102_ClassMember" id="ixv-13337">FVIIX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000038102_ClassMember" id="ixv-13356">This annual shareholder report contains information about Fidelity&#xae; Government Income Fund for the period September 1, 2025 to August 31, 2026.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000038102_ClassMember" id="ixv-13358">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000038102_ClassMember" id="ixv-13363">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="C000038102_ClassMember" id="ixv-13365">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000038102_ClassMember" id="ixv-13368">1-877-208-0098</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000038102_ClassMember" id="ixv-13371">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000038102_ClassMember" id="ixv-13378">&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;0.49&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="C000038102_ClassMember"
      decimals="0"
      id="ixv-307865"
      unitRef="usd">50</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000038102_ClassMember"
      decimals="INF"
      id="ixv-307866"
      unitRef="pure">0.0049</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000038102_ClassMember" id="ixv-13421">&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, fast-growing government debt 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, an overweight in Ginnie Mae securities with coupons of 2.0% and 2.5% contributed to the fund's performance versus the Bloomberg 75% U.S. Government/25% U.S. Mortgage-Backed Securities Blended 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;An overweight in conventional 30-year mortgage pools with specified characteristics and coupons of 2.5% and higher boosted relative performance, as did an overweight in short-duration Freddie Mac multifamily securities.&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 underweight in conventional 30-year mortgage-backed securities with a coupon of 2% detracted versus the index.&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 longer duration (interest rate) positioning hurt relative performance.&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;Lastly, a small position in Treasury Inflation-Protected Securities detracted.&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="C000038102_ClassMember" id="ixv-13445">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

$9,954


$9,793


$10,712


$11,343


$11,162


$9,951


$9,693


$10,316


$10,550


$10,721



Bloomberg 75% U.S. Government/25% U.S. Mortgage-Backed Securities Blended Index


$10,000

$9,957


$9,832


$10,765


$11,447


$11,269


$10,091


$9,888


$10,520


$10,801


$10,982



Bloomberg U.S. Government Bond Index


$10,000

$9,916


$9,767


$10,774


$11,519


$11,287


$10,080


$9,878


$10,474


$10,730


$10,862



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="C000038102_LG_ClassMember_11YR" id="ixv-13464">&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="C000038102_ClassMember_AsOf_2016"
      decimals="0"
      id="ixv-307867"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038102_ClassMember_AsOf_2017"
      decimals="0"
      id="ixv-307868"
      unitRef="usd">9954</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038102_ClassMember_AsOf_2018"
      decimals="0"
      id="ixv-307869"
      unitRef="usd">9793</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038102_ClassMember_AsOf_2019"
      decimals="0"
      id="ixv-307870"
      unitRef="usd">10712</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038102_ClassMember_AsOf_2020"
      decimals="0"
      id="ixv-307871"
      unitRef="usd">11343</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038102_ClassMember_AsOf_2021"
      decimals="0"
      id="ixv-307872"
      unitRef="usd">11162</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038102_ClassMember_AsOf_2022"
      decimals="0"
      id="ixv-307873"
      unitRef="usd">9951</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038102_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-307874"
      unitRef="usd">9693</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038102_ClassMember_AsOf_2024"
      decimals="0"
      id="ixv-307875"
      unitRef="usd">10316</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038102_ClassMember_AsOf_2025"
      decimals="0"
      id="ixv-307876"
      unitRef="usd">10550</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038102_ClassMember_AsOf_2026"
      decimals="0"
      id="ixv-307877"
      unitRef="usd">10721</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000038102_LG_1_AdditionalIndexMember_11YR"
      id="ixv-13513">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg 75% U.S. Government/25% U.S. Mortgage-Backed Securities Blended Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000038102_1_AdditionalIndexMember_AsOf_2016"
      decimals="0"
      id="ixv-307878"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038102_1_AdditionalIndexMember_AsOf_2017"
      decimals="0"
      id="ixv-307879"
      unitRef="usd">9957</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038102_1_AdditionalIndexMember_AsOf_2018"
      decimals="0"
      id="ixv-307880"
      unitRef="usd">9832</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038102_1_AdditionalIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-307881"
      unitRef="usd">10765</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038102_1_AdditionalIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-307882"
      unitRef="usd">11447</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038102_1_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-307883"
      unitRef="usd">11269</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038102_1_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-307884"
      unitRef="usd">10091</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038102_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-307885"
      unitRef="usd">9888</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038102_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-307886"
      unitRef="usd">10520</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038102_1_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-307887"
      unitRef="usd">10801</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038102_1_AdditionalIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-307888"
      unitRef="usd">10982</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000038102_LG_2_AdditionalIndexMember_11YR"
      id="ixv-13562">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg U.S. Government Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000038102_2_AdditionalIndexMember_AsOf_2016"
      decimals="0"
      id="ixv-307889"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038102_2_AdditionalIndexMember_AsOf_2017"
      decimals="0"
      id="ixv-307890"
      unitRef="usd">9916</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038102_2_AdditionalIndexMember_AsOf_2018"
      decimals="0"
      id="ixv-307891"
      unitRef="usd">9767</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038102_2_AdditionalIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-307892"
      unitRef="usd">10774</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038102_2_AdditionalIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-307893"
      unitRef="usd">11519</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038102_2_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-307894"
      unitRef="usd">11287</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038102_2_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-307895"
      unitRef="usd">10080</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038102_2_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-307896"
      unitRef="usd">9878</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038102_2_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-307897"
      unitRef="usd">10474</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038102_2_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-307898"
      unitRef="usd">10730</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038102_2_AdditionalIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-307899"
      unitRef="usd">10862</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000038102_0_LG_BBIndexMember_11YR"
      id="ixv-13611">&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="C000038102_0_BBIndexMember_AsOf_2016"
      decimals="0"
      id="ixv-307900"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038102_0_BBIndexMember_AsOf_2017"
      decimals="0"
      id="ixv-307901"
      unitRef="usd">10049</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038102_0_BBIndexMember_AsOf_2018"
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      unitRef="usd">9944</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038102_0_BBIndexMember_AsOf_2019"
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      decimals="0"
      id="ixv-307904"
      unitRef="usd">11665</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038102_0_BBIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-307905"
      unitRef="usd">11655</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038102_0_BBIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-307906"
      unitRef="usd">10313</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038102_0_BBIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-307907"
      unitRef="usd">10189</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038102_0_BBIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-307908"
      unitRef="usd">10933</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038102_0_BBIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-307909"
      unitRef="usd">11276</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038102_0_BBIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-307910"
      unitRef="usd">11489</oef:AccmVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000038102_ClassMember" id="ixv-13711">AVERAGE ANNUAL TOTAL RETURNS:

&#160;

1 Year

5 Year

10 Year


Class I

1.62%

-0.80%

0.70%


Bloomberg 75% U.S. Government/25% U.S. Mortgage-Backed Securities Blended Index

1.67%


-0.51%


0.94%


Bloomberg U.S. Government Bond Index

1.23%


-0.77%


0.83%


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="C000038102_NoLoadClassMember_1YR"
      decimals="INF"
      id="ixv-307911"
      unitRef="pure">0.0162</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000038102_NoLoadClassMember_5YR"
      decimals="INF"
      id="ixv-307912"
      unitRef="pure">-0.0080</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000038102_NoLoadClassMember_10YR"
      decimals="INF"
      id="ixv-307913"
      unitRef="pure">0.0070</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000038102_0_AdditionalIndexMember_1YR"
      decimals="INF"
      id="ixv-307914"
      unitRef="pure">0.0167</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000038102_0_AdditionalIndexMember_5YR"
      decimals="INF"
      id="ixv-307915"
      unitRef="pure">-0.0051</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000038102_0_AdditionalIndexMember_10YR"
      decimals="INF"
      id="ixv-307916"
      unitRef="pure">0.0094</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000038102_1_AdditionalIndexMember_1YR"
      decimals="INF"
      id="ixv-307917"
      unitRef="pure">0.0123</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000038102_1_AdditionalIndexMember_5YR"
      decimals="INF"
      id="ixv-307918"
      unitRef="pure">-0.0077</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000038102_1_AdditionalIndexMember_10YR"
      decimals="INF"
      id="ixv-307919"
      unitRef="pure">0.0083</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000038102_2_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-307920"
      unitRef="pure">0.0189</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000038102_2_BBIndexMember_5YR"
      decimals="INF"
      id="ixv-307921"
      unitRef="pure">-0.0029</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000038102_2_BBIndexMember_10YR"
      decimals="INF"
      id="ixv-307922"
      unitRef="pure">0.0140</oef:AvgAnnlRtrPct>
    <oef:UpdPerfInfoLocationTextBlock contextRef="C000038102_ClassMember" id="ixv-13800">&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="C000038102_ClassMember" id="ixv-13812">&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="C000038102_ClassMember" id="ixv-13816">&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="C000038102_ClassMember" id="ixv-13822">&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;$&lt;/span&gt;1,390,348,293&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;1,738&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;4,265,715&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;286&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="C000038102_InstantMember"
      decimals="0"
      id="ixv-307923"
      unitRef="usd">1390348293</us-gaap:AssetsNet>
    <oef:HoldingsCount
      contextRef="C000038102_InstantMember"
      decimals="INF"
      id="ixv-307924"
      unitRef="holding">1738</oef:HoldingsCount>
    <oef:AdvisoryFeesPaidAmt
      contextRef="C000038102_ClassMember"
      decimals="0"
      id="ixv-307925"
      unitRef="usd">4265715</oef:AdvisoryFeesPaidAmt>
    <us-gaap:InvestmentCompanyPortfolioTurnover
      contextRef="C000038102_ClassMember"
      decimals="INF"
      id="ixv-307926"
      unitRef="pure">2.86</us-gaap:InvestmentCompanyPortfolioTurnover>
    <oef:HoldingsTableTextBlock contextRef="C000038102_ClassMember" id="ixv-13897">
&#160;
COUPON DISTRIBUTION 
(% of Fund's net assets)


Zero coupon bonds

0.0

&#160;


1 - 1.99%

1.1

&#160;


2 - 2.99%

15.6

&#160;


3 - 3.99%

37.6

&#160;


4 - 4.99%

30.3

&#160;


5 - 5.99%

4.9

&#160;


6 - 6.99%

6.2

&#160;


7 - 7.99%

0.0

&#160;


8 - 8.99%

0.0

&#160;


17 - 17.99%

0.0

&#160;


18 - 18.99%

0.0

&#160;




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

58.3


U.S. Government Agency - Mortgage Securities

17.6


CMOs and Other Mortgage Related Securities

16.8


U.S. Government Agency Obligations

3.0


Options

0.2


Short-Term Investments and Net Other Assets (Liabilities)

4.1




ASSET ALLOCATION (% of Fund's net assets)


&#160;



&#160;

U.S. Treasury Obligations - 58.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

U.S. Government Agency - Mortgage Securities - 17.6


&#160;

CMOs and Other Mortgage Related Securities - 16.8


&#160;

U.S. Government Agency Obligations - 3.0


&#160;

Options - 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;

Short-Term Investments and Net Other Assets (Liabilities) - 4.1


&#160;






</oef:HoldingsTableTextBlock>
    <oef:PctOfNav
      contextRef="C000038102_CD_0_Member"
      decimals="INF"
      id="ixv-307927"
      unitRef="pure">0.000</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038102_CD_1_Member"
      decimals="INF"
      id="ixv-307928"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038102_CD_2_Member"
      decimals="INF"
      id="ixv-307929"
      unitRef="pure">0.156</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038102_CD_3_Member"
      decimals="INF"
      id="ixv-307930"
      unitRef="pure">0.376</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038102_CD_4_Member"
      decimals="INF"
      id="ixv-307931"
      unitRef="pure">0.303</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038102_CD_5_Member"
      decimals="INF"
      id="ixv-307932"
      unitRef="pure">0.049</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038102_CD_6_Member"
      decimals="INF"
      id="ixv-307933"
      unitRef="pure">0.062</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038102_CD_7_Member"
      decimals="INF"
      id="ixv-307934"
      unitRef="pure">0.000</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038102_CD_8_Member"
      decimals="INF"
      id="ixv-307935"
      unitRef="pure">0.000</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038102_CD_9_Member"
      decimals="INF"
      id="ixv-307936"
      unitRef="pure">0.000</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038102_CD_10_Member"
      decimals="INF"
      id="ixv-307937"
      unitRef="pure">0.000</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038102_AA_USTreasuryObligations_Member"
      decimals="INF"
      id="ixv-307938"
      unitRef="pure">0.583</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038102_AA_USGovernmentAgencyMortgageSecurities_Member"
      decimals="INF"
      id="ixv-307939"
      unitRef="pure">0.176</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038102_AA_CMOsandOtherMortgageRelatedSecurities_Member"
      decimals="INF"
      id="ixv-307940"
      unitRef="pure">0.168</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038102_AA_USGovernmentAgencyObligations_Member"
      decimals="INF"
      id="ixv-307941"
      unitRef="pure">0.030</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038102_AA_Options_Member"
      decimals="INF"
      id="ixv-307942"
      unitRef="pure">0.002</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038102_AA_ShortTermInvestmentsandNetOtherAssetsLiabilities_Member"
      decimals="INF"
      id="ixv-307943"
      unitRef="pure">0.041</oef:PctOfNav>
    <oef:LargestHoldingsTableTextBlock contextRef="C000038102_ClassMember" id="ixv-14121">TOP HOLDINGS(% of Fund's net assets)

&#160;

&#160;


US Treasury Notes

40.8


&#160;


US Treasury Bonds

17.5


&#160;


Freddie Mac Multifamily Structured pass-thru certificates

10.5


&#160;


Fannie Mae Mortgage pass-thru certificates

9.3


&#160;


Freddie Mac Gold Pool

8.2


&#160;


Ginnie Mae II Pool

3.0


&#160;


Fannie Mae Guaranteed REMIC

2.3


&#160;


Federal Home Loan Bank

1.4


&#160;


Federal Farm Credit Banks Funding Corp

1.2


&#160;


Ginnie Mae I Pool

1.2


&#160;


&#160;

95.4

&#160;



</oef:LargestHoldingsTableTextBlock>
    <oef:PctOfNav
      contextRef="C000038102_TH_0_Member"
      decimals="INF"
      id="ixv-307944"
      unitRef="pure">0.408</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038102_TH_1_Member"
      decimals="INF"
      id="ixv-307945"
      unitRef="pure">0.175</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038102_TH_2_Member"
      decimals="INF"
      id="ixv-307946"
      unitRef="pure">0.105</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038102_TH_3_Member"
      decimals="INF"
      id="ixv-307947"
      unitRef="pure">0.093</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038102_TH_4_Member"
      decimals="INF"
      id="ixv-307948"
      unitRef="pure">0.082</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038102_TH_5_Member"
      decimals="INF"
      id="ixv-307949"
      unitRef="pure">0.030</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038102_TH_6_Member"
      decimals="INF"
      id="ixv-307950"
      unitRef="pure">0.023</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038102_TH_7_Member"
      decimals="INF"
      id="ixv-307951"
      unitRef="pure">0.014</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038102_TH_8_Member"
      decimals="INF"
      id="ixv-307952"
      unitRef="pure">0.012</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038102_TH_9_Member"
      decimals="INF"
      id="ixv-307953"
      unitRef="pure">0.012</oef:PctOfNav>
    <oef:MaterialFundChngTextBlock contextRef="C000038102_ClassMember" id="ixv-14246">
&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 modified its principal investment risks 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="C000038102_ClassMember" id="ixv-14252">&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="C000038102_ClassMember" id="ixv-14254">&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="C000038102_ClassMember" id="ixv-14257">&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="C000038102_ClassMember" id="ixv-14261">&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:MaterialFundChngRisksChngTextBlock contextRef="C000038102_ClassMember" id="ixv-14272">
&lt;div style="text-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 risks 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:MaterialFundChngRisksChngTextBlock>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-14330">2026-08-31</dei:DocumentPeriodEndDate>
    <oef:MaterialFundChngNoticeTextBlock contextRef="C000038100_ClassMember" id="ixv-14334">This report describes changes to the Fund that occurred during the reporting period.</oef:MaterialFundChngNoticeTextBlock>
    <oef:FundName contextRef="C000038100_ClassMember" id="ixv-14345">Fidelity&#xae; Government Income Fund</oef:FundName>
    <oef:ClassName contextRef="C000038100_ClassMember" id="ixv-14348">Fidelity Advisor&#xae; Government Income Fund Class C</oef:ClassName>
    <dei:TradingSymbol contextRef="C000038100_ClassMember" id="ixv-14352">FVICX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000038100_ClassMember" id="ixv-14371">This annual shareholder report contains information about Fidelity&#xae; Government Income Fund for the period September 1, 2025 to August 31, 2026.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000038100_ClassMember" id="ixv-14373">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000038100_ClassMember" id="ixv-14378">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="C000038100_ClassMember" id="ixv-14380">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000038100_ClassMember" id="ixv-14383">1-877-208-0098</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000038100_ClassMember" id="ixv-14386">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000038100_ClassMember" id="ixv-14393">&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;155&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;1.54&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="C000038100_ClassMember"
      decimals="0"
      id="ixv-307954"
      unitRef="usd">155</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000038100_ClassMember"
      decimals="INF"
      id="ixv-307955"
      unitRef="pure">0.0154</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000038100_ClassMember" id="ixv-14436">&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, fast-growing government debt 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, an overweight in Ginnie Mae securities with coupons of 2.0% and 2.5% contributed to the fund's performance versus the Bloomberg 75% U.S. Government/25% U.S. Mortgage-Backed Securities Blended 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;An overweight in conventional 30-year mortgage pools with specified characteristics and coupons of 2.5% and higher boosted relative performance, as did an overweight in short-duration Freddie Mac multifamily securities.&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 underweight in conventional 30-year mortgage-backed securities with a coupon of 2% detracted versus the index.&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 longer duration (interest rate) positioning hurt relative performance.&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;Lastly, a small position in Treasury Inflation-Protected Securities detracted.&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="C000038100_ClassMember" id="ixv-14460">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

$9,851


$9,590


$10,380


$10,874


$10,590


$9,343


$9,014


$9,485


$9,672


$9,799



Bloomberg 75% U.S. Government/25% U.S. Mortgage-Backed Securities Blended Index


$10,000

$9,957


$9,832


$10,765


$11,447


$11,269


$10,091


$9,888


$10,520


$10,801


$10,982



Bloomberg U.S. Government Bond Index


$10,000

$9,916


$9,767


$10,774


$11,519


$11,287


$10,080


$9,878


$10,474


$10,730


$10,862



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="C000038100_LG_ClassMember_11YR" id="ixv-14479">&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="C000038100_ClassMember_AsOf_2016"
      decimals="0"
      id="ixv-307956"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038100_ClassMember_AsOf_2017"
      decimals="0"
      id="ixv-307957"
      unitRef="usd">9851</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038100_ClassMember_AsOf_2018"
      decimals="0"
      id="ixv-307958"
      unitRef="usd">9590</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038100_ClassMember_AsOf_2019"
      decimals="0"
      id="ixv-307959"
      unitRef="usd">10380</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038100_ClassMember_AsOf_2020"
      decimals="0"
      id="ixv-307960"
      unitRef="usd">10874</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038100_ClassMember_AsOf_2021"
      decimals="0"
      id="ixv-307961"
      unitRef="usd">10590</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038100_ClassMember_AsOf_2022"
      decimals="0"
      id="ixv-307962"
      unitRef="usd">9343</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038100_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-307963"
      unitRef="usd">9014</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038100_ClassMember_AsOf_2024"
      decimals="0"
      id="ixv-307964"
      unitRef="usd">9485</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038100_ClassMember_AsOf_2025"
      decimals="0"
      id="ixv-307965"
      unitRef="usd">9672</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038100_ClassMember_AsOf_2026"
      decimals="0"
      id="ixv-307966"
      unitRef="usd">9799</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000038100_LG_1_AdditionalIndexMember_11YR"
      id="ixv-14528">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg 75% U.S. Government/25% U.S. Mortgage-Backed Securities Blended Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000038100_1_AdditionalIndexMember_AsOf_2016"
      decimals="0"
      id="ixv-307967"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038100_1_AdditionalIndexMember_AsOf_2017"
      decimals="0"
      id="ixv-307968"
      unitRef="usd">9957</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038100_1_AdditionalIndexMember_AsOf_2018"
      decimals="0"
      id="ixv-307969"
      unitRef="usd">9832</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038100_1_AdditionalIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-307970"
      unitRef="usd">10765</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038100_1_AdditionalIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-307971"
      unitRef="usd">11447</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038100_1_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-307972"
      unitRef="usd">11269</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038100_1_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-307973"
      unitRef="usd">10091</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038100_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-307974"
      unitRef="usd">9888</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038100_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-307975"
      unitRef="usd">10520</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038100_1_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-307976"
      unitRef="usd">10801</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038100_1_AdditionalIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-307977"
      unitRef="usd">10982</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000038100_LG_2_AdditionalIndexMember_11YR"
      id="ixv-14577">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg U.S. Government Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000038100_2_AdditionalIndexMember_AsOf_2016"
      decimals="0"
      id="ixv-307978"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038100_2_AdditionalIndexMember_AsOf_2017"
      decimals="0"
      id="ixv-307979"
      unitRef="usd">9916</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038100_2_AdditionalIndexMember_AsOf_2018"
      decimals="0"
      id="ixv-307980"
      unitRef="usd">9767</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038100_2_AdditionalIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-307981"
      unitRef="usd">10774</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038100_2_AdditionalIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-307982"
      unitRef="usd">11519</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038100_2_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-307983"
      unitRef="usd">11287</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038100_2_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-307984"
      unitRef="usd">10080</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038100_2_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-307985"
      unitRef="usd">9878</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038100_2_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-307986"
      unitRef="usd">10474</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038100_2_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-307987"
      unitRef="usd">10730</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038100_2_AdditionalIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-307988"
      unitRef="usd">10862</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000038100_0_LG_BBIndexMember_11YR"
      id="ixv-14626">&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="C000038100_0_BBIndexMember_AsOf_2016"
      decimals="0"
      id="ixv-307989"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038100_0_BBIndexMember_AsOf_2017"
      decimals="0"
      id="ixv-307990"
      unitRef="usd">10049</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038100_0_BBIndexMember_AsOf_2018"
      decimals="0"
      id="ixv-307991"
      unitRef="usd">9944</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038100_0_BBIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-307992"
      unitRef="usd">10955</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038100_0_BBIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-307993"
      unitRef="usd">11665</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038100_0_BBIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-307994"
      unitRef="usd">11655</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038100_0_BBIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-307995"
      unitRef="usd">10313</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038100_0_BBIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-307996"
      unitRef="usd">10189</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038100_0_BBIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-307997"
      unitRef="usd">10933</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038100_0_BBIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-307998"
      unitRef="usd">11276</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038100_0_BBIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-307999"
      unitRef="usd">11489</oef:AccmVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000038100_ClassMember" id="ixv-14726">AVERAGE ANNUAL TOTAL RETURNS:

&#160;

1 Year

5 Year

10 Year


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

-0.43%

-1.84%


-0.20%


Class C

0.55%

-1.84%

-0.20%


Bloomberg 75% U.S. Government/25% U.S. Mortgage-Backed Securities Blended Index

1.67%


-0.51%


0.94%


Bloomberg U.S. Government Bond Index

1.23%


-0.77%


0.83%


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="C000038100_ClassMember_1YR"
      decimals="INF"
      id="ixv-308000"
      unitRef="pure">-0.0043</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000038100_ClassMember_5YR"
      decimals="INF"
      id="ixv-308001"
      unitRef="pure">-0.0184</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000038100_ClassMember_10YR"
      decimals="INF"
      id="ixv-308002"
      unitRef="pure">-0.0020</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000038100_NoLoadClassMember_1YR"
      decimals="INF"
      id="ixv-308003"
      unitRef="pure">0.0055</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000038100_NoLoadClassMember_5YR"
      decimals="INF"
      id="ixv-308004"
      unitRef="pure">-0.0184</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000038100_NoLoadClassMember_10YR"
      decimals="INF"
      id="ixv-308005"
      unitRef="pure">-0.0020</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000038100_0_AdditionalIndexMember_1YR"
      decimals="INF"
      id="ixv-308006"
      unitRef="pure">0.0167</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000038100_0_AdditionalIndexMember_5YR"
      decimals="INF"
      id="ixv-308007"
      unitRef="pure">-0.0051</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000038100_0_AdditionalIndexMember_10YR"
      decimals="INF"
      id="ixv-308008"
      unitRef="pure">0.0094</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000038100_1_AdditionalIndexMember_1YR"
      decimals="INF"
      id="ixv-308009"
      unitRef="pure">0.0123</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000038100_1_AdditionalIndexMember_5YR"
      decimals="INF"
      id="ixv-308010"
      unitRef="pure">-0.0077</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000038100_1_AdditionalIndexMember_10YR"
      decimals="INF"
      id="ixv-308011"
      unitRef="pure">0.0083</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000038100_2_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-308012"
      unitRef="pure">0.0189</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000038100_2_BBIndexMember_5YR"
      decimals="INF"
      id="ixv-308013"
      unitRef="pure">-0.0029</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000038100_2_BBIndexMember_10YR"
      decimals="INF"
      id="ixv-308014"
      unitRef="pure">0.0140</oef:AvgAnnlRtrPct>
    <oef:UpdPerfInfoLocationTextBlock contextRef="C000038100_ClassMember" id="ixv-14835">&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="C000038100_ClassMember" id="ixv-14847">&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="C000038100_ClassMember" id="ixv-14851">&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="C000038100_ClassMember" id="ixv-14857">&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;$&lt;/span&gt;1,390,348,293&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;1,738&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;4,265,715&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;286&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="C000038100_InstantMember"
      decimals="0"
      id="ixv-308015"
      unitRef="usd">1390348293</us-gaap:AssetsNet>
    <oef:HoldingsCount
      contextRef="C000038100_InstantMember"
      decimals="INF"
      id="ixv-308016"
      unitRef="holding">1738</oef:HoldingsCount>
    <oef:AdvisoryFeesPaidAmt
      contextRef="C000038100_ClassMember"
      decimals="0"
      id="ixv-308017"
      unitRef="usd">4265715</oef:AdvisoryFeesPaidAmt>
    <us-gaap:InvestmentCompanyPortfolioTurnover
      contextRef="C000038100_ClassMember"
      decimals="INF"
      id="ixv-308018"
      unitRef="pure">2.86</us-gaap:InvestmentCompanyPortfolioTurnover>
    <oef:HoldingsTableTextBlock contextRef="C000038100_ClassMember" id="ixv-14932">
&#160;
COUPON DISTRIBUTION 
(% of Fund's net assets)


Zero coupon bonds

0.0

&#160;


1 - 1.99%

1.1

&#160;


2 - 2.99%

15.6

&#160;


3 - 3.99%

37.6

&#160;


4 - 4.99%

30.3

&#160;


5 - 5.99%

4.9

&#160;


6 - 6.99%

6.2

&#160;


7 - 7.99%

0.0

&#160;


8 - 8.99%

0.0

&#160;


17 - 17.99%

0.0

&#160;


18 - 18.99%

0.0

&#160;




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

58.3


U.S. Government Agency - Mortgage Securities

17.6


CMOs and Other Mortgage Related Securities

16.8


U.S. Government Agency Obligations

3.0


Options

0.2


Short-Term Investments and Net Other Assets (Liabilities)

4.1




ASSET ALLOCATION (% of Fund's net assets)


&#160;



&#160;

U.S. Treasury Obligations - 58.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

U.S. Government Agency - Mortgage Securities - 17.6


&#160;

CMOs and Other Mortgage Related Securities - 16.8


&#160;

U.S. Government Agency Obligations - 3.0


&#160;

Options - 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;

Short-Term Investments and Net Other Assets (Liabilities) - 4.1


&#160;






</oef:HoldingsTableTextBlock>
    <oef:PctOfNav
      contextRef="C000038100_CD_0_Member"
      decimals="INF"
      id="ixv-308019"
      unitRef="pure">0.000</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038100_CD_1_Member"
      decimals="INF"
      id="ixv-308020"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038100_CD_2_Member"
      decimals="INF"
      id="ixv-308021"
      unitRef="pure">0.156</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038100_CD_3_Member"
      decimals="INF"
      id="ixv-308022"
      unitRef="pure">0.376</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038100_CD_4_Member"
      decimals="INF"
      id="ixv-308023"
      unitRef="pure">0.303</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038100_CD_5_Member"
      decimals="INF"
      id="ixv-308024"
      unitRef="pure">0.049</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038100_CD_6_Member"
      decimals="INF"
      id="ixv-308025"
      unitRef="pure">0.062</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038100_CD_7_Member"
      decimals="INF"
      id="ixv-308026"
      unitRef="pure">0.000</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038100_CD_8_Member"
      decimals="INF"
      id="ixv-308027"
      unitRef="pure">0.000</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038100_CD_9_Member"
      decimals="INF"
      id="ixv-308028"
      unitRef="pure">0.000</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038100_CD_10_Member"
      decimals="INF"
      id="ixv-308029"
      unitRef="pure">0.000</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038100_AA_USTreasuryObligations_Member"
      decimals="INF"
      id="ixv-308030"
      unitRef="pure">0.583</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038100_AA_USGovernmentAgencyMortgageSecurities_Member"
      decimals="INF"
      id="ixv-308031"
      unitRef="pure">0.176</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038100_AA_CMOsandOtherMortgageRelatedSecurities_Member"
      decimals="INF"
      id="ixv-308032"
      unitRef="pure">0.168</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038100_AA_USGovernmentAgencyObligations_Member"
      decimals="INF"
      id="ixv-308033"
      unitRef="pure">0.030</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038100_AA_Options_Member"
      decimals="INF"
      id="ixv-308034"
      unitRef="pure">0.002</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038100_AA_ShortTermInvestmentsandNetOtherAssetsLiabilities_Member"
      decimals="INF"
      id="ixv-308035"
      unitRef="pure">0.041</oef:PctOfNav>
    <oef:LargestHoldingsTableTextBlock contextRef="C000038100_ClassMember" id="ixv-15156">TOP HOLDINGS(% of Fund's net assets)

&#160;

&#160;


US Treasury Notes

40.8


&#160;


US Treasury Bonds

17.5


&#160;


Freddie Mac Multifamily Structured pass-thru certificates

10.5


&#160;


Fannie Mae Mortgage pass-thru certificates

9.3


&#160;


Freddie Mac Gold Pool

8.2


&#160;


Ginnie Mae II Pool

3.0


&#160;


Fannie Mae Guaranteed REMIC

2.3


&#160;


Federal Home Loan Bank

1.4


&#160;


Federal Farm Credit Banks Funding Corp

1.2


&#160;


Ginnie Mae I Pool

1.2


&#160;


&#160;

95.4

&#160;



</oef:LargestHoldingsTableTextBlock>
    <oef:PctOfNav
      contextRef="C000038100_TH_0_Member"
      decimals="INF"
      id="ixv-308036"
      unitRef="pure">0.408</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038100_TH_1_Member"
      decimals="INF"
      id="ixv-308037"
      unitRef="pure">0.175</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038100_TH_2_Member"
      decimals="INF"
      id="ixv-308038"
      unitRef="pure">0.105</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038100_TH_3_Member"
      decimals="INF"
      id="ixv-308039"
      unitRef="pure">0.093</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038100_TH_4_Member"
      decimals="INF"
      id="ixv-308040"
      unitRef="pure">0.082</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038100_TH_5_Member"
      decimals="INF"
      id="ixv-308041"
      unitRef="pure">0.030</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038100_TH_6_Member"
      decimals="INF"
      id="ixv-308042"
      unitRef="pure">0.023</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038100_TH_7_Member"
      decimals="INF"
      id="ixv-308043"
      unitRef="pure">0.014</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038100_TH_8_Member"
      decimals="INF"
      id="ixv-308044"
      unitRef="pure">0.012</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038100_TH_9_Member"
      decimals="INF"
      id="ixv-308045"
      unitRef="pure">0.012</oef:PctOfNav>
    <oef:MaterialFundChngTextBlock contextRef="C000038100_ClassMember" id="ixv-15281">
&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 modified its principal investment risks 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="C000038100_ClassMember" id="ixv-15287">&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="C000038100_ClassMember" id="ixv-15289">&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="C000038100_ClassMember" id="ixv-15292">&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="C000038100_ClassMember" id="ixv-15296">&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:MaterialFundChngRisksChngTextBlock contextRef="C000038100_ClassMember" id="ixv-15307">
&lt;div style="text-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 risks 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:MaterialFundChngRisksChngTextBlock>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-15365">2026-08-31</dei:DocumentPeriodEndDate>
    <oef:MaterialFundChngNoticeTextBlock contextRef="C000038098_ClassMember" id="ixv-15369">This report describes changes to the Fund that occurred during the reporting period.</oef:MaterialFundChngNoticeTextBlock>
    <oef:FundName contextRef="C000038098_ClassMember" id="ixv-15380">Fidelity&#xae; Government Income Fund</oef:FundName>
    <oef:ClassName contextRef="C000038098_ClassMember" id="ixv-15383">Fidelity Advisor&#xae; Government Income Fund Class A</oef:ClassName>
    <dei:TradingSymbol contextRef="C000038098_ClassMember" id="ixv-15387">FVIAX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000038098_ClassMember" id="ixv-15406">This annual shareholder report contains information about Fidelity&#xae; Government Income Fund for the period September 1, 2025 to August 31, 2026.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000038098_ClassMember" id="ixv-15408">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000038098_ClassMember" id="ixv-15413">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="C000038098_ClassMember" id="ixv-15415">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000038098_ClassMember" id="ixv-15418">1-877-208-0098</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000038098_ClassMember" id="ixv-15421">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000038098_ClassMember" id="ixv-15428">&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;80&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;0.79&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="C000038098_ClassMember"
      decimals="0"
      id="ixv-308046"
      unitRef="usd">80</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000038098_ClassMember"
      decimals="INF"
      id="ixv-308047"
      unitRef="pure">0.0079</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000038098_ClassMember" id="ixv-15471">&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, fast-growing government debt 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, an overweight in Ginnie Mae securities with coupons of 2.0% and 2.5% contributed to the fund's performance versus the Bloomberg 75% U.S. Government/25% U.S. Mortgage-Backed Securities Blended 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;An overweight in conventional 30-year mortgage pools with specified characteristics and coupons of 2.5% and higher boosted relative performance, as did an overweight in short-duration Freddie Mac multifamily securities.&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 underweight in conventional 30-year mortgage-backed securities with a coupon of 2% detracted versus the index.&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 longer duration (interest rate) positioning hurt relative performance.&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;Lastly, a small position in Treasury Inflation-Protected Securities detracted.&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="C000038098_ClassMember" id="ixv-15495">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

$9,530


$9,350


$10,197


$10,768


$10,570


$9,396


$9,126


$9,684


$9,874


$10,005



Bloomberg 75% U.S. Government/25% U.S. Mortgage-Backed Securities Blended Index


$10,000

$9,957


$9,832


$10,765


$11,447


$11,269


$10,091


$9,888


$10,520


$10,801


$10,982



Bloomberg U.S. Government Bond Index


$10,000

$9,916


$9,767


$10,774


$11,519


$11,287


$10,080


$9,878


$10,474


$10,730


$10,862



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="C000038098_LG_ClassMember_11YR" id="ixv-15516">&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="C000038098_ClassMember_AsOf_2016"
      decimals="0"
      id="ixv-308048"
      unitRef="usd">9600</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038098_ClassMember_AsOf_2017"
      decimals="0"
      id="ixv-308049"
      unitRef="usd">9530</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038098_ClassMember_AsOf_2018"
      decimals="0"
      id="ixv-308050"
      unitRef="usd">9350</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038098_ClassMember_AsOf_2019"
      decimals="0"
      id="ixv-308051"
      unitRef="usd">10197</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038098_ClassMember_AsOf_2020"
      decimals="0"
      id="ixv-308052"
      unitRef="usd">10768</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038098_ClassMember_AsOf_2021"
      decimals="0"
      id="ixv-308053"
      unitRef="usd">10570</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038098_ClassMember_AsOf_2022"
      decimals="0"
      id="ixv-308054"
      unitRef="usd">9396</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038098_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-308055"
      unitRef="usd">9126</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038098_ClassMember_AsOf_2024"
      decimals="0"
      id="ixv-308056"
      unitRef="usd">9684</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038098_ClassMember_AsOf_2025"
      decimals="0"
      id="ixv-308057"
      unitRef="usd">9874</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038098_ClassMember_AsOf_2026"
      decimals="0"
      id="ixv-308058"
      unitRef="usd">10005</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000038098_LG_1_AdditionalIndexMember_11YR"
      id="ixv-15565">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg 75% U.S. Government/25% U.S. Mortgage-Backed Securities Blended Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000038098_1_AdditionalIndexMember_AsOf_2016"
      decimals="0"
      id="ixv-308059"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038098_1_AdditionalIndexMember_AsOf_2017"
      decimals="0"
      id="ixv-308060"
      unitRef="usd">9957</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038098_1_AdditionalIndexMember_AsOf_2018"
      decimals="0"
      id="ixv-308061"
      unitRef="usd">9832</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038098_1_AdditionalIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-308062"
      unitRef="usd">10765</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038098_1_AdditionalIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-308063"
      unitRef="usd">11447</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038098_1_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-308064"
      unitRef="usd">11269</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038098_1_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-308065"
      unitRef="usd">10091</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038098_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-308066"
      unitRef="usd">9888</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038098_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-308067"
      unitRef="usd">10520</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038098_1_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-308068"
      unitRef="usd">10801</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038098_1_AdditionalIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-308069"
      unitRef="usd">10982</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000038098_LG_2_AdditionalIndexMember_11YR"
      id="ixv-15614">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg U.S. Government Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000038098_2_AdditionalIndexMember_AsOf_2016"
      decimals="0"
      id="ixv-308070"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038098_2_AdditionalIndexMember_AsOf_2017"
      decimals="0"
      id="ixv-308071"
      unitRef="usd">9916</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038098_2_AdditionalIndexMember_AsOf_2018"
      decimals="0"
      id="ixv-308072"
      unitRef="usd">9767</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038098_2_AdditionalIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-308073"
      unitRef="usd">10774</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038098_2_AdditionalIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-308074"
      unitRef="usd">11519</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038098_2_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-308075"
      unitRef="usd">11287</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038098_2_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-308076"
      unitRef="usd">10080</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038098_2_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-308077"
      unitRef="usd">9878</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038098_2_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-308078"
      unitRef="usd">10474</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038098_2_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-308079"
      unitRef="usd">10730</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038098_2_AdditionalIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-308080"
      unitRef="usd">10862</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000038098_0_LG_BBIndexMember_11YR"
      id="ixv-15663">&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="C000038098_0_BBIndexMember_AsOf_2016"
      decimals="0"
      id="ixv-308081"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038098_0_BBIndexMember_AsOf_2017"
      decimals="0"
      id="ixv-308082"
      unitRef="usd">10049</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038098_0_BBIndexMember_AsOf_2018"
      decimals="0"
      id="ixv-308083"
      unitRef="usd">9944</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038098_0_BBIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-308084"
      unitRef="usd">10955</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038098_0_BBIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-308085"
      unitRef="usd">11665</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038098_0_BBIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-308086"
      unitRef="usd">11655</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038098_0_BBIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-308087"
      unitRef="usd">10313</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038098_0_BBIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-308088"
      unitRef="usd">10189</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038098_0_BBIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-308089"
      unitRef="usd">10933</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038098_0_BBIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-308090"
      unitRef="usd">11276</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000038098_0_BBIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-308091"
      unitRef="usd">11489</oef:AccmVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000038098_ClassMember" id="ixv-15763">AVERAGE ANNUAL TOTAL RETURNS:

&#160;

1 Year

5 Year

10 Year


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

-2.73%

-1.90%


0.00%


Class A (without 4.00% sales charge)

1.32%

-1.09%

0.41%


Bloomberg 75% U.S. Government/25% U.S. Mortgage-Backed Securities Blended Index

1.67%


-0.51%


0.94%


Bloomberg U.S. Government Bond Index

1.23%


-0.77%


0.83%


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="C000038098_ClassMember_1YR"
      decimals="INF"
      id="ixv-308092"
      unitRef="pure">-0.0273</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000038098_ClassMember_5YR"
      decimals="INF"
      id="ixv-308093"
      unitRef="pure">-0.0190</oef:AvgAnnlRtrPct>
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      contextRef="C000038098_ClassMember_10YR"
      decimals="INF"
      id="ixv-308094"
      unitRef="pure">0.0000</oef:AvgAnnlRtrPct>
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      contextRef="C000038098_NoLoadClassMember_1YR"
      decimals="INF"
      id="ixv-308095"
      unitRef="pure">0.0132</oef:AvgAnnlRtrPct>
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      contextRef="C000038098_NoLoadClassMember_5YR"
      decimals="INF"
      id="ixv-308096"
      unitRef="pure">-0.0109</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000038098_NoLoadClassMember_10YR"
      decimals="INF"
      id="ixv-308097"
      unitRef="pure">0.0041</oef:AvgAnnlRtrPct>
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      contextRef="C000038098_0_AdditionalIndexMember_1YR"
      decimals="INF"
      id="ixv-308098"
      unitRef="pure">0.0167</oef:AvgAnnlRtrPct>
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      contextRef="C000038098_0_AdditionalIndexMember_5YR"
      decimals="INF"
      id="ixv-308099"
      unitRef="pure">-0.0051</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000038098_0_AdditionalIndexMember_10YR"
      decimals="INF"
      id="ixv-308100"
      unitRef="pure">0.0094</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000038098_1_AdditionalIndexMember_1YR"
      decimals="INF"
      id="ixv-308101"
      unitRef="pure">0.0123</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000038098_1_AdditionalIndexMember_5YR"
      decimals="INF"
      id="ixv-308102"
      unitRef="pure">-0.0077</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000038098_1_AdditionalIndexMember_10YR"
      decimals="INF"
      id="ixv-308103"
      unitRef="pure">0.0083</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000038098_2_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-308104"
      unitRef="pure">0.0189</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000038098_2_BBIndexMember_5YR"
      decimals="INF"
      id="ixv-308105"
      unitRef="pure">-0.0029</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000038098_2_BBIndexMember_10YR"
      decimals="INF"
      id="ixv-308106"
      unitRef="pure">0.0140</oef:AvgAnnlRtrPct>
    <oef:UpdPerfInfoLocationTextBlock contextRef="C000038098_ClassMember" id="ixv-15869">&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="C000038098_ClassMember" id="ixv-15881">&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="C000038098_ClassMember" id="ixv-15885">&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="C000038098_ClassMember" id="ixv-15891">&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;$&lt;/span&gt;1,390,348,293&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;1,738&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;4,265,715&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;286&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="C000038098_InstantMember"
      decimals="0"
      id="ixv-308107"
      unitRef="usd">1390348293</us-gaap:AssetsNet>
    <oef:HoldingsCount
      contextRef="C000038098_InstantMember"
      decimals="INF"
      id="ixv-308108"
      unitRef="holding">1738</oef:HoldingsCount>
    <oef:AdvisoryFeesPaidAmt
      contextRef="C000038098_ClassMember"
      decimals="0"
      id="ixv-308109"
      unitRef="usd">4265715</oef:AdvisoryFeesPaidAmt>
    <us-gaap:InvestmentCompanyPortfolioTurnover
      contextRef="C000038098_ClassMember"
      decimals="INF"
      id="ixv-308110"
      unitRef="pure">2.86</us-gaap:InvestmentCompanyPortfolioTurnover>
    <oef:HoldingsTableTextBlock contextRef="C000038098_ClassMember" id="ixv-15966">
&#160;
COUPON DISTRIBUTION 
(% of Fund's net assets)


Zero coupon bonds

0.0

&#160;


1 - 1.99%

1.1

&#160;


2 - 2.99%

15.6

&#160;


3 - 3.99%

37.6

&#160;


4 - 4.99%

30.3

&#160;


5 - 5.99%

4.9

&#160;


6 - 6.99%

6.2

&#160;


7 - 7.99%

0.0

&#160;


8 - 8.99%

0.0

&#160;


17 - 17.99%

0.0

&#160;


18 - 18.99%

0.0

&#160;




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

58.3


U.S. Government Agency - Mortgage Securities

17.6


CMOs and Other Mortgage Related Securities

16.8


U.S. Government Agency Obligations

3.0


Options

0.2


Short-Term Investments and Net Other Assets (Liabilities)

4.1




ASSET ALLOCATION (% of Fund's net assets)


&#160;



&#160;

U.S. Treasury Obligations - 58.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

U.S. Government Agency - Mortgage Securities - 17.6


&#160;

CMOs and Other Mortgage Related Securities - 16.8


&#160;

U.S. Government Agency Obligations - 3.0


&#160;

Options - 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;

Short-Term Investments and Net Other Assets (Liabilities) - 4.1


&#160;






</oef:HoldingsTableTextBlock>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-308111"
      unitRef="pure">0.000</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038098_CD_1_Member"
      decimals="INF"
      id="ixv-308112"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038098_CD_2_Member"
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      id="ixv-308113"
      unitRef="pure">0.156</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038098_CD_3_Member"
      decimals="INF"
      id="ixv-308114"
      unitRef="pure">0.376</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038098_CD_4_Member"
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      id="ixv-308115"
      unitRef="pure">0.303</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038098_CD_5_Member"
      decimals="INF"
      id="ixv-308116"
      unitRef="pure">0.049</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038098_CD_6_Member"
      decimals="INF"
      id="ixv-308117"
      unitRef="pure">0.062</oef:PctOfNav>
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      contextRef="C000038098_CD_7_Member"
      decimals="INF"
      id="ixv-308118"
      unitRef="pure">0.000</oef:PctOfNav>
    <oef:PctOfNav
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      id="ixv-308119"
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    <oef:PctOfNav
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      decimals="INF"
      id="ixv-308122"
      unitRef="pure">0.583</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038098_AA_USGovernmentAgencyMortgageSecurities_Member"
      decimals="INF"
      id="ixv-308123"
      unitRef="pure">0.176</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038098_AA_CMOsandOtherMortgageRelatedSecurities_Member"
      decimals="INF"
      id="ixv-308124"
      unitRef="pure">0.168</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038098_AA_USGovernmentAgencyObligations_Member"
      decimals="INF"
      id="ixv-308125"
      unitRef="pure">0.030</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038098_AA_Options_Member"
      decimals="INF"
      id="ixv-308126"
      unitRef="pure">0.002</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038098_AA_ShortTermInvestmentsandNetOtherAssetsLiabilities_Member"
      decimals="INF"
      id="ixv-308127"
      unitRef="pure">0.041</oef:PctOfNav>
    <oef:LargestHoldingsTableTextBlock contextRef="C000038098_ClassMember" id="ixv-16190">TOP HOLDINGS(% of Fund's net assets)

&#160;

&#160;


US Treasury Notes

40.8


&#160;


US Treasury Bonds

17.5


&#160;


Freddie Mac Multifamily Structured pass-thru certificates

10.5


&#160;


Fannie Mae Mortgage pass-thru certificates

9.3


&#160;


Freddie Mac Gold Pool

8.2


&#160;


Ginnie Mae II Pool

3.0


&#160;


Fannie Mae Guaranteed REMIC

2.3


&#160;


Federal Home Loan Bank

1.4


&#160;


Federal Farm Credit Banks Funding Corp

1.2


&#160;


Ginnie Mae I Pool

1.2


&#160;


&#160;

95.4

&#160;



</oef:LargestHoldingsTableTextBlock>
    <oef:PctOfNav
      contextRef="C000038098_TH_0_Member"
      decimals="INF"
      id="ixv-308128"
      unitRef="pure">0.408</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038098_TH_1_Member"
      decimals="INF"
      id="ixv-308129"
      unitRef="pure">0.175</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038098_TH_2_Member"
      decimals="INF"
      id="ixv-308130"
      unitRef="pure">0.105</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038098_TH_3_Member"
      decimals="INF"
      id="ixv-308131"
      unitRef="pure">0.093</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038098_TH_4_Member"
      decimals="INF"
      id="ixv-308132"
      unitRef="pure">0.082</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038098_TH_5_Member"
      decimals="INF"
      id="ixv-308133"
      unitRef="pure">0.030</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038098_TH_6_Member"
      decimals="INF"
      id="ixv-308134"
      unitRef="pure">0.023</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038098_TH_7_Member"
      decimals="INF"
      id="ixv-308135"
      unitRef="pure">0.014</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038098_TH_8_Member"
      decimals="INF"
      id="ixv-308136"
      unitRef="pure">0.012</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000038098_TH_9_Member"
      decimals="INF"
      id="ixv-308137"
      unitRef="pure">0.012</oef:PctOfNav>
    <oef:MaterialFundChngTextBlock contextRef="C000038098_ClassMember" id="ixv-16315">
&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 modified its principal investment risks 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="C000038098_ClassMember" id="ixv-16321">&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="C000038098_ClassMember" id="ixv-16323">&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="C000038098_ClassMember" id="ixv-16326">&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="C000038098_ClassMember" id="ixv-16330">&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:MaterialFundChngRisksChngTextBlock contextRef="C000038098_ClassMember" id="ixv-16341">
&lt;div style="text-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 risks 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:MaterialFundChngRisksChngTextBlock>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-16399">2026-08-31</dei:DocumentPeriodEndDate>
    <oef:FundName contextRef="C000227903_ClassMember" id="ixv-16411">Fidelity&#xae; Environmental Bond Fund</oef:FundName>
    <oef:ClassName contextRef="C000227903_ClassMember" id="ixv-16414">Fidelity&#xae; Environmental Bond Fund</oef:ClassName>
    <dei:TradingSymbol contextRef="C000227903_ClassMember" id="ixv-16418">FFEBX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000227903_ClassMember" id="ixv-16437">This annual shareholder report contains information about Fidelity&#xae; Environmental Bond Fund for the period September 1, 2025 to August 31, 2026.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000227903_ClassMember" id="ixv-16439">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000227903_ClassMember" id="ixv-16444">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="C000227903_ClassMember" id="ixv-16446">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000227903_ClassMember" id="ixv-16449">1-800-544-8544</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000227903_ClassMember" id="ixv-16452">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000227903_ClassMember" id="ixv-16459">&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 $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:51%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity&#xae; Environmental Bond Fund&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:21%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&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="C000227903_ClassMember"
      decimals="0"
      id="ixv-308138"
      unitRef="usd">45</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000227903_ClassMember"
      decimals="INF"
      id="ixv-308139"
      unitRef="pure">0.0045</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000227903_ClassMember" id="ixv-16502">&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&#160; &#160;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, an underweight in mortgage-backed securities detracted from the fund's performance versus the benchmark Bloomberg U.S. Aggregate Bond 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;The fund's yield-curve positioning also hurt.&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, positioning among investment-grade corporate bonds, particularly above-benchmark exposure to financials and security selection among industrials, contributed to 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;The fund's use of derivatives and currency contracts to hedge certain aspects of the portfolio's global holdings 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;Notable changes over the past 12 months included decreasing exposure to U.S. Treasurys and increasing the allocations to corporate-backed bonds and mortgage-backed securities in the second half of the period.&lt;/span&gt;&lt;/div&gt;
&lt;div&gt;&lt;span style="font-size:12px;"&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;/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="C000227903_ClassMember" id="ixv-16531">How did the Fund perform over the life of Fund?

 &#160;&#160;
CUMULATIVE PERFORMANCE
June 15, 2021 through August 31, 2026. 
Initial investment of $10,000.
Fidelity&#xae; Environmental Bond Fund


$10,000

$10,116


$8,841


$8,748


$9,411


$9,699



Bloomberg MSCI Global Green USD Bond Index (Hedged USD)


$10,000

$10,120


$8,921


$8,966


$9,691


$10,139



Bloomberg U.S. Aggregate Bond Index


$10,000

$10,126


$8,960


$8,853


$9,499


$9,796



&#160;

2021

2022

2023

2024

2025

2026









&#160;
</oef:LineGraphTableTextBlock>
    <oef:LineGraphAndTableMeasureName contextRef="C000227903_LG_ClassMember_6YR" id="ixv-16550">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity&#xae; Environmental Bond Fund&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000227903_ClassMember_AsOf_2021"
      decimals="0"
      id="ixv-308140"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000227903_ClassMember_AsOf_2022"
      decimals="0"
      id="ixv-308141"
      unitRef="usd">10116</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000227903_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-308142"
      unitRef="usd">8841</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000227903_ClassMember_AsOf_2024"
      decimals="0"
      id="ixv-308143"
      unitRef="usd">8748</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000227903_ClassMember_AsOf_2025"
      decimals="0"
      id="ixv-308144"
      unitRef="usd">9411</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000227903_ClassMember_AsOf_2026"
      decimals="0"
      id="ixv-308145"
      unitRef="usd">9699</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000227903_LG_1_AdditionalIndexMember_6YR"
      id="ixv-16579">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg MSCI Global Green USD Bond Index (Hedged USD)&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000227903_1_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-308146"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000227903_1_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-308147"
      unitRef="usd">10120</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000227903_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-308148"
      unitRef="usd">8921</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000227903_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-308149"
      unitRef="usd">8966</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000227903_1_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-308150"
      unitRef="usd">9691</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000227903_1_AdditionalIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-308151"
      unitRef="usd">10139</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000227903_LG_2_AdditionalIndexMember_6YR"
      id="ixv-16608">&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="C000227903_2_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-308152"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000227903_2_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-308153"
      unitRef="usd">10126</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000227903_2_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-308154"
      unitRef="usd">8960</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000227903_2_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-308155"
      unitRef="usd">8853</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000227903_2_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-308156"
      unitRef="usd">9499</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000227903_2_AdditionalIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-308157"
      unitRef="usd">9796</oef:AccmVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000227903_ClassMember" id="ixv-16674">AVERAGE ANNUAL TOTAL RETURNS:

&#160;

1 Year

5 Year

Life of Fund&#160;A


Fidelity&#xae; Environmental Bond Fund

1.51%

-0.54%

-0.30%


Bloomberg MSCI Global Green USD Bond Index (Hedged USD)

2.39%


0.51%


0.72%


Bloomberg U.S. Aggregate Bond Index

1.89%


-0.29%


-0.04%




A&#160; &#160;From June 15, 2021

&#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="C000227903_NoLoadClassMember_1YR"
      decimals="INF"
      id="ixv-308158"
      unitRef="pure">0.0151</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000227903_NoLoadClassMember_5YR"
      decimals="INF"
      id="ixv-308159"
      unitRef="pure">-0.0054</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000227903_NoLoadClassMember_2025-09-01_2026-08-31"
      decimals="INF"
      id="ixv-308160"
      unitRef="pure">-0.0030</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000227903_0_AdditionalIndexMember_1YR"
      decimals="INF"
      id="ixv-308161"
      unitRef="pure">0.0239</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000227903_0_AdditionalIndexMember_5YR"
      decimals="INF"
      id="ixv-308162"
      unitRef="pure">0.0051</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000227903_0_AdditionalIndexMember_LOC"
      decimals="INF"
      id="ixv-308163"
      unitRef="pure">0.0072</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000227903_1_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-308164"
      unitRef="pure">0.0189</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000227903_1_BBIndexMember_5YR"
      decimals="INF"
      id="ixv-308165"
      unitRef="pure">-0.0029</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000227903_1_BBIndexMember_LOC"
      decimals="INF"
      id="ixv-308166"
      unitRef="pure">-0.0004</oef:AvgAnnlRtrPct>
    <oef:PerfInceptionDate
      contextRef="C000227903_Perf_2021-06-15_ClassMember"
      id="ixv-16747">2021-06-15</oef:PerfInceptionDate>
    <oef:UpdPerfInfoLocationTextBlock contextRef="C000227903_ClassMember" id="ixv-16757">&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="C000227903_ClassMember" id="ixv-16769">&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="C000227903_ClassMember" id="ixv-16773">&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="C000227903_ClassMember" id="ixv-16779">&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;$&lt;/span&gt;35,022,546&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;216&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;153,454&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;67&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="C000227903_InstantMember"
      decimals="0"
      id="ixv-308167"
      unitRef="usd">35022546</us-gaap:AssetsNet>
    <oef:HoldingsCount
      contextRef="C000227903_InstantMember"
      decimals="INF"
      id="ixv-308168"
      unitRef="holding">216</oef:HoldingsCount>
    <oef:AdvisoryFeesPaidAmt
      contextRef="C000227903_ClassMember"
      decimals="0"
      id="ixv-308169"
      unitRef="usd">153454</oef:AdvisoryFeesPaidAmt>
    <us-gaap:InvestmentCompanyPortfolioTurnover
      contextRef="C000227903_ClassMember"
      decimals="INF"
      id="ixv-308170"
      unitRef="pure">0.67</us-gaap:InvestmentCompanyPortfolioTurnover>
    <oef:HoldingsTableTextBlock contextRef="C000227903_ClassMember" id="ixv-16854">
&#160;
U.S. Government and U.S. Government Agency Obligations

52.7


AAA

0.7


AA

0.6


A

15.4


BBB

22.8


BB

3.3


Not Rated

3.4


Short-Term Investments and Net Other Assets (Liabilities)

1.1




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

U.S. Government and U.S. Government Agency Obligations - 52.7


&#160;

AAA - 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;

AA - 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;&#160;&#160;


&#160;

A - 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;&#160;


&#160;

BBB - 22.8&#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;

BB - 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;&#160;


&#160;

Not Rated - 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;

Short-Term Investments and Net Other Assets (Liabilities) - 1.1


&#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

40.5


U.S. Treasury Obligations

35.0


U.S. Government Agency - Mortgage Securities

17.7


CMOs and Other Mortgage Related Securities

2.6


Foreign Government and Government Agency Obligations

1.4


Preferred Securities

1.3


Asset-Backed Securities

0.4


Short-Term Investments and Net Other Assets (Liabilities)

1.1




ASSET ALLOCATION (% of Fund's net assets)


&#160;



&#160;

Corporate Bonds - 40.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

U.S. Treasury Obligations - 35.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

U.S. Government Agency - Mortgage Securities - 17.7


&#160;

CMOs and Other Mortgage Related Securities - 2.6


&#160;

Foreign Government and Government Agency Obligations - 1.4


&#160;

Preferred Securities - 1.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Asset-Backed Securities - 0.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Short-Term Investments and Net Other Assets (Liabilities) - 1.1


&#160;






United States

79.6


United Kingdom

4.4


Germany

3.1


Netherlands

2.3


Italy

2.0


Canada

1.5


Ireland

1.3


Japan

1.1


Luxembourg

1.0


Others

3.7




GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

United States - 79.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

United Kingdom - 4.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Germany - 3.1&#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;

Netherlands - 2.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Italy - 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;&#160;


&#160;

Canada - 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;

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;

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;

Luxembourg - 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;

Others - 3.7&#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
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      decimals="INF"
      id="ixv-308171"
      unitRef="pure">0.527</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227903_QD_AAA_Member"
      decimals="INF"
      id="ixv-308172"
      unitRef="pure">0.007</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227903_QD_AA_Member"
      decimals="INF"
      id="ixv-308173"
      unitRef="pure">0.006</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227903_QD_A_Member"
      decimals="INF"
      id="ixv-308174"
      unitRef="pure">0.154</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227903_QD_BBB_Member"
      decimals="INF"
      id="ixv-308175"
      unitRef="pure">0.228</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227903_QD_BB_Member"
      decimals="INF"
      id="ixv-308176"
      unitRef="pure">0.033</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227903_QD_NotRated_Member"
      decimals="INF"
      id="ixv-308177"
      unitRef="pure">0.034</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227903_QD_ShortTermInvestmentsandNetOtherAssetsLiabilities_Member"
      decimals="INF"
      id="ixv-308178"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227903_AA_CorporateBonds_Member"
      decimals="INF"
      id="ixv-308179"
      unitRef="pure">0.405</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227903_AA_USTreasuryObligations_Member"
      decimals="INF"
      id="ixv-308180"
      unitRef="pure">0.350</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227903_AA_USGovernmentAgencyMortgageSecurities_Member"
      decimals="INF"
      id="ixv-308181"
      unitRef="pure">0.177</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227903_AA_CMOsandOtherMortgageRelatedSecurities_Member"
      decimals="INF"
      id="ixv-308182"
      unitRef="pure">0.026</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227903_AA_ForeignGovernmentandGovernmentAgencyObligations_Member"
      decimals="INF"
      id="ixv-308183"
      unitRef="pure">0.014</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227903_AA_PreferredSecurities_Member"
      decimals="INF"
      id="ixv-308184"
      unitRef="pure">0.013</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227903_AA_AssetBackedSecurities_Member"
      decimals="INF"
      id="ixv-308185"
      unitRef="pure">0.004</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227903_AA_ShortTermInvestmentsandNetOtherAssetsLiabilities_Member"
      decimals="INF"
      id="ixv-308186"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227903_GD_US_Member"
      decimals="INF"
      id="ixv-308187"
      unitRef="pure">0.796</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227903_GD_GB_Member"
      decimals="INF"
      id="ixv-308188"
      unitRef="pure">0.044</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227903_GD_DE_Member"
      decimals="INF"
      id="ixv-308189"
      unitRef="pure">0.031</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227903_GD_NL_Member"
      decimals="INF"
      id="ixv-308190"
      unitRef="pure">0.023</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227903_GD_IT_Member"
      decimals="INF"
      id="ixv-308191"
      unitRef="pure">0.020</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227903_GD_CA_Member"
      decimals="INF"
      id="ixv-308192"
      unitRef="pure">0.015</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227903_GD_IE_Member"
      decimals="INF"
      id="ixv-308193"
      unitRef="pure">0.013</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227903_GD_JP_Member"
      decimals="INF"
      id="ixv-308194"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227903_GD_LU_Member"
      decimals="INF"
      id="ixv-308195"
      unitRef="pure">0.010</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227903_GD_Other_Member"
      decimals="INF"
      id="ixv-308196"
      unitRef="pure">0.037</oef:PctOfNav>
    <oef:LargestHoldingsTableTextBlock contextRef="C000227903_ClassMember" id="ixv-17289">TOP HOLDINGS(% of Fund's net assets)

&#160;

&#160;


US Treasury Notes

23.7


&#160;


US Treasury Bonds

11.3


&#160;


Freddie Mac Gold Pool

11.3


&#160;


Fannie Mae Mortgage pass-thru certificates

6.0


&#160;


Freddie Mac Multifamily Structured pass-thru certificates

2.3


&#160;


Morgan Stanley

1.8


&#160;


JPMorgan Chase &amp; Co

1.3


&#160;


AES Corp/The

1.0


&#160;


Consolidated Edison Co of New York Inc

1.0


&#160;


NatWest Group PLC

0.9


&#160;


&#160;

60.6

&#160;



</oef:LargestHoldingsTableTextBlock>
    <oef:PctOfNav
      contextRef="C000227903_TH_0_Member"
      decimals="INF"
      id="ixv-308197"
      unitRef="pure">0.237</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227903_TH_1_Member"
      decimals="INF"
      id="ixv-308198"
      unitRef="pure">0.113</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227903_TH_2_Member"
      decimals="INF"
      id="ixv-308199"
      unitRef="pure">0.113</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227903_TH_3_Member"
      decimals="INF"
      id="ixv-308200"
      unitRef="pure">0.060</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227903_TH_4_Member"
      decimals="INF"
      id="ixv-308201"
      unitRef="pure">0.023</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227903_TH_5_Member"
      decimals="INF"
      id="ixv-308202"
      unitRef="pure">0.018</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227903_TH_6_Member"
      decimals="INF"
      id="ixv-308203"
      unitRef="pure">0.013</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227903_TH_7_Member"
      decimals="INF"
      id="ixv-308204"
      unitRef="pure">0.010</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227903_TH_8_Member"
      decimals="INF"
      id="ixv-308205"
      unitRef="pure">0.010</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227903_TH_9_Member"
      decimals="INF"
      id="ixv-308206"
      unitRef="pure">0.009</oef:PctOfNav>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-17460">2026-08-31</dei:DocumentPeriodEndDate>
    <oef:FundName contextRef="C000227906_ClassMember" id="ixv-17472">Fidelity&#xae; Environmental Bond Fund</oef:FundName>
    <oef:ClassName contextRef="C000227906_ClassMember" id="ixv-17475">Fidelity Advisor&#xae; Environmental Bond Fund Class Z</oef:ClassName>
    <dei:TradingSymbol contextRef="C000227906_ClassMember" id="ixv-17479">FEBGX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000227906_ClassMember" id="ixv-17498">This annual shareholder report contains information about Fidelity&#xae; Environmental Bond Fund for the period September 1, 2025 to August 31, 2026.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000227906_ClassMember" id="ixv-17500">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000227906_ClassMember" id="ixv-17505">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="C000227906_ClassMember" id="ixv-17507">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000227906_ClassMember" id="ixv-17510">1-877-208-0098</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000227906_ClassMember" id="ixv-17513">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000227906_ClassMember" id="ixv-17520">&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="C000227906_ClassMember"
      decimals="0"
      id="ixv-308207"
      unitRef="usd">36</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000227906_ClassMember"
      decimals="INF"
      id="ixv-308208"
      unitRef="pure">0.0036</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000227906_ClassMember" id="ixv-17563">&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&#160; &#160;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, an underweight in mortgage-backed securities detracted from the fund's performance versus the benchmark Bloomberg U.S. Aggregate Bond 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;The fund's yield-curve positioning also hurt.&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, positioning among investment-grade corporate bonds, particularly above-benchmark exposure to financials and security selection among industrials, contributed to 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;The fund's use of derivatives and currency contracts to hedge certain aspects of the portfolio's global holdings 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;Notable changes over the past 12 months included decreasing exposure to U.S. Treasurys and increasing the allocations to corporate-backed bonds and mortgage-backed securities in the second half of the period.&lt;/span&gt;&lt;/div&gt;
&lt;div&gt;&lt;span style="font-size:12px;"&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;/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="C000227906_ClassMember" id="ixv-17592">How did the Fund perform over the life of Fund?

 &#160;&#160;
CUMULATIVE PERFORMANCE
June 15, 2021 through August 31, 2026. 
Initial investment of $10,000.
Class Z


$10,000

$10,118


$8,851


$8,766


$9,438


$9,736



Bloomberg MSCI Global Green USD Bond Index (Hedged USD)


$10,000

$10,120


$8,921


$8,966


$9,691


$10,139



Bloomberg U.S. Aggregate Bond Index


$10,000

$10,126


$8,960


$8,853


$9,499


$9,796



&#160;

2021

2022

2023

2024

2025

2026









&#160;
</oef:LineGraphTableTextBlock>
    <oef:LineGraphAndTableMeasureName contextRef="C000227906_LG_ClassMember_6YR" id="ixv-17611">&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="C000227906_ClassMember_AsOf_2021"
      decimals="0"
      id="ixv-308209"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000227906_ClassMember_AsOf_2022"
      decimals="0"
      id="ixv-308210"
      unitRef="usd">10118</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000227906_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-308211"
      unitRef="usd">8851</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000227906_ClassMember_AsOf_2024"
      decimals="0"
      id="ixv-308212"
      unitRef="usd">8766</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000227906_ClassMember_AsOf_2025"
      decimals="0"
      id="ixv-308213"
      unitRef="usd">9438</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000227906_ClassMember_AsOf_2026"
      decimals="0"
      id="ixv-308214"
      unitRef="usd">9736</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000227906_LG_1_AdditionalIndexMember_6YR"
      id="ixv-17640">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg MSCI Global Green USD Bond Index (Hedged USD)&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000227906_1_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-308215"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000227906_1_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-308216"
      unitRef="usd">10120</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000227906_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-308217"
      unitRef="usd">8921</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000227906_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-308218"
      unitRef="usd">8966</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000227906_1_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-308219"
      unitRef="usd">9691</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000227906_1_AdditionalIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-308220"
      unitRef="usd">10139</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000227906_LG_2_AdditionalIndexMember_6YR"
      id="ixv-17669">&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="C000227906_2_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-308221"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000227906_2_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-308222"
      unitRef="usd">10126</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000227906_2_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-308223"
      unitRef="usd">8960</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000227906_2_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-308224"
      unitRef="usd">8853</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000227906_2_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-308225"
      unitRef="usd">9499</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000227906_2_AdditionalIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-308226"
      unitRef="usd">9796</oef:AccmVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000227906_ClassMember" id="ixv-17735">AVERAGE ANNUAL TOTAL RETURNS:

&#160;

1 Year

5 Year

Life of Fund&#160;A


Class Z

1.60%

-0.45%

-0.21%


Bloomberg MSCI Global Green USD Bond Index (Hedged USD)

2.39%


0.51%


0.72%


Bloomberg U.S. Aggregate Bond Index

1.89%


-0.29%


-0.04%




A&#160; &#160;From June 15, 2021

&#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="C000227906_NoLoadClassMember_1YR"
      decimals="INF"
      id="ixv-308227"
      unitRef="pure">0.0160</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000227906_NoLoadClassMember_5YR"
      decimals="INF"
      id="ixv-308228"
      unitRef="pure">-0.0045</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000227906_NoLoadClassMember_2025-09-01_2026-08-31"
      decimals="INF"
      id="ixv-308229"
      unitRef="pure">-0.0021</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000227906_0_AdditionalIndexMember_1YR"
      decimals="INF"
      id="ixv-308230"
      unitRef="pure">0.0239</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000227906_0_AdditionalIndexMember_5YR"
      decimals="INF"
      id="ixv-308231"
      unitRef="pure">0.0051</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000227906_0_AdditionalIndexMember_LOC"
      decimals="INF"
      id="ixv-308232"
      unitRef="pure">0.0072</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000227906_1_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-308233"
      unitRef="pure">0.0189</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000227906_1_BBIndexMember_5YR"
      decimals="INF"
      id="ixv-308234"
      unitRef="pure">-0.0029</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
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      id="ixv-308235"
      unitRef="pure">-0.0004</oef:AvgAnnlRtrPct>
    <oef:PerfInceptionDate
      contextRef="C000227906_Perf_2021-06-15_ClassMember"
      id="ixv-17808">2021-06-15</oef:PerfInceptionDate>
    <oef:UpdPerfInfoLocationTextBlock contextRef="C000227906_ClassMember" id="ixv-17818">&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="C000227906_ClassMember" id="ixv-17830">&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="C000227906_ClassMember" id="ixv-17834">&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="C000227906_ClassMember" id="ixv-17840">&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;$&lt;/span&gt;35,022,546&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;216&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;153,454&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;67&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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    <oef:HoldingsTableTextBlock contextRef="C000227906_ClassMember" id="ixv-17915">
&#160;
U.S. Government and U.S. Government Agency Obligations

52.7


AAA

0.7


AA

0.6


A

15.4


BBB

22.8


BB

3.3


Not Rated

3.4


Short-Term Investments and Net Other Assets (Liabilities)

1.1




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

U.S. Government and U.S. Government Agency Obligations - 52.7


&#160;

AAA - 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;

AA - 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;&#160;&#160;


&#160;

A - 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;&#160;


&#160;

BBB - 22.8&#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;

BB - 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;&#160;


&#160;

Not Rated - 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;

Short-Term Investments and Net Other Assets (Liabilities) - 1.1


&#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

40.5


U.S. Treasury Obligations

35.0


U.S. Government Agency - Mortgage Securities

17.7


CMOs and Other Mortgage Related Securities

2.6


Foreign Government and Government Agency Obligations

1.4


Preferred Securities

1.3


Asset-Backed Securities

0.4


Short-Term Investments and Net Other Assets (Liabilities)

1.1




ASSET ALLOCATION (% of Fund's net assets)


&#160;



&#160;

Corporate Bonds - 40.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

U.S. Treasury Obligations - 35.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

U.S. Government Agency - Mortgage Securities - 17.7


&#160;

CMOs and Other Mortgage Related Securities - 2.6


&#160;

Foreign Government and Government Agency Obligations - 1.4


&#160;

Preferred Securities - 1.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Asset-Backed Securities - 0.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Short-Term Investments and Net Other Assets (Liabilities) - 1.1


&#160;






United States

79.6


United Kingdom

4.4


Germany

3.1


Netherlands

2.3


Italy

2.0


Canada

1.5


Ireland

1.3


Japan

1.1


Luxembourg

1.0


Others

3.7




GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

United States - 79.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

United Kingdom - 4.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Germany - 3.1&#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;

Netherlands - 2.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Italy - 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;&#160;


&#160;

Canada - 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;

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;

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;

Luxembourg - 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;

Others - 3.7&#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;
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    <oef:PctOfNav
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    <oef:PctOfNav
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    <oef:PctOfNav
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    <oef:LargestHoldingsTableTextBlock contextRef="C000227906_ClassMember" id="ixv-18350">TOP HOLDINGS(% of Fund's net assets)

&#160;

&#160;


US Treasury Notes

23.7


&#160;


US Treasury Bonds

11.3


&#160;


Freddie Mac Gold Pool

11.3


&#160;


Fannie Mae Mortgage pass-thru certificates

6.0


&#160;


Freddie Mac Multifamily Structured pass-thru certificates

2.3


&#160;


Morgan Stanley

1.8


&#160;


JPMorgan Chase &amp; Co

1.3


&#160;


AES Corp/The

1.0


&#160;


Consolidated Edison Co of New York Inc

1.0


&#160;


NatWest Group PLC

0.9


&#160;


&#160;

60.6

&#160;



</oef:LargestHoldingsTableTextBlock>
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      decimals="INF"
      id="ixv-308266"
      unitRef="pure">0.237</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-308267"
      unitRef="pure">0.113</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-308268"
      unitRef="pure">0.113</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-308269"
      unitRef="pure">0.060</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-308270"
      unitRef="pure">0.023</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-308271"
      unitRef="pure">0.018</oef:PctOfNav>
    <oef:PctOfNav
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      id="ixv-308272"
      unitRef="pure">0.013</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
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      unitRef="pure">0.010</oef:PctOfNav>
    <oef:PctOfNav
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      unitRef="pure">0.009</oef:PctOfNav>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-18521">2026-08-31</dei:DocumentPeriodEndDate>
    <oef:FundName contextRef="C000227901_ClassMember" id="ixv-18533">Fidelity&#xae; Environmental Bond Fund</oef:FundName>
    <oef:ClassName contextRef="C000227901_ClassMember" id="ixv-18536">Fidelity Advisor&#xae; Environmental Bond Fund Class M</oef:ClassName>
    <dei:TradingSymbol contextRef="C000227901_ClassMember" id="ixv-18540">FEBEX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000227901_ClassMember" id="ixv-18559">This annual shareholder report contains information about Fidelity&#xae; Environmental Bond Fund for the period September 1, 2025 to August 31, 2026.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000227901_ClassMember" id="ixv-18561">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000227901_ClassMember" id="ixv-18566">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="C000227901_ClassMember" id="ixv-18568">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000227901_ClassMember" id="ixv-18571">1-877-208-0098</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000227901_ClassMember" id="ixv-18574">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000227901_ClassMember" id="ixv-18581">&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;67&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;0.67&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="C000227901_ClassMember"
      decimals="0"
      id="ixv-308276"
      unitRef="usd">67</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000227901_ClassMember"
      decimals="INF"
      id="ixv-308277"
      unitRef="pure">0.0067</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000227901_ClassMember" id="ixv-18624">&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&#160; &#160;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, an underweight in mortgage-backed securities detracted from the fund's performance versus the benchmark Bloomberg U.S. Aggregate Bond 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;The fund's yield-curve positioning also hurt.&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, positioning among investment-grade corporate bonds, particularly above-benchmark exposure to financials and security selection among industrials, contributed to 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;The fund's use of derivatives and currency contracts to hedge certain aspects of the portfolio's global holdings 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;Notable changes over the past 12 months included decreasing exposure to U.S. Treasurys and increasing the allocations to corporate-backed bonds and mortgage-backed securities in the second half of the period.&lt;/span&gt;&lt;/div&gt;
&lt;div&gt;&lt;span style="font-size:12px;"&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;/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="C000227901_ClassMember" id="ixv-18653">How did the Fund perform over the life of Fund?

 &#160;&#160;
CUMULATIVE PERFORMANCE
June 15, 2021 through August 31, 2026. 
Initial investment of $10,000&#160;and the current sales charge was paid.
Class M


$9,600

$9,706


$8,466


$8,357


$8,970


$9,224



Bloomberg MSCI Global Green USD Bond Index (Hedged USD)


$10,000

$10,120


$8,921


$8,966


$9,691


$10,139



Bloomberg U.S. Aggregate Bond Index


$10,000

$10,126


$8,960


$8,853


$9,499


$9,796



&#160;

2021

2022

2023

2024

2025

2026









&#160;
</oef:LineGraphTableTextBlock>
    <oef:LineGraphAndTableMeasureName contextRef="C000227901_LG_ClassMember_6YR" id="ixv-18674">&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="C000227901_ClassMember_AsOf_2021"
      decimals="0"
      id="ixv-308278"
      unitRef="usd">9600</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000227901_ClassMember_AsOf_2022"
      decimals="0"
      id="ixv-308279"
      unitRef="usd">9706</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000227901_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-308280"
      unitRef="usd">8466</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000227901_ClassMember_AsOf_2024"
      decimals="0"
      id="ixv-308281"
      unitRef="usd">8357</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000227901_ClassMember_AsOf_2025"
      decimals="0"
      id="ixv-308282"
      unitRef="usd">8970</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000227901_ClassMember_AsOf_2026"
      decimals="0"
      id="ixv-308283"
      unitRef="usd">9224</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000227901_LG_1_AdditionalIndexMember_6YR"
      id="ixv-18703">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg MSCI Global Green USD Bond Index (Hedged USD)&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000227901_1_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-308284"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000227901_1_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-308285"
      unitRef="usd">10120</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000227901_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-308286"
      unitRef="usd">8921</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000227901_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-308287"
      unitRef="usd">8966</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000227901_1_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-308288"
      unitRef="usd">9691</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000227901_1_AdditionalIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-308289"
      unitRef="usd">10139</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000227901_LG_2_AdditionalIndexMember_6YR"
      id="ixv-18732">&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="C000227901_2_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-308290"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000227901_2_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-308291"
      unitRef="usd">10126</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000227901_2_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-308292"
      unitRef="usd">8960</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000227901_2_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-308293"
      unitRef="usd">8853</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000227901_2_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-308294"
      unitRef="usd">9499</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000227901_2_AdditionalIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-308295"
      unitRef="usd">9796</oef:AccmVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000227901_ClassMember" id="ixv-18798">AVERAGE ANNUAL TOTAL RETURNS:

&#160;

1 Year

5 Year

Life of Fund&#160;A


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

-2.76%

-1.57%


-1.29%


Class M (without 4.00% sales charge)

1.29%

-0.76%

-0.52%


Bloomberg MSCI Global Green USD Bond Index (Hedged USD)

2.39%


0.51%


0.72%


Bloomberg U.S. Aggregate Bond Index

1.89%


-0.29%


-0.04%




A&#160; &#160;From June 15, 2021

&#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="C000227901_ClassMember_1YR"
      decimals="INF"
      id="ixv-308296"
      unitRef="pure">-0.0276</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000227901_ClassMember_5YR"
      decimals="INF"
      id="ixv-308297"
      unitRef="pure">-0.0157</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000227901_ClassMember_2025-09-01_2026-08-31"
      decimals="INF"
      id="ixv-308298"
      unitRef="pure">-0.0129</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000227901_NoLoadClassMember_1YR"
      decimals="INF"
      id="ixv-308299"
      unitRef="pure">0.0129</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000227901_NoLoadClassMember_5YR"
      decimals="INF"
      id="ixv-308300"
      unitRef="pure">-0.0076</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000227901_NoLoadClassMember_2025-09-01_2026-08-31"
      decimals="INF"
      id="ixv-308301"
      unitRef="pure">-0.0052</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000227901_0_AdditionalIndexMember_1YR"
      decimals="INF"
      id="ixv-308302"
      unitRef="pure">0.0239</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000227901_0_AdditionalIndexMember_5YR"
      decimals="INF"
      id="ixv-308303"
      unitRef="pure">0.0051</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000227901_0_AdditionalIndexMember_LOC"
      decimals="INF"
      id="ixv-308304"
      unitRef="pure">0.0072</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000227901_1_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-308305"
      unitRef="pure">0.0189</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000227901_1_BBIndexMember_5YR"
      decimals="INF"
      id="ixv-308306"
      unitRef="pure">-0.0029</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000227901_1_BBIndexMember_LOC"
      decimals="INF"
      id="ixv-308307"
      unitRef="pure">-0.0004</oef:AvgAnnlRtrPct>
    <oef:PerfInceptionDate
      contextRef="C000227901_Perf_2021-06-15_ClassMember"
      id="ixv-18889">2021-06-15</oef:PerfInceptionDate>
    <oef:UpdPerfInfoLocationTextBlock contextRef="C000227901_ClassMember" id="ixv-18899">&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="C000227901_ClassMember" id="ixv-18911">&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="C000227901_ClassMember" id="ixv-18915">&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="C000227901_ClassMember" id="ixv-18921">&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;$&lt;/span&gt;35,022,546&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;216&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;153,454&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;67&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

52.7


AAA

0.7


AA

0.6


A

15.4


BBB

22.8


BB

3.3


Not Rated

3.4


Short-Term Investments and Net Other Assets (Liabilities)

1.1




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

U.S. Government and U.S. Government Agency Obligations - 52.7


&#160;

AAA - 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;

AA - 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;&#160;&#160;


&#160;

A - 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;&#160;


&#160;

BBB - 22.8&#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;

BB - 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;&#160;


&#160;

Not Rated - 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;

Short-Term Investments and Net Other Assets (Liabilities) - 1.1


&#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

40.5


U.S. Treasury Obligations

35.0


U.S. Government Agency - Mortgage Securities

17.7


CMOs and Other Mortgage Related Securities

2.6


Foreign Government and Government Agency Obligations

1.4


Preferred Securities

1.3


Asset-Backed Securities

0.4


Short-Term Investments and Net Other Assets (Liabilities)

1.1




ASSET ALLOCATION (% of Fund's net assets)


&#160;



&#160;

Corporate Bonds - 40.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

U.S. Treasury Obligations - 35.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

U.S. Government Agency - Mortgage Securities - 17.7


&#160;

CMOs and Other Mortgage Related Securities - 2.6


&#160;

Foreign Government and Government Agency Obligations - 1.4


&#160;

Preferred Securities - 1.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Asset-Backed Securities - 0.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Short-Term Investments and Net Other Assets (Liabilities) - 1.1


&#160;






United States

79.6


United Kingdom

4.4


Germany

3.1


Netherlands

2.3


Italy

2.0


Canada

1.5


Ireland

1.3


Japan

1.1


Luxembourg

1.0


Others

3.7




GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

United States - 79.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

United Kingdom - 4.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Germany - 3.1&#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;

Netherlands - 2.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Italy - 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;&#160;


&#160;

Canada - 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;

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;

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;

Luxembourg - 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;

Others - 3.7&#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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    <oef:PctOfNav
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    <oef:PctOfNav
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    <oef:PctOfNav
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      id="ixv-308319"
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    <oef:PctOfNav
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    <oef:PctOfNav
      contextRef="C000227901_AA_USTreasuryObligations_Member"
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      id="ixv-308321"
      unitRef="pure">0.350</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227901_AA_USGovernmentAgencyMortgageSecurities_Member"
      decimals="INF"
      id="ixv-308322"
      unitRef="pure">0.177</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227901_AA_CMOsandOtherMortgageRelatedSecurities_Member"
      decimals="INF"
      id="ixv-308323"
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    <oef:PctOfNav
      contextRef="C000227901_AA_ForeignGovernmentandGovernmentAgencyObligations_Member"
      decimals="INF"
      id="ixv-308324"
      unitRef="pure">0.014</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227901_AA_PreferredSecurities_Member"
      decimals="INF"
      id="ixv-308325"
      unitRef="pure">0.013</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227901_AA_AssetBackedSecurities_Member"
      decimals="INF"
      id="ixv-308326"
      unitRef="pure">0.004</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-308327"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227901_GD_US_Member"
      decimals="INF"
      id="ixv-308328"
      unitRef="pure">0.796</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227901_GD_GB_Member"
      decimals="INF"
      id="ixv-308329"
      unitRef="pure">0.044</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227901_GD_DE_Member"
      decimals="INF"
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    <oef:PctOfNav
      contextRef="C000227901_GD_NL_Member"
      decimals="INF"
      id="ixv-308331"
      unitRef="pure">0.023</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227901_GD_IT_Member"
      decimals="INF"
      id="ixv-308332"
      unitRef="pure">0.020</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227901_GD_CA_Member"
      decimals="INF"
      id="ixv-308333"
      unitRef="pure">0.015</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227901_GD_IE_Member"
      decimals="INF"
      id="ixv-308334"
      unitRef="pure">0.013</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227901_GD_JP_Member"
      decimals="INF"
      id="ixv-308335"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227901_GD_LU_Member"
      decimals="INF"
      id="ixv-308336"
      unitRef="pure">0.010</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227901_GD_Other_Member"
      decimals="INF"
      id="ixv-308337"
      unitRef="pure">0.037</oef:PctOfNav>
    <oef:LargestHoldingsTableTextBlock contextRef="C000227901_ClassMember" id="ixv-19431">TOP HOLDINGS(% of Fund's net assets)

&#160;

&#160;


US Treasury Notes

23.7


&#160;


US Treasury Bonds

11.3


&#160;


Freddie Mac Gold Pool

11.3


&#160;


Fannie Mae Mortgage pass-thru certificates

6.0


&#160;


Freddie Mac Multifamily Structured pass-thru certificates

2.3


&#160;


Morgan Stanley

1.8


&#160;


JPMorgan Chase &amp; Co

1.3


&#160;


AES Corp/The

1.0


&#160;


Consolidated Edison Co of New York Inc

1.0


&#160;


NatWest Group PLC

0.9


&#160;


&#160;

60.6

&#160;



</oef:LargestHoldingsTableTextBlock>
    <oef:PctOfNav
      contextRef="C000227901_TH_0_Member"
      decimals="INF"
      id="ixv-308338"
      unitRef="pure">0.237</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227901_TH_1_Member"
      decimals="INF"
      id="ixv-308339"
      unitRef="pure">0.113</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227901_TH_2_Member"
      decimals="INF"
      id="ixv-308340"
      unitRef="pure">0.113</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227901_TH_3_Member"
      decimals="INF"
      id="ixv-308341"
      unitRef="pure">0.060</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227901_TH_4_Member"
      decimals="INF"
      id="ixv-308342"
      unitRef="pure">0.023</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227901_TH_5_Member"
      decimals="INF"
      id="ixv-308343"
      unitRef="pure">0.018</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227901_TH_6_Member"
      decimals="INF"
      id="ixv-308344"
      unitRef="pure">0.013</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
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      unitRef="pure">0.010</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-308346"
      unitRef="pure">0.010</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-308347"
      unitRef="pure">0.009</oef:PctOfNav>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-19602">2026-08-31</dei:DocumentPeriodEndDate>
    <oef:FundName contextRef="C000227904_ClassMember" id="ixv-19614">Fidelity&#xae; Environmental Bond Fund</oef:FundName>
    <oef:ClassName contextRef="C000227904_ClassMember" id="ixv-19617">Fidelity Advisor&#xae; Environmental Bond Fund Class I</oef:ClassName>
    <dei:TradingSymbol contextRef="C000227904_ClassMember" id="ixv-19621">FEBFX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000227904_ClassMember" id="ixv-19640">This annual shareholder report contains information about Fidelity&#xae; Environmental Bond Fund for the period September 1, 2025 to August 31, 2026.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000227904_ClassMember" id="ixv-19642">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000227904_ClassMember" id="ixv-19647">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="C000227904_ClassMember" id="ixv-19649">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000227904_ClassMember" id="ixv-19652">1-877-208-0098</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000227904_ClassMember" id="ixv-19655">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000227904_ClassMember" id="ixv-19662">&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;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="C000227904_ClassMember"
      decimals="0"
      id="ixv-308348"
      unitRef="usd">45</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000227904_ClassMember"
      decimals="INF"
      id="ixv-308349"
      unitRef="pure">0.0045</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000227904_ClassMember" id="ixv-19705">&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&#160; &#160;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, an underweight in mortgage-backed securities detracted from the fund's performance versus the benchmark Bloomberg U.S. Aggregate Bond 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;The fund's yield-curve positioning also hurt.&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, positioning among investment-grade corporate bonds, particularly above-benchmark exposure to financials and security selection among industrials, contributed to 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;The fund's use of derivatives and currency contracts to hedge certain aspects of the portfolio's global holdings 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;Notable changes over the past 12 months included decreasing exposure to U.S. Treasurys and increasing the allocations to corporate-backed bonds and mortgage-backed securities in the second half of the period.&lt;/span&gt;&lt;/div&gt;
&lt;div&gt;&lt;span style="font-size:12px;"&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;/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="C000227904_ClassMember" id="ixv-19734">How did the Fund perform over the life of Fund?

 &#160;&#160;
CUMULATIVE PERFORMANCE
June 15, 2021 through August 31, 2026. 
Initial investment of $10,000.
Class I


$10,000

$10,116


$8,844


$8,740


$9,407


$9,695



Bloomberg MSCI Global Green USD Bond Index (Hedged USD)


$10,000

$10,120


$8,921


$8,966


$9,691


$10,139



Bloomberg U.S. Aggregate Bond Index


$10,000

$10,126


$8,960


$8,853


$9,499


$9,796



&#160;

2021

2022

2023

2024

2025

2026









&#160;
</oef:LineGraphTableTextBlock>
    <oef:LineGraphAndTableMeasureName contextRef="C000227904_LG_ClassMember_6YR" id="ixv-19753">&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="C000227904_ClassMember_AsOf_2021"
      decimals="0"
      id="ixv-308350"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000227904_ClassMember_AsOf_2022"
      decimals="0"
      id="ixv-308351"
      unitRef="usd">10116</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000227904_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-308352"
      unitRef="usd">8844</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000227904_ClassMember_AsOf_2024"
      decimals="0"
      id="ixv-308353"
      unitRef="usd">8740</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000227904_ClassMember_AsOf_2025"
      decimals="0"
      id="ixv-308354"
      unitRef="usd">9407</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000227904_ClassMember_AsOf_2026"
      decimals="0"
      id="ixv-308355"
      unitRef="usd">9695</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000227904_LG_1_AdditionalIndexMember_6YR"
      id="ixv-19782">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg MSCI Global Green USD Bond Index (Hedged USD)&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000227904_1_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-308356"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000227904_1_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-308357"
      unitRef="usd">10120</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000227904_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-308358"
      unitRef="usd">8921</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000227904_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-308359"
      unitRef="usd">8966</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000227904_1_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-308360"
      unitRef="usd">9691</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000227904_1_AdditionalIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-308361"
      unitRef="usd">10139</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000227904_LG_2_AdditionalIndexMember_6YR"
      id="ixv-19811">&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="C000227904_2_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-308362"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000227904_2_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-308363"
      unitRef="usd">10126</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000227904_2_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-308364"
      unitRef="usd">8960</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000227904_2_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-308365"
      unitRef="usd">8853</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000227904_2_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-308366"
      unitRef="usd">9499</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000227904_2_AdditionalIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-308367"
      unitRef="usd">9796</oef:AccmVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000227904_ClassMember" id="ixv-19877">AVERAGE ANNUAL TOTAL RETURNS:

&#160;

1 Year

5 Year

Life of Fund&#160;A


Class I

1.39%

-0.57%

-0.33%


Bloomberg MSCI Global Green USD Bond Index (Hedged USD)

2.39%


0.51%


0.72%


Bloomberg U.S. Aggregate Bond Index

1.89%


-0.29%


-0.04%




A&#160; &#160;From June 15, 2021

&#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="C000227904_NoLoadClassMember_1YR"
      decimals="INF"
      id="ixv-308368"
      unitRef="pure">0.0139</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000227904_NoLoadClassMember_5YR"
      decimals="INF"
      id="ixv-308369"
      unitRef="pure">-0.0057</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000227904_NoLoadClassMember_2025-09-01_2026-08-31"
      decimals="INF"
      id="ixv-308370"
      unitRef="pure">-0.0033</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000227904_0_AdditionalIndexMember_1YR"
      decimals="INF"
      id="ixv-308371"
      unitRef="pure">0.0239</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000227904_0_AdditionalIndexMember_5YR"
      decimals="INF"
      id="ixv-308372"
      unitRef="pure">0.0051</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000227904_0_AdditionalIndexMember_LOC"
      decimals="INF"
      id="ixv-308373"
      unitRef="pure">0.0072</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000227904_1_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-308374"
      unitRef="pure">0.0189</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000227904_1_BBIndexMember_5YR"
      decimals="INF"
      id="ixv-308375"
      unitRef="pure">-0.0029</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000227904_1_BBIndexMember_LOC"
      decimals="INF"
      id="ixv-308376"
      unitRef="pure">-0.0004</oef:AvgAnnlRtrPct>
    <oef:PerfInceptionDate
      contextRef="C000227904_Perf_2021-06-15_ClassMember"
      id="ixv-19950">2021-06-15</oef:PerfInceptionDate>
    <oef:UpdPerfInfoLocationTextBlock contextRef="C000227904_ClassMember" id="ixv-19960">&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="C000227904_ClassMember" id="ixv-19972">&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="C000227904_ClassMember" id="ixv-19976">&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="C000227904_ClassMember" id="ixv-19982">&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;$&lt;/span&gt;35,022,546&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;216&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;153,454&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;67&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="C000227904_InstantMember"
      decimals="0"
      id="ixv-308377"
      unitRef="usd">35022546</us-gaap:AssetsNet>
    <oef:HoldingsCount
      contextRef="C000227904_InstantMember"
      decimals="INF"
      id="ixv-308378"
      unitRef="holding">216</oef:HoldingsCount>
    <oef:AdvisoryFeesPaidAmt
      contextRef="C000227904_ClassMember"
      decimals="0"
      id="ixv-308379"
      unitRef="usd">153454</oef:AdvisoryFeesPaidAmt>
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      decimals="INF"
      id="ixv-308380"
      unitRef="pure">0.67</us-gaap:InvestmentCompanyPortfolioTurnover>
    <oef:HoldingsTableTextBlock contextRef="C000227904_ClassMember" id="ixv-20057">
&#160;
U.S. Government and U.S. Government Agency Obligations

52.7


AAA

0.7


AA

0.6


A

15.4


BBB

22.8


BB

3.3


Not Rated

3.4


Short-Term Investments and Net Other Assets (Liabilities)

1.1




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

U.S. Government and U.S. Government Agency Obligations - 52.7


&#160;

AAA - 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;

AA - 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;&#160;&#160;


&#160;

A - 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;&#160;


&#160;

BBB - 22.8&#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;

BB - 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;&#160;


&#160;

Not Rated - 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;

Short-Term Investments and Net Other Assets (Liabilities) - 1.1


&#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

40.5


U.S. Treasury Obligations

35.0


U.S. Government Agency - Mortgage Securities

17.7


CMOs and Other Mortgage Related Securities

2.6


Foreign Government and Government Agency Obligations

1.4


Preferred Securities

1.3


Asset-Backed Securities

0.4


Short-Term Investments and Net Other Assets (Liabilities)

1.1




ASSET ALLOCATION (% of Fund's net assets)


&#160;



&#160;

Corporate Bonds - 40.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

U.S. Treasury Obligations - 35.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

U.S. Government Agency - Mortgage Securities - 17.7


&#160;

CMOs and Other Mortgage Related Securities - 2.6


&#160;

Foreign Government and Government Agency Obligations - 1.4


&#160;

Preferred Securities - 1.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Asset-Backed Securities - 0.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Short-Term Investments and Net Other Assets (Liabilities) - 1.1


&#160;






United States

79.6


United Kingdom

4.4


Germany

3.1


Netherlands

2.3


Italy

2.0


Canada

1.5


Ireland

1.3


Japan

1.1


Luxembourg

1.0


Others

3.7




GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

United States - 79.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

United Kingdom - 4.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Germany - 3.1&#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;

Netherlands - 2.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Italy - 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;&#160;


&#160;

Canada - 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;

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;

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;

Luxembourg - 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;

Others - 3.7&#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="C000227904_QD_USGovernmentandUSGovernmentAgencyObligations_Member"
      decimals="INF"
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    <oef:PctOfNav
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    <oef:PctOfNav
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    <oef:PctOfNav
      contextRef="C000227904_QD_A_Member"
      decimals="INF"
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      unitRef="pure">0.154</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227904_QD_BBB_Member"
      decimals="INF"
      id="ixv-308385"
      unitRef="pure">0.228</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-308386"
      unitRef="pure">0.033</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227904_QD_NotRated_Member"
      decimals="INF"
      id="ixv-308387"
      unitRef="pure">0.034</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227904_QD_ShortTermInvestmentsandNetOtherAssetsLiabilities_Member"
      decimals="INF"
      id="ixv-308388"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227904_AA_CorporateBonds_Member"
      decimals="INF"
      id="ixv-308389"
      unitRef="pure">0.405</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227904_AA_USTreasuryObligations_Member"
      decimals="INF"
      id="ixv-308390"
      unitRef="pure">0.350</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227904_AA_USGovernmentAgencyMortgageSecurities_Member"
      decimals="INF"
      id="ixv-308391"
      unitRef="pure">0.177</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227904_AA_CMOsandOtherMortgageRelatedSecurities_Member"
      decimals="INF"
      id="ixv-308392"
      unitRef="pure">0.026</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227904_AA_ForeignGovernmentandGovernmentAgencyObligations_Member"
      decimals="INF"
      id="ixv-308393"
      unitRef="pure">0.014</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227904_AA_PreferredSecurities_Member"
      decimals="INF"
      id="ixv-308394"
      unitRef="pure">0.013</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227904_AA_AssetBackedSecurities_Member"
      decimals="INF"
      id="ixv-308395"
      unitRef="pure">0.004</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227904_AA_ShortTermInvestmentsandNetOtherAssetsLiabilities_Member"
      decimals="INF"
      id="ixv-308396"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227904_GD_US_Member"
      decimals="INF"
      id="ixv-308397"
      unitRef="pure">0.796</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227904_GD_GB_Member"
      decimals="INF"
      id="ixv-308398"
      unitRef="pure">0.044</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227904_GD_DE_Member"
      decimals="INF"
      id="ixv-308399"
      unitRef="pure">0.031</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227904_GD_NL_Member"
      decimals="INF"
      id="ixv-308400"
      unitRef="pure">0.023</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227904_GD_IT_Member"
      decimals="INF"
      id="ixv-308401"
      unitRef="pure">0.020</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227904_GD_CA_Member"
      decimals="INF"
      id="ixv-308402"
      unitRef="pure">0.015</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227904_GD_IE_Member"
      decimals="INF"
      id="ixv-308403"
      unitRef="pure">0.013</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227904_GD_JP_Member"
      decimals="INF"
      id="ixv-308404"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227904_GD_LU_Member"
      decimals="INF"
      id="ixv-308405"
      unitRef="pure">0.010</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227904_GD_Other_Member"
      decimals="INF"
      id="ixv-308406"
      unitRef="pure">0.037</oef:PctOfNav>
    <oef:LargestHoldingsTableTextBlock contextRef="C000227904_ClassMember" id="ixv-20492">TOP HOLDINGS(% of Fund's net assets)

&#160;

&#160;


US Treasury Notes

23.7


&#160;


US Treasury Bonds

11.3


&#160;


Freddie Mac Gold Pool

11.3


&#160;


Fannie Mae Mortgage pass-thru certificates

6.0


&#160;


Freddie Mac Multifamily Structured pass-thru certificates

2.3


&#160;


Morgan Stanley

1.8


&#160;


JPMorgan Chase &amp; Co

1.3


&#160;


AES Corp/The

1.0


&#160;


Consolidated Edison Co of New York Inc

1.0


&#160;


NatWest Group PLC

0.9


&#160;


&#160;

60.6

&#160;



</oef:LargestHoldingsTableTextBlock>
    <oef:PctOfNav
      contextRef="C000227904_TH_0_Member"
      decimals="INF"
      id="ixv-308407"
      unitRef="pure">0.237</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227904_TH_1_Member"
      decimals="INF"
      id="ixv-308408"
      unitRef="pure">0.113</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227904_TH_2_Member"
      decimals="INF"
      id="ixv-308409"
      unitRef="pure">0.113</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227904_TH_3_Member"
      decimals="INF"
      id="ixv-308410"
      unitRef="pure">0.060</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227904_TH_4_Member"
      decimals="INF"
      id="ixv-308411"
      unitRef="pure">0.023</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227904_TH_5_Member"
      decimals="INF"
      id="ixv-308412"
      unitRef="pure">0.018</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227904_TH_6_Member"
      decimals="INF"
      id="ixv-308413"
      unitRef="pure">0.013</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227904_TH_7_Member"
      decimals="INF"
      id="ixv-308414"
      unitRef="pure">0.010</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227904_TH_8_Member"
      decimals="INF"
      id="ixv-308415"
      unitRef="pure">0.010</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227904_TH_9_Member"
      decimals="INF"
      id="ixv-308416"
      unitRef="pure">0.009</oef:PctOfNav>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-20663">2026-08-31</dei:DocumentPeriodEndDate>
    <oef:FundName contextRef="C000227905_ClassMember" id="ixv-20675">Fidelity&#xae; Environmental Bond Fund</oef:FundName>
    <oef:ClassName contextRef="C000227905_ClassMember" id="ixv-20678">Fidelity Advisor&#xae; Environmental Bond Fund Class C</oef:ClassName>
    <dei:TradingSymbol contextRef="C000227905_ClassMember" id="ixv-20682">FEBDX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000227905_ClassMember" id="ixv-20701">This annual shareholder report contains information about Fidelity&#xae; Environmental Bond Fund for the period September 1, 2025 to August 31, 2026.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000227905_ClassMember" id="ixv-20703">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000227905_ClassMember" id="ixv-20708">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="C000227905_ClassMember" id="ixv-20710">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000227905_ClassMember" id="ixv-20713">1-877-208-0098</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000227905_ClassMember" id="ixv-20716">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000227905_ClassMember" id="ixv-20723">&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;144&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;1.43&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="C000227905_ClassMember"
      decimals="0"
      id="ixv-308417"
      unitRef="usd">144</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000227905_ClassMember"
      decimals="INF"
      id="ixv-308418"
      unitRef="pure">0.0143</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000227905_ClassMember" id="ixv-20766">&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&#160; &#160;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, an underweight in mortgage-backed securities detracted from the fund's performance versus the benchmark Bloomberg U.S. Aggregate Bond 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;The fund's yield-curve positioning also hurt.&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, positioning among investment-grade corporate bonds, particularly above-benchmark exposure to financials and security selection among industrials, contributed to 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;The fund's use of derivatives and currency contracts to hedge certain aspects of the portfolio's global holdings 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;Notable changes over the past 12 months included decreasing exposure to U.S. Treasurys and increasing the allocations to corporate-backed bonds and mortgage-backed securities in the second half of the period.&lt;/span&gt;&lt;/div&gt;
&lt;div&gt;&lt;span style="font-size:12px;"&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;/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="C000227905_ClassMember" id="ixv-20795">How did the Fund perform over the life of Fund?

 &#160;&#160;
CUMULATIVE PERFORMANCE
June 15, 2021 through August 31, 2026. 
Initial investment of $10,000.
Class C


$10,000

$10,090


$8,736


$8,560


$9,129


$9,305



Bloomberg MSCI Global Green USD Bond Index (Hedged USD)


$10,000

$10,120


$8,921


$8,966


$9,691


$10,139



Bloomberg U.S. Aggregate Bond Index


$10,000

$10,126


$8,960


$8,853


$9,499


$9,796



&#160;

2021

2022

2023

2024

2025

2026









&#160;
</oef:LineGraphTableTextBlock>
    <oef:LineGraphAndTableMeasureName contextRef="C000227905_LG_ClassMember_6YR" id="ixv-20814">&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="C000227905_ClassMember_AsOf_2021"
      decimals="0"
      id="ixv-308419"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000227905_ClassMember_AsOf_2022"
      decimals="0"
      id="ixv-308420"
      unitRef="usd">10090</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000227905_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-308421"
      unitRef="usd">8736</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000227905_ClassMember_AsOf_2024"
      decimals="0"
      id="ixv-308422"
      unitRef="usd">8560</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000227905_ClassMember_AsOf_2025"
      decimals="0"
      id="ixv-308423"
      unitRef="usd">9129</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000227905_ClassMember_AsOf_2026"
      decimals="0"
      id="ixv-308424"
      unitRef="usd">9305</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000227905_LG_1_AdditionalIndexMember_6YR"
      id="ixv-20843">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg MSCI Global Green USD Bond Index (Hedged USD)&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000227905_1_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-308425"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000227905_1_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-308426"
      unitRef="usd">10120</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000227905_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-308427"
      unitRef="usd">8921</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000227905_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-308428"
      unitRef="usd">8966</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000227905_1_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-308429"
      unitRef="usd">9691</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000227905_1_AdditionalIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-308430"
      unitRef="usd">10139</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000227905_LG_2_AdditionalIndexMember_6YR"
      id="ixv-20872">&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="C000227905_2_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-308431"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000227905_2_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-308432"
      unitRef="usd">10126</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000227905_2_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-308433"
      unitRef="usd">8960</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000227905_2_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-308434"
      unitRef="usd">8853</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000227905_2_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-308435"
      unitRef="usd">9499</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000227905_2_AdditionalIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-308436"
      unitRef="usd">9796</oef:AccmVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000227905_ClassMember" id="ixv-20938">AVERAGE ANNUAL TOTAL RETURNS:

&#160;

1 Year

5 Year

Life of Fund&#160;A


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

-0.46%

-1.50%


-1.27%


Class C

0.52%

-1.50%

-1.27%


Bloomberg MSCI Global Green USD Bond Index (Hedged USD)

2.39%


0.51%


0.72%


Bloomberg U.S. Aggregate Bond Index

1.89%


-0.29%


-0.04%




A&#160; &#160;From June 15, 2021

&#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="C000227905_ClassMember_1YR"
      decimals="INF"
      id="ixv-308437"
      unitRef="pure">-0.0046</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000227905_ClassMember_5YR"
      decimals="INF"
      id="ixv-308438"
      unitRef="pure">-0.0150</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000227905_ClassMember_2025-09-01_2026-08-31"
      decimals="INF"
      id="ixv-308439"
      unitRef="pure">-0.0127</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000227905_NoLoadClassMember_1YR"
      decimals="INF"
      id="ixv-308440"
      unitRef="pure">0.0052</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000227905_NoLoadClassMember_5YR"
      decimals="INF"
      id="ixv-308441"
      unitRef="pure">-0.0150</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000227905_NoLoadClassMember_2025-09-01_2026-08-31"
      decimals="INF"
      id="ixv-308442"
      unitRef="pure">-0.0127</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000227905_0_AdditionalIndexMember_1YR"
      decimals="INF"
      id="ixv-308443"
      unitRef="pure">0.0239</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000227905_0_AdditionalIndexMember_5YR"
      decimals="INF"
      id="ixv-308444"
      unitRef="pure">0.0051</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000227905_0_AdditionalIndexMember_LOC"
      decimals="INF"
      id="ixv-308445"
      unitRef="pure">0.0072</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000227905_1_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-308446"
      unitRef="pure">0.0189</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000227905_1_BBIndexMember_5YR"
      decimals="INF"
      id="ixv-308447"
      unitRef="pure">-0.0029</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000227905_1_BBIndexMember_LOC"
      decimals="INF"
      id="ixv-308448"
      unitRef="pure">-0.0004</oef:AvgAnnlRtrPct>
    <oef:PerfInceptionDate
      contextRef="C000227905_Perf_2021-06-15_ClassMember"
      id="ixv-21030">2021-06-15</oef:PerfInceptionDate>
    <oef:UpdPerfInfoLocationTextBlock contextRef="C000227905_ClassMember" id="ixv-21040">&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="C000227905_ClassMember" id="ixv-21052">&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="C000227905_ClassMember" id="ixv-21056">&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="C000227905_ClassMember" id="ixv-21062">&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;$&lt;/span&gt;35,022,546&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;216&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;153,454&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;67&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="C000227905_InstantMember"
      decimals="0"
      id="ixv-308449"
      unitRef="usd">35022546</us-gaap:AssetsNet>
    <oef:HoldingsCount
      contextRef="C000227905_InstantMember"
      decimals="INF"
      id="ixv-308450"
      unitRef="holding">216</oef:HoldingsCount>
    <oef:AdvisoryFeesPaidAmt
      contextRef="C000227905_ClassMember"
      decimals="0"
      id="ixv-308451"
      unitRef="usd">153454</oef:AdvisoryFeesPaidAmt>
    <us-gaap:InvestmentCompanyPortfolioTurnover
      contextRef="C000227905_ClassMember"
      decimals="INF"
      id="ixv-308452"
      unitRef="pure">0.67</us-gaap:InvestmentCompanyPortfolioTurnover>
    <oef:HoldingsTableTextBlock contextRef="C000227905_ClassMember" id="ixv-21137">
&#160;
U.S. Government and U.S. Government Agency Obligations

52.7


AAA

0.7


AA

0.6


A

15.4


BBB

22.8


BB

3.3


Not Rated

3.4


Short-Term Investments and Net Other Assets (Liabilities)

1.1




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

U.S. Government and U.S. Government Agency Obligations - 52.7


&#160;

AAA - 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;

AA - 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;&#160;&#160;


&#160;

A - 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;&#160;


&#160;

BBB - 22.8&#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;

BB - 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;&#160;


&#160;

Not Rated - 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;

Short-Term Investments and Net Other Assets (Liabilities) - 1.1


&#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

40.5


U.S. Treasury Obligations

35.0


U.S. Government Agency - Mortgage Securities

17.7


CMOs and Other Mortgage Related Securities

2.6


Foreign Government and Government Agency Obligations

1.4


Preferred Securities

1.3


Asset-Backed Securities

0.4


Short-Term Investments and Net Other Assets (Liabilities)

1.1




ASSET ALLOCATION (% of Fund's net assets)


&#160;



&#160;

Corporate Bonds - 40.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

U.S. Treasury Obligations - 35.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

U.S. Government Agency - Mortgage Securities - 17.7


&#160;

CMOs and Other Mortgage Related Securities - 2.6


&#160;

Foreign Government and Government Agency Obligations - 1.4


&#160;

Preferred Securities - 1.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Asset-Backed Securities - 0.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Short-Term Investments and Net Other Assets (Liabilities) - 1.1


&#160;






United States

79.6


United Kingdom

4.4


Germany

3.1


Netherlands

2.3


Italy

2.0


Canada

1.5


Ireland

1.3


Japan

1.1


Luxembourg

1.0


Others

3.7




GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

United States - 79.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

United Kingdom - 4.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Germany - 3.1&#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;

Netherlands - 2.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Italy - 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;&#160;


&#160;

Canada - 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;

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;

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;

Luxembourg - 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;

Others - 3.7&#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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      id="ixv-308468"
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      decimals="INF"
      id="ixv-308472"
      unitRef="pure">0.023</oef:PctOfNav>
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      id="ixv-308473"
      unitRef="pure">0.020</oef:PctOfNav>
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      unitRef="pure">0.015</oef:PctOfNav>
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      decimals="INF"
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      unitRef="pure">0.013</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
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    <oef:PctOfNav
      contextRef="C000227905_GD_LU_Member"
      decimals="INF"
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      unitRef="pure">0.010</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-308478"
      unitRef="pure">0.037</oef:PctOfNav>
    <oef:LargestHoldingsTableTextBlock contextRef="C000227905_ClassMember" id="ixv-21572">TOP HOLDINGS(% of Fund's net assets)

&#160;

&#160;


US Treasury Notes

23.7


&#160;


US Treasury Bonds

11.3


&#160;


Freddie Mac Gold Pool

11.3


&#160;


Fannie Mae Mortgage pass-thru certificates

6.0


&#160;


Freddie Mac Multifamily Structured pass-thru certificates

2.3


&#160;


Morgan Stanley

1.8


&#160;


JPMorgan Chase &amp; Co

1.3


&#160;


AES Corp/The

1.0


&#160;


Consolidated Edison Co of New York Inc

1.0


&#160;


NatWest Group PLC

0.9


&#160;


&#160;

60.6

&#160;



</oef:LargestHoldingsTableTextBlock>
    <oef:PctOfNav
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      id="ixv-308479"
      unitRef="pure">0.237</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227905_TH_1_Member"
      decimals="INF"
      id="ixv-308480"
      unitRef="pure">0.113</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227905_TH_2_Member"
      decimals="INF"
      id="ixv-308481"
      unitRef="pure">0.113</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227905_TH_3_Member"
      decimals="INF"
      id="ixv-308482"
      unitRef="pure">0.060</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227905_TH_4_Member"
      decimals="INF"
      id="ixv-308483"
      unitRef="pure">0.023</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227905_TH_5_Member"
      decimals="INF"
      id="ixv-308484"
      unitRef="pure">0.018</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227905_TH_6_Member"
      decimals="INF"
      id="ixv-308485"
      unitRef="pure">0.013</oef:PctOfNav>
    <oef:PctOfNav
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      id="ixv-308486"
      unitRef="pure">0.010</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227905_TH_8_Member"
      decimals="INF"
      id="ixv-308487"
      unitRef="pure">0.010</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227905_TH_9_Member"
      decimals="INF"
      id="ixv-308488"
      unitRef="pure">0.009</oef:PctOfNav>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-21743">2026-08-31</dei:DocumentPeriodEndDate>
    <oef:FundName contextRef="C000227902_ClassMember" id="ixv-21755">Fidelity&#xae; Environmental Bond Fund</oef:FundName>
    <oef:ClassName contextRef="C000227902_ClassMember" id="ixv-21758">Fidelity Advisor&#xae; Environmental Bond Fund Class A</oef:ClassName>
    <dei:TradingSymbol contextRef="C000227902_ClassMember" id="ixv-21762">FEBBX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000227902_ClassMember" id="ixv-21781">This annual shareholder report contains information about Fidelity&#xae; Environmental Bond Fund for the period September 1, 2025 to August 31, 2026.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000227902_ClassMember" id="ixv-21783">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000227902_ClassMember" id="ixv-21788">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="C000227902_ClassMember" id="ixv-21790">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000227902_ClassMember" id="ixv-21793">1-877-208-0098</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000227902_ClassMember" id="ixv-21796">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000227902_ClassMember" id="ixv-21803">&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;70&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="C000227902_ClassMember"
      decimals="0"
      id="ixv-308489"
      unitRef="usd">70</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000227902_ClassMember"
      decimals="INF"
      id="ixv-308490"
      unitRef="pure">0.0070</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000227902_ClassMember" id="ixv-21846">&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&#160; &#160;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, an underweight in mortgage-backed securities detracted from the fund's performance versus the benchmark Bloomberg U.S. Aggregate Bond 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;The fund's yield-curve positioning also hurt.&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, positioning among investment-grade corporate bonds, particularly above-benchmark exposure to financials and security selection among industrials, contributed to 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;The fund's use of derivatives and currency contracts to hedge certain aspects of the portfolio's global holdings 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;Notable changes over the past 12 months included decreasing exposure to U.S. Treasurys and increasing the allocations to corporate-backed bonds and mortgage-backed securities in the second half of the period.&lt;/span&gt;&lt;/div&gt;
&lt;div&gt;&lt;span style="font-size:12px;"&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;/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="C000227902_ClassMember" id="ixv-21875">How did the Fund perform over the life of Fund?

 &#160;&#160;
CUMULATIVE PERFORMANCE
June 15, 2021 through August 31, 2026. 
Initial investment of $10,000&#160;and the current sales charge was paid.
Class A


$9,600

$9,706


$8,465


$8,355


$8,966


$9,219



Bloomberg MSCI Global Green USD Bond Index (Hedged USD)


$10,000

$10,120


$8,921


$8,966


$9,691


$10,139



Bloomberg U.S. Aggregate Bond Index


$10,000

$10,126


$8,960


$8,853


$9,499


$9,796



&#160;

2021

2022

2023

2024

2025

2026









&#160;
</oef:LineGraphTableTextBlock>
    <oef:LineGraphAndTableMeasureName contextRef="C000227902_LG_ClassMember_6YR" id="ixv-21896">&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="C000227902_ClassMember_AsOf_2021"
      decimals="0"
      id="ixv-308491"
      unitRef="usd">9600</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000227902_ClassMember_AsOf_2022"
      decimals="0"
      id="ixv-308492"
      unitRef="usd">9706</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000227902_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-308493"
      unitRef="usd">8465</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000227902_ClassMember_AsOf_2024"
      decimals="0"
      id="ixv-308494"
      unitRef="usd">8355</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000227902_ClassMember_AsOf_2025"
      decimals="0"
      id="ixv-308495"
      unitRef="usd">8966</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000227902_ClassMember_AsOf_2026"
      decimals="0"
      id="ixv-308496"
      unitRef="usd">9219</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000227902_LG_1_AdditionalIndexMember_6YR"
      id="ixv-21925">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg MSCI Global Green USD Bond Index (Hedged USD)&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000227902_1_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-308497"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000227902_1_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-308498"
      unitRef="usd">10120</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000227902_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-308499"
      unitRef="usd">8921</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000227902_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-308500"
      unitRef="usd">8966</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000227902_1_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-308501"
      unitRef="usd">9691</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000227902_1_AdditionalIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-308502"
      unitRef="usd">10139</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000227902_LG_2_AdditionalIndexMember_6YR"
      id="ixv-21954">&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="C000227902_2_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-308503"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000227902_2_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-308504"
      unitRef="usd">10126</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000227902_2_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-308505"
      unitRef="usd">8960</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000227902_2_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-308506"
      unitRef="usd">8853</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000227902_2_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-308507"
      unitRef="usd">9499</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000227902_2_AdditionalIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-308508"
      unitRef="usd">9796</oef:AccmVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000227902_ClassMember" id="ixv-22020">AVERAGE ANNUAL TOTAL RETURNS:

&#160;

1 Year

5 Year

Life of Fund&#160;A


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

-2.79%

-1.58%


-1.31%


Class A (without 4.00% sales charge)

1.26%

-0.78%

-0.54%


Bloomberg MSCI Global Green USD Bond Index (Hedged USD)

2.39%


0.51%


0.72%


Bloomberg U.S. Aggregate Bond Index

1.89%


-0.29%


-0.04%




A&#160; &#160;From June 15, 2021

&#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="C000227902_ClassMember_1YR"
      decimals="INF"
      id="ixv-308509"
      unitRef="pure">-0.0279</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000227902_ClassMember_5YR"
      decimals="INF"
      id="ixv-308510"
      unitRef="pure">-0.0158</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000227902_ClassMember_2025-09-01_2026-08-31"
      decimals="INF"
      id="ixv-308511"
      unitRef="pure">-0.0131</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000227902_NoLoadClassMember_1YR"
      decimals="INF"
      id="ixv-308512"
      unitRef="pure">0.0126</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000227902_NoLoadClassMember_5YR"
      decimals="INF"
      id="ixv-308513"
      unitRef="pure">-0.0078</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000227902_NoLoadClassMember_2025-09-01_2026-08-31"
      decimals="INF"
      id="ixv-308514"
      unitRef="pure">-0.0054</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000227902_0_AdditionalIndexMember_1YR"
      decimals="INF"
      id="ixv-308515"
      unitRef="pure">0.0239</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000227902_0_AdditionalIndexMember_5YR"
      decimals="INF"
      id="ixv-308516"
      unitRef="pure">0.0051</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000227902_0_AdditionalIndexMember_LOC"
      decimals="INF"
      id="ixv-308517"
      unitRef="pure">0.0072</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000227902_1_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-308518"
      unitRef="pure">0.0189</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000227902_1_BBIndexMember_5YR"
      decimals="INF"
      id="ixv-308519"
      unitRef="pure">-0.0029</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000227902_1_BBIndexMember_LOC"
      decimals="INF"
      id="ixv-308520"
      unitRef="pure">-0.0004</oef:AvgAnnlRtrPct>
    <oef:PerfInceptionDate
      contextRef="C000227902_Perf_2021-06-15_ClassMember"
      id="ixv-22111">2021-06-15</oef:PerfInceptionDate>
    <oef:UpdPerfInfoLocationTextBlock contextRef="C000227902_ClassMember" id="ixv-22121">&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="C000227902_ClassMember" id="ixv-22133">&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="C000227902_ClassMember" id="ixv-22137">&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="C000227902_ClassMember" id="ixv-22143">&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;$&lt;/span&gt;35,022,546&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;216&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;153,454&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;67&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="C000227902_InstantMember"
      decimals="0"
      id="ixv-308521"
      unitRef="usd">35022546</us-gaap:AssetsNet>
    <oef:HoldingsCount
      contextRef="C000227902_InstantMember"
      decimals="INF"
      id="ixv-308522"
      unitRef="holding">216</oef:HoldingsCount>
    <oef:AdvisoryFeesPaidAmt
      contextRef="C000227902_ClassMember"
      decimals="0"
      id="ixv-308523"
      unitRef="usd">153454</oef:AdvisoryFeesPaidAmt>
    <us-gaap:InvestmentCompanyPortfolioTurnover
      contextRef="C000227902_ClassMember"
      decimals="INF"
      id="ixv-308524"
      unitRef="pure">0.67</us-gaap:InvestmentCompanyPortfolioTurnover>
    <oef:HoldingsTableTextBlock contextRef="C000227902_ClassMember" id="ixv-22218">
&#160;
U.S. Government and U.S. Government Agency Obligations

52.7


AAA

0.7


AA

0.6


A

15.4


BBB

22.8


BB

3.3


Not Rated

3.4


Short-Term Investments and Net Other Assets (Liabilities)

1.1




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

U.S. Government and U.S. Government Agency Obligations - 52.7


&#160;

AAA - 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;

AA - 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;&#160;&#160;


&#160;

A - 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;&#160;


&#160;

BBB - 22.8&#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;

BB - 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;&#160;


&#160;

Not Rated - 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;

Short-Term Investments and Net Other Assets (Liabilities) - 1.1


&#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

40.5


U.S. Treasury Obligations

35.0


U.S. Government Agency - Mortgage Securities

17.7


CMOs and Other Mortgage Related Securities

2.6


Foreign Government and Government Agency Obligations

1.4


Preferred Securities

1.3


Asset-Backed Securities

0.4


Short-Term Investments and Net Other Assets (Liabilities)

1.1




ASSET ALLOCATION (% of Fund's net assets)


&#160;



&#160;

Corporate Bonds - 40.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

U.S. Treasury Obligations - 35.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

U.S. Government Agency - Mortgage Securities - 17.7


&#160;

CMOs and Other Mortgage Related Securities - 2.6


&#160;

Foreign Government and Government Agency Obligations - 1.4


&#160;

Preferred Securities - 1.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Asset-Backed Securities - 0.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Short-Term Investments and Net Other Assets (Liabilities) - 1.1


&#160;






United States

79.6


United Kingdom

4.4


Germany

3.1


Netherlands

2.3


Italy

2.0


Canada

1.5


Ireland

1.3


Japan

1.1


Luxembourg

1.0


Others

3.7




GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

United States - 79.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

United Kingdom - 4.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Germany - 3.1&#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;

Netherlands - 2.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Italy - 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;&#160;


&#160;

Canada - 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;

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;

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;

Luxembourg - 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;

Others - 3.7&#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
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      decimals="INF"
      id="ixv-308525"
      unitRef="pure">0.527</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227902_QD_AAA_Member"
      decimals="INF"
      id="ixv-308526"
      unitRef="pure">0.007</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-308527"
      unitRef="pure">0.006</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227902_QD_A_Member"
      decimals="INF"
      id="ixv-308528"
      unitRef="pure">0.154</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227902_QD_BBB_Member"
      decimals="INF"
      id="ixv-308529"
      unitRef="pure">0.228</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227902_QD_BB_Member"
      decimals="INF"
      id="ixv-308530"
      unitRef="pure">0.033</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227902_QD_NotRated_Member"
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      id="ixv-308531"
      unitRef="pure">0.034</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-308532"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227902_AA_CorporateBonds_Member"
      decimals="INF"
      id="ixv-308533"
      unitRef="pure">0.405</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227902_AA_USTreasuryObligations_Member"
      decimals="INF"
      id="ixv-308534"
      unitRef="pure">0.350</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227902_AA_USGovernmentAgencyMortgageSecurities_Member"
      decimals="INF"
      id="ixv-308535"
      unitRef="pure">0.177</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227902_AA_CMOsandOtherMortgageRelatedSecurities_Member"
      decimals="INF"
      id="ixv-308536"
      unitRef="pure">0.026</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227902_AA_ForeignGovernmentandGovernmentAgencyObligations_Member"
      decimals="INF"
      id="ixv-308537"
      unitRef="pure">0.014</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227902_AA_PreferredSecurities_Member"
      decimals="INF"
      id="ixv-308538"
      unitRef="pure">0.013</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227902_AA_AssetBackedSecurities_Member"
      decimals="INF"
      id="ixv-308539"
      unitRef="pure">0.004</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227902_AA_ShortTermInvestmentsandNetOtherAssetsLiabilities_Member"
      decimals="INF"
      id="ixv-308540"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227902_GD_US_Member"
      decimals="INF"
      id="ixv-308541"
      unitRef="pure">0.796</oef:PctOfNav>
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      decimals="INF"
      id="ixv-308542"
      unitRef="pure">0.044</oef:PctOfNav>
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      decimals="INF"
      id="ixv-308543"
      unitRef="pure">0.031</oef:PctOfNav>
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      contextRef="C000227902_GD_NL_Member"
      decimals="INF"
      id="ixv-308544"
      unitRef="pure">0.023</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227902_GD_IT_Member"
      decimals="INF"
      id="ixv-308545"
      unitRef="pure">0.020</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227902_GD_CA_Member"
      decimals="INF"
      id="ixv-308546"
      unitRef="pure">0.015</oef:PctOfNav>
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      contextRef="C000227902_GD_IE_Member"
      decimals="INF"
      id="ixv-308547"
      unitRef="pure">0.013</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227902_GD_JP_Member"
      decimals="INF"
      id="ixv-308548"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227902_GD_LU_Member"
      decimals="INF"
      id="ixv-308549"
      unitRef="pure">0.010</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227902_GD_Other_Member"
      decimals="INF"
      id="ixv-308550"
      unitRef="pure">0.037</oef:PctOfNav>
    <oef:LargestHoldingsTableTextBlock contextRef="C000227902_ClassMember" id="ixv-22653">TOP HOLDINGS(% of Fund's net assets)

&#160;

&#160;


US Treasury Notes

23.7


&#160;


US Treasury Bonds

11.3


&#160;


Freddie Mac Gold Pool

11.3


&#160;


Fannie Mae Mortgage pass-thru certificates

6.0


&#160;


Freddie Mac Multifamily Structured pass-thru certificates

2.3


&#160;


Morgan Stanley

1.8


&#160;


JPMorgan Chase &amp; Co

1.3


&#160;


AES Corp/The

1.0


&#160;


Consolidated Edison Co of New York Inc

1.0


&#160;


NatWest Group PLC

0.9


&#160;


&#160;

60.6

&#160;



</oef:LargestHoldingsTableTextBlock>
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      contextRef="C000227902_TH_0_Member"
      decimals="INF"
      id="ixv-308551"
      unitRef="pure">0.237</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227902_TH_1_Member"
      decimals="INF"
      id="ixv-308552"
      unitRef="pure">0.113</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227902_TH_2_Member"
      decimals="INF"
      id="ixv-308553"
      unitRef="pure">0.113</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227902_TH_3_Member"
      decimals="INF"
      id="ixv-308554"
      unitRef="pure">0.060</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227902_TH_4_Member"
      decimals="INF"
      id="ixv-308555"
      unitRef="pure">0.023</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227902_TH_5_Member"
      decimals="INF"
      id="ixv-308556"
      unitRef="pure">0.018</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227902_TH_6_Member"
      decimals="INF"
      id="ixv-308557"
      unitRef="pure">0.013</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227902_TH_7_Member"
      decimals="INF"
      id="ixv-308558"
      unitRef="pure">0.010</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227902_TH_8_Member"
      decimals="INF"
      id="ixv-308559"
      unitRef="pure">0.010</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000227902_TH_9_Member"
      decimals="INF"
      id="ixv-308560"
      unitRef="pure">0.009</oef:PctOfNav>
</xbrl>
