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            <startDate>2025-01-31</startDate>
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    <dei:EntityRegistrantName contextRef="Trust" id="ixv-138604">Fidelity Salem Street Trust</dei:EntityRegistrantName>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-97">2026-01-31</dei:DocumentPeriodEndDate>
    <oef:FundName contextRef="C000048850_ClassMember" id="ixv-109">Fidelity&#xae; Tax-Free Bond Fund</oef:FundName>
    <oef:ClassName contextRef="C000048850_ClassMember" id="ixv-112">Fidelity&#xae; Tax-Free Bond Fund</oef:ClassName>
    <dei:TradingSymbol contextRef="C000048850_ClassMember" id="ixv-116">FTABX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000048850_ClassMember" id="ixv-135">This annual shareholder report contains information about Fidelity&#xae; Tax-Free Bond Fund for the period February 1, 2025 to January 31, 2026.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000048850_ClassMember" id="ixv-137">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000048850_ClassMember" id="ixv-142">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="C000048850_ClassMember" id="ixv-144">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000048850_ClassMember" id="ixv-147">1-800-544-8544</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000048850_ClassMember" id="ixv-150">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000048850_ClassMember" id="ixv-157">&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 $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:51%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity&#xae; Tax-Free Bond Fund&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:21%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$ &lt;/span&gt;26&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:27%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;0.25&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:ExpensesTextBlock>
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    <oef:FactorsAffectingPerfTextBlock contextRef="C000048850_ClassMember" id="ixv-199">&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. tax-exempt municipal bonds notched a strong gain for the 12 months ending January 31, 2026, bolstered by a second-half rally driven by three policy interest-rate cuts by the Federal Reserve since September, moderating muni supply and firming investor demand.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Against this backdrop, the fund's "carry" advantage, meaning the higher earned income of its holdings, notably contributed to performance versus the Bloomberg 3+ Year Non-AMT Municipal 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;Yield-curve positioning, helped by an underweight in longer-term bonds, provided another relative performance boost as the yield curve steepened during the 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;In contrast, pricing factors detracted from relative performance. Fund holdings are priced by a third-party pricing service and validated daily by Fidelity Management &amp;amp; Research's fair-value processes. Securities within the index, however, are priced by the index provider. These two approaches employ somewhat different methodologies in estimating the prices of municipal securities, most of which trade infrequently.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity 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 exposure to municipal bonds issued by Walker County Development Authority (GA) tied to McLemore Hotel &amp;amp; Resort also detracted, as they slumped after a missed debt-service deposit eroded investor confidence in the project's revenue stability.&#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;During the year, the portfolio management team reduced the fund's exposure to 20+-year bonds and lower-quality securities, and pared back exposure to the health care and higher education sectors.&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="C000048850_ClassMember" id="ixv-223">How did the Fund perform over the past 10 years?

 &#160;&#160;
CUMULATIVE PERFORMANCE
January 31, 2016 through January 31, 2026. 
Initial investment of $25,000.
Fidelity&#xae; Tax-Free Bond Fund


$25,000

$24,921


$26,014


$26,818


$29,465


$30,626


$30,272


$28,946


$30,019


$30,721


$32,246



Bloomberg 3+ Year Non-AMT Municipal Bond Index


$25,000

$24,894


$25,873


$26,767


$29,283


$30,557


$29,921


$28,826


$29,667


$30,231


$31,672



Bloomberg Municipal Bond Index


$25,000

$24,930


$25,808


$26,651


$28,955


$30,117


$29,549


$28,589


$29,418


$30,031


$31,442



&#160;

2016

2017

2018

2019

2020

2021

2022

2023

2024

2025

2026









&#160;
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    <oef:LineGraphAndTableMeasureName
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      id="ixv-291">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg 3+ Year Non-AMT Municipal Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
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      id="ixv-340">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg Municipal Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
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    <oef:AccmVal
      contextRef="C000048850_2_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-143895"
      unitRef="usd">28589</oef:AccmVal>
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      contextRef="C000048850_2_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-143896"
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    <oef:AccmVal
      contextRef="C000048850_2_AdditionalIndexMember_AsOf_2025"
      decimals="0"
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      unitRef="usd">30031</oef:AccmVal>
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    <oef:AvgAnnlRtrTableTextBlock contextRef="C000048850_ClassMember" id="ixv-441">AVERAGE ANNUAL TOTAL RETURNS:

&#160;

1 Year

5 Year

10 Year


Fidelity&#xae; Tax-Free Bond Fund

4.96%

1.04%

2.58%


Bloomberg 3+ Year Non-AMT Municipal Bond Index

4.77%


0.72%


2.39%


Bloomberg Municipal Bond Index

4.70%


0.86%


2.32%




&#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.





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      id="ixv-143907"
      unitRef="pure">0.0232</oef:AvgAnnlRtrPct>
    <oef:UpdPerfInfoLocationTextBlock contextRef="C000048850_ClassMember" id="ixv-511">&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="C000048850_ClassMember" id="ixv-523">&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="C000048850_ClassMember" id="ixv-527">&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="C000048850_ClassMember" id="ixv-533">&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 January 31, 2026)&lt;/span&gt;&lt;/div&gt;
&lt;div&gt;&lt;span style="font-size:11px;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;table cellpadding="0" cellspacing="1" style="border-collapse:separate;border-style:none;margin:auto;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:63%; " valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:bold;"&gt;KEY FACTS&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt; &lt;span&gt;&#160;&lt;/span&gt;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fund Size&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;3,732,475,427&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;1,269&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;14,606,413&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;20&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;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;/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-143908"
      unitRef="usd">3732475427</us-gaap:AssetsNet>
    <oef:HoldingsCount
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      decimals="INF"
      id="ixv-143909"
      unitRef="holding">1269</oef:HoldingsCount>
    <oef:AdvisoryFeesPaidAmt
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      unitRef="usd">14606413</oef:AdvisoryFeesPaidAmt>
    <us-gaap:InvestmentCompanyPortfolioTurnover
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      decimals="INF"
      id="ixv-143911"
      unitRef="pure">0.20</us-gaap:InvestmentCompanyPortfolioTurnover>
    <oef:HoldingsTableTextBlock contextRef="C000048850_ClassMember" id="ixv-608">
&#160;
REVENUE SOURCES
 (% of Fund's net assets)


General Obligations

34.8

&#160;


Health Care

13.0

&#160;


Transportation

11.9

&#160;


Special Tax

11.4

&#160;


Electric Utilities

7.8

&#160;


Education

6.4

&#160;


Others(Individually Less Than 5%)

7.6

&#160;


92.9

&#160;


&#160;




&#160;
AAA

5.3


AA

37.9


A

37.5


BBB

6.6


BB

1.8


B

0.3


CCC,CC,C

0.1


Not Rated

3.4


Short-Term Investments and Net Other Assets (Liabilities)

7.1




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

AAA - 5.3&#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;

AA - 37.9&#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;

A - 37.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BBB - 6.6&#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;

BB - 1.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

B - 0.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

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


&#160;

Not Rated - 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) - 7.1


&#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;
TOP STATES
(% of Fund's net assets)


New York

10.6


Illinois

9.4


Texas

9.3


Alabama

6.4


New Jersey

5.8


&#160;

&#160;




&#160;
</oef:HoldingsTableTextBlock>
    <oef:PctOfNav
      contextRef="C000048850_RS_0_Member"
      decimals="INF"
      id="ixv-143912"
      unitRef="pure">0.348</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000048850_RS_1_Member"
      decimals="INF"
      id="ixv-143913"
      unitRef="pure">0.130</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000048850_RS_2_Member"
      decimals="INF"
      id="ixv-143914"
      unitRef="pure">0.119</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000048850_RS_3_Member"
      decimals="INF"
      id="ixv-143915"
      unitRef="pure">0.114</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000048850_RS_4_Member"
      decimals="INF"
      id="ixv-143916"
      unitRef="pure">0.078</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000048850_RS_5_Member"
      decimals="INF"
      id="ixv-143917"
      unitRef="pure">0.064</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000048850_RS_6_Member"
      decimals="INF"
      id="ixv-143918"
      unitRef="pure">0.076</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000048850_QD_AAA_Member"
      decimals="INF"
      id="ixv-143919"
      unitRef="pure">0.053</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000048850_QD_AA_Member"
      decimals="INF"
      id="ixv-143920"
      unitRef="pure">0.379</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000048850_QD_A_Member"
      decimals="INF"
      id="ixv-143921"
      unitRef="pure">0.375</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000048850_QD_BBB_Member"
      decimals="INF"
      id="ixv-143922"
      unitRef="pure">0.066</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000048850_QD_BB_Member"
      decimals="INF"
      id="ixv-143923"
      unitRef="pure">0.018</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000048850_QD_B_Member"
      decimals="INF"
      id="ixv-143924"
      unitRef="pure">0.003</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000048850_QD_CCCCCC_Member"
      decimals="INF"
      id="ixv-143925"
      unitRef="pure">0.001</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000048850_QD_NotRated_Member"
      decimals="INF"
      id="ixv-143926"
      unitRef="pure">0.034</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000048850_QD_ShortTermInvestmentsandNetOtherAssetsLiabilities_Member"
      decimals="INF"
      id="ixv-143927"
      unitRef="pure">0.071</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000048850_TS_0_Member"
      decimals="INF"
      id="ixv-143928"
      unitRef="pure">0.106</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000048850_TS_1_Member"
      decimals="INF"
      id="ixv-143929"
      unitRef="pure">0.094</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000048850_TS_2_Member"
      decimals="INF"
      id="ixv-143930"
      unitRef="pure">0.093</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000048850_TS_3_Member"
      decimals="INF"
      id="ixv-143931"
      unitRef="pure">0.064</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000048850_TS_4_Member"
      decimals="INF"
      id="ixv-143932"
      unitRef="pure">0.058</oef:PctOfNav>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-944">2026-01-31</dei:DocumentPeriodEndDate>
    <oef:FundName contextRef="C000235223_ClassMember" id="ixv-956">Fidelity&#xae; Sustainable Intermediate Municipal Income Fund</oef:FundName>
    <oef:ClassName contextRef="C000235223_ClassMember" id="ixv-959">Fidelity&#xae; Sustainable Intermediate Municipal Income Fund</oef:ClassName>
    <dei:TradingSymbol contextRef="C000235223_ClassMember" id="ixv-963">FSIKX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000235223_ClassMember" id="ixv-982">This annual shareholder report contains information about Fidelity&#xae; Sustainable Intermediate Municipal Income Fund for the period February 1, 2025 to January 31, 2026.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000235223_ClassMember" id="ixv-984">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000235223_ClassMember" id="ixv-989">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="C000235223_ClassMember" id="ixv-991">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000235223_ClassMember" id="ixv-994">1-800-544-8544</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000235223_ClassMember" id="ixv-997">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000235223_ClassMember" id="ixv-1004">&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 $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:51%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity&#xae; Sustainable Intermediate Municipal Income Fund&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:21%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$ &lt;/span&gt;38&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;0.37&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="C000235223_ClassMember"
      decimals="0"
      id="ixv-143933"
      unitRef="usd">38</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000235223_ClassMember"
      decimals="INF"
      id="ixv-143934"
      unitRef="pure">0.0037</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000235223_ClassMember" id="ixv-1046">&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. tax-exempt municipal bonds notched a strong gain for the 12 months ending January 31, 2026, bolstered by a second-half rally driven by three policy interest-rate cuts by the Federal Reserve since September, moderating muni supply and firming investor demand.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Against this backdrop, the fund's "carry" advantage, meaning its proportionately larger stake in higher-yielding bonds, contributed to performance versus the Bloomberg 3-15 Year Blend (2-17) 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;An overweight in the housing and utilities sectors further boosted 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 "positive convexity," meaning its exposure to non-callable and longer-call bonds, as well as the portfolio managers' active management of call risk, was also helpful.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;In contrast, the fund's overweight in health care bonds detracted from performance versus the 3-15 year index.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Underweights in certain higher-quality securities, including those in the state general obligation and the water &amp;amp; sewer sectors, also hurt.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Pricing factors crimped the relative result as well. Fund holdings are priced by a third-party pricing service and validated daily by Fidelity Management &amp;amp; Research's fair-value processes. Securities within the index, however, are priced by the index provider. These two approaches employ somewhat different methodologies in estimating the prices of municipal securities, most of which trade infrequently.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;During the year, the portfolio management team reduced the fund's exposure to the health care and higher education sectors and pared back exposure to lower-quality securities.&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 (ESG) 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;span style="line-height:13px;"&gt;&#160;&lt;/span&gt;&lt;div style="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;/div&gt;</oef:FactorsAffectingPerfTextBlock>
    <oef:LineGraphTableTextBlock contextRef="C000235223_ClassMember" id="ixv-1083">How did the Fund perform over the life of Fund?

 &#160;&#160;
CUMULATIVE PERFORMANCE
April 13, 2022 through January 31, 2026. 
Initial investment of $10,000.
Fidelity&#xae; Sustainable Intermediate Municipal Income Fund


$10,000

$10,344


$10,692


$10,936


$11,558



Bloomberg 3-15 Year Blend (2-17) Municipal Bond Index


$10,000

$10,276


$10,537


$10,731


$11,345



Bloomberg Municipal Bond Index


$10,000

$10,168


$10,463


$10,681


$11,183



&#160;

2022

2023

2024

2025

2026









&#160;
</oef:LineGraphTableTextBlock>
    <oef:LineGraphAndTableMeasureName contextRef="C000235223_LG_ClassMember_5YR" id="ixv-1102">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity&#xae; Sustainable Intermediate Municipal Income Fund&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000235223_ClassMember_AsOf_2022"
      decimals="0"
      id="ixv-143935"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235223_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-143936"
      unitRef="usd">10344</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235223_ClassMember_AsOf_2024"
      decimals="0"
      id="ixv-143937"
      unitRef="usd">10692</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235223_ClassMember_AsOf_2025"
      decimals="0"
      id="ixv-143938"
      unitRef="usd">10936</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235223_ClassMember_AsOf_2026"
      decimals="0"
      id="ixv-143939"
      unitRef="usd">11558</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000235223_LG_1_AdditionalIndexMember_5YR"
      id="ixv-1127">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg 3-15 Year Blend (2-17) Municipal Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000235223_1_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-143940"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235223_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-143941"
      unitRef="usd">10276</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235223_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-143942"
      unitRef="usd">10537</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235223_1_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-143943"
      unitRef="usd">10731</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235223_1_AdditionalIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-143944"
      unitRef="usd">11345</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000235223_LG_2_AdditionalIndexMember_5YR"
      id="ixv-1152">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg Municipal Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000235223_2_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-143945"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235223_2_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-143946"
      unitRef="usd">10168</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235223_2_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-143947"
      unitRef="usd">10463</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235223_2_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-143948"
      unitRef="usd">10681</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235223_2_AdditionalIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-143949"
      unitRef="usd">11183</oef:AccmVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000235223_ClassMember" id="ixv-1211">AVERAGE ANNUAL TOTAL RETURNS:

&#160;

1 Year

Life of Fund&#160;A


Fidelity&#xae; Sustainable Intermediate Municipal Income Fund

5.70%

3.88%


Bloomberg 3-15 Year Blend (2-17) Municipal Bond Index

5.72%


3.37%


Bloomberg Municipal Bond Index

4.70%


2.98%




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

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

&#160;


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





</oef:AvgAnnlRtrTableTextBlock>
    <oef:AvgAnnlRtrPct
      contextRef="C000235223_NoLoadClassMember_1YR"
      decimals="INF"
      id="ixv-143950"
      unitRef="pure">0.0570</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235223_NoLoadClassMember_2025-02-01_2026-01-31"
      decimals="INF"
      id="ixv-143951"
      unitRef="pure">0.0388</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235223_0_AdditionalIndexMember_1YR"
      decimals="INF"
      id="ixv-143952"
      unitRef="pure">0.0572</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235223_0_AdditionalIndexMember_LOC"
      decimals="INF"
      id="ixv-143953"
      unitRef="pure">0.0337</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235223_1_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-143954"
      unitRef="pure">0.0470</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235223_1_BBIndexMember_LOC"
      decimals="INF"
      id="ixv-143955"
      unitRef="pure">0.0298</oef:AvgAnnlRtrPct>
    <oef:PerfInceptionDate
      contextRef="C000235223_Perf_2022-04-13_ClassMember"
      id="ixv-1266">2022-04-13</oef:PerfInceptionDate>
    <oef:UpdPerfInfoLocationTextBlock contextRef="C000235223_ClassMember" id="ixv-1276">&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="C000235223_ClassMember" id="ixv-1288">&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="C000235223_ClassMember" id="ixv-1292">&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="C000235223_ClassMember" id="ixv-1298">&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 January 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;$&lt;/span&gt;26,103,588&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;271&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;88,312&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;16&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: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;/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="C000235223_InstantMember"
      decimals="0"
      id="ixv-143956"
      unitRef="usd">26103588</us-gaap:AssetsNet>
    <oef:HoldingsCount
      contextRef="C000235223_InstantMember"
      decimals="INF"
      id="ixv-143957"
      unitRef="holding">271</oef:HoldingsCount>
    <oef:AdvisoryFeesPaidAmt
      contextRef="C000235223_ClassMember"
      decimals="0"
      id="ixv-143958"
      unitRef="usd">88312</oef:AdvisoryFeesPaidAmt>
    <us-gaap:InvestmentCompanyPortfolioTurnover
      contextRef="C000235223_ClassMember"
      decimals="INF"
      id="ixv-143959"
      unitRef="pure">0.16</us-gaap:InvestmentCompanyPortfolioTurnover>
    <oef:HoldingsTableTextBlock contextRef="C000235223_ClassMember" id="ixv-1373">
&#160;
REVENUE SOURCES
 (% of Fund's net assets)


General Obligations

36.8

&#160;


Education

11.4

&#160;


Housing

11.1

&#160;


Health Care

9.5

&#160;


Electric Utilities

7.1

&#160;


Water &amp; Sewer

6.4

&#160;


Special Tax

6.2

&#160;


Transportation

5.0

&#160;


Others(Individually Less Than 5%)

3.1

&#160;


96.6

&#160;


&#160;




&#160;
AAA

12.4


AA

53.4


A

22.7


BBB

6.6


BB

1.3


Not Rated

0.2


Short-Term Investments and Net Other Assets (Liabilities)

3.4




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

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


&#160;

AA - 53.4&#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;

A - 22.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BBB - 6.6&#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;

BB - 1.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Not Rated - 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;

Short-Term Investments and Net Other Assets (Liabilities) - 3.4


&#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;
TOP STATES
(% of Fund's net assets)


Texas

13.8


Alabama

8.2


California

6.9


Georgia

5.4


Washington

5.3


&#160;

&#160;




&#160;
</oef:HoldingsTableTextBlock>
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    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-1701">2026-01-31</dei:DocumentPeriodEndDate>
    <oef:FundName contextRef="C000235227_ClassMember" id="ixv-1713">Fidelity&#xae; Sustainable Intermediate Municipal Income Fund</oef:FundName>
    <oef:ClassName contextRef="C000235227_ClassMember" id="ixv-1716">Fidelity Advisor&#xae; Sustainable Intermediate Municipal Income Fund Class Z</oef:ClassName>
    <dei:TradingSymbol contextRef="C000235227_ClassMember" id="ixv-1720">FASVX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000235227_ClassMember" id="ixv-1739">This annual shareholder report contains information about Fidelity&#xae; Sustainable Intermediate Municipal Income Fund for the period February 1, 2025 to January 31, 2026.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000235227_ClassMember" id="ixv-1741">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000235227_ClassMember" id="ixv-1746">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="C000235227_ClassMember" id="ixv-1748">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000235227_ClassMember" id="ixv-1751">1-877-208-0098</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000235227_ClassMember" id="ixv-1754">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000235227_ClassMember" id="ixv-1761">&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 $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:51%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Class Z&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:21%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$ &lt;/span&gt;32&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;0.31&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:ExpensesTextBlock>
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    <oef:ExpenseRatioPct
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      id="ixv-143982"
      unitRef="pure">0.0031</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000235227_ClassMember" id="ixv-1803">&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. tax-exempt municipal bonds notched a strong gain for the 12 months ending January 31, 2026, bolstered by a second-half rally driven by three policy interest-rate cuts by the Federal Reserve since September, moderating muni supply and firming investor demand.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Against this backdrop, the fund's "carry" advantage, meaning its proportionately larger stake in higher-yielding bonds, contributed to performance versus the Bloomberg 3-15 Year Blend (2-17) 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;An overweight in the housing and utilities sectors further boosted 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 "positive convexity," meaning its exposure to non-callable and longer-call bonds, as well as the portfolio managers' active management of call risk, was also helpful.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;In contrast, the fund's overweight in health care bonds detracted from performance versus the 3-15 year index.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Underweights in certain higher-quality securities, including those in the state general obligation and the water &amp;amp; sewer sectors, also hurt.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Pricing factors crimped the relative result as well. Fund holdings are priced by a third-party pricing service and validated daily by Fidelity Management &amp;amp; Research's fair-value processes. Securities within the index, however, are priced by the index provider. These two approaches employ somewhat different methodologies in estimating the prices of municipal securities, most of which trade infrequently.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;During the year, the portfolio management team reduced the fund's exposure to the health care and higher education sectors and pared back exposure to lower-quality securities.&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 (ESG) 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;span style="line-height:13px;"&gt;&#160;&lt;/span&gt;&lt;div style="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;/div&gt;</oef:FactorsAffectingPerfTextBlock>
    <oef:LineGraphTableTextBlock contextRef="C000235227_ClassMember" id="ixv-1840">How did the Fund perform over the life of Fund?

 &#160;&#160;
CUMULATIVE PERFORMANCE
April 13, 2022 through January 31, 2026. 
Initial investment of $10,000.
Class Z


$10,000

$10,349


$10,703


$10,954


$11,584



Bloomberg 3-15 Year Blend (2-17) Municipal Bond Index


$10,000

$10,276


$10,537


$10,731


$11,345



Bloomberg Municipal Bond Index


$10,000

$10,168


$10,463


$10,681


$11,183



&#160;

2022

2023

2024

2025

2026









&#160;
</oef:LineGraphTableTextBlock>
    <oef:LineGraphAndTableMeasureName contextRef="C000235227_LG_ClassMember_5YR" id="ixv-1859">&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="C000235227_ClassMember_AsOf_2022"
      decimals="0"
      id="ixv-143983"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235227_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-143984"
      unitRef="usd">10349</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235227_ClassMember_AsOf_2024"
      decimals="0"
      id="ixv-143985"
      unitRef="usd">10703</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235227_ClassMember_AsOf_2025"
      decimals="0"
      id="ixv-143986"
      unitRef="usd">10954</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235227_ClassMember_AsOf_2026"
      decimals="0"
      id="ixv-143987"
      unitRef="usd">11584</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000235227_LG_1_AdditionalIndexMember_5YR"
      id="ixv-1884">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg 3-15 Year Blend (2-17) Municipal Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000235227_1_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-143988"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235227_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-143989"
      unitRef="usd">10276</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235227_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-143990"
      unitRef="usd">10537</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235227_1_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-143991"
      unitRef="usd">10731</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235227_1_AdditionalIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-143992"
      unitRef="usd">11345</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000235227_LG_2_AdditionalIndexMember_5YR"
      id="ixv-1909">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg Municipal Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000235227_2_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-143993"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235227_2_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-143994"
      unitRef="usd">10168</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235227_2_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-143995"
      unitRef="usd">10463</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235227_2_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-143996"
      unitRef="usd">10681</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235227_2_AdditionalIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-143997"
      unitRef="usd">11183</oef:AccmVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000235227_ClassMember" id="ixv-1968">AVERAGE ANNUAL TOTAL RETURNS:

&#160;

1 Year

Life of Fund&#160;A


Class Z

5.76%

3.94%


Bloomberg 3-15 Year Blend (2-17) Municipal Bond Index

5.72%


3.37%


Bloomberg Municipal Bond Index

4.70%


2.98%




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

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

&#160;


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





</oef:AvgAnnlRtrTableTextBlock>
    <oef:AvgAnnlRtrPct
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      decimals="INF"
      id="ixv-143998"
      unitRef="pure">0.0576</oef:AvgAnnlRtrPct>
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      contextRef="C000235227_NoLoadClassMember_2025-02-01_2026-01-31"
      decimals="INF"
      id="ixv-143999"
      unitRef="pure">0.0394</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235227_0_AdditionalIndexMember_1YR"
      decimals="INF"
      id="ixv-144000"
      unitRef="pure">0.0572</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235227_0_AdditionalIndexMember_LOC"
      decimals="INF"
      id="ixv-144001"
      unitRef="pure">0.0337</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235227_1_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-144002"
      unitRef="pure">0.0470</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235227_1_BBIndexMember_LOC"
      decimals="INF"
      id="ixv-144003"
      unitRef="pure">0.0298</oef:AvgAnnlRtrPct>
    <oef:PerfInceptionDate
      contextRef="C000235227_Perf_2022-04-13_ClassMember"
      id="ixv-2023">2022-04-13</oef:PerfInceptionDate>
    <oef:UpdPerfInfoLocationTextBlock contextRef="C000235227_ClassMember" id="ixv-2033">&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="C000235227_ClassMember" id="ixv-2045">&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="C000235227_ClassMember" id="ixv-2049">&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="C000235227_ClassMember" id="ixv-2055">&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 January 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;$&lt;/span&gt;26,103,588&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;271&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;88,312&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;16&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: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;/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="C000235227_InstantMember"
      decimals="0"
      id="ixv-144004"
      unitRef="usd">26103588</us-gaap:AssetsNet>
    <oef:HoldingsCount
      contextRef="C000235227_InstantMember"
      decimals="INF"
      id="ixv-144005"
      unitRef="holding">271</oef:HoldingsCount>
    <oef:AdvisoryFeesPaidAmt
      contextRef="C000235227_ClassMember"
      decimals="0"
      id="ixv-144006"
      unitRef="usd">88312</oef:AdvisoryFeesPaidAmt>
    <us-gaap:InvestmentCompanyPortfolioTurnover
      contextRef="C000235227_ClassMember"
      decimals="INF"
      id="ixv-144007"
      unitRef="pure">0.16</us-gaap:InvestmentCompanyPortfolioTurnover>
    <oef:HoldingsTableTextBlock contextRef="C000235227_ClassMember" id="ixv-2130">
&#160;
REVENUE SOURCES
 (% of Fund's net assets)


General Obligations

36.8

&#160;


Education

11.4

&#160;


Housing

11.1

&#160;


Health Care

9.5

&#160;


Electric Utilities

7.1

&#160;


Water &amp; Sewer

6.4

&#160;


Special Tax

6.2

&#160;


Transportation

5.0

&#160;


Others(Individually Less Than 5%)

3.1

&#160;


96.6

&#160;


&#160;




&#160;
AAA

12.4


AA

53.4


A

22.7


BBB

6.6


BB

1.3


Not Rated

0.2


Short-Term Investments and Net Other Assets (Liabilities)

3.4




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

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


&#160;

AA - 53.4&#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;

A - 22.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BBB - 6.6&#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;

BB - 1.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Not Rated - 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;

Short-Term Investments and Net Other Assets (Liabilities) - 3.4


&#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;
TOP STATES
(% of Fund's net assets)


Texas

13.8


Alabama

8.2


California

6.9


Georgia

5.4


Washington

5.3


&#160;

&#160;




&#160;
</oef:HoldingsTableTextBlock>
    <oef:PctOfNav
      contextRef="C000235227_RS_0_Member"
      decimals="INF"
      id="ixv-144008"
      unitRef="pure">0.368</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235227_RS_1_Member"
      decimals="INF"
      id="ixv-144009"
      unitRef="pure">0.114</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235227_RS_2_Member"
      decimals="INF"
      id="ixv-144010"
      unitRef="pure">0.111</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235227_RS_3_Member"
      decimals="INF"
      id="ixv-144011"
      unitRef="pure">0.095</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235227_RS_4_Member"
      decimals="INF"
      id="ixv-144012"
      unitRef="pure">0.071</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235227_RS_5_Member"
      decimals="INF"
      id="ixv-144013"
      unitRef="pure">0.064</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235227_RS_6_Member"
      decimals="INF"
      id="ixv-144014"
      unitRef="pure">0.062</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235227_RS_7_Member"
      decimals="INF"
      id="ixv-144015"
      unitRef="pure">0.050</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235227_RS_8_Member"
      decimals="INF"
      id="ixv-144016"
      unitRef="pure">0.031</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235227_QD_AAA_Member"
      decimals="INF"
      id="ixv-144017"
      unitRef="pure">0.124</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235227_QD_AA_Member"
      decimals="INF"
      id="ixv-144018"
      unitRef="pure">0.534</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235227_QD_A_Member"
      decimals="INF"
      id="ixv-144019"
      unitRef="pure">0.227</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235227_QD_BBB_Member"
      decimals="INF"
      id="ixv-144020"
      unitRef="pure">0.066</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235227_QD_BB_Member"
      decimals="INF"
      id="ixv-144021"
      unitRef="pure">0.013</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235227_QD_NotRated_Member"
      decimals="INF"
      id="ixv-144022"
      unitRef="pure">0.002</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235227_QD_ShortTermInvestmentsandNetOtherAssetsLiabilities_Member"
      decimals="INF"
      id="ixv-144023"
      unitRef="pure">0.034</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235227_TS_0_Member"
      decimals="INF"
      id="ixv-144024"
      unitRef="pure">0.138</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235227_TS_1_Member"
      decimals="INF"
      id="ixv-144025"
      unitRef="pure">0.082</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235227_TS_2_Member"
      decimals="INF"
      id="ixv-144026"
      unitRef="pure">0.069</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235227_TS_3_Member"
      decimals="INF"
      id="ixv-144027"
      unitRef="pure">0.054</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235227_TS_4_Member"
      decimals="INF"
      id="ixv-144028"
      unitRef="pure">0.053</oef:PctOfNav>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-2458">2026-01-31</dei:DocumentPeriodEndDate>
    <oef:FundName contextRef="C000235224_ClassMember" id="ixv-2470">Fidelity&#xae; Sustainable Intermediate Municipal Income Fund</oef:FundName>
    <oef:ClassName contextRef="C000235224_ClassMember" id="ixv-2473">Fidelity Advisor&#xae; Sustainable Intermediate Municipal Income Fund Class M</oef:ClassName>
    <dei:TradingSymbol contextRef="C000235224_ClassMember" id="ixv-2477">FASLX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000235224_ClassMember" id="ixv-2496">This annual shareholder report contains information about Fidelity&#xae; Sustainable Intermediate Municipal Income Fund for the period February 1, 2025 to January 31, 2026.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000235224_ClassMember" id="ixv-2498">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000235224_ClassMember" id="ixv-2503">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="C000235224_ClassMember" id="ixv-2505">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000235224_ClassMember" id="ixv-2508">1-877-208-0098</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000235224_ClassMember" id="ixv-2511">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000235224_ClassMember" id="ixv-2518">&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 $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:51%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Class M&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:21%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$ &lt;/span&gt;64&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;0.62&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;/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="C000235224_ClassMember"
      decimals="0"
      id="ixv-144029"
      unitRef="usd">64</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000235224_ClassMember"
      decimals="INF"
      id="ixv-144030"
      unitRef="pure">0.0062</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000235224_ClassMember" id="ixv-2560">&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. tax-exempt municipal bonds notched a strong gain for the 12 months ending January 31, 2026, bolstered by a second-half rally driven by three policy interest-rate cuts by the Federal Reserve since September, moderating muni supply and firming investor demand.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Against this backdrop, the fund's "carry" advantage, meaning its proportionately larger stake in higher-yielding bonds, contributed to performance versus the Bloomberg 3-15 Year Blend (2-17) 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;An overweight in the housing and utilities sectors further boosted 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 "positive convexity," meaning its exposure to non-callable and longer-call bonds, as well as the portfolio managers' active management of call risk, was also helpful.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;In contrast, the fund's overweight in health care bonds detracted from performance versus the 3-15 year index.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Underweights in certain higher-quality securities, including those in the state general obligation and the water &amp;amp; sewer sectors, also hurt.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Pricing factors crimped the relative result as well. Fund holdings are priced by a third-party pricing service and validated daily by Fidelity Management &amp;amp; Research's fair-value processes. Securities within the index, however, are priced by the index provider. These two approaches employ somewhat different methodologies in estimating the prices of municipal securities, most of which trade infrequently.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;During the year, the portfolio management team reduced the fund's exposure to the health care and higher education sectors and pared back exposure to lower-quality securities.&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 (ESG) 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;span style="line-height:13px;"&gt;&#160;&lt;/span&gt;&lt;div style="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;/div&gt;</oef:FactorsAffectingPerfTextBlock>
    <oef:LineGraphTableTextBlock contextRef="C000235224_ClassMember" id="ixv-2597">How did the Fund perform over the life of Fund?

 &#160;&#160;
CUMULATIVE PERFORMANCE
April 13, 2022 through January 31, 2026. 
Initial investment of $10,000&#160;and the current sales charge was paid.
Class M


$9,600

$9,911


$10,218


$10,425


$10,981



Bloomberg 3-15 Year Blend (2-17) Municipal Bond Index


$10,000

$10,276


$10,537


$10,731


$11,345



Bloomberg Municipal Bond Index


$10,000

$10,168


$10,463


$10,681


$11,183



&#160;

2022

2023

2024

2025

2026









&#160;
</oef:LineGraphTableTextBlock>
    <oef:LineGraphAndTableMeasureName contextRef="C000235224_LG_ClassMember_5YR" id="ixv-2618">&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="C000235224_ClassMember_AsOf_2022"
      decimals="0"
      id="ixv-144031"
      unitRef="usd">9600</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235224_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-144032"
      unitRef="usd">9911</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235224_ClassMember_AsOf_2024"
      decimals="0"
      id="ixv-144033"
      unitRef="usd">10218</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235224_ClassMember_AsOf_2025"
      decimals="0"
      id="ixv-144034"
      unitRef="usd">10425</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235224_ClassMember_AsOf_2026"
      decimals="0"
      id="ixv-144035"
      unitRef="usd">10981</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000235224_LG_1_AdditionalIndexMember_5YR"
      id="ixv-2643">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg 3-15 Year Blend (2-17) Municipal Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000235224_1_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-144036"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235224_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-144037"
      unitRef="usd">10276</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235224_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-144038"
      unitRef="usd">10537</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235224_1_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-144039"
      unitRef="usd">10731</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235224_1_AdditionalIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-144040"
      unitRef="usd">11345</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000235224_LG_2_AdditionalIndexMember_5YR"
      id="ixv-2668">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg Municipal Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000235224_2_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-144041"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235224_2_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-144042"
      unitRef="usd">10168</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235224_2_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-144043"
      unitRef="usd">10463</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235224_2_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-144044"
      unitRef="usd">10681</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235224_2_AdditionalIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-144045"
      unitRef="usd">11183</oef:AccmVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000235224_ClassMember" id="ixv-2727">AVERAGE ANNUAL TOTAL RETURNS:

&#160;

1 Year

Life of Fund&#160;A


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

1.12%

2.49%


Class M (without 4.00% sales charge)

5.33%

3.59%


Bloomberg 3-15 Year Blend (2-17) Municipal Bond Index

5.72%


3.37%


Bloomberg Municipal Bond Index

4.70%


2.98%




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

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

&#160;


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





</oef:AvgAnnlRtrTableTextBlock>
    <oef:AvgAnnlRtrPct
      contextRef="C000235224_ClassMember_1YR"
      decimals="INF"
      id="ixv-144046"
      unitRef="pure">0.0112</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235224_ClassMember_2025-02-01_2026-01-31"
      decimals="INF"
      id="ixv-144047"
      unitRef="pure">0.0249</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235224_NoLoadClassMember_1YR"
      decimals="INF"
      id="ixv-144048"
      unitRef="pure">0.0533</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235224_NoLoadClassMember_2025-02-01_2026-01-31"
      decimals="INF"
      id="ixv-144049"
      unitRef="pure">0.0359</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235224_0_AdditionalIndexMember_1YR"
      decimals="INF"
      id="ixv-144050"
      unitRef="pure">0.0572</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235224_0_AdditionalIndexMember_LOC"
      decimals="INF"
      id="ixv-144051"
      unitRef="pure">0.0337</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235224_1_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-144052"
      unitRef="pure">0.0470</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235224_1_BBIndexMember_LOC"
      decimals="INF"
      id="ixv-144053"
      unitRef="pure">0.0298</oef:AvgAnnlRtrPct>
    <oef:PerfInceptionDate
      contextRef="C000235224_Perf_2022-04-13_ClassMember"
      id="ixv-2793">2022-04-13</oef:PerfInceptionDate>
    <oef:UpdPerfInfoLocationTextBlock contextRef="C000235224_ClassMember" id="ixv-2803">&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="C000235224_ClassMember" id="ixv-2815">&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="C000235224_ClassMember" id="ixv-2819">&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="C000235224_ClassMember" id="ixv-2825">&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 January 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;$&lt;/span&gt;26,103,588&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;271&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;88,312&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;16&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: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;/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="C000235224_InstantMember"
      decimals="0"
      id="ixv-144054"
      unitRef="usd">26103588</us-gaap:AssetsNet>
    <oef:HoldingsCount
      contextRef="C000235224_InstantMember"
      decimals="INF"
      id="ixv-144055"
      unitRef="holding">271</oef:HoldingsCount>
    <oef:AdvisoryFeesPaidAmt
      contextRef="C000235224_ClassMember"
      decimals="0"
      id="ixv-144056"
      unitRef="usd">88312</oef:AdvisoryFeesPaidAmt>
    <us-gaap:InvestmentCompanyPortfolioTurnover
      contextRef="C000235224_ClassMember"
      decimals="INF"
      id="ixv-144057"
      unitRef="pure">0.16</us-gaap:InvestmentCompanyPortfolioTurnover>
    <oef:HoldingsTableTextBlock contextRef="C000235224_ClassMember" id="ixv-2900">
&#160;
REVENUE SOURCES
 (% of Fund's net assets)


General Obligations

36.8

&#160;


Education

11.4

&#160;


Housing

11.1

&#160;


Health Care

9.5

&#160;


Electric Utilities

7.1

&#160;


Water &amp; Sewer

6.4

&#160;


Special Tax

6.2

&#160;


Transportation

5.0

&#160;


Others(Individually Less Than 5%)

3.1

&#160;


96.6

&#160;


&#160;




&#160;
AAA

12.4


AA

53.4


A

22.7


BBB

6.6


BB

1.3


Not Rated

0.2


Short-Term Investments and Net Other Assets (Liabilities)

3.4




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

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


&#160;

AA - 53.4&#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;

A - 22.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BBB - 6.6&#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;

BB - 1.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Not Rated - 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;

Short-Term Investments and Net Other Assets (Liabilities) - 3.4


&#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;
TOP STATES
(% of Fund's net assets)


Texas

13.8


Alabama

8.2


California

6.9


Georgia

5.4


Washington

5.3


&#160;

&#160;




&#160;
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    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-3228">2026-01-31</dei:DocumentPeriodEndDate>
    <oef:FundName contextRef="C000235226_ClassMember" id="ixv-3240">Fidelity&#xae; Sustainable Intermediate Municipal Income Fund</oef:FundName>
    <oef:ClassName contextRef="C000235226_ClassMember" id="ixv-3243">Fidelity Advisor&#xae; Sustainable Intermediate Municipal Income Fund Class I</oef:ClassName>
    <dei:TradingSymbol contextRef="C000235226_ClassMember" id="ixv-3247">FASUX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000235226_ClassMember" id="ixv-3266">This annual shareholder report contains information about Fidelity&#xae; Sustainable Intermediate Municipal Income Fund for the period February 1, 2025 to January 31, 2026.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000235226_ClassMember" id="ixv-3268">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000235226_ClassMember" id="ixv-3273">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="C000235226_ClassMember" id="ixv-3275">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000235226_ClassMember" id="ixv-3278">1-877-208-0098</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000235226_ClassMember" id="ixv-3281">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000235226_ClassMember" id="ixv-3288">&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 $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:51%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Class I&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:21%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$ &lt;/span&gt;38&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;0.37&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:ExpensesTextBlock>
    <oef:ExpensesPaidAmt
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      id="ixv-144079"
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    <oef:ExpenseRatioPct
      contextRef="C000235226_ClassMember"
      decimals="INF"
      id="ixv-144080"
      unitRef="pure">0.0037</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000235226_ClassMember" id="ixv-3330">&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. tax-exempt municipal bonds notched a strong gain for the 12 months ending January 31, 2026, bolstered by a second-half rally driven by three policy interest-rate cuts by the Federal Reserve since September, moderating muni supply and firming investor demand.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Against this backdrop, the fund's "carry" advantage, meaning its proportionately larger stake in higher-yielding bonds, contributed to performance versus the Bloomberg 3-15 Year Blend (2-17) 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;An overweight in the housing and utilities sectors further boosted 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 "positive convexity," meaning its exposure to non-callable and longer-call bonds, as well as the portfolio managers' active management of call risk, was also helpful.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;In contrast, the fund's overweight in health care bonds detracted from performance versus the 3-15 year index.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Underweights in certain higher-quality securities, including those in the state general obligation and the water &amp;amp; sewer sectors, also hurt.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Pricing factors crimped the relative result as well. Fund holdings are priced by a third-party pricing service and validated daily by Fidelity Management &amp;amp; Research's fair-value processes. Securities within the index, however, are priced by the index provider. These two approaches employ somewhat different methodologies in estimating the prices of municipal securities, most of which trade infrequently.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;During the year, the portfolio management team reduced the fund's exposure to the health care and higher education sectors and pared back exposure to lower-quality securities.&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 (ESG) 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;span style="line-height:13px;"&gt;&#160;&lt;/span&gt;&lt;div style="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;/div&gt;</oef:FactorsAffectingPerfTextBlock>
    <oef:LineGraphTableTextBlock contextRef="C000235226_ClassMember" id="ixv-3367">How did the Fund perform over the life of Fund?

 &#160;&#160;
CUMULATIVE PERFORMANCE
April 13, 2022 through January 31, 2026. 
Initial investment of $10,000.
Class I


$10,000

$10,344


$10,691


$10,935


$11,558



Bloomberg 3-15 Year Blend (2-17) Municipal Bond Index


$10,000

$10,276


$10,537


$10,731


$11,345



Bloomberg Municipal Bond Index


$10,000

$10,168


$10,463


$10,681


$11,183



&#160;

2022

2023

2024

2025

2026









&#160;
</oef:LineGraphTableTextBlock>
    <oef:LineGraphAndTableMeasureName contextRef="C000235226_LG_ClassMember_5YR" id="ixv-3386">&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="C000235226_ClassMember_AsOf_2022"
      decimals="0"
      id="ixv-144081"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235226_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-144082"
      unitRef="usd">10344</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235226_ClassMember_AsOf_2024"
      decimals="0"
      id="ixv-144083"
      unitRef="usd">10691</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235226_ClassMember_AsOf_2025"
      decimals="0"
      id="ixv-144084"
      unitRef="usd">10935</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235226_ClassMember_AsOf_2026"
      decimals="0"
      id="ixv-144085"
      unitRef="usd">11558</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000235226_LG_1_AdditionalIndexMember_5YR"
      id="ixv-3411">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg 3-15 Year Blend (2-17) Municipal Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000235226_1_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-144086"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235226_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-144087"
      unitRef="usd">10276</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235226_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-144088"
      unitRef="usd">10537</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235226_1_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-144089"
      unitRef="usd">10731</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235226_1_AdditionalIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-144090"
      unitRef="usd">11345</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000235226_LG_2_AdditionalIndexMember_5YR"
      id="ixv-3436">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg Municipal Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000235226_2_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-144091"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235226_2_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-144092"
      unitRef="usd">10168</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235226_2_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-144093"
      unitRef="usd">10463</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235226_2_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-144094"
      unitRef="usd">10681</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235226_2_AdditionalIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-144095"
      unitRef="usd">11183</oef:AccmVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000235226_ClassMember" id="ixv-3495">AVERAGE ANNUAL TOTAL RETURNS:

&#160;

1 Year

Life of Fund&#160;A


Class I

5.70%

3.88%


Bloomberg 3-15 Year Blend (2-17) Municipal Bond Index

5.72%


3.37%


Bloomberg Municipal Bond Index

4.70%


2.98%




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

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

&#160;


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





</oef:AvgAnnlRtrTableTextBlock>
    <oef:AvgAnnlRtrPct
      contextRef="C000235226_NoLoadClassMember_1YR"
      decimals="INF"
      id="ixv-144096"
      unitRef="pure">0.0570</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235226_NoLoadClassMember_2025-02-01_2026-01-31"
      decimals="INF"
      id="ixv-144097"
      unitRef="pure">0.0388</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235226_0_AdditionalIndexMember_1YR"
      decimals="INF"
      id="ixv-144098"
      unitRef="pure">0.0572</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235226_0_AdditionalIndexMember_LOC"
      decimals="INF"
      id="ixv-144099"
      unitRef="pure">0.0337</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235226_1_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-144100"
      unitRef="pure">0.0470</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235226_1_BBIndexMember_LOC"
      decimals="INF"
      id="ixv-144101"
      unitRef="pure">0.0298</oef:AvgAnnlRtrPct>
    <oef:PerfInceptionDate
      contextRef="C000235226_Perf_2022-04-13_ClassMember"
      id="ixv-3550">2022-04-13</oef:PerfInceptionDate>
    <oef:UpdPerfInfoLocationTextBlock contextRef="C000235226_ClassMember" id="ixv-3560">&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="C000235226_ClassMember" id="ixv-3572">&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="C000235226_ClassMember" id="ixv-3576">&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="C000235226_ClassMember" id="ixv-3582">&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 January 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;$&lt;/span&gt;26,103,588&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;271&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;88,312&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;16&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: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;/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="C000235226_InstantMember"
      decimals="0"
      id="ixv-144102"
      unitRef="usd">26103588</us-gaap:AssetsNet>
    <oef:HoldingsCount
      contextRef="C000235226_InstantMember"
      decimals="INF"
      id="ixv-144103"
      unitRef="holding">271</oef:HoldingsCount>
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      decimals="0"
      id="ixv-144104"
      unitRef="usd">88312</oef:AdvisoryFeesPaidAmt>
    <us-gaap:InvestmentCompanyPortfolioTurnover
      contextRef="C000235226_ClassMember"
      decimals="INF"
      id="ixv-144105"
      unitRef="pure">0.16</us-gaap:InvestmentCompanyPortfolioTurnover>
    <oef:HoldingsTableTextBlock contextRef="C000235226_ClassMember" id="ixv-3657">
&#160;
REVENUE SOURCES
 (% of Fund's net assets)


General Obligations

36.8

&#160;


Education

11.4

&#160;


Housing

11.1

&#160;


Health Care

9.5

&#160;


Electric Utilities

7.1

&#160;


Water &amp; Sewer

6.4

&#160;


Special Tax

6.2

&#160;


Transportation

5.0

&#160;


Others(Individually Less Than 5%)

3.1

&#160;


96.6

&#160;


&#160;




&#160;
AAA

12.4


AA

53.4


A

22.7


BBB

6.6


BB

1.3


Not Rated

0.2


Short-Term Investments and Net Other Assets (Liabilities)

3.4




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

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


&#160;

AA - 53.4&#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;

A - 22.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BBB - 6.6&#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;

BB - 1.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Not Rated - 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;

Short-Term Investments and Net Other Assets (Liabilities) - 3.4


&#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;
TOP STATES
(% of Fund's net assets)


Texas

13.8


Alabama

8.2


California

6.9


Georgia

5.4


Washington

5.3


&#160;

&#160;




&#160;
</oef:HoldingsTableTextBlock>
    <oef:PctOfNav
      contextRef="C000235226_RS_0_Member"
      decimals="INF"
      id="ixv-144106"
      unitRef="pure">0.368</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235226_RS_1_Member"
      decimals="INF"
      id="ixv-144107"
      unitRef="pure">0.114</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235226_RS_2_Member"
      decimals="INF"
      id="ixv-144108"
      unitRef="pure">0.111</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235226_RS_3_Member"
      decimals="INF"
      id="ixv-144109"
      unitRef="pure">0.095</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235226_RS_4_Member"
      decimals="INF"
      id="ixv-144110"
      unitRef="pure">0.071</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235226_RS_5_Member"
      decimals="INF"
      id="ixv-144111"
      unitRef="pure">0.064</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235226_RS_6_Member"
      decimals="INF"
      id="ixv-144112"
      unitRef="pure">0.062</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235226_RS_7_Member"
      decimals="INF"
      id="ixv-144113"
      unitRef="pure">0.050</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235226_RS_8_Member"
      decimals="INF"
      id="ixv-144114"
      unitRef="pure">0.031</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235226_QD_AAA_Member"
      decimals="INF"
      id="ixv-144115"
      unitRef="pure">0.124</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235226_QD_AA_Member"
      decimals="INF"
      id="ixv-144116"
      unitRef="pure">0.534</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235226_QD_A_Member"
      decimals="INF"
      id="ixv-144117"
      unitRef="pure">0.227</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235226_QD_BBB_Member"
      decimals="INF"
      id="ixv-144118"
      unitRef="pure">0.066</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235226_QD_BB_Member"
      decimals="INF"
      id="ixv-144119"
      unitRef="pure">0.013</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235226_QD_NotRated_Member"
      decimals="INF"
      id="ixv-144120"
      unitRef="pure">0.002</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235226_QD_ShortTermInvestmentsandNetOtherAssetsLiabilities_Member"
      decimals="INF"
      id="ixv-144121"
      unitRef="pure">0.034</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235226_TS_0_Member"
      decimals="INF"
      id="ixv-144122"
      unitRef="pure">0.138</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235226_TS_1_Member"
      decimals="INF"
      id="ixv-144123"
      unitRef="pure">0.082</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235226_TS_2_Member"
      decimals="INF"
      id="ixv-144124"
      unitRef="pure">0.069</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235226_TS_3_Member"
      decimals="INF"
      id="ixv-144125"
      unitRef="pure">0.054</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235226_TS_4_Member"
      decimals="INF"
      id="ixv-144126"
      unitRef="pure">0.053</oef:PctOfNav>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-3985">2026-01-31</dei:DocumentPeriodEndDate>
    <oef:FundName contextRef="C000235225_ClassMember" id="ixv-3997">Fidelity&#xae; Sustainable Intermediate Municipal Income Fund</oef:FundName>
    <oef:ClassName contextRef="C000235225_ClassMember" id="ixv-4000">Fidelity Advisor&#xae; Sustainable Intermediate Municipal Income Fund Class C</oef:ClassName>
    <dei:TradingSymbol contextRef="C000235225_ClassMember" id="ixv-4004">FASNX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000235225_ClassMember" id="ixv-4023">This annual shareholder report contains information about Fidelity&#xae; Sustainable Intermediate Municipal Income Fund for the period February 1, 2025 to January 31, 2026.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000235225_ClassMember" id="ixv-4025">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000235225_ClassMember" id="ixv-4030">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="C000235225_ClassMember" id="ixv-4032">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000235225_ClassMember" id="ixv-4035">1-877-208-0098</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000235225_ClassMember" id="ixv-4038">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000235225_ClassMember" id="ixv-4045">&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 $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:51%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Class C&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:21%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$ &lt;/span&gt;140&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;1.37&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="C000235225_ClassMember"
      decimals="0"
      id="ixv-144127"
      unitRef="usd">140</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000235225_ClassMember"
      decimals="INF"
      id="ixv-144128"
      unitRef="pure">0.0137</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000235225_ClassMember" id="ixv-4087">&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. tax-exempt municipal bonds notched a strong gain for the 12 months ending January 31, 2026, bolstered by a second-half rally driven by three policy interest-rate cuts by the Federal Reserve since September, moderating muni supply and firming investor demand.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Against this backdrop, the fund's "carry" advantage, meaning its proportionately larger stake in higher-yielding bonds, contributed to performance versus the Bloomberg 3-15 Year Blend (2-17) 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;An overweight in the housing and utilities sectors further boosted 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 "positive convexity," meaning its exposure to non-callable and longer-call bonds, as well as the portfolio managers' active management of call risk, was also helpful.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;In contrast, the fund's overweight in health care bonds detracted from performance versus the 3-15 year index.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Underweights in certain higher-quality securities, including those in the state general obligation and the water &amp;amp; sewer sectors, also hurt.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Pricing factors crimped the relative result as well. Fund holdings are priced by a third-party pricing service and validated daily by Fidelity Management &amp;amp; Research's fair-value processes. Securities within the index, however, are priced by the index provider. These two approaches employ somewhat different methodologies in estimating the prices of municipal securities, most of which trade infrequently.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;During the year, the portfolio management team reduced the fund's exposure to the health care and higher education sectors and pared back exposure to lower-quality securities.&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 (ESG) 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;span style="line-height:13px;"&gt;&#160;&lt;/span&gt;&lt;div style="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;/div&gt;</oef:FactorsAffectingPerfTextBlock>
    <oef:LineGraphTableTextBlock contextRef="C000235225_ClassMember" id="ixv-4124">How did the Fund perform over the life of Fund?

 &#160;&#160;
CUMULATIVE PERFORMANCE
April 13, 2022 through January 31, 2026. 
Initial investment of $10,000.
Class C


$10,000

$10,262


$10,508


$10,634


$11,118



Bloomberg 3-15 Year Blend (2-17) Municipal Bond Index


$10,000

$10,276


$10,537


$10,731


$11,345



Bloomberg Municipal Bond Index


$10,000

$10,168


$10,463


$10,681


$11,183



&#160;

2022

2023

2024

2025

2026









&#160;
</oef:LineGraphTableTextBlock>
    <oef:LineGraphAndTableMeasureName contextRef="C000235225_LG_ClassMember_5YR" id="ixv-4143">&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="C000235225_ClassMember_AsOf_2022"
      decimals="0"
      id="ixv-144129"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235225_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-144130"
      unitRef="usd">10262</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235225_ClassMember_AsOf_2024"
      decimals="0"
      id="ixv-144131"
      unitRef="usd">10508</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235225_ClassMember_AsOf_2025"
      decimals="0"
      id="ixv-144132"
      unitRef="usd">10634</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235225_ClassMember_AsOf_2026"
      decimals="0"
      id="ixv-144133"
      unitRef="usd">11118</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000235225_LG_1_AdditionalIndexMember_5YR"
      id="ixv-4168">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg 3-15 Year Blend (2-17) Municipal Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000235225_1_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-144134"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235225_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-144135"
      unitRef="usd">10276</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235225_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-144136"
      unitRef="usd">10537</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235225_1_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-144137"
      unitRef="usd">10731</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235225_1_AdditionalIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-144138"
      unitRef="usd">11345</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000235225_LG_2_AdditionalIndexMember_5YR"
      id="ixv-4193">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg Municipal Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000235225_2_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-144139"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235225_2_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-144140"
      unitRef="usd">10168</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235225_2_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-144141"
      unitRef="usd">10463</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235225_2_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-144142"
      unitRef="usd">10681</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235225_2_AdditionalIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-144143"
      unitRef="usd">11183</oef:AccmVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000235225_ClassMember" id="ixv-4252">AVERAGE ANNUAL TOTAL RETURNS:

&#160;

1 Year

Life of Fund&#160;A


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

3.55%

2.82%


Class C

4.55%

2.82%


Bloomberg 3-15 Year Blend (2-17) Municipal Bond Index

5.72%


3.37%


Bloomberg Municipal Bond Index

4.70%


2.98%




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

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

&#160;


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





</oef:AvgAnnlRtrTableTextBlock>
    <oef:AvgAnnlRtrPct
      contextRef="C000235225_ClassMember_1YR"
      decimals="INF"
      id="ixv-144144"
      unitRef="pure">0.0355</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235225_ClassMember_2025-02-01_2026-01-31"
      decimals="INF"
      id="ixv-144145"
      unitRef="pure">0.0282</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235225_NoLoadClassMember_1YR"
      decimals="INF"
      id="ixv-144146"
      unitRef="pure">0.0455</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235225_NoLoadClassMember_2025-02-01_2026-01-31"
      decimals="INF"
      id="ixv-144147"
      unitRef="pure">0.0282</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235225_0_AdditionalIndexMember_1YR"
      decimals="INF"
      id="ixv-144148"
      unitRef="pure">0.0572</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235225_0_AdditionalIndexMember_LOC"
      decimals="INF"
      id="ixv-144149"
      unitRef="pure">0.0337</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235225_1_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-144150"
      unitRef="pure">0.0470</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235225_1_BBIndexMember_LOC"
      decimals="INF"
      id="ixv-144151"
      unitRef="pure">0.0298</oef:AvgAnnlRtrPct>
    <oef:PerfInceptionDate
      contextRef="C000235225_Perf_2022-04-13_ClassMember"
      id="ixv-4319">2022-04-13</oef:PerfInceptionDate>
    <oef:UpdPerfInfoLocationTextBlock contextRef="C000235225_ClassMember" id="ixv-4329">&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="C000235225_ClassMember" id="ixv-4341">&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="C000235225_ClassMember" id="ixv-4345">&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="C000235225_ClassMember" id="ixv-4351">&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 January 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;$&lt;/span&gt;26,103,588&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;271&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;88,312&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;16&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: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;/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="C000235225_InstantMember"
      decimals="0"
      id="ixv-144152"
      unitRef="usd">26103588</us-gaap:AssetsNet>
    <oef:HoldingsCount
      contextRef="C000235225_InstantMember"
      decimals="INF"
      id="ixv-144153"
      unitRef="holding">271</oef:HoldingsCount>
    <oef:AdvisoryFeesPaidAmt
      contextRef="C000235225_ClassMember"
      decimals="0"
      id="ixv-144154"
      unitRef="usd">88312</oef:AdvisoryFeesPaidAmt>
    <us-gaap:InvestmentCompanyPortfolioTurnover
      contextRef="C000235225_ClassMember"
      decimals="INF"
      id="ixv-144155"
      unitRef="pure">0.16</us-gaap:InvestmentCompanyPortfolioTurnover>
    <oef:HoldingsTableTextBlock contextRef="C000235225_ClassMember" id="ixv-4426">
&#160;
REVENUE SOURCES
 (% of Fund's net assets)


General Obligations

36.8

&#160;


Education

11.4

&#160;


Housing

11.1

&#160;


Health Care

9.5

&#160;


Electric Utilities

7.1

&#160;


Water &amp; Sewer

6.4

&#160;


Special Tax

6.2

&#160;


Transportation

5.0

&#160;


Others(Individually Less Than 5%)

3.1

&#160;


96.6

&#160;


&#160;




&#160;
AAA

12.4


AA

53.4


A

22.7


BBB

6.6


BB

1.3


Not Rated

0.2


Short-Term Investments and Net Other Assets (Liabilities)

3.4




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

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


&#160;

AA - 53.4&#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;

A - 22.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BBB - 6.6&#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;

BB - 1.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Not Rated - 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;

Short-Term Investments and Net Other Assets (Liabilities) - 3.4


&#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;
TOP STATES
(% of Fund's net assets)


Texas

13.8


Alabama

8.2


California

6.9


Georgia

5.4


Washington

5.3


&#160;

&#160;




&#160;
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      unitRef="pure">0.534</oef:PctOfNav>
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      unitRef="pure">0.227</oef:PctOfNav>
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      id="ixv-144170"
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      contextRef="C000235225_TS_0_Member"
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      id="ixv-144172"
      unitRef="pure">0.138</oef:PctOfNav>
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      id="ixv-144173"
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      unitRef="pure">0.069</oef:PctOfNav>
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    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-4754">2026-01-31</dei:DocumentPeriodEndDate>
    <oef:FundName contextRef="C000235228_ClassMember" id="ixv-4766">Fidelity&#xae; Sustainable Intermediate Municipal Income Fund</oef:FundName>
    <oef:ClassName contextRef="C000235228_ClassMember" id="ixv-4769">Fidelity Advisor&#xae; Sustainable Intermediate Municipal Income Fund Class A</oef:ClassName>
    <dei:TradingSymbol contextRef="C000235228_ClassMember" id="ixv-4773">FASJX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000235228_ClassMember" id="ixv-4792">This annual shareholder report contains information about Fidelity&#xae; Sustainable Intermediate Municipal Income Fund for the period February 1, 2025 to January 31, 2026.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000235228_ClassMember" id="ixv-4794">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000235228_ClassMember" id="ixv-4799">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="C000235228_ClassMember" id="ixv-4801">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000235228_ClassMember" id="ixv-4804">1-877-208-0098</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000235228_ClassMember" id="ixv-4807">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000235228_ClassMember" id="ixv-4814">&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 $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:51%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Class A&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:21%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$ &lt;/span&gt;64&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;0.62&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:ExpensesTextBlock>
    <oef:ExpensesPaidAmt
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      unitRef="usd">64</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000235228_ClassMember"
      decimals="INF"
      id="ixv-144178"
      unitRef="pure">0.0062</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000235228_ClassMember" id="ixv-4856">&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. tax-exempt municipal bonds notched a strong gain for the 12 months ending January 31, 2026, bolstered by a second-half rally driven by three policy interest-rate cuts by the Federal Reserve since September, moderating muni supply and firming investor demand.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Against this backdrop, the fund's "carry" advantage, meaning its proportionately larger stake in higher-yielding bonds, contributed to performance versus the Bloomberg 3-15 Year Blend (2-17) 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;An overweight in the housing and utilities sectors further boosted 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 "positive convexity," meaning its exposure to non-callable and longer-call bonds, as well as the portfolio managers' active management of call risk, was also helpful.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;In contrast, the fund's overweight in health care bonds detracted from performance versus the 3-15 year index.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Underweights in certain higher-quality securities, including those in the state general obligation and the water &amp;amp; sewer sectors, also hurt.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Pricing factors crimped the relative result as well. Fund holdings are priced by a third-party pricing service and validated daily by Fidelity Management &amp;amp; Research's fair-value processes. Securities within the index, however, are priced by the index provider. These two approaches employ somewhat different methodologies in estimating the prices of municipal securities, most of which trade infrequently.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;During the year, the portfolio management team reduced the fund's exposure to the health care and higher education sectors and pared back exposure to lower-quality securities.&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 (ESG) 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;span style="line-height:13px;"&gt;&#160;&lt;/span&gt;&lt;div style="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;/div&gt;</oef:FactorsAffectingPerfTextBlock>
    <oef:LineGraphTableTextBlock contextRef="C000235228_ClassMember" id="ixv-4893">How did the Fund perform over the life of Fund?

 &#160;&#160;
CUMULATIVE PERFORMANCE
April 13, 2022 through January 31, 2026. 
Initial investment of $10,000&#160;and the current sales charge was paid.
Class A


$9,600

$9,911


$10,218


$10,425


$10,981



Bloomberg 3-15 Year Blend (2-17) Municipal Bond Index


$10,000

$10,276


$10,537


$10,731


$11,345



Bloomberg Municipal Bond Index


$10,000

$10,168


$10,463


$10,681


$11,183



&#160;

2022

2023

2024

2025

2026









&#160;
</oef:LineGraphTableTextBlock>
    <oef:LineGraphAndTableMeasureName contextRef="C000235228_LG_ClassMember_5YR" id="ixv-4914">&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="C000235228_ClassMember_AsOf_2022"
      decimals="0"
      id="ixv-144179"
      unitRef="usd">9600</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235228_ClassMember_AsOf_2023"
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      id="ixv-144180"
      unitRef="usd">9911</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235228_ClassMember_AsOf_2024"
      decimals="0"
      id="ixv-144181"
      unitRef="usd">10218</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235228_ClassMember_AsOf_2025"
      decimals="0"
      id="ixv-144182"
      unitRef="usd">10425</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235228_ClassMember_AsOf_2026"
      decimals="0"
      id="ixv-144183"
      unitRef="usd">10981</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000235228_LG_1_AdditionalIndexMember_5YR"
      id="ixv-4939">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg 3-15 Year Blend (2-17) Municipal Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000235228_1_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-144184"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235228_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-144185"
      unitRef="usd">10276</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235228_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-144186"
      unitRef="usd">10537</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235228_1_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-144187"
      unitRef="usd">10731</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235228_1_AdditionalIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-144188"
      unitRef="usd">11345</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000235228_LG_2_AdditionalIndexMember_5YR"
      id="ixv-4964">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg Municipal Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000235228_2_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-144189"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235228_2_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-144190"
      unitRef="usd">10168</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235228_2_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-144191"
      unitRef="usd">10463</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235228_2_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-144192"
      unitRef="usd">10681</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235228_2_AdditionalIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-144193"
      unitRef="usd">11183</oef:AccmVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000235228_ClassMember" id="ixv-5023">AVERAGE ANNUAL TOTAL RETURNS:

&#160;

1 Year

Life of Fund&#160;A


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

1.12%

2.49%


Class A (without 4.00% sales charge)

5.33%

3.59%


Bloomberg 3-15 Year Blend (2-17) Municipal Bond Index

5.72%


3.37%


Bloomberg Municipal Bond Index

4.70%


2.98%




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

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

&#160;


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





</oef:AvgAnnlRtrTableTextBlock>
    <oef:AvgAnnlRtrPct
      contextRef="C000235228_ClassMember_1YR"
      decimals="INF"
      id="ixv-144194"
      unitRef="pure">0.0112</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235228_ClassMember_2025-02-01_2026-01-31"
      decimals="INF"
      id="ixv-144195"
      unitRef="pure">0.0249</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235228_NoLoadClassMember_1YR"
      decimals="INF"
      id="ixv-144196"
      unitRef="pure">0.0533</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235228_NoLoadClassMember_2025-02-01_2026-01-31"
      decimals="INF"
      id="ixv-144197"
      unitRef="pure">0.0359</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235228_0_AdditionalIndexMember_1YR"
      decimals="INF"
      id="ixv-144198"
      unitRef="pure">0.0572</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235228_0_AdditionalIndexMember_LOC"
      decimals="INF"
      id="ixv-144199"
      unitRef="pure">0.0337</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235228_1_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-144200"
      unitRef="pure">0.0470</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235228_1_BBIndexMember_LOC"
      decimals="INF"
      id="ixv-144201"
      unitRef="pure">0.0298</oef:AvgAnnlRtrPct>
    <oef:PerfInceptionDate
      contextRef="C000235228_Perf_2022-04-13_ClassMember"
      id="ixv-5089">2022-04-13</oef:PerfInceptionDate>
    <oef:UpdPerfInfoLocationTextBlock contextRef="C000235228_ClassMember" id="ixv-5099">&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="C000235228_ClassMember" id="ixv-5111">&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="C000235228_ClassMember" id="ixv-5115">&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="C000235228_ClassMember" id="ixv-5121">&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 January 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;$&lt;/span&gt;26,103,588&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;271&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;88,312&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;16&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: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;/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="C000235228_InstantMember"
      decimals="0"
      id="ixv-144202"
      unitRef="usd">26103588</us-gaap:AssetsNet>
    <oef:HoldingsCount
      contextRef="C000235228_InstantMember"
      decimals="INF"
      id="ixv-144203"
      unitRef="holding">271</oef:HoldingsCount>
    <oef:AdvisoryFeesPaidAmt
      contextRef="C000235228_ClassMember"
      decimals="0"
      id="ixv-144204"
      unitRef="usd">88312</oef:AdvisoryFeesPaidAmt>
    <us-gaap:InvestmentCompanyPortfolioTurnover
      contextRef="C000235228_ClassMember"
      decimals="INF"
      id="ixv-144205"
      unitRef="pure">0.16</us-gaap:InvestmentCompanyPortfolioTurnover>
    <oef:HoldingsTableTextBlock contextRef="C000235228_ClassMember" id="ixv-5196">
&#160;
REVENUE SOURCES
 (% of Fund's net assets)


General Obligations

36.8

&#160;


Education

11.4

&#160;


Housing

11.1

&#160;


Health Care

9.5

&#160;


Electric Utilities

7.1

&#160;


Water &amp; Sewer

6.4

&#160;


Special Tax

6.2

&#160;


Transportation

5.0

&#160;


Others(Individually Less Than 5%)

3.1

&#160;


96.6

&#160;


&#160;




&#160;
AAA

12.4


AA

53.4


A

22.7


BBB

6.6


BB

1.3


Not Rated

0.2


Short-Term Investments and Net Other Assets (Liabilities)

3.4




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

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


&#160;

AA - 53.4&#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;

A - 22.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BBB - 6.6&#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;

BB - 1.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Not Rated - 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;

Short-Term Investments and Net Other Assets (Liabilities) - 3.4


&#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;
TOP STATES
(% of Fund's net assets)


Texas

13.8


Alabama

8.2


California

6.9


Georgia

5.4


Washington

5.3


&#160;

&#160;




&#160;
</oef:HoldingsTableTextBlock>
    <oef:PctOfNav
      contextRef="C000235228_RS_0_Member"
      decimals="INF"
      id="ixv-144206"
      unitRef="pure">0.368</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235228_RS_1_Member"
      decimals="INF"
      id="ixv-144207"
      unitRef="pure">0.114</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235228_RS_2_Member"
      decimals="INF"
      id="ixv-144208"
      unitRef="pure">0.111</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235228_RS_3_Member"
      decimals="INF"
      id="ixv-144209"
      unitRef="pure">0.095</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235228_RS_4_Member"
      decimals="INF"
      id="ixv-144210"
      unitRef="pure">0.071</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235228_RS_5_Member"
      decimals="INF"
      id="ixv-144211"
      unitRef="pure">0.064</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235228_RS_6_Member"
      decimals="INF"
      id="ixv-144212"
      unitRef="pure">0.062</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235228_RS_7_Member"
      decimals="INF"
      id="ixv-144213"
      unitRef="pure">0.050</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235228_RS_8_Member"
      decimals="INF"
      id="ixv-144214"
      unitRef="pure">0.031</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235228_QD_AAA_Member"
      decimals="INF"
      id="ixv-144215"
      unitRef="pure">0.124</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235228_QD_AA_Member"
      decimals="INF"
      id="ixv-144216"
      unitRef="pure">0.534</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235228_QD_A_Member"
      decimals="INF"
      id="ixv-144217"
      unitRef="pure">0.227</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235228_QD_BBB_Member"
      decimals="INF"
      id="ixv-144218"
      unitRef="pure">0.066</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235228_QD_BB_Member"
      decimals="INF"
      id="ixv-144219"
      unitRef="pure">0.013</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235228_QD_NotRated_Member"
      decimals="INF"
      id="ixv-144220"
      unitRef="pure">0.002</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235228_QD_ShortTermInvestmentsandNetOtherAssetsLiabilities_Member"
      decimals="INF"
      id="ixv-144221"
      unitRef="pure">0.034</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235228_TS_0_Member"
      decimals="INF"
      id="ixv-144222"
      unitRef="pure">0.138</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235228_TS_1_Member"
      decimals="INF"
      id="ixv-144223"
      unitRef="pure">0.082</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235228_TS_2_Member"
      decimals="INF"
      id="ixv-144224"
      unitRef="pure">0.069</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235228_TS_3_Member"
      decimals="INF"
      id="ixv-144225"
      unitRef="pure">0.054</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235228_TS_4_Member"
      decimals="INF"
      id="ixv-144226"
      unitRef="pure">0.053</oef:PctOfNav>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-5524">2026-01-31</dei:DocumentPeriodEndDate>
    <oef:MaterialFundChngNoticeTextBlock contextRef="C000131781_ClassMember" id="ixv-5528">This report describes changes to the Fund that occurred during the reporting period.</oef:MaterialFundChngNoticeTextBlock>
    <oef:FundName contextRef="C000131781_ClassMember" id="ixv-5539">Fidelity&#xae; Series Large Cap Value Index Fund</oef:FundName>
    <oef:ClassName contextRef="C000131781_ClassMember" id="ixv-5542">Fidelity&#xae; Series Large Cap Value Index Fund</oef:ClassName>
    <dei:TradingSymbol contextRef="C000131781_ClassMember" id="ixv-5546">FIOOX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000131781_ClassMember" id="ixv-5565">This annual shareholder report contains information about Fidelity&#xae; Series Large Cap Value Index Fund for the period February 1, 2025 to January 31, 2026.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000131781_ClassMember" id="ixv-5567">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000131781_ClassMember" id="ixv-5572">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="C000131781_ClassMember" id="ixv-5574">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000131781_ClassMember" id="ixv-5577">1-800-544-8544</oef:AddlInfoPhoneNumber>
    <oef:ExpensesTextBlock contextRef="C000131781_ClassMember" id="ixv-5584">&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 $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:51%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity&#xae; Series Large Cap Value Index Fund&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:21%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$ &lt;/span&gt;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="C000131781_ClassMember"
      decimals="0"
      id="ixv-144227"
      unitRef="usd">0</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000131781_ClassMember"
      decimals="INF"
      id="ixv-144228"
      unitRef="pure">0.0000</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000131781_ClassMember" id="ixv-5636">&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. stocks achieved a strong gain for the 12 months ending January 31, 2026, extending a historically fast rebound that began in early April, bolstered by strong corporate fundamentals, a resilient economy and, beginning in September, the Federal Reserve's first interest-rate reductions since December 2024.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity 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, information technology gained roughly 33% and contributed most to the fund's performance for the fiscal year, driven by the semiconductors &amp;amp; semiconductor equipment industry (+81%). Industrials, which gained about 24%, also helped, benefiting from the capital goods industry (+30%), as did communication services, which advanced roughly 41%, lifted by the media &amp;amp; entertainment industry (+56%). The financials sector rose 9%, while energy gained roughly 22% and consumer staples advanced 11%. Other contributors included the materials (+18%), utilities (+16%), consumer discretionary (+7%), health care (+4%) and real estate (+4%) sectors.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Turning to individual stocks, the biggest contributor was Alphabet (+90%), from the media &amp;amp; entertainment industry. Micron Technology (+356%), from the semiconductors &amp;amp; semiconductor equipment industry, contributed. In pharmaceuticals, biotechnology &amp;amp; life sciences, Johnson &amp;amp; Johnson (+54%) lifted the fund. In energy, Exxon Mobil gained approximately 37% and lifted the fund. Lastly, JPMorgan Chase (+17%), a stock in the banks group, also lifted the fund.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Conversely, the biggest detractor was UnitedHealth (-46%), from the health care equipment &amp;amp; services industry. Accenture (-30%), Salesforce (-37%) and Strategy (-55%), within the software &amp;amp; services category, detracted. Lastly, Fiserv (-71%), from the financial services group, also hurt 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="C000131781_ClassMember" id="ixv-5654">How did the Fund perform over the past 10 years?

 &#160;&#160;
CUMULATIVE PERFORMANCE
January 31, 2016 through January 31, 2026. 
Initial investment of $10,000.
Fidelity&#xae; Series Large Cap Value Index Fund


$10,000

$12,444


$14,578


$13,888


$15,963


$16,624


$20,517


$20,435


$21,686


$25,935


$30,026



Russell 1000&#xae; Value Index


$10,000

$12,462


$14,608


$13,906


$15,974


$16,628


$20,515


$20,428


$21,670


$25,904


$30,006



Russell 1000&#xae; Index


$10,000

$12,081


$15,202


$14,872


$18,053


$21,635


$26,030


$23,805


$28,621


$36,265


$41,818



&#160;

2016

2017

2018

2019

2020

2021

2022

2023

2024

2025

2026









&#160;
</oef:LineGraphTableTextBlock>
    <oef:LineGraphAndTableMeasureName contextRef="C000131781_LG_ClassMember_11YR" id="ixv-5673">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity&#xae; Series Large Cap Value Index Fund&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000131781_ClassMember_AsOf_2016"
      decimals="0"
      id="ixv-144229"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000131781_ClassMember_AsOf_2017"
      decimals="0"
      id="ixv-144230"
      unitRef="usd">12444</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000131781_ClassMember_AsOf_2018"
      decimals="0"
      id="ixv-144231"
      unitRef="usd">14578</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000131781_ClassMember_AsOf_2019"
      decimals="0"
      id="ixv-144232"
      unitRef="usd">13888</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000131781_ClassMember_AsOf_2020"
      decimals="0"
      id="ixv-144233"
      unitRef="usd">15963</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000131781_ClassMember_AsOf_2021"
      decimals="0"
      id="ixv-144234"
      unitRef="usd">16624</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000131781_ClassMember_AsOf_2022"
      decimals="0"
      id="ixv-144235"
      unitRef="usd">20517</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000131781_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-144236"
      unitRef="usd">20435</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000131781_ClassMember_AsOf_2024"
      decimals="0"
      id="ixv-144237"
      unitRef="usd">21686</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000131781_ClassMember_AsOf_2025"
      decimals="0"
      id="ixv-144238"
      unitRef="usd">25935</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000131781_ClassMember_AsOf_2026"
      decimals="0"
      id="ixv-144239"
      unitRef="usd">30026</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000131781_LG_1_AdditionalIndexMember_11YR"
      id="ixv-5722">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Russell 1000&#xae; Value Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000131781_1_AdditionalIndexMember_AsOf_2016"
      decimals="0"
      id="ixv-144240"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000131781_1_AdditionalIndexMember_AsOf_2017"
      decimals="0"
      id="ixv-144241"
      unitRef="usd">12462</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000131781_1_AdditionalIndexMember_AsOf_2018"
      decimals="0"
      id="ixv-144242"
      unitRef="usd">14608</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000131781_1_AdditionalIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-144243"
      unitRef="usd">13906</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000131781_1_AdditionalIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-144244"
      unitRef="usd">15974</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000131781_1_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-144245"
      unitRef="usd">16628</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000131781_1_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-144246"
      unitRef="usd">20515</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000131781_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-144247"
      unitRef="usd">20428</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000131781_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-144248"
      unitRef="usd">21670</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000131781_1_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-144249"
      unitRef="usd">25904</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000131781_1_AdditionalIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-144250"
      unitRef="usd">30006</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000131781_LG_2_AdditionalIndexMember_11YR"
      id="ixv-5771">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Russell 1000&#xae; Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000131781_2_AdditionalIndexMember_AsOf_2016"
      decimals="0"
      id="ixv-144251"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000131781_2_AdditionalIndexMember_AsOf_2017"
      decimals="0"
      id="ixv-144252"
      unitRef="usd">12081</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000131781_2_AdditionalIndexMember_AsOf_2018"
      decimals="0"
      id="ixv-144253"
      unitRef="usd">15202</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000131781_2_AdditionalIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-144254"
      unitRef="usd">14872</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000131781_2_AdditionalIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-144255"
      unitRef="usd">18053</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000131781_2_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-144256"
      unitRef="usd">21635</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000131781_2_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-144257"
      unitRef="usd">26030</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000131781_2_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-144258"
      unitRef="usd">23805</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000131781_2_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-144259"
      unitRef="usd">28621</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000131781_2_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-144260"
      unitRef="usd">36265</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000131781_2_AdditionalIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-144261"
      unitRef="usd">41818</oef:AccmVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000131781_ClassMember" id="ixv-5872">AVERAGE ANNUAL TOTAL RETURNS:

&#160;

1 Year

5 Year

10 Year


Fidelity&#xae; Series Large Cap Value Index Fund

15.78%

12.55%

11.62%


Russell 1000&#xae; Value Index

15.83%


12.53%


11.61%


Russell 1000&#xae; Index

15.31%


14.09%


15.38%




&#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
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      decimals="INF"
      id="ixv-144262"
      unitRef="pure">0.1578</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000131781_NoLoadClassMember_5YR"
      decimals="INF"
      id="ixv-144263"
      unitRef="pure">0.1255</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000131781_NoLoadClassMember_10YR"
      decimals="INF"
      id="ixv-144264"
      unitRef="pure">0.1162</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000131781_0_AdditionalIndexMember_1YR"
      decimals="INF"
      id="ixv-144265"
      unitRef="pure">0.1583</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000131781_0_AdditionalIndexMember_5YR"
      decimals="INF"
      id="ixv-144266"
      unitRef="pure">0.1253</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000131781_0_AdditionalIndexMember_10YR"
      decimals="INF"
      id="ixv-144267"
      unitRef="pure">0.1161</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000131781_1_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-144268"
      unitRef="pure">0.1531</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000131781_1_BBIndexMember_5YR"
      decimals="INF"
      id="ixv-144269"
      unitRef="pure">0.1409</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000131781_1_BBIndexMember_10YR"
      decimals="INF"
      id="ixv-144270"
      unitRef="pure">0.1538</oef:AvgAnnlRtrPct>
    <oef:UpdPerfInfoLocationTextBlock contextRef="C000131781_ClassMember" id="ixv-5942">&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="C000131781_ClassMember" id="ixv-5954">&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="C000131781_ClassMember" id="ixv-5958">&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="C000131781_ClassMember" id="ixv-5964">&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 January 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;$&lt;/span&gt;10,868,269,310&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;874&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&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;17&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: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;/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="C000131781_InstantMember"
      decimals="0"
      id="ixv-144271"
      unitRef="usd">10868269310</us-gaap:AssetsNet>
    <oef:HoldingsCount
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      decimals="INF"
      id="ixv-144272"
      unitRef="holding">874</oef:HoldingsCount>
    <oef:AdvisoryFeesPaidAmt
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      unitRef="usd">0</oef:AdvisoryFeesPaidAmt>
    <us-gaap:InvestmentCompanyPortfolioTurnover
      contextRef="C000131781_ClassMember"
      decimals="INF"
      id="ixv-144274"
      unitRef="pure">0.17</us-gaap:InvestmentCompanyPortfolioTurnover>
    <oef:HoldingsTableTextBlock contextRef="C000131781_ClassMember" id="ixv-6039">
&#160;
&#160;
&#160;
MARKET SECTORS
(% of Fund's net assets)

&#160;

&#160;


Financials

20.9

&#160;


Industrials

13.6

&#160;


Information Technology

11.8

&#160;


Health Care

11.8

&#160;


Communication Services

8.4

&#160;


Consumer Staples

7.4

&#160;


Consumer Discretionary

7.3

&#160;


Energy

6.3

&#160;


Materials

4.3

&#160;


Utilities

4.2

&#160;


Real Estate

3.9

&#160;


&#160;




Common Stocks

99.9


Short-Term Investments and Net Other Assets (Liabilities)

0.1




ASSET ALLOCATION (% of Fund's net assets)


&#160;



&#160;

Common Stocks - 99.9&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Short-Term Investments and Net Other Assets (Liabilities) - 0.1


&#160;






United States

99.4


Canada

0.2


Australia

0.2


United Kingdom

0.1


Mexico

0.1


Bermuda

0.0


Puerto Rico

0.0


Brazil

0.0


Guatemala

0.0




GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

United States - 99.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Canada - 0.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Australia - 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;

United Kingdom - 0.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Mexico - 0.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Bermuda - 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;

Puerto Rico - 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;

Brazil - 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;

Guatemala - 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;
</oef:HoldingsTableTextBlock>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-144275"
      unitRef="pure">0.209</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-144276"
      unitRef="pure">0.136</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000131781_MS_InformationTechnologySectorMember"
      decimals="INF"
      id="ixv-144277"
      unitRef="pure">0.118</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-144278"
      unitRef="pure">0.118</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000131781_MS_CommunicationsSectorMember"
      decimals="INF"
      id="ixv-144279"
      unitRef="pure">0.084</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000131781_MS_ConsumerStaplesSectorMember"
      decimals="INF"
      id="ixv-144280"
      unitRef="pure">0.074</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000131781_MS_ConsumerDiscretionarySectorMember"
      decimals="INF"
      id="ixv-144281"
      unitRef="pure">0.073</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000131781_MS_EnergySectorMember"
      decimals="INF"
      id="ixv-144282"
      unitRef="pure">0.063</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000131781_MS_MaterialsSectorMember"
      decimals="INF"
      id="ixv-144283"
      unitRef="pure">0.043</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000131781_MS_UtilitiesSectorMember"
      decimals="INF"
      id="ixv-144284"
      unitRef="pure">0.042</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000131781_MS_RealEstateSectorMember"
      decimals="INF"
      id="ixv-144285"
      unitRef="pure">0.039</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000131781_AA_CommonStocks_Member"
      decimals="INF"
      id="ixv-144286"
      unitRef="pure">0.999</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-144287"
      unitRef="pure">0.001</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000131781_GD_US_Member"
      decimals="INF"
      id="ixv-144288"
      unitRef="pure">0.994</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000131781_GD_CA_Member"
      decimals="INF"
      id="ixv-144289"
      unitRef="pure">0.002</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000131781_GD_AU_Member"
      decimals="INF"
      id="ixv-144290"
      unitRef="pure">0.002</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000131781_GD_GB_Member"
      decimals="INF"
      id="ixv-144291"
      unitRef="pure">0.001</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-144292"
      unitRef="pure">0.001</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-144293"
      unitRef="pure">0.000</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-144294"
      unitRef="pure">0.000</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000131781_GD_BR_Member"
      decimals="INF"
      id="ixv-144295"
      unitRef="pure">0.000</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000131781_GD_GT_Member"
      decimals="INF"
      id="ixv-144296"
      unitRef="pure">0.000</oef:PctOfNav>
    <oef:LargestHoldingsTableTextBlock contextRef="C000131781_ClassMember" id="ixv-6365">TOP HOLDINGS(% of Fund's net assets)

&#160;

&#160;


Berkshire Hathaway Inc Class B

2.8


&#160;


JPMorgan Chase &amp; Co

2.8


&#160;


Alphabet Inc Class A

2.3


&#160;


Amazon.com Inc

2.1


&#160;


Exxon Mobil Corp

2.0


&#160;


Alphabet Inc Class C

1.8


&#160;


Johnson &amp; Johnson

1.8


&#160;


Micron Technology Inc

1.6


&#160;


Walmart Inc

1.5


&#160;


Procter &amp; Gamble Co/The

1.2


&#160;


&#160;

19.9

&#160;



</oef:LargestHoldingsTableTextBlock>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-144297"
      unitRef="pure">0.028</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000131781_TH_1_Member"
      decimals="INF"
      id="ixv-144298"
      unitRef="pure">0.028</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000131781_TH_2_Member"
      decimals="INF"
      id="ixv-144299"
      unitRef="pure">0.023</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000131781_TH_3_Member"
      decimals="INF"
      id="ixv-144300"
      unitRef="pure">0.021</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000131781_TH_4_Member"
      decimals="INF"
      id="ixv-144301"
      unitRef="pure">0.020</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000131781_TH_5_Member"
      decimals="INF"
      id="ixv-144302"
      unitRef="pure">0.018</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000131781_TH_6_Member"
      decimals="INF"
      id="ixv-144303"
      unitRef="pure">0.018</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000131781_TH_7_Member"
      decimals="INF"
      id="ixv-144304"
      unitRef="pure">0.016</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000131781_TH_8_Member"
      decimals="INF"
      id="ixv-144305"
      unitRef="pure">0.015</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000131781_TH_9_Member"
      decimals="INF"
      id="ixv-144306"
      unitRef="pure">0.012</oef:PctOfNav>
    <oef:MaterialFundChngTextBlock contextRef="C000131781_ClassMember" id="ixv-6490">
&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 February 1, 2025. For more complete information, you may review the Fund's next prospectus, which we expect to be available by&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;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;April 1, 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;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 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;&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="C000131781_ClassMember" id="ixv-6496">&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 February 1, 2025. For more complete information, you may review the Fund's next prospectus, which we expect to be available by&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;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;April 1, 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="C000131781_ClassMember" id="ixv-6500">&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="C000131781_ClassMember" id="ixv-6503">&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:MaterialFundChngStrategiesTextBlock contextRef="C000131781_ClassMember" id="ixv-6515">&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 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:MaterialFundChngStrategiesTextBlock>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-6573">2026-01-31</dei:DocumentPeriodEndDate>
    <oef:FundName contextRef="C000200825_ClassMember" id="ixv-6585">Fidelity&#xae; SAI Tax-Free Bond Fund</oef:FundName>
    <oef:ClassName contextRef="C000200825_ClassMember" id="ixv-6588">Fidelity&#xae; SAI Tax-Free Bond Fund</oef:ClassName>
    <dei:TradingSymbol contextRef="C000200825_ClassMember" id="ixv-6592">FSAJX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000200825_ClassMember" id="ixv-6611">This annual shareholder report contains information about Fidelity&#xae; SAI Tax-Free Bond Fund for the period February 1, 2025 to January 31, 2026.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000200825_ClassMember" id="ixv-6613">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000200825_ClassMember" id="ixv-6618">You can find additional information about the Fund at fundresearch.fidelity.com/prospectus/sec. You can also request this information by contacting us at 1-800-544-3455 or by sending an e-mail to fidfunddocuments@fidelity.com.</oef:AddlInfoTextBlock>
    <oef:AddlInfoWebsite contextRef="C000200825_ClassMember" id="ixv-6620">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000200825_ClassMember" id="ixv-6623">1-800-544-3455</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000200825_ClassMember" id="ixv-6626">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000200825_ClassMember" id="ixv-6633">&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 $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:51%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity&#xae; SAI Tax-Free Bond Fund&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:21%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$ &lt;/span&gt;26&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:27%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;0.25&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:ExpensesTextBlock>
    <oef:ExpensesPaidAmt
      contextRef="C000200825_ClassMember"
      decimals="0"
      id="ixv-144307"
      unitRef="usd">26</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000200825_ClassMember"
      decimals="INF"
      id="ixv-144308"
      unitRef="pure">0.0025</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000200825_ClassMember" id="ixv-6675">&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. tax-exempt municipal bonds notched a strong gain for the 12 months ending January 31, 2026, bolstered by a second-half rally driven by three policy interest-rate cuts by the Federal Reserve since September, moderating muni supply and firming investor demand.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Against this backdrop, the fund's yield-curve positioning, helped by an underweight in longer-term bonds, contributed to performance versus the Bloomberg 3+ Year Non-AMT Municipal 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;In contrast, the fund had less "carry" than the index, meaning its holdings earned less income, which detracted from relative performance.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Pricing factors also crimped the relative result. Fund holdings are priced by a third-party pricing service and validated daily by Fidelity Management &amp;amp; Research's fair-value processes. Securities within the index, however, are priced by the index provider. These two approaches employ somewhat different methodologies in estimating the prices of municipal securities, most of which trade infrequently.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity 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 exposure to municipal bonds issued by Walker County Development Authority (GA) tied to McLemore Hotel &amp;amp; Resort further detracted, as the securities slumped after a missed debt-service deposit eroded investor confidence in the project's revenue stability.&#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;During the year, the portfolio management team reduced the fund's exposure to 20+-year bonds and lower-quality securities, and pared back exposure to the health care and higher education sectors.&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="C000200825_ClassMember" id="ixv-6699">How did the Fund perform over the life of Fund?

 &#160;&#160;
CUMULATIVE PERFORMANCE
October 2, 2018 through January 31, 2026. 
Initial investment of $10,000.
Fidelity&#xae; SAI Tax-Free Bond Fund


$10,000

$10,258


$11,251


$11,569


$11,392


$10,988


$11,433


$11,705


$12,240



Bloomberg 3+ Year Non-AMT Municipal Bond Index


$10,000

$10,261


$11,226


$11,714


$11,470


$11,050


$11,373


$11,589


$12,141



Bloomberg Municipal Bond Index


$10,000

$10,244


$11,130


$11,577


$11,358


$10,989


$11,308


$11,543


$12,086



&#160;

2018

2019

2020

2021

2022

2023

2024

2025

2026









&#160;
</oef:LineGraphTableTextBlock>
    <oef:LineGraphAndTableMeasureName contextRef="C000200825_LG_ClassMember_9YR" id="ixv-6718">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity&#xae; SAI Tax-Free Bond Fund&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000200825_ClassMember_AsOf_2018"
      decimals="0"
      id="ixv-144309"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000200825_ClassMember_AsOf_2019"
      decimals="0"
      id="ixv-144310"
      unitRef="usd">10258</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000200825_ClassMember_AsOf_2020"
      decimals="0"
      id="ixv-144311"
      unitRef="usd">11251</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000200825_ClassMember_AsOf_2021"
      decimals="0"
      id="ixv-144312"
      unitRef="usd">11569</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000200825_ClassMember_AsOf_2022"
      decimals="0"
      id="ixv-144313"
      unitRef="usd">11392</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000200825_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-144314"
      unitRef="usd">10988</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000200825_ClassMember_AsOf_2024"
      decimals="0"
      id="ixv-144315"
      unitRef="usd">11433</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000200825_ClassMember_AsOf_2025"
      decimals="0"
      id="ixv-144316"
      unitRef="usd">11705</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000200825_ClassMember_AsOf_2026"
      decimals="0"
      id="ixv-144317"
      unitRef="usd">12240</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000200825_LG_1_AdditionalIndexMember_9YR"
      id="ixv-6759">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg 3+ Year Non-AMT Municipal Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000200825_1_AdditionalIndexMember_AsOf_2018"
      decimals="0"
      id="ixv-144318"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000200825_1_AdditionalIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-144319"
      unitRef="usd">10261</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000200825_1_AdditionalIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-144320"
      unitRef="usd">11226</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000200825_1_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-144321"
      unitRef="usd">11714</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000200825_1_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-144322"
      unitRef="usd">11470</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000200825_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-144323"
      unitRef="usd">11050</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000200825_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-144324"
      unitRef="usd">11373</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000200825_1_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-144325"
      unitRef="usd">11589</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000200825_1_AdditionalIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-144326"
      unitRef="usd">12141</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000200825_LG_2_AdditionalIndexMember_9YR"
      id="ixv-6800">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg Municipal Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000200825_2_AdditionalIndexMember_AsOf_2018"
      decimals="0"
      id="ixv-144327"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000200825_2_AdditionalIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-144328"
      unitRef="usd">10244</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000200825_2_AdditionalIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-144329"
      unitRef="usd">11130</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000200825_2_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-144330"
      unitRef="usd">11577</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000200825_2_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-144331"
      unitRef="usd">11358</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000200825_2_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-144332"
      unitRef="usd">10989</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000200825_2_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-144333"
      unitRef="usd">11308</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000200825_2_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-144334"
      unitRef="usd">11543</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000200825_2_AdditionalIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-144335"
      unitRef="usd">12086</oef:AccmVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000200825_ClassMember" id="ixv-6887">AVERAGE ANNUAL TOTAL RETURNS:

&#160;

1 Year

5 Year

Life of Fund&#160;A


Fidelity&#xae; SAI Tax-Free Bond Fund

4.57%

1.13%

2.79%


Bloomberg 3+ Year Non-AMT Municipal Bond Index

4.77%


0.72%


2.68%


Bloomberg Municipal Bond Index

4.70%


0.86%


2.62%




A&#160; &#160;From October 2, 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="C000200825_NoLoadClassMember_1YR"
      decimals="INF"
      id="ixv-144336"
      unitRef="pure">0.0457</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000200825_NoLoadClassMember_5YR"
      decimals="INF"
      id="ixv-144337"
      unitRef="pure">0.0113</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000200825_NoLoadClassMember_2025-02-01_2026-01-31"
      decimals="INF"
      id="ixv-144338"
      unitRef="pure">0.0279</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000200825_0_AdditionalIndexMember_1YR"
      decimals="INF"
      id="ixv-144339"
      unitRef="pure">0.0477</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000200825_0_AdditionalIndexMember_5YR"
      decimals="INF"
      id="ixv-144340"
      unitRef="pure">0.0072</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000200825_0_AdditionalIndexMember_LOC"
      decimals="INF"
      id="ixv-144341"
      unitRef="pure">0.0268</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000200825_1_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-144342"
      unitRef="pure">0.0470</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000200825_1_BBIndexMember_5YR"
      decimals="INF"
      id="ixv-144343"
      unitRef="pure">0.0086</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000200825_1_BBIndexMember_LOC"
      decimals="INF"
      id="ixv-144344"
      unitRef="pure">0.0262</oef:AvgAnnlRtrPct>
    <oef:PerfInceptionDate
      contextRef="C000200825_Perf_2018-10-02_ClassMember"
      id="ixv-6956">2018-10-02</oef:PerfInceptionDate>
    <oef:UpdPerfInfoLocationTextBlock contextRef="C000200825_ClassMember" id="ixv-6966">&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="C000200825_ClassMember" id="ixv-6978">&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="C000200825_ClassMember" id="ixv-6982">&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="C000200825_ClassMember" id="ixv-6988">&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 January 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;$&lt;/span&gt;5,341,486,011&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;1,727&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;13,699,031&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;12&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: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;/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="C000200825_InstantMember"
      decimals="0"
      id="ixv-144345"
      unitRef="usd">5341486011</us-gaap:AssetsNet>
    <oef:HoldingsCount
      contextRef="C000200825_InstantMember"
      decimals="INF"
      id="ixv-144346"
      unitRef="holding">1727</oef:HoldingsCount>
    <oef:AdvisoryFeesPaidAmt
      contextRef="C000200825_ClassMember"
      decimals="0"
      id="ixv-144347"
      unitRef="usd">13699031</oef:AdvisoryFeesPaidAmt>
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      contextRef="C000200825_ClassMember"
      decimals="INF"
      id="ixv-144348"
      unitRef="pure">0.12</us-gaap:InvestmentCompanyPortfolioTurnover>
    <oef:HoldingsTableTextBlock contextRef="C000200825_ClassMember" id="ixv-7063">
&#160;
REVENUE SOURCES
 (% of Fund's net assets)


General Obligations

34.4

&#160;


Health Care

12.9

&#160;


Special Tax

11.2

&#160;


Electric Utilities

7.9

&#160;


Transportation

7.7

&#160;


Education

5.4

&#160;


Housing

5.3

&#160;


Water &amp; Sewer

5.1

&#160;


Others(Individually Less Than 5%)

1.4

&#160;


91.3

&#160;


&#160;




&#160;
AAA

5.5


AA

45.2


A

30.8


BBB

5.6


BB

1.0


B

0.2


Not Rated

3.0


Short-Term Investments and Net Other Assets (Liabilities)

8.7




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;



&#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 - 45.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

A - 30.8&#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;

BBB - 5.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BB - 1.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

B - 0.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Not Rated - 3.0&#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;

Short-Term Investments and Net Other Assets (Liabilities) - 8.7


&#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;
TOP STATES
(% of Fund's net assets)


New York

12.8


Texas

11.3


Illinois

7.4


Alabama

5.3


New Jersey

5.2


&#160;

&#160;




&#160;
</oef:HoldingsTableTextBlock>
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    <oef:PctOfNav
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    <oef:PctOfNav
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      unitRef="pure">0.054</oef:PctOfNav>
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      unitRef="pure">0.053</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-144356"
      unitRef="pure">0.051</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000200825_RS_8_Member"
      decimals="INF"
      id="ixv-144357"
      unitRef="pure">0.014</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000200825_QD_AAA_Member"
      decimals="INF"
      id="ixv-144358"
      unitRef="pure">0.055</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000200825_QD_AA_Member"
      decimals="INF"
      id="ixv-144359"
      unitRef="pure">0.452</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000200825_QD_A_Member"
      decimals="INF"
      id="ixv-144360"
      unitRef="pure">0.308</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000200825_QD_BBB_Member"
      decimals="INF"
      id="ixv-144361"
      unitRef="pure">0.056</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000200825_QD_BB_Member"
      decimals="INF"
      id="ixv-144362"
      unitRef="pure">0.010</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000200825_QD_B_Member"
      decimals="INF"
      id="ixv-144363"
      unitRef="pure">0.002</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000200825_QD_NotRated_Member"
      decimals="INF"
      id="ixv-144364"
      unitRef="pure">0.030</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-144365"
      unitRef="pure">0.087</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000200825_TS_0_Member"
      decimals="INF"
      id="ixv-144366"
      unitRef="pure">0.128</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000200825_TS_1_Member"
      decimals="INF"
      id="ixv-144367"
      unitRef="pure">0.113</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000200825_TS_2_Member"
      decimals="INF"
      id="ixv-144368"
      unitRef="pure">0.074</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000200825_TS_3_Member"
      decimals="INF"
      id="ixv-144369"
      unitRef="pure">0.053</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000200825_TS_4_Member"
      decimals="INF"
      id="ixv-144370"
      unitRef="pure">0.052</oef:PctOfNav>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-7404">2026-01-31</dei:DocumentPeriodEndDate>
    <oef:FundName contextRef="C000235216_ClassMember" id="ixv-7416">Fidelity&#xae; SAI Sustainable Municipal Income Fund</oef:FundName>
    <oef:ClassName contextRef="C000235216_ClassMember" id="ixv-7419">Fidelity&#xae; SAI Sustainable Municipal Income Fund</oef:ClassName>
    <dei:TradingSymbol contextRef="C000235216_ClassMember" id="ixv-7423">FASWX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000235216_ClassMember" id="ixv-7442">This annual shareholder report contains information about Fidelity&#xae; SAI Sustainable Municipal Income Fund for the period February 1, 2025 to January 31, 2026.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000235216_ClassMember" id="ixv-7444">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000235216_ClassMember" id="ixv-7449">You can find additional information about the Fund at fundresearch.fidelity.com/prospectus/sec. You can also request this information by contacting us at 1-800-544-3455 or by sending an e-mail to fidfunddocuments@fidelity.com.</oef:AddlInfoTextBlock>
    <oef:AddlInfoWebsite contextRef="C000235216_ClassMember" id="ixv-7451">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000235216_ClassMember" id="ixv-7454">1-800-544-3455</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000235216_ClassMember" id="ixv-7457">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000235216_ClassMember" id="ixv-7464">&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 $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:51%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity&#xae; SAI Sustainable Municipal Income Fund&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:21%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$ &lt;/span&gt;37&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="C000235216_ClassMember"
      decimals="0"
      id="ixv-144371"
      unitRef="usd">37</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000235216_ClassMember"
      decimals="INF"
      id="ixv-144372"
      unitRef="pure">0.0036</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000235216_ClassMember" id="ixv-7506">&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. tax-exempt municipal bonds notched a strong gain for the 12 months ending January 31, 2026, bolstered by a second-half rally driven by three policy interest-rate cuts by the Federal Reserve since September, moderating muni supply and firming investor demand.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Against this backdrop, the fund's exposure to certain lower-coupon bonds, especially those issued by the Metropolitan Government of Nashville and Davidson County, contributed to performance versus the Bloomberg 3+ Year Municipal 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 contributed as well. Specifically, an overweight in the 10-year part of the curve and underweight in the 20-year part helped, as the muni yield curve steepened during the 12-month period.&#160;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;In contrast, pricing factors modestly detracted from relative performance. Fund holdings are priced by a third-party pricing service and validated daily by Fidelity Management &amp;amp; Research's fair-value processes. Securities within the index, however, are priced by the index provider. These two approaches employ somewhat different methodologies in estimating the prices of municipal securities, most of which trade infrequently.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity 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 also produced less "carry" than the index, which slightly crimped 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;During the year, the portfolio management team added exposure to lower-coupon bonds at a discount to par when they felt appropriate opportunities arose.&#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:12px;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:12px;color:#000000;font-style:italic;font-weight:normal;"&gt;Application of FMR's environmental, social, and governance (ESG) 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;span style="line-height:13px;"&gt;&#160;&lt;/span&gt;&lt;div style="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;/div&gt;</oef:FactorsAffectingPerfTextBlock>
    <oef:LineGraphTableTextBlock contextRef="C000235216_ClassMember" id="ixv-7536">How did the Fund perform over the life of Fund?

 &#160;&#160;
CUMULATIVE PERFORMANCE
April 13, 2022 through January 31, 2026. 
Initial investment of $10,000.
Fidelity&#xae; SAI Sustainable Municipal Income Fund


$10,000

$10,356


$10,796


$10,992


$11,572



Bloomberg 3+ Year Municipal Bond Index


$10,000

$10,167


$10,469


$10,674


$11,185



Bloomberg Municipal Bond Index


$10,000

$10,168


$10,463


$10,681


$11,183



&#160;

2022

2023

2024

2025

2026









&#160;
</oef:LineGraphTableTextBlock>
    <oef:LineGraphAndTableMeasureName contextRef="C000235216_LG_ClassMember_5YR" id="ixv-7555">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity&#xae; SAI Sustainable Municipal Income Fund&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000235216_ClassMember_AsOf_2022"
      decimals="0"
      id="ixv-144373"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235216_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-144374"
      unitRef="usd">10356</oef:AccmVal>
    <oef:AccmVal
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      decimals="0"
      id="ixv-144375"
      unitRef="usd">10796</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235216_ClassMember_AsOf_2025"
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      id="ixv-144376"
      unitRef="usd">10992</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235216_ClassMember_AsOf_2026"
      decimals="0"
      id="ixv-144377"
      unitRef="usd">11572</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000235216_LG_1_AdditionalIndexMember_5YR"
      id="ixv-7580">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg 3+ Year Municipal Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000235216_1_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-144378"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235216_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-144379"
      unitRef="usd">10167</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235216_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-144380"
      unitRef="usd">10469</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235216_1_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-144381"
      unitRef="usd">10674</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235216_1_AdditionalIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-144382"
      unitRef="usd">11185</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000235216_LG_2_AdditionalIndexMember_5YR"
      id="ixv-7605">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg Municipal Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000235216_2_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-144383"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235216_2_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-144384"
      unitRef="usd">10168</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235216_2_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-144385"
      unitRef="usd">10463</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235216_2_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-144386"
      unitRef="usd">10681</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235216_2_AdditionalIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-144387"
      unitRef="usd">11183</oef:AccmVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000235216_ClassMember" id="ixv-7664">AVERAGE ANNUAL TOTAL RETURNS:

&#160;

1 Year

Life of Fund&#160;A


Fidelity&#xae; SAI Sustainable Municipal Income Fund

5.28%

3.91%


Bloomberg 3+ Year Municipal Bond Index

4.78%


2.99%


Bloomberg Municipal Bond Index

4.70%


2.98%




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

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

&#160;


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





</oef:AvgAnnlRtrTableTextBlock>
    <oef:AvgAnnlRtrPct
      contextRef="C000235216_NoLoadClassMember_1YR"
      decimals="INF"
      id="ixv-144388"
      unitRef="pure">0.0528</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235216_NoLoadClassMember_2025-02-01_2026-01-31"
      decimals="INF"
      id="ixv-144389"
      unitRef="pure">0.0391</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235216_0_AdditionalIndexMember_1YR"
      decimals="INF"
      id="ixv-144390"
      unitRef="pure">0.0478</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235216_0_AdditionalIndexMember_LOC"
      decimals="INF"
      id="ixv-144391"
      unitRef="pure">0.0299</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235216_1_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-144392"
      unitRef="pure">0.0470</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235216_1_BBIndexMember_LOC"
      decimals="INF"
      id="ixv-144393"
      unitRef="pure">0.0298</oef:AvgAnnlRtrPct>
    <oef:PerfInceptionDate
      contextRef="C000235216_Perf_2022-04-13_ClassMember"
      id="ixv-7719">2022-04-13</oef:PerfInceptionDate>
    <oef:UpdPerfInfoLocationTextBlock contextRef="C000235216_ClassMember" id="ixv-7729">&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="C000235216_ClassMember" id="ixv-7741">&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="C000235216_ClassMember" id="ixv-7745">&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="C000235216_ClassMember" id="ixv-7751">&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 January 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;$&lt;/span&gt;77,623,729&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;414&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;170,674&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;10&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: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;/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="C000235216_InstantMember"
      decimals="0"
      id="ixv-144394"
      unitRef="usd">77623729</us-gaap:AssetsNet>
    <oef:HoldingsCount
      contextRef="C000235216_InstantMember"
      decimals="INF"
      id="ixv-144395"
      unitRef="holding">414</oef:HoldingsCount>
    <oef:AdvisoryFeesPaidAmt
      contextRef="C000235216_ClassMember"
      decimals="0"
      id="ixv-144396"
      unitRef="usd">170674</oef:AdvisoryFeesPaidAmt>
    <us-gaap:InvestmentCompanyPortfolioTurnover
      contextRef="C000235216_ClassMember"
      decimals="INF"
      id="ixv-144397"
      unitRef="pure">0.10</us-gaap:InvestmentCompanyPortfolioTurnover>
    <oef:HoldingsTableTextBlock contextRef="C000235216_ClassMember" id="ixv-7826">
&#160;
REVENUE SOURCES
 (% of Fund's net assets)


General Obligations

34.3

&#160;


Health Care

14.3

&#160;


Water &amp; Sewer

11.7

&#160;


Education

10.5

&#160;


Electric Utilities

10.3

&#160;


Housing

7.1

&#160;


Special Tax

6.5

&#160;


Others(Individually Less Than 5%)

3.4

&#160;


98.1

&#160;


&#160;




&#160;
AAA

13.5


AA

56.6


A

24.0


BBB

3.5


BB

0.3


Not Rated

0.2


Short-Term Investments and Net Other Assets (Liabilities)

1.9




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

AAA - 13.5&#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;

AA - 56.6&#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;

A - 24.0&#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;

BBB - 3.5&#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;

BB - 0.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Not Rated - 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;

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


&#160;


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




&#160;
&#160;
&#160;
TOP STATES
(% of Fund's net assets)


Texas

11.7


New York

9.5


Alabama

8.2


Georgia

6.8


Illinois

6.6


&#160;

&#160;




&#160;
</oef:HoldingsTableTextBlock>
    <oef:PctOfNav
      contextRef="C000235216_RS_0_Member"
      decimals="INF"
      id="ixv-144398"
      unitRef="pure">0.343</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235216_RS_1_Member"
      decimals="INF"
      id="ixv-144399"
      unitRef="pure">0.143</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235216_RS_2_Member"
      decimals="INF"
      id="ixv-144400"
      unitRef="pure">0.117</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235216_RS_3_Member"
      decimals="INF"
      id="ixv-144401"
      unitRef="pure">0.105</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235216_RS_4_Member"
      decimals="INF"
      id="ixv-144402"
      unitRef="pure">0.103</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235216_RS_5_Member"
      decimals="INF"
      id="ixv-144403"
      unitRef="pure">0.071</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235216_RS_6_Member"
      decimals="INF"
      id="ixv-144404"
      unitRef="pure">0.065</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235216_RS_7_Member"
      decimals="INF"
      id="ixv-144405"
      unitRef="pure">0.034</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235216_QD_AAA_Member"
      decimals="INF"
      id="ixv-144406"
      unitRef="pure">0.135</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235216_QD_AA_Member"
      decimals="INF"
      id="ixv-144407"
      unitRef="pure">0.566</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235216_QD_A_Member"
      decimals="INF"
      id="ixv-144408"
      unitRef="pure">0.240</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235216_QD_BBB_Member"
      decimals="INF"
      id="ixv-144409"
      unitRef="pure">0.035</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235216_QD_BB_Member"
      decimals="INF"
      id="ixv-144410"
      unitRef="pure">0.003</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235216_QD_NotRated_Member"
      decimals="INF"
      id="ixv-144411"
      unitRef="pure">0.002</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235216_QD_ShortTermInvestmentsandNetOtherAssetsLiabilities_Member"
      decimals="INF"
      id="ixv-144412"
      unitRef="pure">0.019</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235216_TS_0_Member"
      decimals="INF"
      id="ixv-144413"
      unitRef="pure">0.117</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235216_TS_1_Member"
      decimals="INF"
      id="ixv-144414"
      unitRef="pure">0.095</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235216_TS_2_Member"
      decimals="INF"
      id="ixv-144415"
      unitRef="pure">0.082</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235216_TS_3_Member"
      decimals="INF"
      id="ixv-144416"
      unitRef="pure">0.068</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235216_TS_4_Member"
      decimals="INF"
      id="ixv-144417"
      unitRef="pure">0.066</oef:PctOfNav>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-8145">2026-01-31</dei:DocumentPeriodEndDate>
    <oef:FundName contextRef="C000235213_ClassMember" id="ixv-8157">Fidelity&#xae; SAI Sustainable Conservative Income Municipal Bond Fund</oef:FundName>
    <oef:ClassName contextRef="C000235213_ClassMember" id="ixv-8160">Fidelity&#xae; SAI Sustainable Conservative Income Municipal Bond Fund</oef:ClassName>
    <dei:TradingSymbol contextRef="C000235213_ClassMember" id="ixv-8164">FASYX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000235213_ClassMember" id="ixv-8183">This annual shareholder report contains information about Fidelity&#xae; SAI Sustainable Conservative Income Municipal Bond Fund for the period February 1, 2025 to January 31, 2026.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000235213_ClassMember" id="ixv-8185">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000235213_ClassMember" id="ixv-8190">You can find additional information about the Fund at fundresearch.fidelity.com/prospectus/sec. You can also request this information by contacting us at 1-800-544-3455 or by sending an e-mail to fidfunddocuments@fidelity.com.</oef:AddlInfoTextBlock>
    <oef:AddlInfoWebsite contextRef="C000235213_ClassMember" id="ixv-8192">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000235213_ClassMember" id="ixv-8195">1-800-544-3455</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000235213_ClassMember" id="ixv-8198">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000235213_ClassMember" id="ixv-8205">&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 $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:51%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity&#xae; SAI Sustainable Conservative Income Municipal Bond Fund&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:21%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$ &lt;/span&gt;20&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:27%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;0.20&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:ExpensesTextBlock>
    <oef:ExpensesPaidAmt
      contextRef="C000235213_ClassMember"
      decimals="0"
      id="ixv-144418"
      unitRef="usd">20</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000235213_ClassMember"
      decimals="INF"
      id="ixv-144419"
      unitRef="pure">0.0020</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000235213_ClassMember" id="ixv-8247">&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. tax-exempt municipal bonds notched a strong gain for the 12 months ending January 31, 2026, bolstered by a second-half rally driven by three policy interest-rate cuts by the Federal Reserve since September, moderating muni supply and firming investor demand.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Against this backdrop, the fund's "carry" advantage, meaning its proportionately larger stake in higher-yielding bonds, contributed to performance versus the Bloomberg Municipal 1 Year (1-2Y) Bond Index for the fiscal year.&#160;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;An overweight in lower-coupon par bonds was also helpful.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;In contrast, the fund's yield-curve positioning, specifically its underweight in the two-year part of the curve, detracted from performance versus the index.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;During the year, the portfolio management team reduced the fund's exposure to the health care and higher education sectors and pared back exposure to lower-quality securities.&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 (ESG) 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;span style="line-height:13px;"&gt;&#160;&lt;/span&gt;&lt;div style="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;/div&gt;</oef:FactorsAffectingPerfTextBlock>
    <oef:LineGraphTableTextBlock contextRef="C000235213_ClassMember" id="ixv-8275">How did the Fund perform over the life of Fund?

 &#160;&#160;
CUMULATIVE PERFORMANCE
June 16, 2022 through January 31, 2026. 
Initial investment of $10,000.
Fidelity&#xae; SAI Sustainable Conservative Income Municipal Bond Fund


$10,000

$10,107


$10,449


$10,814


$11,170



Fidelity Conservative Income Municipal Bond Composite Index&#x2120;


$10,000

$10,122


$10,424


$10,773


$11,112



Bloomberg Municipal Bond 1 Year (1-2 Y) Index


$10,000

$10,122


$10,374


$10,715


$11,090



Bloomberg Municipal Bond Index


$10,000

$10,467


$10,771


$10,995


$11,512



&#160;

2022

2023

2024

2025

2026









&#160;
</oef:LineGraphTableTextBlock>
    <oef:LineGraphAndTableMeasureName contextRef="C000235213_LG_ClassMember_5YR" id="ixv-8294">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity&#xae; SAI Sustainable Conservative Income Municipal Bond Fund&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000235213_ClassMember_AsOf_2022"
      decimals="0"
      id="ixv-144420"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235213_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-144421"
      unitRef="usd">10107</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235213_ClassMember_AsOf_2024"
      decimals="0"
      id="ixv-144422"
      unitRef="usd">10449</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235213_ClassMember_AsOf_2025"
      decimals="0"
      id="ixv-144423"
      unitRef="usd">10814</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235213_ClassMember_AsOf_2026"
      decimals="0"
      id="ixv-144424"
      unitRef="usd">11170</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000235213_LG_1_AdditionalIndexMember_5YR"
      id="ixv-8319">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity Conservative Income Municipal Bond Composite Index&#x2120;&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000235213_1_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-144425"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235213_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-144426"
      unitRef="usd">10122</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235213_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-144427"
      unitRef="usd">10424</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235213_1_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-144428"
      unitRef="usd">10773</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235213_1_AdditionalIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-144429"
      unitRef="usd">11112</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000235213_LG_2_AdditionalIndexMember_5YR"
      id="ixv-8344">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg Municipal Bond 1 Year (1-2 Y) Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000235213_2_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-144430"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235213_2_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-144431"
      unitRef="usd">10122</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235213_2_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-144432"
      unitRef="usd">10374</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235213_2_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-144433"
      unitRef="usd">10715</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235213_2_AdditionalIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-144434"
      unitRef="usd">11090</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000235213_0_LG_BBIndexMember_5YR"
      id="ixv-8369">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg Municipal Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000235213_0_BBIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-144435"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235213_0_BBIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-144436"
      unitRef="usd">10467</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235213_0_BBIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-144437"
      unitRef="usd">10771</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235213_0_BBIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-144438"
      unitRef="usd">10995</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235213_0_BBIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-144439"
      unitRef="usd">11512</oef:AccmVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000235213_ClassMember" id="ixv-8427">AVERAGE ANNUAL TOTAL RETURNS:

&#160;

1 Year

Life of Fund&#160;A


Fidelity&#xae; SAI Sustainable Conservative Income Municipal Bond Fund

3.30%

3.10%


Fidelity Conservative Income Municipal Bond Composite Index&#x2120;

3.14%


2.95%


Bloomberg Municipal Bond 1 Year (1-2 Y) Index

3.50%


2.89%


Bloomberg Municipal Bond Index

4.70%


3.95%




A&#160; &#160;From June 16, 2022

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

&#160;


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





</oef:AvgAnnlRtrTableTextBlock>
    <oef:AvgAnnlRtrPct
      contextRef="C000235213_NoLoadClassMember_1YR"
      decimals="INF"
      id="ixv-144440"
      unitRef="pure">0.0330</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235213_NoLoadClassMember_2025-02-01_2026-01-31"
      decimals="INF"
      id="ixv-144441"
      unitRef="pure">0.0310</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235213_0_AdditionalIndexMember_1YR"
      decimals="INF"
      id="ixv-144442"
      unitRef="pure">0.0314</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235213_0_AdditionalIndexMember_LOC"
      decimals="INF"
      id="ixv-144443"
      unitRef="pure">0.0295</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235213_1_AdditionalIndexMember_1YR"
      decimals="INF"
      id="ixv-144444"
      unitRef="pure">0.0350</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235213_1_AdditionalIndexMember_LOC"
      decimals="INF"
      id="ixv-144445"
      unitRef="pure">0.0289</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235213_2_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-144446"
      unitRef="pure">0.0470</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235213_2_BBIndexMember_LOC"
      decimals="INF"
      id="ixv-144447"
      unitRef="pure">0.0395</oef:AvgAnnlRtrPct>
    <oef:PerfInceptionDate
      contextRef="C000235213_Perf_2022-06-16_ClassMember"
      id="ixv-8493">2022-06-16</oef:PerfInceptionDate>
    <oef:UpdPerfInfoLocationTextBlock contextRef="C000235213_ClassMember" id="ixv-8503">&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="C000235213_ClassMember" id="ixv-8515">&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="C000235213_ClassMember" id="ixv-8519">&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="C000235213_ClassMember" id="ixv-8525">&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 January 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;$&lt;/span&gt;24,543,449&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;137&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;43,826&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="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;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;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;/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="C000235213_InstantMember"
      decimals="0"
      id="ixv-144448"
      unitRef="usd">24543449</us-gaap:AssetsNet>
    <oef:HoldingsCount
      contextRef="C000235213_InstantMember"
      decimals="INF"
      id="ixv-144449"
      unitRef="holding">137</oef:HoldingsCount>
    <oef:AdvisoryFeesPaidAmt
      contextRef="C000235213_ClassMember"
      decimals="0"
      id="ixv-144450"
      unitRef="usd">43826</oef:AdvisoryFeesPaidAmt>
    <us-gaap:InvestmentCompanyPortfolioTurnover
      contextRef="C000235213_ClassMember"
      decimals="INF"
      id="ixv-144451"
      unitRef="pure">0.70</us-gaap:InvestmentCompanyPortfolioTurnover>
    <oef:HoldingsTableTextBlock contextRef="C000235213_ClassMember" id="ixv-8600">
&#160;
REVENUE SOURCES
 (% of Fund's net assets)


Electric Utilities

21.4

&#160;


General Obligations

16.3

&#160;


Health Care

14.8

&#160;


Housing

12.8

&#160;


Resource Recovery

10.9

&#160;


Industrial Development

8.5

&#160;


Synthetics

7.7

&#160;


Others(Individually Less Than 5%)

7.3

&#160;


99.7

&#160;


&#160;




&#160;
AAA

4.3


AA

32.1


A

57.4


BBB

0.6


Not Rated

5.3


Short-Term Investments and Net Other Assets (Liabilities)

0.3




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

AAA - 4.3&#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;

AA - 32.1&#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;

A - 57.4&#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 - 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;

Not Rated - 5.3&#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;

Short-Term Investments and Net Other Assets (Liabilities) - 0.3


&#160;


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




&#160;
&#160;
&#160;
TOP STATES
(% of Fund's net assets)


Georgia

10.2


New York

9.7


Florida

8.7


Texas

7.1


Tennessee

6.8


&#160;

&#160;




&#160;
</oef:HoldingsTableTextBlock>
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    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-8906">2026-01-31</dei:DocumentPeriodEndDate>
    <oef:FundName contextRef="C000245667_ClassMember" id="ixv-8918">Fidelity&#xae; SAI Conservative Income Municipal Bond Fund</oef:FundName>
    <oef:ClassName contextRef="C000245667_ClassMember" id="ixv-8921">Fidelity&#xae; SAI Conservative Income Municipal Bond Fund</oef:ClassName>
    <dei:TradingSymbol contextRef="C000245667_ClassMember" id="ixv-8925">FSMJX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000245667_ClassMember" id="ixv-8944">This annual shareholder report contains information about Fidelity&#xae; SAI Conservative Income Municipal Bond Fund for the period February 1, 2025 to January 31, 2026.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000245667_ClassMember" id="ixv-8946">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000245667_ClassMember" id="ixv-8951">You can find additional information about the Fund at fundresearch.fidelity.com/prospectus/sec. You can also request this information by contacting us at 1-800-544-3455 or by sending an e-mail to fidfunddocuments@fidelity.com.</oef:AddlInfoTextBlock>
    <oef:AddlInfoWebsite contextRef="C000245667_ClassMember" id="ixv-8953">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000245667_ClassMember" id="ixv-8956">1-800-544-3455</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000245667_ClassMember" id="ixv-8959">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000245667_ClassMember" id="ixv-8966">&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 $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:51%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity&#xae; SAI Conservative Income Municipal Bond Fund&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:21%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$ &lt;/span&gt;20&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:27%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;0.20&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:ExpensesTextBlock>
    <oef:ExpensesPaidAmt
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      id="ixv-144471"
      unitRef="usd">20</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
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      id="ixv-144472"
      unitRef="pure">0.0020</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000245667_ClassMember" id="ixv-9008">&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. tax-exempt municipal bonds notched a strong gain for the 12 months ending January 31, 2026, bolstered by a second-half rally driven by three policy interest-rate cuts by the Federal Reserve since September, moderating muni supply and firming investor demand.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Against this backdrop, the fund's yield-curve positioning, specifically its underweight in the two-year part of the curve, detracted from performance versus the Bloomberg Municipal 1 Year (1-2 Y) 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;In contrast, the fund's "carry" advantage, meaning its proportionately larger stake in higher-yielding bonds, contributed to relative performance.&#160;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;An overweight in lower-coupon par bonds was also helpful.&#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;During the year, the portfolio management team reduced the fund's exposure to the health care and higher education sectors and pared back exposure to lower-quality securities.&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="C000245667_ClassMember" id="ixv-9029">How did the Fund perform over the life of Fund?

 &#160;&#160;
CUMULATIVE PERFORMANCE
November 6, 2023 through January 31, 2026. 
Initial investment of $10,000.
Fidelity&#xae; SAI Conservative Income Municipal Bond Fund


$10,000

$10,136


$10,485


$10,824



Fidelity Conservative Income Municipal Bond Composite Index&#x2120;


$10,000

$10,120


$10,459


$10,787



Bloomberg Municipal Bond 1 Year (1-2 Y) Index


$10,000

$10,158


$10,492


$10,859



Bloomberg Municipal Bond Index


$10,000

$10,616


$10,837


$11,346



&#160;

2023

2024

2025

2026









&#160;
</oef:LineGraphTableTextBlock>
    <oef:LineGraphAndTableMeasureName contextRef="C000245667_LG_ClassMember_4YR" id="ixv-9048">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity&#xae; SAI Conservative Income Municipal Bond Fund&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000245667_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-144473"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
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    <oef:AccmVal
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      id="ixv-144475"
      unitRef="usd">10485</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000245667_ClassMember_AsOf_2026"
      decimals="0"
      id="ixv-144476"
      unitRef="usd">10824</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000245667_LG_1_AdditionalIndexMember_4YR"
      id="ixv-9069">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity Conservative Income Municipal Bond Composite Index&#x2120;&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000245667_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-144477"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000245667_1_AdditionalIndexMember_AsOf_2024"
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      id="ixv-144478"
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    <oef:AccmVal
      contextRef="C000245667_1_AdditionalIndexMember_AsOf_2025"
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    <oef:AccmVal
      contextRef="C000245667_1_AdditionalIndexMember_AsOf_2026"
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      id="ixv-144480"
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    <oef:LineGraphAndTableMeasureName
      contextRef="C000245667_LG_2_AdditionalIndexMember_4YR"
      id="ixv-9090">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg Municipal Bond 1 Year (1-2 Y) Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000245667_2_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-144481"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000245667_2_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-144482"
      unitRef="usd">10158</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000245667_2_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-144483"
      unitRef="usd">10492</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000245667_2_AdditionalIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-144484"
      unitRef="usd">10859</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000245667_0_LG_BBIndexMember_4YR"
      id="ixv-9111">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg Municipal Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000245667_0_BBIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-144485"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000245667_0_BBIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-144486"
      unitRef="usd">10616</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000245667_0_BBIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-144487"
      unitRef="usd">10837</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000245667_0_BBIndexMember_AsOf_2026"
      decimals="0"
      id="ixv-144488"
      unitRef="usd">11346</oef:AccmVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000245667_ClassMember" id="ixv-9162">AVERAGE ANNUAL TOTAL RETURNS:

&#160;

1 Year

Life of Fund&#160;A


Fidelity&#xae; SAI Conservative Income Municipal Bond Fund

3.24%

3.60%


Fidelity Conservative Income Municipal Bond Composite Index&#x2120;

3.14%


3.44%


Bloomberg Municipal Bond 1 Year (1-2 Y) Index

3.50%


3.75%


Bloomberg Municipal Bond Index

4.70%


5.81%




A&#160; &#160;From November 6, 2023

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

&#160;


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





</oef:AvgAnnlRtrTableTextBlock>
    <oef:AvgAnnlRtrPct
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      decimals="INF"
      id="ixv-144489"
      unitRef="pure">0.0324</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000245667_NoLoadClassMember_2025-02-01_2026-01-31"
      decimals="INF"
      id="ixv-144490"
      unitRef="pure">0.0360</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000245667_0_AdditionalIndexMember_1YR"
      decimals="INF"
      id="ixv-144491"
      unitRef="pure">0.0314</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000245667_0_AdditionalIndexMember_LOC"
      decimals="INF"
      id="ixv-144492"
      unitRef="pure">0.0344</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000245667_1_AdditionalIndexMember_1YR"
      decimals="INF"
      id="ixv-144493"
      unitRef="pure">0.0350</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000245667_1_AdditionalIndexMember_LOC"
      decimals="INF"
      id="ixv-144494"
      unitRef="pure">0.0375</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000245667_2_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-144495"
      unitRef="pure">0.0470</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000245667_2_BBIndexMember_LOC"
      decimals="INF"
      id="ixv-144496"
      unitRef="pure">0.0581</oef:AvgAnnlRtrPct>
    <oef:PerfInceptionDate
      contextRef="C000245667_Perf_2023-11-06_ClassMember"
      id="ixv-9228">2023-11-06</oef:PerfInceptionDate>
    <oef:UpdPerfInfoLocationTextBlock contextRef="C000245667_ClassMember" id="ixv-9238">&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="C000245667_ClassMember" id="ixv-9250">&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="C000245667_ClassMember" id="ixv-9254">&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="C000245667_ClassMember" id="ixv-9260">&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 January 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;$&lt;/span&gt;1,536,920,320&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;458&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;3,249,190&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;64&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: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;/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-144497"
      unitRef="usd">1536920320</us-gaap:AssetsNet>
    <oef:HoldingsCount
      contextRef="C000245667_InstantMember"
      decimals="INF"
      id="ixv-144498"
      unitRef="holding">458</oef:HoldingsCount>
    <oef:AdvisoryFeesPaidAmt
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      decimals="0"
      id="ixv-144499"
      unitRef="usd">3249190</oef:AdvisoryFeesPaidAmt>
    <us-gaap:InvestmentCompanyPortfolioTurnover
      contextRef="C000245667_ClassMember"
      decimals="INF"
      id="ixv-144500"
      unitRef="pure">0.64</us-gaap:InvestmentCompanyPortfolioTurnover>
    <oef:HoldingsTableTextBlock contextRef="C000245667_ClassMember" id="ixv-9335">
&#160;
REVENUE SOURCES
 (% of Fund's net assets)


General Obligations

20.7

&#160;


Synthetics

18.0

&#160;


Resource Recovery

10.7

&#160;


Industrial Development

9.9

&#160;


Transportation

9.3

&#160;


Housing

8.6

&#160;


Electric Utilities

7.3

&#160;


Health Care

7.2

&#160;


Others(Individually Less Than 5%)

4.3

&#160;


96.0

&#160;


&#160;




&#160;
AAA

3.5


AA

29.8


A

43.0


BBB

7.6


Not Rated

12.1


Short-Term Investments and Net Other Assets (Liabilities)

4.0




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

AAA - 3.5&#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 - 29.8&#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;

A - 43.0&#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;

BBB - 7.6&#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;

Not Rated - 12.1&#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;

Short-Term Investments and Net Other Assets (Liabilities) - 4.0


&#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;
TOP STATES
(% of Fund's net assets)


Texas

13.9


New York

9.9


California

8.5


Florida

7.8


Pennsylvania

5.8


&#160;

&#160;




&#160;
</oef:HoldingsTableTextBlock>
    <oef:PctOfNav
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      id="ixv-144501"
      unitRef="pure">0.207</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000245667_RS_1_Member"
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    <oef:PctOfNav
      contextRef="C000245667_RS_2_Member"
      decimals="INF"
      id="ixv-144503"
      unitRef="pure">0.107</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000245667_RS_3_Member"
      decimals="INF"
      id="ixv-144504"
      unitRef="pure">0.099</oef:PctOfNav>
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      contextRef="C000245667_RS_4_Member"
      decimals="INF"
      id="ixv-144505"
      unitRef="pure">0.093</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000245667_RS_5_Member"
      decimals="INF"
      id="ixv-144506"
      unitRef="pure">0.086</oef:PctOfNav>
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      contextRef="C000245667_RS_6_Member"
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      id="ixv-144508"
      unitRef="pure">0.072</oef:PctOfNav>
    <oef:PctOfNav
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      id="ixv-144509"
      unitRef="pure">0.043</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000245667_QD_AAA_Member"
      decimals="INF"
      id="ixv-144510"
      unitRef="pure">0.035</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000245667_QD_AA_Member"
      decimals="INF"
      id="ixv-144511"
      unitRef="pure">0.298</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000245667_QD_A_Member"
      decimals="INF"
      id="ixv-144512"
      unitRef="pure">0.430</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000245667_QD_BBB_Member"
      decimals="INF"
      id="ixv-144513"
      unitRef="pure">0.076</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000245667_QD_NotRated_Member"
      decimals="INF"
      id="ixv-144514"
      unitRef="pure">0.121</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000245667_QD_ShortTermInvestmentsandNetOtherAssetsLiabilities_Member"
      decimals="INF"
      id="ixv-144515"
      unitRef="pure">0.040</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000245667_TS_0_Member"
      decimals="INF"
      id="ixv-144516"
      unitRef="pure">0.139</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000245667_TS_1_Member"
      decimals="INF"
      id="ixv-144517"
      unitRef="pure">0.099</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000245667_TS_2_Member"
      decimals="INF"
      id="ixv-144518"
      unitRef="pure">0.085</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000245667_TS_3_Member"
      decimals="INF"
      id="ixv-144519"
      unitRef="pure">0.078</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000245667_TS_4_Member"
      decimals="INF"
      id="ixv-144520"
      unitRef="pure">0.058</oef:PctOfNav>
</xbrl>
