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        <period>
            <instant>2025-08-31</instant>
        </period>
    </context>
    <context id="C000235231_GD_IE_Member">
        <entity>
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            <segment>
                <xbrldi:explicitMember dimension="oef:ClassAxis">fmr:C000235231Member</xbrldi:explicitMember>
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        <period>
            <instant>2025-08-31</instant>
        </period>
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    <context id="C000235231_GD_NL_Member">
        <entity>
            <identifier scheme="http://www.sec.gov/CIK">0000035315</identifier>
            <segment>
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        <period>
            <instant>2025-08-31</instant>
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    <context id="C000235231_GD_JP_Member">
        <entity>
            <identifier scheme="http://www.sec.gov/CIK">0000035315</identifier>
            <segment>
                <xbrldi:explicitMember dimension="oef:ClassAxis">fmr:C000235231Member</xbrldi:explicitMember>
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            <instant>2025-08-31</instant>
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    <context id="C000235231_GD_SE_Member">
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            <segment>
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            <instant>2025-08-31</instant>
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    <context id="C000235231_GD_IT_Member">
        <entity>
            <identifier scheme="http://www.sec.gov/CIK">0000035315</identifier>
            <segment>
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            <instant>2025-08-31</instant>
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            <instant>2025-08-31</instant>
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            <instant>2025-08-31</instant>
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            <instant>2025-08-31</instant>
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            <segment>
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    <context id="C000235229_QD_USGovernmentandUSGovernmentAgencyObligations_Member">
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    <dei:AmendmentFlag contextRef="Trust" id="ixv-213516">false</dei:AmendmentFlag>
    <dei:EntityCentralIndexKey contextRef="Trust" id="ixv-213517">0000035315</dei:EntityCentralIndexKey>
    <dei:EntityInvCompanyType contextRef="Trust" id="ixv-213518">N-1A</dei:EntityInvCompanyType>
    <dei:EntityRegistrantName contextRef="Trust" id="ixv-213519">Fidelity Salem Street Trust</dei:EntityRegistrantName>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-104">2025-08-31</dei:DocumentPeriodEndDate>
    <oef:FundName contextRef="C000235234_ClassMember" id="ixv-116">Fidelity&#xae; Sustainable Low Duration Bond Fund</oef:FundName>
    <oef:ClassName contextRef="C000235234_ClassMember" id="ixv-119">Fidelity&#xae; Sustainable Low Duration Bond Fund</oef:ClassName>
    <dei:TradingSymbol contextRef="C000235234_ClassMember" id="ixv-123">FAPGX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000235234_ClassMember" id="ixv-142">This annual shareholder report contains information about Fidelity&#xae; Sustainable Low Duration Bond Fund for the period September 1, 2024 to August 31, 2025.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000235234_ClassMember" id="ixv-144">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000235234_ClassMember" id="ixv-149">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="C000235234_ClassMember" id="ixv-151">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000235234_ClassMember" id="ixv-154">1-800-544-8544</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000235234_ClassMember" id="ixv-157">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000235234_ClassMember" id="ixv-164">&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:45%; 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:24%; 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:30%; 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 $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:45%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity&#xae; Sustainable Low Duration Bond Fund&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:24%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$ &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:30%; 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="C000235234_ClassMember"
      decimals="0"
      id="ixv-224569"
      unitRef="usd">26</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000235234_ClassMember"
      decimals="INF"
      id="ixv-224570"
      unitRef="pure">0.0025</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000235234_ClassMember" id="ixv-206">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What affected the Fund's performance this period?&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;U.S. taxable investment-grade bonds posted a solid advance for the 12 months ending August 31, 2025, navigating tariff-related uncertainty since late 2024 but buoyed by relatively stable consumer inflation, a resilient economy and the expectation of policy interest-rate cuts by the U.S. Federal Reserve in the second half of 2025.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Against this backdrop, the fund's strategy of holding short-term debt in high-quality corporations contributed to performance versus the all-U.S.-Treasury benchmark for the fiscal year. Within corporates, debt holdings among financial institutions, especially banks, and industrial firms, particularly in the consumer cyclical and consumer non-cyclical segments, added notable value.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Non-benchmark exposure to asset-backed securities, primarily car loan debt, also meaningfully contributed.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;In contrast, the fund's yield-curve positioning detracted from relative performance.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;A small allocation to cash was a modest drag as well.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;At period end, corporates made up about 48% of fund assets, down from roughly 60% a year ago. Exposure to U.S. Treasurys rose from about 26% to roughly 30% of assets during the fiscal year, while exposure to ABS was up from about 11% to 19% of assets as of August 31.&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;margin-bottom:7px;margin-left:0px;margin-top:0px;margin-right:0px;"&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;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:FactorsAffectingPerfTextBlock>
    <oef:LineGraphTableTextBlock contextRef="C000235234_ClassMember" id="ixv-235">How did the Fund perform over the life of Fund?

 &#160;&#160;
CUMULATIVE PERFORMANCE
April 13, 2022 through August 31, 2025.
Initial investment of $10,000.
Fidelity&#xae; Sustainable Low Duration Bond Fund


$10,000

$10,001


$10,404


$11,006



Bloomberg US Treasury Bill: 6-9 Months Index


$10,000

$9,990


$10,301


$10,854



Bloomberg U.S. Aggregate Bond Index


$10,000

$9,696


$9,581


$10,280



&#160;

2022

2023

2024

2025









&#160;
</oef:LineGraphTableTextBlock>
    <oef:LineGraphAndTableMeasureName contextRef="C000235234_LG_ClassMember_4YR" id="ixv-254">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity&#xae; Sustainable Low Duration Bond Fund&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000235234_ClassMember_AsOf_2022"
      decimals="0"
      id="ixv-224571"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235234_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-224572"
      unitRef="usd">10001</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235234_ClassMember_AsOf_2024"
      decimals="0"
      id="ixv-224573"
      unitRef="usd">10404</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235234_ClassMember_AsOf_2025"
      decimals="0"
      id="ixv-224574"
      unitRef="usd">11006</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000235234_LG_1_AdditionalIndexMember_4YR"
      id="ixv-275">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg US Treasury Bill: 6-9 Months Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000235234_1_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-224575"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235234_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-224576"
      unitRef="usd">9990</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235234_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-224577"
      unitRef="usd">10301</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235234_1_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-224578"
      unitRef="usd">10854</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000235234_LG_2_AdditionalIndexMember_4YR"
      id="ixv-296">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg U.S. Aggregate Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000235234_2_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-224579"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235234_2_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-224580"
      unitRef="usd">9696</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235234_2_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-224581"
      unitRef="usd">9581</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235234_2_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-224582"
      unitRef="usd">10280</oef:AccmVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000235234_ClassMember" id="ixv-348">AVERAGE ANNUAL TOTAL RETURNS:

&#160;

1 Year

Life of Fund&#160;A


Fidelity&#xae; Sustainable Low Duration Bond Fund

4.81%

4.31%


Bloomberg US Treasury Bill: 6-9 Months Index

4.29%


3.73%


Bloomberg U.S. Aggregate Bond Index

3.14%


1.74%




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="C000235234_NoLoadClassMember_1YR"
      decimals="INF"
      id="ixv-224583"
      unitRef="pure">0.0481</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235234_NoLoadClassMember_2024-09-01_2025-08-31"
      decimals="INF"
      id="ixv-224584"
      unitRef="pure">0.0431</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235234_0_AdditionalIndexMember_1YR"
      decimals="INF"
      id="ixv-224585"
      unitRef="pure">0.0429</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235234_0_AdditionalIndexMember_LOC"
      decimals="INF"
      id="ixv-224586"
      unitRef="pure">0.0373</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235234_1_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-224587"
      unitRef="pure">0.0314</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235234_1_BBIndexMember_LOC"
      decimals="INF"
      id="ixv-224588"
      unitRef="pure">0.0174</oef:AvgAnnlRtrPct>
    <oef:PerfInceptionDate
      contextRef="C000235234_Perf_2022-04-13_ClassMember"
      id="ixv-403">2022-04-13</oef:PerfInceptionDate>
    <oef:UpdPerfInfoLocationTextBlock contextRef="C000235234_ClassMember" id="ixv-413">&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="C000235234_ClassMember" id="ixv-425">&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="C000235234_ClassMember" id="ixv-429">&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="C000235234_ClassMember" id="ixv-435">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;Key Fund Statistics&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(as of August 31, 2025)&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;$&lt;/span&gt;47,087,123&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;322&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;74,586&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;58&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>
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&#160;
U.S. Government and U.S. Government Agency Obligations

29.5


AAA

17.8


AA

3.8


A

24.9


BBB

19.2


BB

0.1


Not Rated

1.8


Short-Term Investments and Net Other Assets (Liabilities)

2.9




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

U.S. Government and U.S. Government Agency Obligations - 29.5


&#160;

AAA - 17.8&#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;

AA - 3.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

A - 24.9&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BBB - 19.2&#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;

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


&#160;

Not Rated - 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;

Short-Term Investments and Net Other Assets (Liabilities) - 2.9


&#160;


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




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

47.5


U.S. Treasury Obligations

29.5


Asset-Backed Securities

19.0


CMOs and Other Mortgage Related Securities

0.6


Other Investments

0.5


Short-Term Investments and Net Other Assets (Liabilities)

2.9




ASSET ALLOCATION (% of Fund's net assets)


&#160;



&#160;

Corporate Bonds - 47.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

U.S. Treasury Obligations - 29.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Asset-Backed Securities - 19.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

CMOs and Other Mortgage Related Securities - 0.6


&#160;

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


&#160;

Short-Term Investments and Net Other Assets (Liabilities) - 2.9


&#160;






United States

85.8


Canada

4.2


United Kingdom

3.7


Ireland

1.6


Netherlands

1.5


Japan

0.8


Sweden

0.4


Italy

0.4


Norway

0.4


Others

1.2




GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

United States - 85.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Canada - 4.2&#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;

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


&#160;

Ireland - 1.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Netherlands - 1.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Japan - 0.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Sweden - 0.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Italy - 0.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Norway - 0.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Others - 1.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;




&#160;




&#160;
&#160;
</oef:HoldingsTableTextBlock>
    <oef:PctOfNav
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    <oef:PctOfNav
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    <oef:PctOfNav
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      id="ixv-224603"
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    <oef:PctOfNav
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      id="ixv-224604"
      unitRef="pure">0.006</oef:PctOfNav>
    <oef:PctOfNav
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    <oef:PctOfNav
      contextRef="C000235234_GD_US_Member"
      decimals="INF"
      id="ixv-224607"
      unitRef="pure">0.858</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235234_GD_CA_Member"
      decimals="INF"
      id="ixv-224608"
      unitRef="pure">0.042</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
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      unitRef="pure">0.037</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-224610"
      unitRef="pure">0.016</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-224611"
      unitRef="pure">0.015</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235234_GD_JP_Member"
      decimals="INF"
      id="ixv-224612"
      unitRef="pure">0.008</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235234_GD_SE_Member"
      decimals="INF"
      id="ixv-224613"
      unitRef="pure">0.004</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235234_GD_IT_Member"
      decimals="INF"
      id="ixv-224614"
      unitRef="pure">0.004</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235234_GD_NO_Member"
      decimals="INF"
      id="ixv-224615"
      unitRef="pure">0.004</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235234_GD_Other_Member"
      decimals="INF"
      id="ixv-224616"
      unitRef="pure">0.012</oef:PctOfNav>
    <oef:LargestHoldingsTableTextBlock contextRef="C000235234_ClassMember" id="ixv-919">TOP HOLDINGS(% of Fund's net assets)

&#160;

&#160;


US Treasury Bill

21.6


&#160;


US Treasury Notes

7.9


&#160;


JPMorgan Chase &amp; Co

2.0


&#160;


Bank of America Corp

1.7


&#160;


Morgan Stanley

1.6


&#160;


Goldman Sachs Group Inc/The

1.3


&#160;


Wells Fargo &amp; Co

1.2


&#160;


GMF Floorplan Owner Revolving Trust

1.1


&#160;


Citibank NA

1.0


&#160;


Athene Global Funding

1.0


&#160;


&#160;

40.4

&#160;



</oef:LargestHoldingsTableTextBlock>
    <oef:PctOfNav
      contextRef="C000235234_TH_0_Member"
      decimals="INF"
      id="ixv-224617"
      unitRef="pure">0.216</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235234_TH_1_Member"
      decimals="INF"
      id="ixv-224618"
      unitRef="pure">0.079</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235234_TH_2_Member"
      decimals="INF"
      id="ixv-224619"
      unitRef="pure">0.020</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235234_TH_3_Member"
      decimals="INF"
      id="ixv-224620"
      unitRef="pure">0.017</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235234_TH_4_Member"
      decimals="INF"
      id="ixv-224621"
      unitRef="pure">0.016</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235234_TH_5_Member"
      decimals="INF"
      id="ixv-224622"
      unitRef="pure">0.013</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235234_TH_6_Member"
      decimals="INF"
      id="ixv-224623"
      unitRef="pure">0.012</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235234_TH_7_Member"
      decimals="INF"
      id="ixv-224624"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235234_TH_8_Member"
      decimals="INF"
      id="ixv-224625"
      unitRef="pure">0.010</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235234_TH_9_Member"
      decimals="INF"
      id="ixv-224626"
      unitRef="pure">0.010</oef:PctOfNav>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-1090">2025-08-31</dei:DocumentPeriodEndDate>
    <oef:FundName contextRef="C000235233_ClassMember" id="ixv-1102">Fidelity&#xae; Sustainable Low Duration Bond Fund</oef:FundName>
    <oef:ClassName contextRef="C000235233_ClassMember" id="ixv-1105">Fidelity Advisor&#xae; Sustainable Low Duration Bond Fund Class Z</oef:ClassName>
    <dei:TradingSymbol contextRef="C000235233_ClassMember" id="ixv-1109">FAPEX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000235233_ClassMember" id="ixv-1128">This annual shareholder report contains information about Fidelity&#xae; Sustainable Low Duration Bond Fund for the period September 1, 2024 to August 31, 2025.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000235233_ClassMember" id="ixv-1130">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000235233_ClassMember" id="ixv-1135">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="C000235233_ClassMember" id="ixv-1137">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000235233_ClassMember" id="ixv-1140">1-877-208-0098</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000235233_ClassMember" id="ixv-1143">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000235233_ClassMember" id="ixv-1150">&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:45%; 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:24%; 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:30%; 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 $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:45%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Class Z&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:24%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$ &lt;/span&gt;21&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:30%; 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="C000235233_ClassMember"
      decimals="0"
      id="ixv-224627"
      unitRef="usd">21</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000235233_ClassMember"
      decimals="INF"
      id="ixv-224628"
      unitRef="pure">0.0020</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000235233_ClassMember" id="ixv-1192">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What affected the Fund's performance this period?&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;U.S. taxable investment-grade bonds posted a solid advance for the 12 months ending August 31, 2025, navigating tariff-related uncertainty since late 2024 but buoyed by relatively stable consumer inflation, a resilient economy and the expectation of policy interest-rate cuts by the U.S. Federal Reserve in the second half of 2025.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Against this backdrop, the fund's strategy of holding short-term debt in high-quality corporations contributed to performance versus the all-U.S.-Treasury benchmark for the fiscal year. Within corporates, debt holdings among financial institutions, especially banks, and industrial firms, particularly in the consumer cyclical and consumer non-cyclical segments, added notable value.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Non-benchmark exposure to asset-backed securities, primarily car loan debt, also meaningfully contributed.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;In contrast, the fund's yield-curve positioning detracted from relative performance.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;A small allocation to cash was a modest drag as well.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;At period end, corporates made up about 48% of fund assets, down from roughly 60% a year ago. Exposure to U.S. Treasurys rose from about 26% to roughly 30% of assets during the fiscal year, while exposure to ABS was up from about 11% to 19% of assets as of August 31.&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;margin-bottom:7px;margin-left:0px;margin-top:0px;margin-right:0px;"&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;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:FactorsAffectingPerfTextBlock>
    <oef:LineGraphTableTextBlock contextRef="C000235233_ClassMember" id="ixv-1221">How did the Fund perform over the life of Fund?

 &#160;&#160;
CUMULATIVE PERFORMANCE
April 13, 2022 through August 31, 2025.
Initial investment of $10,000.
Class Z


$10,000

$10,003


$10,411


$11,019



Bloomberg US Treasury Bill: 6-9 Months Index


$10,000

$9,990


$10,301


$10,854



Bloomberg U.S. Aggregate Bond Index


$10,000

$9,696


$9,581


$10,280



&#160;

2022

2023

2024

2025









&#160;
</oef:LineGraphTableTextBlock>
    <oef:LineGraphAndTableMeasureName contextRef="C000235233_LG_ClassMember_4YR" id="ixv-1240">&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="C000235233_ClassMember_AsOf_2022"
      decimals="0"
      id="ixv-224629"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235233_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-224630"
      unitRef="usd">10003</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235233_ClassMember_AsOf_2024"
      decimals="0"
      id="ixv-224631"
      unitRef="usd">10411</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235233_ClassMember_AsOf_2025"
      decimals="0"
      id="ixv-224632"
      unitRef="usd">11019</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000235233_LG_1_AdditionalIndexMember_4YR"
      id="ixv-1261">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg US Treasury Bill: 6-9 Months Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000235233_1_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-224633"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235233_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-224634"
      unitRef="usd">9990</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235233_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-224635"
      unitRef="usd">10301</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235233_1_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-224636"
      unitRef="usd">10854</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000235233_LG_2_AdditionalIndexMember_4YR"
      id="ixv-1282">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg U.S. Aggregate Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000235233_2_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-224637"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235233_2_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-224638"
      unitRef="usd">9696</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235233_2_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-224639"
      unitRef="usd">9581</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235233_2_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-224640"
      unitRef="usd">10280</oef:AccmVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000235233_ClassMember" id="ixv-1334">AVERAGE ANNUAL TOTAL RETURNS:

&#160;

1 Year

Life of Fund&#160;A


Class Z

4.86%

4.36%


Bloomberg US Treasury Bill: 6-9 Months Index

4.29%


3.73%


Bloomberg U.S. Aggregate Bond Index

3.14%


1.74%




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="C000235233_NoLoadClassMember_1YR"
      decimals="INF"
      id="ixv-224641"
      unitRef="pure">0.0486</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235233_NoLoadClassMember_2024-09-01_2025-08-31"
      decimals="INF"
      id="ixv-224642"
      unitRef="pure">0.0436</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235233_0_AdditionalIndexMember_1YR"
      decimals="INF"
      id="ixv-224643"
      unitRef="pure">0.0429</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235233_0_AdditionalIndexMember_LOC"
      decimals="INF"
      id="ixv-224644"
      unitRef="pure">0.0373</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235233_1_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-224645"
      unitRef="pure">0.0314</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235233_1_BBIndexMember_LOC"
      decimals="INF"
      id="ixv-224646"
      unitRef="pure">0.0174</oef:AvgAnnlRtrPct>
    <oef:PerfInceptionDate
      contextRef="C000235233_Perf_2022-04-13_ClassMember"
      id="ixv-1389">2022-04-13</oef:PerfInceptionDate>
    <oef:UpdPerfInfoLocationTextBlock contextRef="C000235233_ClassMember" id="ixv-1399">&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="C000235233_ClassMember" id="ixv-1411">&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="C000235233_ClassMember" id="ixv-1415">&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="C000235233_ClassMember" id="ixv-1421">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;Key Fund Statistics&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(as of August 31, 2025)&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;$&lt;/span&gt;47,087,123&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;322&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;74,586&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;58&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="C000235233_InstantMember"
      decimals="0"
      id="ixv-224647"
      unitRef="usd">47087123</us-gaap:AssetsNet>
    <oef:HoldingsCount
      contextRef="C000235233_InstantMember"
      decimals="INF"
      id="ixv-224648"
      unitRef="holding">322</oef:HoldingsCount>
    <oef:AdvisoryFeesPaidAmt
      contextRef="C000235233_ClassMember"
      decimals="0"
      id="ixv-224649"
      unitRef="usd">74586</oef:AdvisoryFeesPaidAmt>
    <us-gaap:InvestmentCompanyPortfolioTurnover
      contextRef="C000235233_ClassMember"
      decimals="INF"
      id="ixv-224650"
      unitRef="pure">0.58</us-gaap:InvestmentCompanyPortfolioTurnover>
    <oef:HoldingsTableTextBlock contextRef="C000235233_ClassMember" id="ixv-1496">
&#160;
U.S. Government and U.S. Government Agency Obligations

29.5


AAA

17.8


AA

3.8


A

24.9


BBB

19.2


BB

0.1


Not Rated

1.8


Short-Term Investments and Net Other Assets (Liabilities)

2.9




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

U.S. Government and U.S. Government Agency Obligations - 29.5


&#160;

AAA - 17.8&#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;

AA - 3.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

A - 24.9&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BBB - 19.2&#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;

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


&#160;

Not Rated - 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;

Short-Term Investments and Net Other Assets (Liabilities) - 2.9


&#160;


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




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

47.5


U.S. Treasury Obligations

29.5


Asset-Backed Securities

19.0


CMOs and Other Mortgage Related Securities

0.6


Other Investments

0.5


Short-Term Investments and Net Other Assets (Liabilities)

2.9




ASSET ALLOCATION (% of Fund's net assets)


&#160;



&#160;

Corporate Bonds - 47.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

U.S. Treasury Obligations - 29.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Asset-Backed Securities - 19.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

CMOs and Other Mortgage Related Securities - 0.6


&#160;

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


&#160;

Short-Term Investments and Net Other Assets (Liabilities) - 2.9


&#160;






United States

85.8


Canada

4.2


United Kingdom

3.7


Ireland

1.6


Netherlands

1.5


Japan

0.8


Sweden

0.4


Italy

0.4


Norway

0.4


Others

1.2




GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

United States - 85.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Canada - 4.2&#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;

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


&#160;

Ireland - 1.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Netherlands - 1.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Japan - 0.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Sweden - 0.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Italy - 0.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Norway - 0.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Others - 1.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;




&#160;




&#160;
&#160;
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    <oef:LargestHoldingsTableTextBlock contextRef="C000235233_ClassMember" id="ixv-1905">TOP HOLDINGS(% of Fund's net assets)

&#160;

&#160;


US Treasury Bill

21.6


&#160;


US Treasury Notes

7.9


&#160;


JPMorgan Chase &amp; Co

2.0


&#160;


Bank of America Corp

1.7


&#160;


Morgan Stanley

1.6


&#160;


Goldman Sachs Group Inc/The

1.3


&#160;


Wells Fargo &amp; Co

1.2


&#160;


GMF Floorplan Owner Revolving Trust

1.1


&#160;


Citibank NA

1.0


&#160;


Athene Global Funding

1.0


&#160;


&#160;

40.4

&#160;



</oef:LargestHoldingsTableTextBlock>
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    <oef:PctOfNav
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      id="ixv-224676"
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      unitRef="pure">0.020</oef:PctOfNav>
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      id="ixv-224678"
      unitRef="pure">0.017</oef:PctOfNav>
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      id="ixv-224679"
      unitRef="pure">0.016</oef:PctOfNav>
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      id="ixv-224680"
      unitRef="pure">0.013</oef:PctOfNav>
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    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-2076">2025-08-31</dei:DocumentPeriodEndDate>
    <oef:FundName contextRef="C000235230_ClassMember" id="ixv-2088">Fidelity&#xae; Sustainable Low Duration Bond Fund</oef:FundName>
    <oef:ClassName contextRef="C000235230_ClassMember" id="ixv-2091">Fidelity Advisor&#xae; Sustainable Low Duration Bond Fund Class M</oef:ClassName>
    <dei:TradingSymbol contextRef="C000235230_ClassMember" id="ixv-2095">FAPBX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000235230_ClassMember" id="ixv-2114">This annual shareholder report contains information about Fidelity&#xae; Sustainable Low Duration Bond Fund for the period September 1, 2024 to August 31, 2025.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000235230_ClassMember" id="ixv-2116">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000235230_ClassMember" id="ixv-2121">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="C000235230_ClassMember" id="ixv-2123">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000235230_ClassMember" id="ixv-2126">1-877-208-0098</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000235230_ClassMember" id="ixv-2129">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000235230_ClassMember" id="ixv-2136">&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:45%; 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:24%; 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:30%; 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 $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:45%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Class M&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:24%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$ &lt;/span&gt;43&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:30%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;0.42&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="C000235230_ClassMember"
      decimals="0"
      id="ixv-224685"
      unitRef="usd">43</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000235230_ClassMember"
      decimals="INF"
      id="ixv-224686"
      unitRef="pure">0.0042</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000235230_ClassMember" id="ixv-2178">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What affected the Fund's performance this period?&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;U.S. taxable investment-grade bonds posted a solid advance for the 12 months ending August 31, 2025, navigating tariff-related uncertainty since late 2024 but buoyed by relatively stable consumer inflation, a resilient economy and the expectation of policy interest-rate cuts by the U.S. Federal Reserve in the second half of 2025.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Against this backdrop, the fund's strategy of holding short-term debt in high-quality corporations contributed to performance versus the all-U.S.-Treasury benchmark for the fiscal year. Within corporates, debt holdings among financial institutions, especially banks, and industrial firms, particularly in the consumer cyclical and consumer non-cyclical segments, added notable value.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Non-benchmark exposure to asset-backed securities, primarily car loan debt, also meaningfully contributed.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;In contrast, the fund's yield-curve positioning detracted from relative performance.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;A small allocation to cash was a modest drag as well.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;At period end, corporates made up about 48% of fund assets, down from roughly 60% a year ago. Exposure to U.S. Treasurys rose from about 26% to roughly 30% of assets during the fiscal year, while exposure to ABS was up from about 11% to 19% of assets as of August 31.&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;margin-bottom:7px;margin-left:0px;margin-top:0px;margin-right:0px;"&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;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:FactorsAffectingPerfTextBlock>
    <oef:LineGraphTableTextBlock contextRef="C000235230_ClassMember" id="ixv-2207">How did the Fund perform over the life of Fund?

 &#160;&#160;
CUMULATIVE PERFORMANCE
April 13, 2022 through August 31, 2025.
Initial investment of $10,000&#160;and the current sales charge was paid.
Class M


$9,850

$9,845


$10,224


$10,796



Bloomberg US Treasury Bill: 6-9 Months Index


$10,000

$9,990


$10,301


$10,854



Bloomberg U.S. Aggregate Bond Index


$10,000

$9,696


$9,581


$10,280



&#160;

2022

2023

2024

2025









&#160;
</oef:LineGraphTableTextBlock>
    <oef:LineGraphAndTableMeasureName contextRef="C000235230_LG_ClassMember_4YR" id="ixv-2228">&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="C000235230_ClassMember_AsOf_2022"
      decimals="0"
      id="ixv-224687"
      unitRef="usd">9850</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235230_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-224688"
      unitRef="usd">9845</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235230_ClassMember_AsOf_2024"
      decimals="0"
      id="ixv-224689"
      unitRef="usd">10224</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235230_ClassMember_AsOf_2025"
      decimals="0"
      id="ixv-224690"
      unitRef="usd">10796</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000235230_LG_1_AdditionalIndexMember_4YR"
      id="ixv-2249">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg US Treasury Bill: 6-9 Months Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000235230_1_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-224691"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235230_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-224692"
      unitRef="usd">9990</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235230_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-224693"
      unitRef="usd">10301</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235230_1_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-224694"
      unitRef="usd">10854</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000235230_LG_2_AdditionalIndexMember_4YR"
      id="ixv-2270">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg U.S. Aggregate Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000235230_2_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-224695"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235230_2_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-224696"
      unitRef="usd">9696</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235230_2_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-224697"
      unitRef="usd">9581</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235230_2_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-224698"
      unitRef="usd">10280</oef:AccmVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000235230_ClassMember" id="ixv-2322">AVERAGE ANNUAL TOTAL RETURNS:

&#160;

1 Year

Life of Fund&#160;A


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

3.06%

3.66%


Class M (without 1.50% sales charge)

4.63%

4.13%


Bloomberg US Treasury Bill: 6-9 Months Index

4.29%


3.73%


Bloomberg U.S. Aggregate Bond Index

3.14%


1.74%




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="C000235230_ClassMember_1YR"
      decimals="INF"
      id="ixv-224699"
      unitRef="pure">0.0306</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235230_ClassMember_2024-09-01_2025-08-31"
      decimals="INF"
      id="ixv-224700"
      unitRef="pure">0.0366</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235230_NoLoadClassMember_1YR"
      decimals="INF"
      id="ixv-224701"
      unitRef="pure">0.0463</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235230_NoLoadClassMember_2024-09-01_2025-08-31"
      decimals="INF"
      id="ixv-224702"
      unitRef="pure">0.0413</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
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      decimals="INF"
      id="ixv-224703"
      unitRef="pure">0.0429</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235230_0_AdditionalIndexMember_LOC"
      decimals="INF"
      id="ixv-224704"
      unitRef="pure">0.0373</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235230_1_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-224705"
      unitRef="pure">0.0314</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235230_1_BBIndexMember_LOC"
      decimals="INF"
      id="ixv-224706"
      unitRef="pure">0.0174</oef:AvgAnnlRtrPct>
    <oef:PerfInceptionDate
      contextRef="C000235230_Perf_2022-04-13_ClassMember"
      id="ixv-2388">2022-04-13</oef:PerfInceptionDate>
    <oef:UpdPerfInfoLocationTextBlock contextRef="C000235230_ClassMember" id="ixv-2398">&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="C000235230_ClassMember" id="ixv-2410">&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="C000235230_ClassMember" id="ixv-2414">&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="C000235230_ClassMember" id="ixv-2420">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;Key Fund Statistics&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(as of August 31, 2025)&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;$&lt;/span&gt;47,087,123&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;322&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;74,586&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;58&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="C000235230_InstantMember"
      decimals="0"
      id="ixv-224707"
      unitRef="usd">47087123</us-gaap:AssetsNet>
    <oef:HoldingsCount
      contextRef="C000235230_InstantMember"
      decimals="INF"
      id="ixv-224708"
      unitRef="holding">322</oef:HoldingsCount>
    <oef:AdvisoryFeesPaidAmt
      contextRef="C000235230_ClassMember"
      decimals="0"
      id="ixv-224709"
      unitRef="usd">74586</oef:AdvisoryFeesPaidAmt>
    <us-gaap:InvestmentCompanyPortfolioTurnover
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      id="ixv-224710"
      unitRef="pure">0.58</us-gaap:InvestmentCompanyPortfolioTurnover>
    <oef:HoldingsTableTextBlock contextRef="C000235230_ClassMember" id="ixv-2495">
&#160;
U.S. Government and U.S. Government Agency Obligations

29.5


AAA

17.8


AA

3.8


A

24.9


BBB

19.2


BB

0.1


Not Rated

1.8


Short-Term Investments and Net Other Assets (Liabilities)

2.9




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

U.S. Government and U.S. Government Agency Obligations - 29.5


&#160;

AAA - 17.8&#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;

AA - 3.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

A - 24.9&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BBB - 19.2&#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;

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


&#160;

Not Rated - 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;

Short-Term Investments and Net Other Assets (Liabilities) - 2.9


&#160;


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




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

47.5


U.S. Treasury Obligations

29.5


Asset-Backed Securities

19.0


CMOs and Other Mortgage Related Securities

0.6


Other Investments

0.5


Short-Term Investments and Net Other Assets (Liabilities)

2.9




ASSET ALLOCATION (% of Fund's net assets)


&#160;



&#160;

Corporate Bonds - 47.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

U.S. Treasury Obligations - 29.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Asset-Backed Securities - 19.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

CMOs and Other Mortgage Related Securities - 0.6


&#160;

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


&#160;

Short-Term Investments and Net Other Assets (Liabilities) - 2.9


&#160;






United States

85.8


Canada

4.2


United Kingdom

3.7


Ireland

1.6


Netherlands

1.5


Japan

0.8


Sweden

0.4


Italy

0.4


Norway

0.4


Others

1.2




GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

United States - 85.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Canada - 4.2&#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;

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


&#160;

Ireland - 1.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Netherlands - 1.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Japan - 0.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Sweden - 0.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Italy - 0.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Norway - 0.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Others - 1.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;




&#160;




&#160;
&#160;
</oef:HoldingsTableTextBlock>
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    <oef:PctOfNav
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      unitRef="pure">0.858</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-224726"
      unitRef="pure">0.042</oef:PctOfNav>
    <oef:PctOfNav
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      id="ixv-224728"
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    <oef:PctOfNav
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      id="ixv-224729"
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      id="ixv-224732"
      unitRef="pure">0.004</oef:PctOfNav>
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      id="ixv-224733"
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    <oef:PctOfNav
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    <oef:LargestHoldingsTableTextBlock contextRef="C000235230_ClassMember" id="ixv-2904">TOP HOLDINGS(% of Fund's net assets)

&#160;

&#160;


US Treasury Bill

21.6


&#160;


US Treasury Notes

7.9


&#160;


JPMorgan Chase &amp; Co

2.0


&#160;


Bank of America Corp

1.7


&#160;


Morgan Stanley

1.6


&#160;


Goldman Sachs Group Inc/The

1.3


&#160;


Wells Fargo &amp; Co

1.2


&#160;


GMF Floorplan Owner Revolving Trust

1.1


&#160;


Citibank NA

1.0


&#160;


Athene Global Funding

1.0


&#160;


&#160;

40.4

&#160;



</oef:LargestHoldingsTableTextBlock>
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      id="ixv-224735"
      unitRef="pure">0.216</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235230_TH_1_Member"
      decimals="INF"
      id="ixv-224736"
      unitRef="pure">0.079</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235230_TH_2_Member"
      decimals="INF"
      id="ixv-224737"
      unitRef="pure">0.020</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235230_TH_3_Member"
      decimals="INF"
      id="ixv-224738"
      unitRef="pure">0.017</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235230_TH_4_Member"
      decimals="INF"
      id="ixv-224739"
      unitRef="pure">0.016</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235230_TH_5_Member"
      decimals="INF"
      id="ixv-224740"
      unitRef="pure">0.013</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235230_TH_6_Member"
      decimals="INF"
      id="ixv-224741"
      unitRef="pure">0.012</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235230_TH_7_Member"
      decimals="INF"
      id="ixv-224742"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235230_TH_8_Member"
      decimals="INF"
      id="ixv-224743"
      unitRef="pure">0.010</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235230_TH_9_Member"
      decimals="INF"
      id="ixv-224744"
      unitRef="pure">0.010</oef:PctOfNav>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-3075">2025-08-31</dei:DocumentPeriodEndDate>
    <oef:FundName contextRef="C000235232_ClassMember" id="ixv-3087">Fidelity&#xae; Sustainable Low Duration Bond Fund</oef:FundName>
    <oef:ClassName contextRef="C000235232_ClassMember" id="ixv-3090">Fidelity Advisor&#xae; Sustainable Low Duration Bond Fund Class I</oef:ClassName>
    <dei:TradingSymbol contextRef="C000235232_ClassMember" id="ixv-3094">FAPDX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000235232_ClassMember" id="ixv-3113">This annual shareholder report contains information about Fidelity&#xae; Sustainable Low Duration Bond Fund for the period September 1, 2024 to August 31, 2025.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000235232_ClassMember" id="ixv-3115">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000235232_ClassMember" id="ixv-3120">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="C000235232_ClassMember" id="ixv-3122">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000235232_ClassMember" id="ixv-3125">1-877-208-0098</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000235232_ClassMember" id="ixv-3128">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000235232_ClassMember" id="ixv-3135">&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:45%; 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:24%; 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:30%; 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 $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:45%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Class I&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:24%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$ &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:30%; 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="C000235232_ClassMember"
      decimals="0"
      id="ixv-224745"
      unitRef="usd">26</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000235232_ClassMember"
      decimals="INF"
      id="ixv-224746"
      unitRef="pure">0.0025</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000235232_ClassMember" id="ixv-3177">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What affected the Fund's performance this period?&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;U.S. taxable investment-grade bonds posted a solid advance for the 12 months ending August 31, 2025, navigating tariff-related uncertainty since late 2024 but buoyed by relatively stable consumer inflation, a resilient economy and the expectation of policy interest-rate cuts by the U.S. Federal Reserve in the second half of 2025.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Against this backdrop, the fund's strategy of holding short-term debt in high-quality corporations contributed to performance versus the all-U.S.-Treasury benchmark for the fiscal year. Within corporates, debt holdings among financial institutions, especially banks, and industrial firms, particularly in the consumer cyclical and consumer non-cyclical segments, added notable value.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Non-benchmark exposure to asset-backed securities, primarily car loan debt, also meaningfully contributed.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;In contrast, the fund's yield-curve positioning detracted from relative performance.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;A small allocation to cash was a modest drag as well.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;At period end, corporates made up about 48% of fund assets, down from roughly 60% a year ago. Exposure to U.S. Treasurys rose from about 26% to roughly 30% of assets during the fiscal year, while exposure to ABS was up from about 11% to 19% of assets as of August 31.&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;margin-bottom:7px;margin-left:0px;margin-top:0px;margin-right:0px;"&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;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:FactorsAffectingPerfTextBlock>
    <oef:LineGraphTableTextBlock contextRef="C000235232_ClassMember" id="ixv-3206">How did the Fund perform over the life of Fund?

 &#160;&#160;
CUMULATIVE PERFORMANCE
April 13, 2022 through August 31, 2025.
Initial investment of $10,000.
Class I


$10,000

$10,001


$10,404


$11,006



Bloomberg US Treasury Bill: 6-9 Months Index


$10,000

$9,990


$10,301


$10,854



Bloomberg U.S. Aggregate Bond Index


$10,000

$9,696


$9,581


$10,280



&#160;

2022

2023

2024

2025









&#160;
</oef:LineGraphTableTextBlock>
    <oef:LineGraphAndTableMeasureName contextRef="C000235232_LG_ClassMember_4YR" id="ixv-3225">&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="C000235232_ClassMember_AsOf_2022"
      decimals="0"
      id="ixv-224747"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235232_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-224748"
      unitRef="usd">10001</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235232_ClassMember_AsOf_2024"
      decimals="0"
      id="ixv-224749"
      unitRef="usd">10404</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235232_ClassMember_AsOf_2025"
      decimals="0"
      id="ixv-224750"
      unitRef="usd">11006</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000235232_LG_1_AdditionalIndexMember_4YR"
      id="ixv-3246">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg US Treasury Bill: 6-9 Months Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000235232_1_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-224751"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235232_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-224752"
      unitRef="usd">9990</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235232_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-224753"
      unitRef="usd">10301</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235232_1_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-224754"
      unitRef="usd">10854</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000235232_LG_2_AdditionalIndexMember_4YR"
      id="ixv-3267">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg U.S. Aggregate Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000235232_2_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-224755"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235232_2_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-224756"
      unitRef="usd">9696</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235232_2_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-224757"
      unitRef="usd">9581</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235232_2_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-224758"
      unitRef="usd">10280</oef:AccmVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000235232_ClassMember" id="ixv-3319">AVERAGE ANNUAL TOTAL RETURNS:

&#160;

1 Year

Life of Fund&#160;A


Class I

4.81%

4.31%


Bloomberg US Treasury Bill: 6-9 Months Index

4.29%


3.73%


Bloomberg U.S. Aggregate Bond Index

3.14%


1.74%




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="C000235232_NoLoadClassMember_1YR"
      decimals="INF"
      id="ixv-224759"
      unitRef="pure">0.0481</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235232_NoLoadClassMember_2024-09-01_2025-08-31"
      decimals="INF"
      id="ixv-224760"
      unitRef="pure">0.0431</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235232_0_AdditionalIndexMember_1YR"
      decimals="INF"
      id="ixv-224761"
      unitRef="pure">0.0429</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235232_0_AdditionalIndexMember_LOC"
      decimals="INF"
      id="ixv-224762"
      unitRef="pure">0.0373</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235232_1_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-224763"
      unitRef="pure">0.0314</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235232_1_BBIndexMember_LOC"
      decimals="INF"
      id="ixv-224764"
      unitRef="pure">0.0174</oef:AvgAnnlRtrPct>
    <oef:PerfInceptionDate
      contextRef="C000235232_Perf_2022-04-13_ClassMember"
      id="ixv-3374">2022-04-13</oef:PerfInceptionDate>
    <oef:UpdPerfInfoLocationTextBlock contextRef="C000235232_ClassMember" id="ixv-3384">&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="C000235232_ClassMember" id="ixv-3396">&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="C000235232_ClassMember" id="ixv-3400">&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="C000235232_ClassMember" id="ixv-3406">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;Key Fund Statistics&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(as of August 31, 2025)&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;$&lt;/span&gt;47,087,123&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;322&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;74,586&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;58&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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    <oef:HoldingsTableTextBlock contextRef="C000235232_ClassMember" id="ixv-3481">
&#160;
U.S. Government and U.S. Government Agency Obligations

29.5


AAA

17.8


AA

3.8


A

24.9


BBB

19.2


BB

0.1


Not Rated

1.8


Short-Term Investments and Net Other Assets (Liabilities)

2.9




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

U.S. Government and U.S. Government Agency Obligations - 29.5


&#160;

AAA - 17.8&#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;

AA - 3.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

A - 24.9&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BBB - 19.2&#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;

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


&#160;

Not Rated - 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;

Short-Term Investments and Net Other Assets (Liabilities) - 2.9


&#160;


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




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

47.5


U.S. Treasury Obligations

29.5


Asset-Backed Securities

19.0


CMOs and Other Mortgage Related Securities

0.6


Other Investments

0.5


Short-Term Investments and Net Other Assets (Liabilities)

2.9




ASSET ALLOCATION (% of Fund's net assets)


&#160;



&#160;

Corporate Bonds - 47.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

U.S. Treasury Obligations - 29.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Asset-Backed Securities - 19.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

CMOs and Other Mortgage Related Securities - 0.6


&#160;

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


&#160;

Short-Term Investments and Net Other Assets (Liabilities) - 2.9


&#160;






United States

85.8


Canada

4.2


United Kingdom

3.7


Ireland

1.6


Netherlands

1.5


Japan

0.8


Sweden

0.4


Italy

0.4


Norway

0.4


Others

1.2




GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

United States - 85.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Canada - 4.2&#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;

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


&#160;

Ireland - 1.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Netherlands - 1.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Japan - 0.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Sweden - 0.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Italy - 0.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Norway - 0.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Others - 1.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;




&#160;




&#160;
&#160;
</oef:HoldingsTableTextBlock>
    <oef:PctOfNav
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    <oef:PctOfNav
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    <oef:PctOfNav
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      decimals="INF"
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    <oef:PctOfNav
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      id="ixv-224777"
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    <oef:PctOfNav
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    <oef:PctOfNav
      contextRef="C000235232_AA_AssetBackedSecurities_Member"
      decimals="INF"
      id="ixv-224779"
      unitRef="pure">0.190</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-224780"
      unitRef="pure">0.006</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235232_AA_OtherInvestments_Member"
      decimals="INF"
      id="ixv-224781"
      unitRef="pure">0.005</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-224782"
      unitRef="pure">0.029</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235232_GD_US_Member"
      decimals="INF"
      id="ixv-224783"
      unitRef="pure">0.858</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235232_GD_CA_Member"
      decimals="INF"
      id="ixv-224784"
      unitRef="pure">0.042</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235232_GD_GB_Member"
      decimals="INF"
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      unitRef="pure">0.037</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-224786"
      unitRef="pure">0.016</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235232_GD_NL_Member"
      decimals="INF"
      id="ixv-224787"
      unitRef="pure">0.015</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235232_GD_JP_Member"
      decimals="INF"
      id="ixv-224788"
      unitRef="pure">0.008</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235232_GD_SE_Member"
      decimals="INF"
      id="ixv-224789"
      unitRef="pure">0.004</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235232_GD_IT_Member"
      decimals="INF"
      id="ixv-224790"
      unitRef="pure">0.004</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235232_GD_NO_Member"
      decimals="INF"
      id="ixv-224791"
      unitRef="pure">0.004</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235232_GD_Other_Member"
      decimals="INF"
      id="ixv-224792"
      unitRef="pure">0.012</oef:PctOfNav>
    <oef:LargestHoldingsTableTextBlock contextRef="C000235232_ClassMember" id="ixv-3890">TOP HOLDINGS(% of Fund's net assets)

&#160;

&#160;


US Treasury Bill

21.6


&#160;


US Treasury Notes

7.9


&#160;


JPMorgan Chase &amp; Co

2.0


&#160;


Bank of America Corp

1.7


&#160;


Morgan Stanley

1.6


&#160;


Goldman Sachs Group Inc/The

1.3


&#160;


Wells Fargo &amp; Co

1.2


&#160;


GMF Floorplan Owner Revolving Trust

1.1


&#160;


Citibank NA

1.0


&#160;


Athene Global Funding

1.0


&#160;


&#160;

40.4

&#160;



</oef:LargestHoldingsTableTextBlock>
    <oef:PctOfNav
      contextRef="C000235232_TH_0_Member"
      decimals="INF"
      id="ixv-224793"
      unitRef="pure">0.216</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235232_TH_1_Member"
      decimals="INF"
      id="ixv-224794"
      unitRef="pure">0.079</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235232_TH_2_Member"
      decimals="INF"
      id="ixv-224795"
      unitRef="pure">0.020</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235232_TH_3_Member"
      decimals="INF"
      id="ixv-224796"
      unitRef="pure">0.017</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235232_TH_4_Member"
      decimals="INF"
      id="ixv-224797"
      unitRef="pure">0.016</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235232_TH_5_Member"
      decimals="INF"
      id="ixv-224798"
      unitRef="pure">0.013</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235232_TH_6_Member"
      decimals="INF"
      id="ixv-224799"
      unitRef="pure">0.012</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235232_TH_7_Member"
      decimals="INF"
      id="ixv-224800"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235232_TH_8_Member"
      decimals="INF"
      id="ixv-224801"
      unitRef="pure">0.010</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235232_TH_9_Member"
      decimals="INF"
      id="ixv-224802"
      unitRef="pure">0.010</oef:PctOfNav>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-4061">2025-08-31</dei:DocumentPeriodEndDate>
    <oef:FundName contextRef="C000235231_ClassMember" id="ixv-4073">Fidelity&#xae; Sustainable Low Duration Bond Fund</oef:FundName>
    <oef:ClassName contextRef="C000235231_ClassMember" id="ixv-4076">Fidelity Advisor&#xae; Sustainable Low Duration Bond Fund Class C</oef:ClassName>
    <dei:TradingSymbol contextRef="C000235231_ClassMember" id="ixv-4080">FANDX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000235231_ClassMember" id="ixv-4099">This annual shareholder report contains information about Fidelity&#xae; Sustainable Low Duration Bond Fund for the period September 1, 2024 to August 31, 2025.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000235231_ClassMember" id="ixv-4101">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000235231_ClassMember" id="ixv-4106">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="C000235231_ClassMember" id="ixv-4108">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000235231_ClassMember" id="ixv-4111">1-877-208-0098</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000235231_ClassMember" id="ixv-4114">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000235231_ClassMember" id="ixv-4121">&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:45%; 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:24%; 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:30%; 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 $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:45%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Class C&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:24%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$ &lt;/span&gt;130&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:30%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;1.28&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;/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="C000235231_ClassMember"
      decimals="0"
      id="ixv-224803"
      unitRef="usd">130</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000235231_ClassMember"
      decimals="INF"
      id="ixv-224804"
      unitRef="pure">0.0128</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000235231_ClassMember" id="ixv-4163">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What affected the Fund's performance this period?&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;U.S. taxable investment-grade bonds posted a solid advance for the 12 months ending August 31, 2025, navigating tariff-related uncertainty since late 2024 but buoyed by relatively stable consumer inflation, a resilient economy and the expectation of policy interest-rate cuts by the U.S. Federal Reserve in the second half of 2025.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Against this backdrop, the fund's strategy of holding short-term debt in high-quality corporations contributed to performance versus the all-U.S.-Treasury benchmark for the fiscal year. Within corporates, debt holdings among financial institutions, especially banks, and industrial firms, particularly in the consumer cyclical and consumer non-cyclical segments, added notable value.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Non-benchmark exposure to asset-backed securities, primarily car loan debt, also meaningfully contributed.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;In contrast, the fund's yield-curve positioning detracted from relative performance.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;A small allocation to cash was a modest drag as well.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;At period end, corporates made up about 48% of fund assets, down from roughly 60% a year ago. Exposure to U.S. Treasurys rose from about 26% to roughly 30% of assets during the fiscal year, while exposure to ABS was up from about 11% to 19% of assets as of August 31.&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;margin-bottom:7px;margin-left:0px;margin-top:0px;margin-right:0px;"&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;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:FactorsAffectingPerfTextBlock>
    <oef:LineGraphTableTextBlock contextRef="C000235231_ClassMember" id="ixv-4192">How did the Fund perform over the life of Fund?

 &#160;&#160;
CUMULATIVE PERFORMANCE
April 13, 2022 through August 31, 2025.
Initial investment of $10,000.
Class C


$10,000

$9,957


$10,253


$10,735



Bloomberg US Treasury Bill: 6-9 Months Index


$10,000

$9,990


$10,301


$10,854



Bloomberg U.S. Aggregate Bond Index


$10,000

$9,696


$9,581


$10,280



&#160;

2022

2023

2024

2025









&#160;
</oef:LineGraphTableTextBlock>
    <oef:LineGraphAndTableMeasureName contextRef="C000235231_LG_ClassMember_4YR" id="ixv-4211">&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="C000235231_ClassMember_AsOf_2022"
      decimals="0"
      id="ixv-224805"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235231_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-224806"
      unitRef="usd">9957</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235231_ClassMember_AsOf_2024"
      decimals="0"
      id="ixv-224807"
      unitRef="usd">10253</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235231_ClassMember_AsOf_2025"
      decimals="0"
      id="ixv-224808"
      unitRef="usd">10735</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000235231_LG_1_AdditionalIndexMember_4YR"
      id="ixv-4232">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg US Treasury Bill: 6-9 Months Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000235231_1_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-224809"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235231_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-224810"
      unitRef="usd">9990</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235231_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-224811"
      unitRef="usd">10301</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235231_1_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-224812"
      unitRef="usd">10854</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000235231_LG_2_AdditionalIndexMember_4YR"
      id="ixv-4253">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg U.S. Aggregate Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000235231_2_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-224813"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235231_2_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-224814"
      unitRef="usd">9696</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235231_2_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-224815"
      unitRef="usd">9581</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235231_2_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-224816"
      unitRef="usd">10280</oef:AccmVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000235231_ClassMember" id="ixv-4305">AVERAGE ANNUAL TOTAL RETURNS:

&#160;

1 Year

Life of Fund&#160;A


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

2.74%

3.23%


Class C

3.74%

3.23%


Bloomberg US Treasury Bill: 6-9 Months Index

4.29%


3.73%


Bloomberg U.S. Aggregate Bond Index

3.14%


1.74%




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="C000235231_ClassMember_1YR"
      decimals="INF"
      id="ixv-224817"
      unitRef="pure">0.0274</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235231_ClassMember_2024-09-01_2025-08-31"
      decimals="INF"
      id="ixv-224818"
      unitRef="pure">0.0323</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235231_NoLoadClassMember_1YR"
      decimals="INF"
      id="ixv-224819"
      unitRef="pure">0.0374</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235231_NoLoadClassMember_2024-09-01_2025-08-31"
      decimals="INF"
      id="ixv-224820"
      unitRef="pure">0.0323</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235231_0_AdditionalIndexMember_1YR"
      decimals="INF"
      id="ixv-224821"
      unitRef="pure">0.0429</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235231_0_AdditionalIndexMember_LOC"
      decimals="INF"
      id="ixv-224822"
      unitRef="pure">0.0373</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235231_1_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-224823"
      unitRef="pure">0.0314</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235231_1_BBIndexMember_LOC"
      decimals="INF"
      id="ixv-224824"
      unitRef="pure">0.0174</oef:AvgAnnlRtrPct>
    <oef:PerfInceptionDate
      contextRef="C000235231_Perf_2022-04-13_ClassMember"
      id="ixv-4372">2022-04-13</oef:PerfInceptionDate>
    <oef:UpdPerfInfoLocationTextBlock contextRef="C000235231_ClassMember" id="ixv-4382">&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="C000235231_ClassMember" id="ixv-4394">&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="C000235231_ClassMember" id="ixv-4398">&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="C000235231_ClassMember" id="ixv-4404">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;Key Fund Statistics&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(as of August 31, 2025)&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;$&lt;/span&gt;47,087,123&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;322&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;74,586&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;58&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="C000235231_InstantMember"
      decimals="0"
      id="ixv-224825"
      unitRef="usd">47087123</us-gaap:AssetsNet>
    <oef:HoldingsCount
      contextRef="C000235231_InstantMember"
      decimals="INF"
      id="ixv-224826"
      unitRef="holding">322</oef:HoldingsCount>
    <oef:AdvisoryFeesPaidAmt
      contextRef="C000235231_ClassMember"
      decimals="0"
      id="ixv-224827"
      unitRef="usd">74586</oef:AdvisoryFeesPaidAmt>
    <us-gaap:InvestmentCompanyPortfolioTurnover
      contextRef="C000235231_ClassMember"
      decimals="INF"
      id="ixv-224828"
      unitRef="pure">0.58</us-gaap:InvestmentCompanyPortfolioTurnover>
    <oef:HoldingsTableTextBlock contextRef="C000235231_ClassMember" id="ixv-4479">
&#160;
U.S. Government and U.S. Government Agency Obligations

29.5


AAA

17.8


AA

3.8


A

24.9


BBB

19.2


BB

0.1


Not Rated

1.8


Short-Term Investments and Net Other Assets (Liabilities)

2.9




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

U.S. Government and U.S. Government Agency Obligations - 29.5


&#160;

AAA - 17.8&#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;

AA - 3.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

A - 24.9&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BBB - 19.2&#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;

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


&#160;

Not Rated - 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;

Short-Term Investments and Net Other Assets (Liabilities) - 2.9


&#160;


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




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

47.5


U.S. Treasury Obligations

29.5


Asset-Backed Securities

19.0


CMOs and Other Mortgage Related Securities

0.6


Other Investments

0.5


Short-Term Investments and Net Other Assets (Liabilities)

2.9




ASSET ALLOCATION (% of Fund's net assets)


&#160;



&#160;

Corporate Bonds - 47.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

U.S. Treasury Obligations - 29.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Asset-Backed Securities - 19.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

CMOs and Other Mortgage Related Securities - 0.6


&#160;

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


&#160;

Short-Term Investments and Net Other Assets (Liabilities) - 2.9


&#160;






United States

85.8


Canada

4.2


United Kingdom

3.7


Ireland

1.6


Netherlands

1.5


Japan

0.8


Sweden

0.4


Italy

0.4


Norway

0.4


Others

1.2




GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

United States - 85.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Canada - 4.2&#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;

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


&#160;

Ireland - 1.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Netherlands - 1.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Japan - 0.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Sweden - 0.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Italy - 0.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Norway - 0.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Others - 1.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;




&#160;




&#160;
&#160;
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    <oef:LargestHoldingsTableTextBlock contextRef="C000235231_ClassMember" id="ixv-4888">TOP HOLDINGS(% of Fund's net assets)

&#160;

&#160;


US Treasury Bill

21.6


&#160;


US Treasury Notes

7.9


&#160;


JPMorgan Chase &amp; Co

2.0


&#160;


Bank of America Corp

1.7


&#160;


Morgan Stanley

1.6


&#160;


Goldman Sachs Group Inc/The

1.3


&#160;


Wells Fargo &amp; Co

1.2


&#160;


GMF Floorplan Owner Revolving Trust

1.1


&#160;


Citibank NA

1.0


&#160;


Athene Global Funding

1.0


&#160;


&#160;

40.4

&#160;



</oef:LargestHoldingsTableTextBlock>
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    <oef:PctOfNav
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      unitRef="pure">0.020</oef:PctOfNav>
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      id="ixv-224856"
      unitRef="pure">0.017</oef:PctOfNav>
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      id="ixv-224857"
      unitRef="pure">0.016</oef:PctOfNav>
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      unitRef="pure">0.013</oef:PctOfNav>
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    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-5059">2025-08-31</dei:DocumentPeriodEndDate>
    <oef:FundName contextRef="C000235229_ClassMember" id="ixv-5071">Fidelity&#xae; Sustainable Low Duration Bond Fund</oef:FundName>
    <oef:ClassName contextRef="C000235229_ClassMember" id="ixv-5074">Fidelity Advisor&#xae; Sustainable Low Duration Bond Fund Class A</oef:ClassName>
    <dei:TradingSymbol contextRef="C000235229_ClassMember" id="ixv-5078">FAMZX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000235229_ClassMember" id="ixv-5097">This annual shareholder report contains information about Fidelity&#xae; Sustainable Low Duration Bond Fund for the period September 1, 2024 to August 31, 2025.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000235229_ClassMember" id="ixv-5099">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000235229_ClassMember" id="ixv-5104">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="C000235229_ClassMember" id="ixv-5106">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000235229_ClassMember" id="ixv-5109">1-877-208-0098</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000235229_ClassMember" id="ixv-5112">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000235229_ClassMember" id="ixv-5119">&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:45%; 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:24%; 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:30%; 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 $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:45%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Class A&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:24%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$ &lt;/span&gt;46&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:30%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;0.45&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:ExpensesTextBlock>
    <oef:ExpensesPaidAmt
      contextRef="C000235229_ClassMember"
      decimals="0"
      id="ixv-224863"
      unitRef="usd">46</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000235229_ClassMember"
      decimals="INF"
      id="ixv-224864"
      unitRef="pure">0.0045</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000235229_ClassMember" id="ixv-5161">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What affected the Fund's performance this period?&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;U.S. taxable investment-grade bonds posted a solid advance for the 12 months ending August 31, 2025, navigating tariff-related uncertainty since late 2024 but buoyed by relatively stable consumer inflation, a resilient economy and the expectation of policy interest-rate cuts by the U.S. Federal Reserve in the second half of 2025.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Against this backdrop, the fund's strategy of holding short-term debt in high-quality corporations contributed to performance versus the all-U.S.-Treasury benchmark for the fiscal year. Within corporates, debt holdings among financial institutions, especially banks, and industrial firms, particularly in the consumer cyclical and consumer non-cyclical segments, added notable value.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Non-benchmark exposure to asset-backed securities, primarily car loan debt, also meaningfully contributed.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;In contrast, the fund's yield-curve positioning detracted from relative performance.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;A small allocation to cash was a modest drag as well.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;At period end, corporates made up about 48% of fund assets, down from roughly 60% a year ago. Exposure to U.S. Treasurys rose from about 26% to roughly 30% of assets during the fiscal year, while exposure to ABS was up from about 11% to 19% of assets as of August 31.&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;margin-bottom:7px;margin-left:0px;margin-top:0px;margin-right:0px;"&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;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:FactorsAffectingPerfTextBlock>
    <oef:LineGraphTableTextBlock contextRef="C000235229_ClassMember" id="ixv-5190">How did the Fund perform over the life of Fund?

 &#160;&#160;
CUMULATIVE PERFORMANCE
April 13, 2022 through August 31, 2025.
Initial investment of $10,000&#160;and the current sales charge was paid.
Class A


$9,850

$9,845


$10,221


$10,791



Bloomberg US Treasury Bill: 6-9 Months Index


$10,000

$9,990


$10,301


$10,854



Bloomberg U.S. Aggregate Bond Index


$10,000

$9,696


$9,581


$10,280



&#160;

2022

2023

2024

2025









&#160;
</oef:LineGraphTableTextBlock>
    <oef:LineGraphAndTableMeasureName contextRef="C000235229_LG_ClassMember_4YR" id="ixv-5211">&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="C000235229_ClassMember_AsOf_2022"
      decimals="0"
      id="ixv-224865"
      unitRef="usd">9850</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235229_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-224866"
      unitRef="usd">9845</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235229_ClassMember_AsOf_2024"
      decimals="0"
      id="ixv-224867"
      unitRef="usd">10221</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235229_ClassMember_AsOf_2025"
      decimals="0"
      id="ixv-224868"
      unitRef="usd">10791</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000235229_LG_1_AdditionalIndexMember_4YR"
      id="ixv-5232">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg US Treasury Bill: 6-9 Months Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000235229_1_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-224869"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235229_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-224870"
      unitRef="usd">9990</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235229_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-224871"
      unitRef="usd">10301</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235229_1_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-224872"
      unitRef="usd">10854</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000235229_LG_2_AdditionalIndexMember_4YR"
      id="ixv-5253">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg U.S. Aggregate Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000235229_2_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-224873"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235229_2_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-224874"
      unitRef="usd">9696</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235229_2_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-224875"
      unitRef="usd">9581</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235229_2_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-224876"
      unitRef="usd">10280</oef:AccmVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000235229_ClassMember" id="ixv-5305">AVERAGE ANNUAL TOTAL RETURNS:

&#160;

1 Year

Life of Fund&#160;A


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

3.03%

3.64%


Class A (without 1.50% sales charge)

4.60%

4.11%


Bloomberg US Treasury Bill: 6-9 Months Index

4.29%


3.73%


Bloomberg U.S. Aggregate Bond Index

3.14%


1.74%




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="C000235229_ClassMember_1YR"
      decimals="INF"
      id="ixv-224877"
      unitRef="pure">0.0303</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235229_ClassMember_2024-09-01_2025-08-31"
      decimals="INF"
      id="ixv-224878"
      unitRef="pure">0.0364</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235229_NoLoadClassMember_1YR"
      decimals="INF"
      id="ixv-224879"
      unitRef="pure">0.0460</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235229_NoLoadClassMember_2024-09-01_2025-08-31"
      decimals="INF"
      id="ixv-224880"
      unitRef="pure">0.0411</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235229_0_AdditionalIndexMember_1YR"
      decimals="INF"
      id="ixv-224881"
      unitRef="pure">0.0429</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235229_0_AdditionalIndexMember_LOC"
      decimals="INF"
      id="ixv-224882"
      unitRef="pure">0.0373</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235229_1_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-224883"
      unitRef="pure">0.0314</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235229_1_BBIndexMember_LOC"
      decimals="INF"
      id="ixv-224884"
      unitRef="pure">0.0174</oef:AvgAnnlRtrPct>
    <oef:PerfInceptionDate
      contextRef="C000235229_Perf_2022-04-13_ClassMember"
      id="ixv-5371">2022-04-13</oef:PerfInceptionDate>
    <oef:UpdPerfInfoLocationTextBlock contextRef="C000235229_ClassMember" id="ixv-5381">&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="C000235229_ClassMember" id="ixv-5393">&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="C000235229_ClassMember" id="ixv-5397">&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="C000235229_ClassMember" id="ixv-5403">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;Key Fund Statistics&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(as of August 31, 2025)&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;$&lt;/span&gt;47,087,123&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;322&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;74,586&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;58&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="C000235229_InstantMember"
      decimals="0"
      id="ixv-224885"
      unitRef="usd">47087123</us-gaap:AssetsNet>
    <oef:HoldingsCount
      contextRef="C000235229_InstantMember"
      decimals="INF"
      id="ixv-224886"
      unitRef="holding">322</oef:HoldingsCount>
    <oef:AdvisoryFeesPaidAmt
      contextRef="C000235229_ClassMember"
      decimals="0"
      id="ixv-224887"
      unitRef="usd">74586</oef:AdvisoryFeesPaidAmt>
    <us-gaap:InvestmentCompanyPortfolioTurnover
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      decimals="INF"
      id="ixv-224888"
      unitRef="pure">0.58</us-gaap:InvestmentCompanyPortfolioTurnover>
    <oef:HoldingsTableTextBlock contextRef="C000235229_ClassMember" id="ixv-5478">
&#160;
U.S. Government and U.S. Government Agency Obligations

29.5


AAA

17.8


AA

3.8


A

24.9


BBB

19.2


BB

0.1


Not Rated

1.8


Short-Term Investments and Net Other Assets (Liabilities)

2.9




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

U.S. Government and U.S. Government Agency Obligations - 29.5


&#160;

AAA - 17.8&#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;

AA - 3.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

A - 24.9&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BBB - 19.2&#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;

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


&#160;

Not Rated - 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;

Short-Term Investments and Net Other Assets (Liabilities) - 2.9


&#160;


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




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

47.5


U.S. Treasury Obligations

29.5


Asset-Backed Securities

19.0


CMOs and Other Mortgage Related Securities

0.6


Other Investments

0.5


Short-Term Investments and Net Other Assets (Liabilities)

2.9




ASSET ALLOCATION (% of Fund's net assets)


&#160;



&#160;

Corporate Bonds - 47.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

U.S. Treasury Obligations - 29.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Asset-Backed Securities - 19.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

CMOs and Other Mortgage Related Securities - 0.6


&#160;

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


&#160;

Short-Term Investments and Net Other Assets (Liabilities) - 2.9


&#160;






United States

85.8


Canada

4.2


United Kingdom

3.7


Ireland

1.6


Netherlands

1.5


Japan

0.8


Sweden

0.4


Italy

0.4


Norway

0.4


Others

1.2




GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

United States - 85.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Canada - 4.2&#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;

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


&#160;

Ireland - 1.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Netherlands - 1.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Japan - 0.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Sweden - 0.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Italy - 0.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Norway - 0.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Others - 1.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;




&#160;




&#160;
&#160;
</oef:HoldingsTableTextBlock>
    <oef:PctOfNav
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      id="ixv-224889"
      unitRef="pure">0.295</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235229_QD_AAA_Member"
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    <oef:PctOfNav
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    <oef:PctOfNav
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      unitRef="pure">0.249</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235229_QD_BBB_Member"
      decimals="INF"
      id="ixv-224893"
      unitRef="pure">0.192</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235229_QD_BB_Member"
      decimals="INF"
      id="ixv-224894"
      unitRef="pure">0.001</oef:PctOfNav>
    <oef:PctOfNav
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      id="ixv-224895"
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    <oef:PctOfNav
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    <oef:PctOfNav
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      id="ixv-224898"
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    <oef:PctOfNav
      contextRef="C000235229_AA_AssetBackedSecurities_Member"
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      id="ixv-224899"
      unitRef="pure">0.190</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235229_AA_CMOsandOtherMortgageRelatedSecurities_Member"
      decimals="INF"
      id="ixv-224900"
      unitRef="pure">0.006</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235229_AA_OtherInvestments_Member"
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      id="ixv-224901"
      unitRef="pure">0.005</oef:PctOfNav>
    <oef:PctOfNav
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      id="ixv-224902"
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    <oef:PctOfNav
      contextRef="C000235229_GD_US_Member"
      decimals="INF"
      id="ixv-224903"
      unitRef="pure">0.858</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235229_GD_CA_Member"
      decimals="INF"
      id="ixv-224904"
      unitRef="pure">0.042</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235229_GD_GB_Member"
      decimals="INF"
      id="ixv-224905"
      unitRef="pure">0.037</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235229_GD_IE_Member"
      decimals="INF"
      id="ixv-224906"
      unitRef="pure">0.016</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235229_GD_NL_Member"
      decimals="INF"
      id="ixv-224907"
      unitRef="pure">0.015</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235229_GD_JP_Member"
      decimals="INF"
      id="ixv-224908"
      unitRef="pure">0.008</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235229_GD_SE_Member"
      decimals="INF"
      id="ixv-224909"
      unitRef="pure">0.004</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235229_GD_IT_Member"
      decimals="INF"
      id="ixv-224910"
      unitRef="pure">0.004</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235229_GD_NO_Member"
      decimals="INF"
      id="ixv-224911"
      unitRef="pure">0.004</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235229_GD_Other_Member"
      decimals="INF"
      id="ixv-224912"
      unitRef="pure">0.012</oef:PctOfNav>
    <oef:LargestHoldingsTableTextBlock contextRef="C000235229_ClassMember" id="ixv-5887">TOP HOLDINGS(% of Fund's net assets)

&#160;

&#160;


US Treasury Bill

21.6


&#160;


US Treasury Notes

7.9


&#160;


JPMorgan Chase &amp; Co

2.0


&#160;


Bank of America Corp

1.7


&#160;


Morgan Stanley

1.6


&#160;


Goldman Sachs Group Inc/The

1.3


&#160;


Wells Fargo &amp; Co

1.2


&#160;


GMF Floorplan Owner Revolving Trust

1.1


&#160;


Citibank NA

1.0


&#160;


Athene Global Funding

1.0


&#160;


&#160;

40.4

&#160;



</oef:LargestHoldingsTableTextBlock>
    <oef:PctOfNav
      contextRef="C000235229_TH_0_Member"
      decimals="INF"
      id="ixv-224913"
      unitRef="pure">0.216</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235229_TH_1_Member"
      decimals="INF"
      id="ixv-224914"
      unitRef="pure">0.079</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235229_TH_2_Member"
      decimals="INF"
      id="ixv-224915"
      unitRef="pure">0.020</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235229_TH_3_Member"
      decimals="INF"
      id="ixv-224916"
      unitRef="pure">0.017</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235229_TH_4_Member"
      decimals="INF"
      id="ixv-224917"
      unitRef="pure">0.016</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235229_TH_5_Member"
      decimals="INF"
      id="ixv-224918"
      unitRef="pure">0.013</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235229_TH_6_Member"
      decimals="INF"
      id="ixv-224919"
      unitRef="pure">0.012</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235229_TH_7_Member"
      decimals="INF"
      id="ixv-224920"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235229_TH_8_Member"
      decimals="INF"
      id="ixv-224921"
      unitRef="pure">0.010</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235229_TH_9_Member"
      decimals="INF"
      id="ixv-224922"
      unitRef="pure">0.010</oef:PctOfNav>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-6058">2025-08-31</dei:DocumentPeriodEndDate>
    <oef:FundName contextRef="C000235217_ClassMember" id="ixv-6070">Fidelity&#xae; Sustainable Core Plus Bond Fund</oef:FundName>
    <oef:ClassName contextRef="C000235217_ClassMember" id="ixv-6073">Fidelity&#xae; Sustainable Core Plus Bond Fund</oef:ClassName>
    <dei:TradingSymbol contextRef="C000235217_ClassMember" id="ixv-6077">FIAEX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000235217_ClassMember" id="ixv-6096">This annual shareholder report contains information about Fidelity&#xae; Sustainable Core Plus Bond Fund for the period September 1, 2024 to August 31, 2025.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000235217_ClassMember" id="ixv-6098">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000235217_ClassMember" id="ixv-6103">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="C000235217_ClassMember" id="ixv-6105">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000235217_ClassMember" id="ixv-6108">1-800-544-8544</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000235217_ClassMember" id="ixv-6111">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000235217_ClassMember" id="ixv-6118">&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:45%; 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:24%; 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:30%; 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 $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:45%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity&#xae; Sustainable Core Plus Bond Fund&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:24%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$ &lt;/span&gt;46&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:30%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;0.45&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:ExpensesTextBlock>
    <oef:ExpensesPaidAmt
      contextRef="C000235217_ClassMember"
      decimals="0"
      id="ixv-224923"
      unitRef="usd">46</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000235217_ClassMember"
      decimals="INF"
      id="ixv-224924"
      unitRef="pure">0.0045</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000235217_ClassMember" id="ixv-6160">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What affected the Fund's performance this period?&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;U.S. taxable investment-grade bonds posted a solid advance for the 12 months ending August 31, 2025, navigating tariff-related uncertainty since late 2024 but buoyed by relatively stable consumer inflation, a resilient economy and the expectation of policy interest-rate cuts by the U.S. Federal Reserve in the second half of 2025.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Against this backdrop, an allocation to high-yield bonds contributed to the fund's outperformance of the Bloomberg U.S. Aggregate Bond Index for the fiscal year.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Security selection also added value. Specifically, fund holdings in the corporate segment made a notable contribution to relative performance, led by picks among financials, particularly REITs and banks.&#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 and picks among collateralized loan obligations also helped.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;The fund's underweights in mortgage-backed securities and U.S. Treasurys buoyed relative performance as well.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;The portfolio's yield-curve positioning also provided a boost to performance versus the benchmark.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;In contrast, the fund's underweight in the bonds of industrial firms within the corporate sector detracted versus the benchmark.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;The fund's modestly longer duration relative to the benchmark 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;Notable changes over the past 12 months included management's decision to gradually lower the fund's overall risk profile by reducing exposure to investment-grade corporate bonds and increasing the allocation to U.S. Treasurys.&lt;/span&gt;&lt;/div&gt;
&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:italic;font-weight:normal;"&gt;Application of FMR's environmental, social, and governance (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;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:FactorsAffectingPerfTextBlock>
    <oef:LineGraphTableTextBlock contextRef="C000235217_ClassMember" id="ixv-6197">How did the Fund perform over the life of Fund?

 &#160;&#160;
CUMULATIVE PERFORMANCE
April 13, 2022 through August 31, 2025.
Initial investment of $10,000.
Fidelity&#xae; Sustainable Core Plus Bond Fund


$10,000

$9,592


$9,547


$10,275



Bloomberg MSCI U.S. Aggregate ESG Choice Bond Index


$10,000

$9,702


$9,590


$10,286



Bloomberg U.S. Aggregate Bond Index


$10,000

$9,696


$9,581


$10,280



&#160;

2022

2023

2024

2025









&#160;
</oef:LineGraphTableTextBlock>
    <oef:LineGraphAndTableMeasureName contextRef="C000235217_LG_ClassMember_4YR" id="ixv-6216">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity&#xae; Sustainable Core Plus Bond Fund&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000235217_ClassMember_AsOf_2022"
      decimals="0"
      id="ixv-224925"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235217_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-224926"
      unitRef="usd">9592</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235217_ClassMember_AsOf_2024"
      decimals="0"
      id="ixv-224927"
      unitRef="usd">9547</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235217_ClassMember_AsOf_2025"
      decimals="0"
      id="ixv-224928"
      unitRef="usd">10275</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000235217_LG_1_AdditionalIndexMember_4YR"
      id="ixv-6237">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg MSCI U.S. Aggregate ESG Choice Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000235217_1_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-224929"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235217_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-224930"
      unitRef="usd">9702</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235217_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-224931"
      unitRef="usd">9590</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235217_1_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-224932"
      unitRef="usd">10286</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000235217_LG_2_AdditionalIndexMember_4YR"
      id="ixv-6258">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg U.S. Aggregate Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000235217_2_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-224933"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235217_2_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-224934"
      unitRef="usd">9696</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235217_2_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-224935"
      unitRef="usd">9581</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235217_2_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-224936"
      unitRef="usd">10280</oef:AccmVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000235217_ClassMember" id="ixv-6310">AVERAGE ANNUAL TOTAL RETURNS:

&#160;

1 Year

Life of Fund&#160;A


Fidelity&#xae; Sustainable Core Plus Bond Fund

3.60%

1.86%


Bloomberg MSCI U.S. Aggregate ESG Choice Bond Index

3.17%


1.77%


Bloomberg U.S. Aggregate Bond Index

3.14%


1.74%




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="C000235217_NoLoadClassMember_1YR"
      decimals="INF"
      id="ixv-224937"
      unitRef="pure">0.0360</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235217_NoLoadClassMember_2024-09-01_2025-08-31"
      decimals="INF"
      id="ixv-224938"
      unitRef="pure">0.0186</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235217_0_AdditionalIndexMember_1YR"
      decimals="INF"
      id="ixv-224939"
      unitRef="pure">0.0317</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235217_0_AdditionalIndexMember_LOC"
      decimals="INF"
      id="ixv-224940"
      unitRef="pure">0.0177</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235217_1_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-224941"
      unitRef="pure">0.0314</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235217_1_BBIndexMember_LOC"
      decimals="INF"
      id="ixv-224942"
      unitRef="pure">0.0174</oef:AvgAnnlRtrPct>
    <oef:PerfInceptionDate
      contextRef="C000235217_Perf_2022-04-13_ClassMember"
      id="ixv-6365">2022-04-13</oef:PerfInceptionDate>
    <oef:UpdPerfInfoLocationTextBlock contextRef="C000235217_ClassMember" id="ixv-6375">&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="C000235217_ClassMember" id="ixv-6387">&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="C000235217_ClassMember" id="ixv-6391">&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="C000235217_ClassMember" id="ixv-6397">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;Key Fund Statistics&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(as of August 31, 2025)&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;$&lt;/span&gt;47,786,486&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;699&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;145,078&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;201&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;
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&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:AddlFundStatisticsTextBlock>
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&#160;
U.S. Government and U.S. Government Agency Obligations

55.1


AAA

5.8


AA

0.9


A

10.6


BBB

14.8


BB

4.2


B

2.5


CCC,CC,C

1.7


D

0.0


Not Rated

1.4


Equities

0.0


Short-Term Investments and Net Other Assets (Liabilities)

3.0




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

U.S. Government and U.S. Government Agency Obligations - 55.1


&#160;

AAA - 5.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

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


&#160;

A - 10.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BBB - 14.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BB - 4.2&#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;

B - 2.5&#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;


&#160;

CCC,CC,C - 1.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

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


&#160;

Not Rated - 1.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

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


&#160;

Short-Term Investments and Net Other Assets (Liabilities) - 3.0


&#160;


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




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

38.9


Corporate Bonds

33.0


U.S. Government Agency - Mortgage Securities

16.2


Asset-Backed Securities

6.0


CMOs and Other Mortgage Related Securities

0.9


Bank Loan Obligations

0.8


Foreign Government and Government Agency Obligations

0.8


Preferred Securities

0.4


Preferred Stocks

0.0


Common Stocks

0.0


Short-Term Investments and Net Other Assets (Liabilities)

3.0




ASSET ALLOCATION (% of Fund's net assets)


&#160;



&#160;

U.S. Treasury Obligations - 38.9&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Corporate Bonds - 33.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

U.S. Government Agency - Mortgage Securities - 16.2


&#160;

Asset-Backed Securities - 6.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

CMOs and Other Mortgage Related Securities - 0.9


&#160;

Bank Loan Obligations - 0.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Foreign Government and Government Agency Obligations - 0.8


&#160;

Preferred Securities - 0.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

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


&#160;

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


&#160;

Short-Term Investments and Net Other Assets (Liabilities) - 3.0


&#160;






United States

83.6


Grand Cayman (UK Overseas Ter)

3.9


United Kingdom

2.5


Bailiwick Of Jersey

1.6


Italy

1.4


France

0.8


Netherlands

0.7


Canada

0.7


Germany

0.6


Others

4.2




GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

United States - 83.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Grand Cayman (UK Overseas Ter) - 3.9&#160;&#160;&#160;&#160;


&#160;

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


&#160;

Bailiwick Of Jersey - 1.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Italy - 1.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

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


&#160;

Netherlands - 0.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Canada - 0.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Germany - 0.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Others - 4.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;




&#160;




&#160;
&#160;
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    <oef:LargestHoldingsTableTextBlock contextRef="C000235217_ClassMember" id="ixv-6998">TOP HOLDINGS(% of Fund's net assets)

&#160;

&#160;


US Treasury Notes

27.4


&#160;


US Treasury Bonds

11.5


&#160;


Fannie Mae Mortgage pass-thru certificates

5.0


&#160;


Ginnie Mae II Pool

4.1


&#160;


Uniform Mortgage Backed Securities

3.0


&#160;


Freddie Mac Gold Pool

2.8


&#160;


Bank of America Corp

1.1


&#160;


Symphony Clo Xxvi Ltd / Symphony Clo Xxvi LLC

1.0


&#160;


AES Corp/The

0.7


&#160;


Enel Finance International NV

0.7


&#160;


&#160;

57.3

&#160;



</oef:LargestHoldingsTableTextBlock>
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    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-7169">2025-08-31</dei:DocumentPeriodEndDate>
    <oef:FundName contextRef="C000235220_ClassMember" id="ixv-7181">Fidelity&#xae; Sustainable Core Plus Bond Fund</oef:FundName>
    <oef:ClassName contextRef="C000235220_ClassMember" id="ixv-7184">Fidelity Advisor&#xae; Sustainable Core Plus Bond Fund Class Z</oef:ClassName>
    <dei:TradingSymbol contextRef="C000235220_ClassMember" id="ixv-7188">FIAMX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000235220_ClassMember" id="ixv-7207">This annual shareholder report contains information about Fidelity&#xae; Sustainable Core Plus Bond Fund for the period September 1, 2024 to August 31, 2025.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000235220_ClassMember" id="ixv-7209">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000235220_ClassMember" id="ixv-7214">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="C000235220_ClassMember" id="ixv-7216">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000235220_ClassMember" id="ixv-7219">1-877-208-0098</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000235220_ClassMember" id="ixv-7222">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000235220_ClassMember" id="ixv-7229">&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:45%; 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:24%; 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:30%; 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 $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:45%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Class Z&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:24%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$ &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:30%; 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="C000235220_ClassMember"
      decimals="0"
      id="ixv-224990"
      unitRef="usd">37</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000235220_ClassMember"
      decimals="INF"
      id="ixv-224991"
      unitRef="pure">0.0036</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000235220_ClassMember" id="ixv-7271">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What affected the Fund's performance this period?&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;U.S. taxable investment-grade bonds posted a solid advance for the 12 months ending August 31, 2025, navigating tariff-related uncertainty since late 2024 but buoyed by relatively stable consumer inflation, a resilient economy and the expectation of policy interest-rate cuts by the U.S. Federal Reserve in the second half of 2025.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Against this backdrop, an allocation to high-yield bonds contributed to the fund's outperformance of the Bloomberg U.S. Aggregate Bond Index for the fiscal year.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Security selection also added value. Specifically, fund holdings in the corporate segment made a notable contribution to relative performance, led by picks among financials, particularly REITs and banks.&#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 and picks among collateralized loan obligations also helped.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;The fund's underweights in mortgage-backed securities and U.S. Treasurys buoyed relative performance as well.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;The portfolio's yield-curve positioning also provided a boost to performance versus the benchmark.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;In contrast, the fund's underweight in the bonds of industrial firms within the corporate sector detracted versus the benchmark.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;The fund's modestly longer duration relative to the benchmark 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;Notable changes over the past 12 months included management's decision to gradually lower the fund's overall risk profile by reducing exposure to investment-grade corporate bonds and increasing the allocation to U.S. Treasurys.&lt;/span&gt;&lt;/div&gt;
&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:italic;font-weight:normal;"&gt;Application of FMR's environmental, social, and governance (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;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:FactorsAffectingPerfTextBlock>
    <oef:LineGraphTableTextBlock contextRef="C000235220_ClassMember" id="ixv-7308">How did the Fund perform over the life of Fund?

 &#160;&#160;
CUMULATIVE PERFORMANCE
April 13, 2022 through August 31, 2025.
Initial investment of $10,000.
Class Z


$10,000

$9,595


$9,559


$10,308



Bloomberg MSCI U.S. Aggregate ESG Choice Bond Index


$10,000

$9,702


$9,590


$10,286



Bloomberg U.S. Aggregate Bond Index


$10,000

$9,696


$9,581


$10,280



&#160;

2022

2023

2024

2025









&#160;
</oef:LineGraphTableTextBlock>
    <oef:LineGraphAndTableMeasureName contextRef="C000235220_LG_ClassMember_4YR" id="ixv-7327">&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="C000235220_ClassMember_AsOf_2022"
      decimals="0"
      id="ixv-224992"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235220_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-224993"
      unitRef="usd">9595</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235220_ClassMember_AsOf_2024"
      decimals="0"
      id="ixv-224994"
      unitRef="usd">9559</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235220_ClassMember_AsOf_2025"
      decimals="0"
      id="ixv-224995"
      unitRef="usd">10308</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000235220_LG_1_AdditionalIndexMember_4YR"
      id="ixv-7348">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg MSCI U.S. Aggregate ESG Choice Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000235220_1_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-224996"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235220_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-224997"
      unitRef="usd">9702</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235220_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-224998"
      unitRef="usd">9590</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235220_1_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-224999"
      unitRef="usd">10286</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000235220_LG_2_AdditionalIndexMember_4YR"
      id="ixv-7369">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg U.S. Aggregate Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000235220_2_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-225000"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235220_2_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-225001"
      unitRef="usd">9696</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235220_2_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-225002"
      unitRef="usd">9581</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235220_2_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-225003"
      unitRef="usd">10280</oef:AccmVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000235220_ClassMember" id="ixv-7421">AVERAGE ANNUAL TOTAL RETURNS:

&#160;

1 Year

Life of Fund&#160;A


Class Z

3.58%

1.95%


Bloomberg MSCI U.S. Aggregate ESG Choice Bond Index

3.17%


1.77%


Bloomberg U.S. Aggregate Bond Index

3.14%


1.74%




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="C000235220_NoLoadClassMember_1YR"
      decimals="INF"
      id="ixv-225004"
      unitRef="pure">0.0358</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235220_NoLoadClassMember_2024-09-01_2025-08-31"
      decimals="INF"
      id="ixv-225005"
      unitRef="pure">0.0195</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235220_0_AdditionalIndexMember_1YR"
      decimals="INF"
      id="ixv-225006"
      unitRef="pure">0.0317</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235220_0_AdditionalIndexMember_LOC"
      decimals="INF"
      id="ixv-225007"
      unitRef="pure">0.0177</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235220_1_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-225008"
      unitRef="pure">0.0314</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235220_1_BBIndexMember_LOC"
      decimals="INF"
      id="ixv-225009"
      unitRef="pure">0.0174</oef:AvgAnnlRtrPct>
    <oef:PerfInceptionDate
      contextRef="C000235220_Perf_2022-04-13_ClassMember"
      id="ixv-7476">2022-04-13</oef:PerfInceptionDate>
    <oef:UpdPerfInfoLocationTextBlock contextRef="C000235220_ClassMember" id="ixv-7486">&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="C000235220_ClassMember" id="ixv-7498">&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="C000235220_ClassMember" id="ixv-7502">&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="C000235220_ClassMember" id="ixv-7508">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;Key Fund Statistics&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(as of August 31, 2025)&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;$&lt;/span&gt;47,786,486&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;699&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;145,078&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;201&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;
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&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:AddlFundStatisticsTextBlock>
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&#160;
U.S. Government and U.S. Government Agency Obligations

55.1


AAA

5.8


AA

0.9


A

10.6


BBB

14.8


BB

4.2


B

2.5


CCC,CC,C

1.7


D

0.0


Not Rated

1.4


Equities

0.0


Short-Term Investments and Net Other Assets (Liabilities)

3.0




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

U.S. Government and U.S. Government Agency Obligations - 55.1


&#160;

AAA - 5.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

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


&#160;

A - 10.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BBB - 14.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BB - 4.2&#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;

B - 2.5&#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;


&#160;

CCC,CC,C - 1.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

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


&#160;

Not Rated - 1.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

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


&#160;

Short-Term Investments and Net Other Assets (Liabilities) - 3.0


&#160;


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




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

38.9


Corporate Bonds

33.0


U.S. Government Agency - Mortgage Securities

16.2


Asset-Backed Securities

6.0


CMOs and Other Mortgage Related Securities

0.9


Bank Loan Obligations

0.8


Foreign Government and Government Agency Obligations

0.8


Preferred Securities

0.4


Preferred Stocks

0.0


Common Stocks

0.0


Short-Term Investments and Net Other Assets (Liabilities)

3.0




ASSET ALLOCATION (% of Fund's net assets)


&#160;



&#160;

U.S. Treasury Obligations - 38.9&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Corporate Bonds - 33.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

U.S. Government Agency - Mortgage Securities - 16.2


&#160;

Asset-Backed Securities - 6.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

CMOs and Other Mortgage Related Securities - 0.9


&#160;

Bank Loan Obligations - 0.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Foreign Government and Government Agency Obligations - 0.8


&#160;

Preferred Securities - 0.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

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


&#160;

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


&#160;

Short-Term Investments and Net Other Assets (Liabilities) - 3.0


&#160;






United States

83.6


Grand Cayman (UK Overseas Ter)

3.9


United Kingdom

2.5


Bailiwick Of Jersey

1.6


Italy

1.4


France

0.8


Netherlands

0.7


Canada

0.7


Germany

0.6


Others

4.2




GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

United States - 83.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Grand Cayman (UK Overseas Ter) - 3.9&#160;&#160;&#160;&#160;


&#160;

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


&#160;

Bailiwick Of Jersey - 1.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Italy - 1.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

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


&#160;

Netherlands - 0.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Canada - 0.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Germany - 0.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Others - 4.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;




&#160;




&#160;
&#160;
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    <oef:LargestHoldingsTableTextBlock contextRef="C000235220_ClassMember" id="ixv-8109">TOP HOLDINGS(% of Fund's net assets)

&#160;

&#160;


US Treasury Notes

27.4


&#160;


US Treasury Bonds

11.5


&#160;


Fannie Mae Mortgage pass-thru certificates

5.0


&#160;


Ginnie Mae II Pool

4.1


&#160;


Uniform Mortgage Backed Securities

3.0


&#160;


Freddie Mac Gold Pool

2.8


&#160;


Bank of America Corp

1.1


&#160;


Symphony Clo Xxvi Ltd / Symphony Clo Xxvi LLC

1.0


&#160;


AES Corp/The

0.7


&#160;


Enel Finance International NV

0.7


&#160;


&#160;

57.3

&#160;



</oef:LargestHoldingsTableTextBlock>
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    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-8280">2025-08-31</dei:DocumentPeriodEndDate>
    <oef:MaterialFundChngNoticeTextBlock contextRef="C000235222_ClassMember" id="ixv-8284">This report describes changes to the Fund that occurred during the reporting period.</oef:MaterialFundChngNoticeTextBlock>
    <oef:FundName contextRef="C000235222_ClassMember" id="ixv-8295">Fidelity&#xae; Sustainable Core Plus Bond Fund</oef:FundName>
    <oef:ClassName contextRef="C000235222_ClassMember" id="ixv-8298">Fidelity Advisor&#xae; Sustainable Core Plus Bond Fund Class M</oef:ClassName>
    <dei:TradingSymbol contextRef="C000235222_ClassMember" id="ixv-8302">FIAKX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000235222_ClassMember" id="ixv-8321">This annual shareholder report contains information about Fidelity&#xae; Sustainable Core Plus Bond Fund for the period September 1, 2024 to August 31, 2025.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000235222_ClassMember" id="ixv-8323">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000235222_ClassMember" id="ixv-8328">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="C000235222_ClassMember" id="ixv-8330">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000235222_ClassMember" id="ixv-8333">1-877-208-0098</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000235222_ClassMember" id="ixv-8336">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000235222_ClassMember" id="ixv-8343">&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:45%; 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:24%; 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:30%; 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 $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:45%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Class M&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:24%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$ &lt;/span&gt;75&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:30%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;0.74&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:ExpensesTextBlock>
    <oef:ExpensesPaidAmt
      contextRef="C000235222_ClassMember"
      decimals="0"
      id="ixv-225057"
      unitRef="usd">75</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000235222_ClassMember"
      decimals="INF"
      id="ixv-225058"
      unitRef="pure">0.0074</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000235222_ClassMember" id="ixv-8385">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What affected the Fund's performance this period?&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;U.S. taxable investment-grade bonds posted a solid advance for the 12 months ending August 31, 2025, navigating tariff-related uncertainty since late 2024 but buoyed by relatively stable consumer inflation, a resilient economy and the expectation of policy interest-rate cuts by the U.S. Federal Reserve in the second half of 2025.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Against this backdrop, an allocation to high-yield bonds contributed to the fund's outperformance of the Bloomberg U.S. Aggregate Bond Index for the fiscal year.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Security selection also added value. Specifically, fund holdings in the corporate segment made a notable contribution to relative performance, led by picks among financials, particularly REITs and banks.&#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 and picks among collateralized loan obligations also helped.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;The fund's underweights in mortgage-backed securities and U.S. Treasurys buoyed relative performance as well.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;The portfolio's yield-curve positioning also provided a boost to performance versus the benchmark.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;In contrast, the fund's underweight in the bonds of industrial firms within the corporate sector detracted versus the benchmark.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;The fund's modestly longer duration relative to the benchmark 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;Notable changes over the past 12 months included management's decision to gradually lower the fund's overall risk profile by reducing exposure to investment-grade corporate bonds and increasing the allocation to U.S. Treasurys.&lt;/span&gt;&lt;/div&gt;
&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:italic;font-weight:normal;"&gt;Application of FMR's environmental, social, and governance (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;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:FactorsAffectingPerfTextBlock>
    <oef:LineGraphTableTextBlock contextRef="C000235222_ClassMember" id="ixv-8422">How did the Fund perform over the life of Fund?

 &#160;&#160;
CUMULATIVE PERFORMANCE
April 13, 2022 through August 31, 2025.
Initial investment of $10,000&#160;and the current sales charge was paid.
Class M


$9,600

$9,202


$9,139


$9,814



Bloomberg MSCI U.S. Aggregate ESG Choice Bond Index


$10,000

$9,702


$9,590


$10,286



Bloomberg U.S. Aggregate Bond Index


$10,000

$9,696


$9,581


$10,280



&#160;

2022

2023

2024

2025









&#160;
</oef:LineGraphTableTextBlock>
    <oef:LineGraphAndTableMeasureName contextRef="C000235222_LG_ClassMember_4YR" id="ixv-8443">&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="C000235222_ClassMember_AsOf_2022"
      decimals="0"
      id="ixv-225059"
      unitRef="usd">9600</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235222_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-225060"
      unitRef="usd">9202</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235222_ClassMember_AsOf_2024"
      decimals="0"
      id="ixv-225061"
      unitRef="usd">9139</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235222_ClassMember_AsOf_2025"
      decimals="0"
      id="ixv-225062"
      unitRef="usd">9814</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000235222_LG_1_AdditionalIndexMember_4YR"
      id="ixv-8464">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg MSCI U.S. Aggregate ESG Choice Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000235222_1_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-225063"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235222_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-225064"
      unitRef="usd">9702</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235222_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-225065"
      unitRef="usd">9590</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235222_1_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-225066"
      unitRef="usd">10286</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000235222_LG_2_AdditionalIndexMember_4YR"
      id="ixv-8485">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg U.S. Aggregate Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000235222_2_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-225067"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235222_2_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-225068"
      unitRef="usd">9696</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235222_2_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-225069"
      unitRef="usd">9581</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235222_2_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-225070"
      unitRef="usd">10280</oef:AccmVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000235222_ClassMember" id="ixv-8537">AVERAGE ANNUAL TOTAL RETURNS:

&#160;

1 Year

Life of Fund&#160;A


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

-0.83%

0.41%


Class M (without 4.00% sales charge)

3.30%

1.62%


Bloomberg MSCI U.S. Aggregate ESG Choice Bond Index

3.17%


1.77%


Bloomberg U.S. Aggregate Bond Index

3.14%


1.74%




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="C000235222_ClassMember_1YR"
      decimals="INF"
      id="ixv-225071"
      unitRef="pure">-0.0083</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235222_ClassMember_2024-09-01_2025-08-31"
      decimals="INF"
      id="ixv-225072"
      unitRef="pure">0.0041</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235222_NoLoadClassMember_1YR"
      decimals="INF"
      id="ixv-225073"
      unitRef="pure">0.0330</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235222_NoLoadClassMember_2024-09-01_2025-08-31"
      decimals="INF"
      id="ixv-225074"
      unitRef="pure">0.0162</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235222_0_AdditionalIndexMember_1YR"
      decimals="INF"
      id="ixv-225075"
      unitRef="pure">0.0317</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235222_0_AdditionalIndexMember_LOC"
      decimals="INF"
      id="ixv-225076"
      unitRef="pure">0.0177</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235222_1_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-225077"
      unitRef="pure">0.0314</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235222_1_BBIndexMember_LOC"
      decimals="INF"
      id="ixv-225078"
      unitRef="pure">0.0174</oef:AvgAnnlRtrPct>
    <oef:PerfInceptionDate
      contextRef="C000235222_Perf_2022-04-13_ClassMember"
      id="ixv-8604">2022-04-13</oef:PerfInceptionDate>
    <oef:UpdPerfInfoLocationTextBlock contextRef="C000235222_ClassMember" id="ixv-8614">&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="C000235222_ClassMember" id="ixv-8626">&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="C000235222_ClassMember" id="ixv-8630">&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="C000235222_ClassMember" id="ixv-8636">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;Key Fund Statistics&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(as of August 31, 2025)&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;$&lt;/span&gt;47,786,486&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;699&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;145,078&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;201&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>
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      unitRef="usd">47786486</us-gaap:AssetsNet>
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    <oef:HoldingsTableTextBlock contextRef="C000235222_ClassMember" id="ixv-8711">
&#160;
U.S. Government and U.S. Government Agency Obligations

55.1


AAA

5.8


AA

0.9


A

10.6


BBB

14.8


BB

4.2


B

2.5


CCC,CC,C

1.7


D

0.0


Not Rated

1.4


Equities

0.0


Short-Term Investments and Net Other Assets (Liabilities)

3.0




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

U.S. Government and U.S. Government Agency Obligations - 55.1


&#160;

AAA - 5.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

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


&#160;

A - 10.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BBB - 14.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BB - 4.2&#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;

B - 2.5&#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;


&#160;

CCC,CC,C - 1.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

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


&#160;

Not Rated - 1.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

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


&#160;

Short-Term Investments and Net Other Assets (Liabilities) - 3.0


&#160;


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




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

38.9


Corporate Bonds

33.0


U.S. Government Agency - Mortgage Securities

16.2


Asset-Backed Securities

6.0


CMOs and Other Mortgage Related Securities

0.9


Bank Loan Obligations

0.8


Foreign Government and Government Agency Obligations

0.8


Preferred Securities

0.4


Preferred Stocks

0.0


Common Stocks

0.0


Short-Term Investments and Net Other Assets (Liabilities)

3.0




ASSET ALLOCATION (% of Fund's net assets)


&#160;



&#160;

U.S. Treasury Obligations - 38.9&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Corporate Bonds - 33.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

U.S. Government Agency - Mortgage Securities - 16.2


&#160;

Asset-Backed Securities - 6.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

CMOs and Other Mortgage Related Securities - 0.9


&#160;

Bank Loan Obligations - 0.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Foreign Government and Government Agency Obligations - 0.8


&#160;

Preferred Securities - 0.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

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


&#160;

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


&#160;

Short-Term Investments and Net Other Assets (Liabilities) - 3.0


&#160;






United States

83.6


Grand Cayman (UK Overseas Ter)

3.9


United Kingdom

2.5


Bailiwick Of Jersey

1.6


Italy

1.4


France

0.8


Netherlands

0.7


Canada

0.7


Germany

0.6


Others

4.2




GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

United States - 83.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Grand Cayman (UK Overseas Ter) - 3.9&#160;&#160;&#160;&#160;


&#160;

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


&#160;

Bailiwick Of Jersey - 1.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Italy - 1.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

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


&#160;

Netherlands - 0.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Canada - 0.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Germany - 0.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Others - 4.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;




&#160;




&#160;
&#160;
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    <oef:PctOfNav
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    <oef:PctOfNav
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      decimals="INF"
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    <oef:PctOfNav
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    <oef:PctOfNav
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    <oef:PctOfNav
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    <oef:PctOfNav
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    <oef:PctOfNav
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    <oef:PctOfNav
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    <oef:PctOfNav
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      id="ixv-225101"
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    <oef:PctOfNav
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      decimals="INF"
      id="ixv-225102"
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    <oef:PctOfNav
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      decimals="INF"
      id="ixv-225103"
      unitRef="pure">0.000</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
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      unitRef="pure">0.000</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235222_AA_ShortTermInvestmentsandNetOtherAssetsLiabilities_Member"
      decimals="INF"
      id="ixv-225105"
      unitRef="pure">0.030</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235222_GD_US_Member"
      decimals="INF"
      id="ixv-225106"
      unitRef="pure">0.836</oef:PctOfNav>
    <oef:PctOfNav
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      id="ixv-225107"
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    <oef:PctOfNav
      contextRef="C000235222_GD_GB_Member"
      decimals="INF"
      id="ixv-225108"
      unitRef="pure">0.025</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235222_GD_BailiwickOfJersey_Member"
      decimals="INF"
      id="ixv-225109"
      unitRef="pure">0.016</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-225110"
      unitRef="pure">0.014</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235222_GD_FR_Member"
      decimals="INF"
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      unitRef="pure">0.008</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-225112"
      unitRef="pure">0.007</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-225113"
      unitRef="pure">0.007</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235222_GD_DE_Member"
      decimals="INF"
      id="ixv-225114"
      unitRef="pure">0.006</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-225115"
      unitRef="pure">0.042</oef:PctOfNav>
    <oef:LargestHoldingsTableTextBlock contextRef="C000235222_ClassMember" id="ixv-9237">TOP HOLDINGS(% of Fund's net assets)

&#160;

&#160;


US Treasury Notes

27.4


&#160;


US Treasury Bonds

11.5


&#160;


Fannie Mae Mortgage pass-thru certificates

5.0


&#160;


Ginnie Mae II Pool

4.1


&#160;


Uniform Mortgage Backed Securities

3.0


&#160;


Freddie Mac Gold Pool

2.8


&#160;


Bank of America Corp

1.1


&#160;


Symphony Clo Xxvi Ltd / Symphony Clo Xxvi LLC

1.0


&#160;


AES Corp/The

0.7


&#160;


Enel Finance International NV

0.7


&#160;


&#160;

57.3

&#160;



</oef:LargestHoldingsTableTextBlock>
    <oef:PctOfNav
      contextRef="C000235222_TH_0_Member"
      decimals="INF"
      id="ixv-225116"
      unitRef="pure">0.274</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235222_TH_1_Member"
      decimals="INF"
      id="ixv-225117"
      unitRef="pure">0.115</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235222_TH_2_Member"
      decimals="INF"
      id="ixv-225118"
      unitRef="pure">0.050</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235222_TH_3_Member"
      decimals="INF"
      id="ixv-225119"
      unitRef="pure">0.041</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235222_TH_4_Member"
      decimals="INF"
      id="ixv-225120"
      unitRef="pure">0.030</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235222_TH_5_Member"
      decimals="INF"
      id="ixv-225121"
      unitRef="pure">0.028</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235222_TH_6_Member"
      decimals="INF"
      id="ixv-225122"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235222_TH_7_Member"
      decimals="INF"
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      unitRef="pure">0.010</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
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      unitRef="pure">0.007</oef:PctOfNav>
    <oef:PctOfNav
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    <oef:MaterialFundChngTextBlock contextRef="C000235222_ClassMember" id="ixv-9362">
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;How has the Fund changed?&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;This is a summary of certain changes to the Fund since September 1, 2024. 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;October 30, 2025 at &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;fundresearch.fidelity.com/prospectus/sec&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt; or upon request at &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;1-877-208-0098&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:0px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt; or by sending an e-mail to &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;fidfunddocuments@fidelity.com&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;table cellpadding="0" cellspacing="0" style="border-collapse:collapse;border-style:none;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:50%; background-color:#ebf3e9;border-right:2px dashed #368627;padding:19px 19px 19px 19px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;The fees associated with this class changed during the reporting year. The variations in class fees are primarily the result of the following changes:&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;ul style="color:#000000;list-style-type:disc;margin:0px 0px 0px 25px;padding:0px;"&gt;&lt;li style="margin:5px 0px 2px 24px;padding:0px 0px 0px 0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Operating expenses&lt;/span&gt;&lt;/li&gt;&lt;/ul&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;&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="C000235222_ClassMember" id="ixv-9368">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;This is a summary of certain changes to the Fund since September 1, 2024. 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;October 30, 2025 at &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;fundresearch.fidelity.com/prospectus/sec&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt; or upon request at &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;1-877-208-0098&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:0px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt; or by sending an e-mail to &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;fidfunddocuments@fidelity.com&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;.&lt;/span&gt;</oef:SummaryOfChngLegendTextBlock>
    <oef:UpdProspectusWebAddress contextRef="C000235222_ClassMember" id="ixv-9372">&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="C000235222_ClassMember" id="ixv-9375">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;1-877-208-0098&lt;/span&gt;</oef:UpdProspectusPhoneNumber>
    <oef:UpdProspectusEmailAddress contextRef="C000235222_ClassMember" id="ixv-9379">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;fidfunddocuments@fidelity.com&lt;/span&gt;</oef:UpdProspectusEmailAddress>
    <oef:MaterialFundChngExpensesTextBlock contextRef="C000235222_ClassMember" id="ixv-9390">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;The fees associated with this class changed during the reporting year. The variations in class fees are primarily the result of the following changes:&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;ul style="color:#000000;list-style-type:disc;margin:0px 0px 0px 25px;padding:0px;"&gt;&lt;li style="margin:5px 0px 2px 24px;padding:0px 0px 0px 0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Operating expenses&lt;/span&gt;&lt;/li&gt;&lt;/ul&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:MaterialFundChngExpensesTextBlock>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-9453">2025-08-31</dei:DocumentPeriodEndDate>
    <oef:MaterialFundChngNoticeTextBlock contextRef="C000235221_ClassMember" id="ixv-9457">This report describes changes to the Fund that occurred during the reporting period.</oef:MaterialFundChngNoticeTextBlock>
    <oef:FundName contextRef="C000235221_ClassMember" id="ixv-9468">Fidelity&#xae; Sustainable Core Plus Bond Fund</oef:FundName>
    <oef:ClassName contextRef="C000235221_ClassMember" id="ixv-9471">Fidelity Advisor&#xae; Sustainable Core Plus Bond Fund Class I</oef:ClassName>
    <dei:TradingSymbol contextRef="C000235221_ClassMember" id="ixv-9475">FIALX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000235221_ClassMember" id="ixv-9494">This annual shareholder report contains information about Fidelity&#xae; Sustainable Core Plus Bond Fund for the period September 1, 2024 to August 31, 2025.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000235221_ClassMember" id="ixv-9496">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000235221_ClassMember" id="ixv-9501">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="C000235221_ClassMember" id="ixv-9503">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000235221_ClassMember" id="ixv-9506">1-877-208-0098</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000235221_ClassMember" id="ixv-9509">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000235221_ClassMember" id="ixv-9516">&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:45%; 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:24%; 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:30%; 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 $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:45%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Class I&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:24%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$ &lt;/span&gt;46&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:30%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;0.45&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:ExpensesTextBlock>
    <oef:ExpensesPaidAmt
      contextRef="C000235221_ClassMember"
      decimals="0"
      id="ixv-225126"
      unitRef="usd">46</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000235221_ClassMember"
      decimals="INF"
      id="ixv-225127"
      unitRef="pure">0.0045</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000235221_ClassMember" id="ixv-9558">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What affected the Fund's performance this period?&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;U.S. taxable investment-grade bonds posted a solid advance for the 12 months ending August 31, 2025, navigating tariff-related uncertainty since late 2024 but buoyed by relatively stable consumer inflation, a resilient economy and the expectation of policy interest-rate cuts by the U.S. Federal Reserve in the second half of 2025.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Against this backdrop, an allocation to high-yield bonds contributed to the fund's outperformance of the Bloomberg U.S. Aggregate Bond Index for the fiscal year.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Security selection also added value. Specifically, fund holdings in the corporate segment made a notable contribution to relative performance, led by picks among financials, particularly REITs and banks.&#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 and picks among collateralized loan obligations also helped.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;The fund's underweights in mortgage-backed securities and U.S. Treasurys buoyed relative performance as well.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;The portfolio's yield-curve positioning also provided a boost to performance versus the benchmark.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;In contrast, the fund's underweight in the bonds of industrial firms within the corporate sector detracted versus the benchmark.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;The fund's modestly longer duration relative to the benchmark 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;Notable changes over the past 12 months included management's decision to gradually lower the fund's overall risk profile by reducing exposure to investment-grade corporate bonds and increasing the allocation to U.S. Treasurys.&lt;/span&gt;&lt;/div&gt;
&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:italic;font-weight:normal;"&gt;Application of FMR's environmental, social, and governance (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;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:FactorsAffectingPerfTextBlock>
    <oef:LineGraphTableTextBlock contextRef="C000235221_ClassMember" id="ixv-9595">How did the Fund perform over the life of Fund?

 &#160;&#160;
CUMULATIVE PERFORMANCE
April 13, 2022 through August 31, 2025.
Initial investment of $10,000.
Class I


$10,000

$9,594


$9,553


$10,284



Bloomberg MSCI U.S. Aggregate ESG Choice Bond Index


$10,000

$9,702


$9,590


$10,286



Bloomberg U.S. Aggregate Bond Index


$10,000

$9,696


$9,581


$10,280



&#160;

2022

2023

2024

2025









&#160;
</oef:LineGraphTableTextBlock>
    <oef:LineGraphAndTableMeasureName contextRef="C000235221_LG_ClassMember_4YR" id="ixv-9614">&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="C000235221_ClassMember_AsOf_2022"
      decimals="0"
      id="ixv-225128"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235221_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-225129"
      unitRef="usd">9594</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235221_ClassMember_AsOf_2024"
      decimals="0"
      id="ixv-225130"
      unitRef="usd">9553</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235221_ClassMember_AsOf_2025"
      decimals="0"
      id="ixv-225131"
      unitRef="usd">10284</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000235221_LG_1_AdditionalIndexMember_4YR"
      id="ixv-9635">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg MSCI U.S. Aggregate ESG Choice Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000235221_1_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-225132"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235221_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-225133"
      unitRef="usd">9702</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235221_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-225134"
      unitRef="usd">9590</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235221_1_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-225135"
      unitRef="usd">10286</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000235221_LG_2_AdditionalIndexMember_4YR"
      id="ixv-9656">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg U.S. Aggregate Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000235221_2_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-225136"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235221_2_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-225137"
      unitRef="usd">9696</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235221_2_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-225138"
      unitRef="usd">9581</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235221_2_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-225139"
      unitRef="usd">10280</oef:AccmVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000235221_ClassMember" id="ixv-9708">AVERAGE ANNUAL TOTAL RETURNS:

&#160;

1 Year

Life of Fund&#160;A


Class I

3.60%

1.89%


Bloomberg MSCI U.S. Aggregate ESG Choice Bond Index

3.17%


1.77%


Bloomberg U.S. Aggregate Bond Index

3.14%


1.74%




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="C000235221_NoLoadClassMember_1YR"
      decimals="INF"
      id="ixv-225140"
      unitRef="pure">0.0360</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235221_NoLoadClassMember_2024-09-01_2025-08-31"
      decimals="INF"
      id="ixv-225141"
      unitRef="pure">0.0189</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235221_0_AdditionalIndexMember_1YR"
      decimals="INF"
      id="ixv-225142"
      unitRef="pure">0.0317</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235221_0_AdditionalIndexMember_LOC"
      decimals="INF"
      id="ixv-225143"
      unitRef="pure">0.0177</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235221_1_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-225144"
      unitRef="pure">0.0314</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235221_1_BBIndexMember_LOC"
      decimals="INF"
      id="ixv-225145"
      unitRef="pure">0.0174</oef:AvgAnnlRtrPct>
    <oef:PerfInceptionDate
      contextRef="C000235221_Perf_2022-04-13_ClassMember"
      id="ixv-9763">2022-04-13</oef:PerfInceptionDate>
    <oef:UpdPerfInfoLocationTextBlock contextRef="C000235221_ClassMember" id="ixv-9773">&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="C000235221_ClassMember" id="ixv-9785">&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="C000235221_ClassMember" id="ixv-9789">&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="C000235221_ClassMember" id="ixv-9795">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;Key Fund Statistics&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(as of August 31, 2025)&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;$&lt;/span&gt;47,786,486&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;699&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;145,078&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;201&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>
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&#160;
U.S. Government and U.S. Government Agency Obligations

55.1


AAA

5.8


AA

0.9


A

10.6


BBB

14.8


BB

4.2


B

2.5


CCC,CC,C

1.7


D

0.0


Not Rated

1.4


Equities

0.0


Short-Term Investments and Net Other Assets (Liabilities)

3.0




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

U.S. Government and U.S. Government Agency Obligations - 55.1


&#160;

AAA - 5.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

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


&#160;

A - 10.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BBB - 14.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BB - 4.2&#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;

B - 2.5&#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;


&#160;

CCC,CC,C - 1.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

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


&#160;

Not Rated - 1.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

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


&#160;

Short-Term Investments and Net Other Assets (Liabilities) - 3.0


&#160;


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




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

38.9


Corporate Bonds

33.0


U.S. Government Agency - Mortgage Securities

16.2


Asset-Backed Securities

6.0


CMOs and Other Mortgage Related Securities

0.9


Bank Loan Obligations

0.8


Foreign Government and Government Agency Obligations

0.8


Preferred Securities

0.4


Preferred Stocks

0.0


Common Stocks

0.0


Short-Term Investments and Net Other Assets (Liabilities)

3.0




ASSET ALLOCATION (% of Fund's net assets)


&#160;



&#160;

U.S. Treasury Obligations - 38.9&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Corporate Bonds - 33.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

U.S. Government Agency - Mortgage Securities - 16.2


&#160;

Asset-Backed Securities - 6.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

CMOs and Other Mortgage Related Securities - 0.9


&#160;

Bank Loan Obligations - 0.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Foreign Government and Government Agency Obligations - 0.8


&#160;

Preferred Securities - 0.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

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


&#160;

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


&#160;

Short-Term Investments and Net Other Assets (Liabilities) - 3.0


&#160;






United States

83.6


Grand Cayman (UK Overseas Ter)

3.9


United Kingdom

2.5


Bailiwick Of Jersey

1.6


Italy

1.4


France

0.8


Netherlands

0.7


Canada

0.7


Germany

0.6


Others

4.2




GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

United States - 83.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Grand Cayman (UK Overseas Ter) - 3.9&#160;&#160;&#160;&#160;


&#160;

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


&#160;

Bailiwick Of Jersey - 1.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Italy - 1.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

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


&#160;

Netherlands - 0.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Canada - 0.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Germany - 0.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Others - 4.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;




&#160;




&#160;
&#160;
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    <oef:LargestHoldingsTableTextBlock contextRef="C000235221_ClassMember" id="ixv-10396">TOP HOLDINGS(% of Fund's net assets)

&#160;

&#160;


US Treasury Notes

27.4


&#160;


US Treasury Bonds

11.5


&#160;


Fannie Mae Mortgage pass-thru certificates

5.0


&#160;


Ginnie Mae II Pool

4.1


&#160;


Uniform Mortgage Backed Securities

3.0


&#160;


Freddie Mac Gold Pool

2.8


&#160;


Bank of America Corp

1.1


&#160;


Symphony Clo Xxvi Ltd / Symphony Clo Xxvi LLC

1.0


&#160;


AES Corp/The

0.7


&#160;


Enel Finance International NV

0.7


&#160;


&#160;

57.3

&#160;



</oef:LargestHoldingsTableTextBlock>
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      unitRef="pure">0.010</oef:PctOfNav>
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      contextRef="C000235221_TH_8_Member"
      decimals="INF"
      id="ixv-225191"
      unitRef="pure">0.007</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235221_TH_9_Member"
      decimals="INF"
      id="ixv-225192"
      unitRef="pure">0.007</oef:PctOfNav>
    <oef:MaterialFundChngTextBlock contextRef="C000235221_ClassMember" id="ixv-10521">
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;How has the Fund changed?&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;This is a summary of certain changes to the Fund since September 1, 2024. 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;October 30, 2025 at &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;fundresearch.fidelity.com/prospectus/sec&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt; or upon request at &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;1-877-208-0098&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:0px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt; or by sending an e-mail to &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;fidfunddocuments@fidelity.com&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;table cellpadding="0" cellspacing="0" style="border-collapse:collapse;border-style:none;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:50%; background-color:#ebf3e9;border-right:2px dashed #368627;padding:19px 19px 19px 19px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;The fees associated with this class changed during the reporting year. The variations in class fees are primarily the result of the following changes:&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;ul style="color:#000000;list-style-type:disc;margin:0px 0px 0px 25px;padding:0px;"&gt;&lt;li style="margin:5px 0px 2px 24px;padding:0px 0px 0px 0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Operating expenses&lt;/span&gt;&lt;/li&gt;&lt;li style="margin:5px 0px 2px 24px;padding:0px 0px 0px 0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Expense reductions&lt;/span&gt;&lt;/li&gt;&lt;/ul&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;&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="C000235221_ClassMember" id="ixv-10527">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;This is a summary of certain changes to the Fund since September 1, 2024. 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;October 30, 2025 at &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;fundresearch.fidelity.com/prospectus/sec&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt; or upon request at &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;1-877-208-0098&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:0px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt; or by sending an e-mail to &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;fidfunddocuments@fidelity.com&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;.&lt;/span&gt;</oef:SummaryOfChngLegendTextBlock>
    <oef:UpdProspectusWebAddress contextRef="C000235221_ClassMember" id="ixv-10531">&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="C000235221_ClassMember" id="ixv-10534">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;1-877-208-0098&lt;/span&gt;</oef:UpdProspectusPhoneNumber>
    <oef:UpdProspectusEmailAddress contextRef="C000235221_ClassMember" id="ixv-10538">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;fidfunddocuments@fidelity.com&lt;/span&gt;</oef:UpdProspectusEmailAddress>
    <oef:MaterialFundChngExpensesTextBlock contextRef="C000235221_ClassMember" id="ixv-10549">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;The fees associated with this class changed during the reporting year. The variations in class fees are primarily the result of the following changes:&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;ul style="color:#000000;list-style-type:disc;margin:0px 0px 0px 25px;padding:0px;"&gt;&lt;li style="margin:5px 0px 2px 24px;padding:0px 0px 0px 0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Operating expenses&lt;/span&gt;&lt;/li&gt;&lt;li style="margin:5px 0px 2px 24px;padding:0px 0px 0px 0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Expense reductions&lt;/span&gt;&lt;/li&gt;&lt;/ul&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:MaterialFundChngExpensesTextBlock>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-10614">2025-08-31</dei:DocumentPeriodEndDate>
    <oef:MaterialFundChngNoticeTextBlock contextRef="C000235218_ClassMember" id="ixv-10618">This report describes changes to the Fund that occurred during the reporting period.</oef:MaterialFundChngNoticeTextBlock>
    <oef:FundName contextRef="C000235218_ClassMember" id="ixv-10629">Fidelity&#xae; Sustainable Core Plus Bond Fund</oef:FundName>
    <oef:ClassName contextRef="C000235218_ClassMember" id="ixv-10632">Fidelity Advisor&#xae; Sustainable Core Plus Bond Fund Class C</oef:ClassName>
    <dei:TradingSymbol contextRef="C000235218_ClassMember" id="ixv-10636">FIAJX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000235218_ClassMember" id="ixv-10655">This annual shareholder report contains information about Fidelity&#xae; Sustainable Core Plus Bond Fund for the period September 1, 2024 to August 31, 2025.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000235218_ClassMember" id="ixv-10657">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000235218_ClassMember" id="ixv-10662">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="C000235218_ClassMember" id="ixv-10664">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000235218_ClassMember" id="ixv-10667">1-877-208-0098</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000235218_ClassMember" id="ixv-10670">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000235218_ClassMember" id="ixv-10677">&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:45%; 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:24%; 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:30%; 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 $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:45%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Class C&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:24%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$ &lt;/span&gt;151&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:30%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;1.49&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:ExpensesTextBlock>
    <oef:ExpensesPaidAmt
      contextRef="C000235218_ClassMember"
      decimals="0"
      id="ixv-225193"
      unitRef="usd">151</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000235218_ClassMember"
      decimals="INF"
      id="ixv-225194"
      unitRef="pure">0.0149</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000235218_ClassMember" id="ixv-10719">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What affected the Fund's performance this period?&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;U.S. taxable investment-grade bonds posted a solid advance for the 12 months ending August 31, 2025, navigating tariff-related uncertainty since late 2024 but buoyed by relatively stable consumer inflation, a resilient economy and the expectation of policy interest-rate cuts by the U.S. Federal Reserve in the second half of 2025.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Against this backdrop, an allocation to high-yield bonds contributed to the fund's outperformance of the Bloomberg U.S. Aggregate Bond Index for the fiscal year.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Security selection also added value. Specifically, fund holdings in the corporate segment made a notable contribution to relative performance, led by picks among financials, particularly REITs and banks.&#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 and picks among collateralized loan obligations also helped.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;The fund's underweights in mortgage-backed securities and U.S. Treasurys buoyed relative performance as well.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;The portfolio's yield-curve positioning also provided a boost to performance versus the benchmark.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;In contrast, the fund's underweight in the bonds of industrial firms within the corporate sector detracted versus the benchmark.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;The fund's modestly longer duration relative to the benchmark 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;Notable changes over the past 12 months included management's decision to gradually lower the fund's overall risk profile by reducing exposure to investment-grade corporate bonds and increasing the allocation to U.S. Treasurys.&lt;/span&gt;&lt;/div&gt;
&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:italic;font-weight:normal;"&gt;Application of FMR's environmental, social, and governance (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;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:FactorsAffectingPerfTextBlock>
    <oef:LineGraphTableTextBlock contextRef="C000235218_ClassMember" id="ixv-10756">How did the Fund perform over the life of Fund?

 &#160;&#160;
CUMULATIVE PERFORMANCE
April 13, 2022 through August 31, 2025.
Initial investment of $10,000.
Class C


$10,000

$9,559


$9,423


$10,046



Bloomberg MSCI U.S. Aggregate ESG Choice Bond Index


$10,000

$9,702


$9,590


$10,286



Bloomberg U.S. Aggregate Bond Index


$10,000

$9,696


$9,581


$10,280



&#160;

2022

2023

2024

2025









&#160;
</oef:LineGraphTableTextBlock>
    <oef:LineGraphAndTableMeasureName contextRef="C000235218_LG_ClassMember_4YR" id="ixv-10775">&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="C000235218_ClassMember_AsOf_2022"
      decimals="0"
      id="ixv-225195"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235218_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-225196"
      unitRef="usd">9559</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235218_ClassMember_AsOf_2024"
      decimals="0"
      id="ixv-225197"
      unitRef="usd">9423</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235218_ClassMember_AsOf_2025"
      decimals="0"
      id="ixv-225198"
      unitRef="usd">10046</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000235218_LG_1_AdditionalIndexMember_4YR"
      id="ixv-10796">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg MSCI U.S. Aggregate ESG Choice Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000235218_1_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-225199"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235218_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-225200"
      unitRef="usd">9702</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235218_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-225201"
      unitRef="usd">9590</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235218_1_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-225202"
      unitRef="usd">10286</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000235218_LG_2_AdditionalIndexMember_4YR"
      id="ixv-10817">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg U.S. Aggregate Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000235218_2_AdditionalIndexMember_AsOf_2022"
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      id="ixv-225203"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235218_2_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-225204"
      unitRef="usd">9696</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235218_2_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-225205"
      unitRef="usd">9581</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235218_2_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-225206"
      unitRef="usd">10280</oef:AccmVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000235218_ClassMember" id="ixv-10869">AVERAGE ANNUAL TOTAL RETURNS:

&#160;

1 Year

Life of Fund&#160;A


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

1.43%

0.85%


Class C

2.43%

0.85%


Bloomberg MSCI U.S. Aggregate ESG Choice Bond Index

3.17%


1.77%


Bloomberg U.S. Aggregate Bond Index

3.14%


1.74%




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="C000235218_ClassMember_1YR"
      decimals="INF"
      id="ixv-225207"
      unitRef="pure">0.0143</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235218_ClassMember_2024-09-01_2025-08-31"
      decimals="INF"
      id="ixv-225208"
      unitRef="pure">0.0085</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235218_NoLoadClassMember_1YR"
      decimals="INF"
      id="ixv-225209"
      unitRef="pure">0.0243</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235218_NoLoadClassMember_2024-09-01_2025-08-31"
      decimals="INF"
      id="ixv-225210"
      unitRef="pure">0.0085</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235218_0_AdditionalIndexMember_1YR"
      decimals="INF"
      id="ixv-225211"
      unitRef="pure">0.0317</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235218_0_AdditionalIndexMember_LOC"
      decimals="INF"
      id="ixv-225212"
      unitRef="pure">0.0177</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235218_1_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-225213"
      unitRef="pure">0.0314</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235218_1_BBIndexMember_LOC"
      decimals="INF"
      id="ixv-225214"
      unitRef="pure">0.0174</oef:AvgAnnlRtrPct>
    <oef:PerfInceptionDate
      contextRef="C000235218_Perf_2022-04-13_ClassMember"
      id="ixv-10936">2022-04-13</oef:PerfInceptionDate>
    <oef:UpdPerfInfoLocationTextBlock contextRef="C000235218_ClassMember" id="ixv-10946">&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="C000235218_ClassMember" id="ixv-10958">&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="C000235218_ClassMember" id="ixv-10962">&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="C000235218_ClassMember" id="ixv-10968">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;Key Fund Statistics&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(as of August 31, 2025)&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;$&lt;/span&gt;47,786,486&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;699&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;145,078&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;201&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-225215"
      unitRef="usd">47786486</us-gaap:AssetsNet>
    <oef:HoldingsCount
      contextRef="C000235218_InstantMember"
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      unitRef="holding">699</oef:HoldingsCount>
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    <oef:HoldingsTableTextBlock contextRef="C000235218_ClassMember" id="ixv-11043">
&#160;
U.S. Government and U.S. Government Agency Obligations

55.1


AAA

5.8


AA

0.9


A

10.6


BBB

14.8


BB

4.2


B

2.5


CCC,CC,C

1.7


D

0.0


Not Rated

1.4


Equities

0.0


Short-Term Investments and Net Other Assets (Liabilities)

3.0




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

U.S. Government and U.S. Government Agency Obligations - 55.1


&#160;

AAA - 5.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

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


&#160;

A - 10.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BBB - 14.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BB - 4.2&#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;

B - 2.5&#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;


&#160;

CCC,CC,C - 1.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

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


&#160;

Not Rated - 1.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

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


&#160;

Short-Term Investments and Net Other Assets (Liabilities) - 3.0


&#160;


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




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

38.9


Corporate Bonds

33.0


U.S. Government Agency - Mortgage Securities

16.2


Asset-Backed Securities

6.0


CMOs and Other Mortgage Related Securities

0.9


Bank Loan Obligations

0.8


Foreign Government and Government Agency Obligations

0.8


Preferred Securities

0.4


Preferred Stocks

0.0


Common Stocks

0.0


Short-Term Investments and Net Other Assets (Liabilities)

3.0




ASSET ALLOCATION (% of Fund's net assets)


&#160;



&#160;

U.S. Treasury Obligations - 38.9&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Corporate Bonds - 33.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

U.S. Government Agency - Mortgage Securities - 16.2


&#160;

Asset-Backed Securities - 6.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

CMOs and Other Mortgage Related Securities - 0.9


&#160;

Bank Loan Obligations - 0.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Foreign Government and Government Agency Obligations - 0.8


&#160;

Preferred Securities - 0.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

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


&#160;

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


&#160;

Short-Term Investments and Net Other Assets (Liabilities) - 3.0


&#160;






United States

83.6


Grand Cayman (UK Overseas Ter)

3.9


United Kingdom

2.5


Bailiwick Of Jersey

1.6


Italy

1.4


France

0.8


Netherlands

0.7


Canada

0.7


Germany

0.6


Others

4.2




GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

United States - 83.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Grand Cayman (UK Overseas Ter) - 3.9&#160;&#160;&#160;&#160;


&#160;

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


&#160;

Bailiwick Of Jersey - 1.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Italy - 1.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

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


&#160;

Netherlands - 0.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Canada - 0.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Germany - 0.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Others - 4.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;




&#160;




&#160;
&#160;
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    <oef:PctOfNav
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    <oef:PctOfNav
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      id="ixv-225226"
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      contextRef="C000235218_AA_CorporateBonds_Member"
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      id="ixv-225232"
      unitRef="pure">0.330</oef:PctOfNav>
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      contextRef="C000235218_AA_USGovernmentAgencyMortgageSecurities_Member"
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      id="ixv-225233"
      unitRef="pure">0.162</oef:PctOfNav>
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      id="ixv-225234"
      unitRef="pure">0.060</oef:PctOfNav>
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      id="ixv-225235"
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      decimals="INF"
      id="ixv-225236"
      unitRef="pure">0.008</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235218_AA_ForeignGovernmentandGovernmentAgencyObligations_Member"
      decimals="INF"
      id="ixv-225237"
      unitRef="pure">0.008</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235218_AA_PreferredSecurities_Member"
      decimals="INF"
      id="ixv-225238"
      unitRef="pure">0.004</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235218_AA_PreferredStocks_Member"
      decimals="INF"
      id="ixv-225239"
      unitRef="pure">0.000</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235218_AA_CommonStocks_Member"
      decimals="INF"
      id="ixv-225240"
      unitRef="pure">0.000</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235218_AA_ShortTermInvestmentsandNetOtherAssetsLiabilities_Member"
      decimals="INF"
      id="ixv-225241"
      unitRef="pure">0.030</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235218_GD_US_Member"
      decimals="INF"
      id="ixv-225242"
      unitRef="pure">0.836</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235218_GD_GrandCaymanUKOverseasTer_Member"
      decimals="INF"
      id="ixv-225243"
      unitRef="pure">0.039</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235218_GD_GB_Member"
      decimals="INF"
      id="ixv-225244"
      unitRef="pure">0.025</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235218_GD_BailiwickOfJersey_Member"
      decimals="INF"
      id="ixv-225245"
      unitRef="pure">0.016</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235218_GD_IT_Member"
      decimals="INF"
      id="ixv-225246"
      unitRef="pure">0.014</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235218_GD_FR_Member"
      decimals="INF"
      id="ixv-225247"
      unitRef="pure">0.008</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-225248"
      unitRef="pure">0.007</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-225249"
      unitRef="pure">0.007</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-225250"
      unitRef="pure">0.006</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
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      unitRef="pure">0.042</oef:PctOfNav>
    <oef:LargestHoldingsTableTextBlock contextRef="C000235218_ClassMember" id="ixv-11569">TOP HOLDINGS(% of Fund's net assets)

&#160;

&#160;


US Treasury Notes

27.4


&#160;


US Treasury Bonds

11.5


&#160;


Fannie Mae Mortgage pass-thru certificates

5.0


&#160;


Ginnie Mae II Pool

4.1


&#160;


Uniform Mortgage Backed Securities

3.0


&#160;


Freddie Mac Gold Pool

2.8


&#160;


Bank of America Corp

1.1


&#160;


Symphony Clo Xxvi Ltd / Symphony Clo Xxvi LLC

1.0


&#160;


AES Corp/The

0.7


&#160;


Enel Finance International NV

0.7


&#160;


&#160;

57.3

&#160;



</oef:LargestHoldingsTableTextBlock>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-225252"
      unitRef="pure">0.274</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-225253"
      unitRef="pure">0.115</oef:PctOfNav>
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      id="ixv-225254"
      unitRef="pure">0.050</oef:PctOfNav>
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      id="ixv-225255"
      unitRef="pure">0.041</oef:PctOfNav>
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      decimals="INF"
      id="ixv-225256"
      unitRef="pure">0.030</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-225257"
      unitRef="pure">0.028</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235218_TH_6_Member"
      decimals="INF"
      id="ixv-225258"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-225259"
      unitRef="pure">0.010</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-225260"
      unitRef="pure">0.007</oef:PctOfNav>
    <oef:PctOfNav
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      id="ixv-225261"
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    <oef:MaterialFundChngTextBlock contextRef="C000235218_ClassMember" id="ixv-11694">
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;How has the Fund changed?&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;This is a summary of certain changes to the Fund since September 1, 2024. 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;October 30, 2025 at &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;fundresearch.fidelity.com/prospectus/sec&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt; or upon request at &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;1-877-208-0098&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:0px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt; or by sending an e-mail to &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;fidfunddocuments@fidelity.com&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;table cellpadding="0" cellspacing="0" style="border-collapse:collapse;border-style:none;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:50%; background-color:#ebf3e9;border-right:2px dashed #368627;padding:19px 19px 19px 19px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;The fees associated with this class changed during the reporting year. The variations in class fees are primarily the result of the following changes:&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;ul style="color:#000000;list-style-type:disc;margin:0px 0px 0px 25px;padding:0px;"&gt;&lt;li style="margin:5px 0px 2px 24px;padding:0px 0px 0px 0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Operating expenses&lt;/span&gt;&lt;/li&gt;&lt;/ul&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;&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="C000235218_ClassMember" id="ixv-11700">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;This is a summary of certain changes to the Fund since September 1, 2024. 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;October 30, 2025 at &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;fundresearch.fidelity.com/prospectus/sec&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt; or upon request at &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;1-877-208-0098&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:0px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt; or by sending an e-mail to &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;fidfunddocuments@fidelity.com&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;.&lt;/span&gt;</oef:SummaryOfChngLegendTextBlock>
    <oef:UpdProspectusWebAddress contextRef="C000235218_ClassMember" id="ixv-11704">&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="C000235218_ClassMember" id="ixv-11707">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;1-877-208-0098&lt;/span&gt;</oef:UpdProspectusPhoneNumber>
    <oef:UpdProspectusEmailAddress contextRef="C000235218_ClassMember" id="ixv-11711">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;fidfunddocuments@fidelity.com&lt;/span&gt;</oef:UpdProspectusEmailAddress>
    <oef:MaterialFundChngExpensesTextBlock contextRef="C000235218_ClassMember" id="ixv-11722">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;The fees associated with this class changed during the reporting year. The variations in class fees are primarily the result of the following changes:&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;ul style="color:#000000;list-style-type:disc;margin:0px 0px 0px 25px;padding:0px;"&gt;&lt;li style="margin:5px 0px 2px 24px;padding:0px 0px 0px 0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Operating expenses&lt;/span&gt;&lt;/li&gt;&lt;/ul&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:MaterialFundChngExpensesTextBlock>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-11785">2025-08-31</dei:DocumentPeriodEndDate>
    <oef:FundName contextRef="C000235219_ClassMember" id="ixv-11797">Fidelity&#xae; Sustainable Core Plus Bond Fund</oef:FundName>
    <oef:ClassName contextRef="C000235219_ClassMember" id="ixv-11800">Fidelity Advisor&#xae; Sustainable Core Plus Bond Fund Class A</oef:ClassName>
    <dei:TradingSymbol contextRef="C000235219_ClassMember" id="ixv-11804">FIAIX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000235219_ClassMember" id="ixv-11823">This annual shareholder report contains information about Fidelity&#xae; Sustainable Core Plus Bond Fund for the period September 1, 2024 to August 31, 2025.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000235219_ClassMember" id="ixv-11825">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000235219_ClassMember" id="ixv-11830">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="C000235219_ClassMember" id="ixv-11832">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000235219_ClassMember" id="ixv-11835">1-877-208-0098</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000235219_ClassMember" id="ixv-11838">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000235219_ClassMember" id="ixv-11845">&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:45%; 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:24%; 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:30%; 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 $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:45%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Class A&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:24%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$ &lt;/span&gt;69&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:30%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;0.67&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:ExpensesTextBlock>
    <oef:ExpensesPaidAmt
      contextRef="C000235219_ClassMember"
      decimals="0"
      id="ixv-225262"
      unitRef="usd">69</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000235219_ClassMember"
      decimals="INF"
      id="ixv-225263"
      unitRef="pure">0.0067</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000235219_ClassMember" id="ixv-11887">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What affected the Fund's performance this period?&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;U.S. taxable investment-grade bonds posted a solid advance for the 12 months ending August 31, 2025, navigating tariff-related uncertainty since late 2024 but buoyed by relatively stable consumer inflation, a resilient economy and the expectation of policy interest-rate cuts by the U.S. Federal Reserve in the second half of 2025.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Against this backdrop, an allocation to high-yield bonds contributed to the fund's outperformance of the Bloomberg U.S. Aggregate Bond Index for the fiscal year.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Security selection also added value. Specifically, fund holdings in the corporate segment made a notable contribution to relative performance, led by picks among financials, particularly REITs and banks.&#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 and picks among collateralized loan obligations also helped.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;The fund's underweights in mortgage-backed securities and U.S. Treasurys buoyed relative performance as well.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;The portfolio's yield-curve positioning also provided a boost to performance versus the benchmark.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;In contrast, the fund's underweight in the bonds of industrial firms within the corporate sector detracted versus the benchmark.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;The fund's modestly longer duration relative to the benchmark 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;Notable changes over the past 12 months included management's decision to gradually lower the fund's overall risk profile by reducing exposure to investment-grade corporate bonds and increasing the allocation to U.S. Treasurys.&lt;/span&gt;&lt;/div&gt;
&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:italic;font-weight:normal;"&gt;Application of FMR's environmental, social, and governance (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;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:FactorsAffectingPerfTextBlock>
    <oef:LineGraphTableTextBlock contextRef="C000235219_ClassMember" id="ixv-11924">How did the Fund perform over the life of Fund?

 &#160;&#160;
CUMULATIVE PERFORMANCE
April 13, 2022 through August 31, 2025.
Initial investment of $10,000&#160;and the current sales charge was paid.
Class A


$9,600

$9,202


$9,137


$9,812



Bloomberg MSCI U.S. Aggregate ESG Choice Bond Index


$10,000

$9,702


$9,590


$10,286



Bloomberg U.S. Aggregate Bond Index


$10,000

$9,696


$9,581


$10,280



&#160;

2022

2023

2024

2025









&#160;
</oef:LineGraphTableTextBlock>
    <oef:LineGraphAndTableMeasureName contextRef="C000235219_LG_ClassMember_4YR" id="ixv-11945">&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="C000235219_ClassMember_AsOf_2022"
      decimals="0"
      id="ixv-225264"
      unitRef="usd">9600</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235219_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-225265"
      unitRef="usd">9202</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235219_ClassMember_AsOf_2024"
      decimals="0"
      id="ixv-225266"
      unitRef="usd">9137</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235219_ClassMember_AsOf_2025"
      decimals="0"
      id="ixv-225267"
      unitRef="usd">9812</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000235219_LG_1_AdditionalIndexMember_4YR"
      id="ixv-11966">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg MSCI U.S. Aggregate ESG Choice Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000235219_1_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-225268"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235219_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-225269"
      unitRef="usd">9702</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235219_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-225270"
      unitRef="usd">9590</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235219_1_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-225271"
      unitRef="usd">10286</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000235219_LG_2_AdditionalIndexMember_4YR"
      id="ixv-11987">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg U.S. Aggregate Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000235219_2_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-225272"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235219_2_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-225273"
      unitRef="usd">9696</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235219_2_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-225274"
      unitRef="usd">9581</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235219_2_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-225275"
      unitRef="usd">10280</oef:AccmVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000235219_ClassMember" id="ixv-12039">AVERAGE ANNUAL TOTAL RETURNS:

&#160;

1 Year

Life of Fund&#160;A


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

-0.76%

0.42%


Class A (without 4.00% sales charge)

3.37%

1.64%


Bloomberg MSCI U.S. Aggregate ESG Choice Bond Index

3.17%


1.77%


Bloomberg U.S. Aggregate Bond Index

3.14%


1.74%




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="C000235219_ClassMember_1YR"
      decimals="INF"
      id="ixv-225276"
      unitRef="pure">-0.0076</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235219_ClassMember_2024-09-01_2025-08-31"
      decimals="INF"
      id="ixv-225277"
      unitRef="pure">0.0042</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235219_NoLoadClassMember_1YR"
      decimals="INF"
      id="ixv-225278"
      unitRef="pure">0.0337</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235219_NoLoadClassMember_2024-09-01_2025-08-31"
      decimals="INF"
      id="ixv-225279"
      unitRef="pure">0.0164</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235219_0_AdditionalIndexMember_1YR"
      decimals="INF"
      id="ixv-225280"
      unitRef="pure">0.0317</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235219_0_AdditionalIndexMember_LOC"
      decimals="INF"
      id="ixv-225281"
      unitRef="pure">0.0177</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235219_1_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-225282"
      unitRef="pure">0.0314</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235219_1_BBIndexMember_LOC"
      decimals="INF"
      id="ixv-225283"
      unitRef="pure">0.0174</oef:AvgAnnlRtrPct>
    <oef:PerfInceptionDate
      contextRef="C000235219_Perf_2022-04-13_ClassMember"
      id="ixv-12106">2022-04-13</oef:PerfInceptionDate>
    <oef:UpdPerfInfoLocationTextBlock contextRef="C000235219_ClassMember" id="ixv-12116">&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="C000235219_ClassMember" id="ixv-12128">&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="C000235219_ClassMember" id="ixv-12132">&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="C000235219_ClassMember" id="ixv-12138">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;Key Fund Statistics&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(as of August 31, 2025)&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;$&lt;/span&gt;47,786,486&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;699&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;145,078&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;201&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="C000235219_InstantMember"
      decimals="0"
      id="ixv-225284"
      unitRef="usd">47786486</us-gaap:AssetsNet>
    <oef:HoldingsCount
      contextRef="C000235219_InstantMember"
      decimals="INF"
      id="ixv-225285"
      unitRef="holding">699</oef:HoldingsCount>
    <oef:AdvisoryFeesPaidAmt
      contextRef="C000235219_ClassMember"
      decimals="0"
      id="ixv-225286"
      unitRef="usd">145078</oef:AdvisoryFeesPaidAmt>
    <us-gaap:InvestmentCompanyPortfolioTurnover
      contextRef="C000235219_ClassMember"
      decimals="INF"
      id="ixv-225287"
      unitRef="pure">2.01</us-gaap:InvestmentCompanyPortfolioTurnover>
    <oef:HoldingsTableTextBlock contextRef="C000235219_ClassMember" id="ixv-12213">
&#160;
U.S. Government and U.S. Government Agency Obligations

55.1


AAA

5.8


AA

0.9


A

10.6


BBB

14.8


BB

4.2


B

2.5


CCC,CC,C

1.7


D

0.0


Not Rated

1.4


Equities

0.0


Short-Term Investments and Net Other Assets (Liabilities)

3.0




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

U.S. Government and U.S. Government Agency Obligations - 55.1


&#160;

AAA - 5.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

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


&#160;

A - 10.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BBB - 14.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BB - 4.2&#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;

B - 2.5&#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;


&#160;

CCC,CC,C - 1.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

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


&#160;

Not Rated - 1.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

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


&#160;

Short-Term Investments and Net Other Assets (Liabilities) - 3.0


&#160;


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




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

38.9


Corporate Bonds

33.0


U.S. Government Agency - Mortgage Securities

16.2


Asset-Backed Securities

6.0


CMOs and Other Mortgage Related Securities

0.9


Bank Loan Obligations

0.8


Foreign Government and Government Agency Obligations

0.8


Preferred Securities

0.4


Preferred Stocks

0.0


Common Stocks

0.0


Short-Term Investments and Net Other Assets (Liabilities)

3.0




ASSET ALLOCATION (% of Fund's net assets)


&#160;



&#160;

U.S. Treasury Obligations - 38.9&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Corporate Bonds - 33.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

U.S. Government Agency - Mortgage Securities - 16.2


&#160;

Asset-Backed Securities - 6.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

CMOs and Other Mortgage Related Securities - 0.9


&#160;

Bank Loan Obligations - 0.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Foreign Government and Government Agency Obligations - 0.8


&#160;

Preferred Securities - 0.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

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


&#160;

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


&#160;

Short-Term Investments and Net Other Assets (Liabilities) - 3.0


&#160;






United States

83.6


Grand Cayman (UK Overseas Ter)

3.9


United Kingdom

2.5


Bailiwick Of Jersey

1.6


Italy

1.4


France

0.8


Netherlands

0.7


Canada

0.7


Germany

0.6


Others

4.2




GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

United States - 83.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Grand Cayman (UK Overseas Ter) - 3.9&#160;&#160;&#160;&#160;


&#160;

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


&#160;

Bailiwick Of Jersey - 1.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Italy - 1.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

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


&#160;

Netherlands - 0.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Canada - 0.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Germany - 0.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Others - 4.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;




&#160;




&#160;
&#160;
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      id="ixv-225304"
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      id="ixv-225305"
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      id="ixv-225306"
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      decimals="INF"
      id="ixv-225307"
      unitRef="pure">0.004</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-225308"
      unitRef="pure">0.000</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-225309"
      unitRef="pure">0.000</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-225310"
      unitRef="pure">0.030</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235219_GD_US_Member"
      decimals="INF"
      id="ixv-225311"
      unitRef="pure">0.836</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-225312"
      unitRef="pure">0.039</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-225313"
      unitRef="pure">0.025</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235219_GD_BailiwickOfJersey_Member"
      decimals="INF"
      id="ixv-225314"
      unitRef="pure">0.016</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235219_GD_IT_Member"
      decimals="INF"
      id="ixv-225315"
      unitRef="pure">0.014</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235219_GD_FR_Member"
      decimals="INF"
      id="ixv-225316"
      unitRef="pure">0.008</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-225317"
      unitRef="pure">0.007</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235219_GD_CA_Member"
      decimals="INF"
      id="ixv-225318"
      unitRef="pure">0.007</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235219_GD_DE_Member"
      decimals="INF"
      id="ixv-225319"
      unitRef="pure">0.006</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-225320"
      unitRef="pure">0.042</oef:PctOfNav>
    <oef:LargestHoldingsTableTextBlock contextRef="C000235219_ClassMember" id="ixv-12739">TOP HOLDINGS(% of Fund's net assets)

&#160;

&#160;


US Treasury Notes

27.4


&#160;


US Treasury Bonds

11.5


&#160;


Fannie Mae Mortgage pass-thru certificates

5.0


&#160;


Ginnie Mae II Pool

4.1


&#160;


Uniform Mortgage Backed Securities

3.0


&#160;


Freddie Mac Gold Pool

2.8


&#160;


Bank of America Corp

1.1


&#160;


Symphony Clo Xxvi Ltd / Symphony Clo Xxvi LLC

1.0


&#160;


AES Corp/The

0.7


&#160;


Enel Finance International NV

0.7


&#160;


&#160;

57.3

&#160;



</oef:LargestHoldingsTableTextBlock>
    <oef:PctOfNav
      contextRef="C000235219_TH_0_Member"
      decimals="INF"
      id="ixv-225321"
      unitRef="pure">0.274</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235219_TH_1_Member"
      decimals="INF"
      id="ixv-225322"
      unitRef="pure">0.115</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235219_TH_2_Member"
      decimals="INF"
      id="ixv-225323"
      unitRef="pure">0.050</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235219_TH_3_Member"
      decimals="INF"
      id="ixv-225324"
      unitRef="pure">0.041</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235219_TH_4_Member"
      decimals="INF"
      id="ixv-225325"
      unitRef="pure">0.030</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235219_TH_5_Member"
      decimals="INF"
      id="ixv-225326"
      unitRef="pure">0.028</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235219_TH_6_Member"
      decimals="INF"
      id="ixv-225327"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235219_TH_7_Member"
      decimals="INF"
      id="ixv-225328"
      unitRef="pure">0.010</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235219_TH_8_Member"
      decimals="INF"
      id="ixv-225329"
      unitRef="pure">0.007</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235219_TH_9_Member"
      decimals="INF"
      id="ixv-225330"
      unitRef="pure">0.007</oef:PctOfNav>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-12910">2025-08-31</dei:DocumentPeriodEndDate>
    <oef:FundName contextRef="C000199795_ClassMember" id="ixv-12922">Fidelity&#xae; Sustainability Bond Index Fund</oef:FundName>
    <oef:ClassName contextRef="C000199795_ClassMember" id="ixv-12925">Fidelity&#xae; Sustainability Bond Index Fund</oef:ClassName>
    <dei:TradingSymbol contextRef="C000199795_ClassMember" id="ixv-12929">FNDSX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000199795_ClassMember" id="ixv-12948">This annual shareholder report contains information about Fidelity&#xae; Sustainability Bond Index Fund for the period September 1, 2024 to August 31, 2025.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000199795_ClassMember" id="ixv-12950">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000199795_ClassMember" id="ixv-12955">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="C000199795_ClassMember" id="ixv-12957">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000199795_ClassMember" id="ixv-12960">1-800-544-8544</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000199795_ClassMember" id="ixv-12963">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000199795_ClassMember" id="ixv-12970">&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:45%; 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:24%; 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:30%; 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 $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:45%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity&#xae; Sustainability Bond Index Fund&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:24%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$ &lt;/span&gt;10&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:30%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;0.10&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;/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="C000199795_ClassMember"
      decimals="0"
      id="ixv-225331"
      unitRef="usd">10</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000199795_ClassMember"
      decimals="INF"
      id="ixv-225332"
      unitRef="pure">0.0010</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000199795_ClassMember" id="ixv-13012">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What affected the Fund's performance this period?&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;U.S. taxable investment-grade bonds posted a solid advance for the 12 months ending August 31, 2025, navigating tariff-related uncertainty since late 2024 but buoyed by relatively stable consumer inflation, a resilient economy and the expectation of policy interest-rate cuts by the U.S. Federal Reserve in the second half of 2025.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity 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 that backdrop, we constructed the portfolio using optimization. This approach minimizes the differences between risk exposures of the fund relative to the index. We attempt to hold all positions held by the index in the same relative proportions.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Exposures include duration, key-rate durations and other factors.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:FactorsAffectingPerfTextBlock>
    <oef:LineGraphTableTextBlock contextRef="C000199795_ClassMember" id="ixv-13027">How did the Fund perform over the life of Fund?

 &#160;&#160;
CUMULATIVE PERFORMANCE
June 19, 2018 through August 31, 2025.
Initial investment of $10,000.
Fidelity&#xae; Sustainability Bond Index Fund


$10,000

$10,076


$11,088


$11,813


$11,746


$10,407


$10,280


$11,006



Bloomberg MSCI U.S. Aggregate ESG Choice Bond Index


$10,000

$10,090


$11,103


$11,834


$11,805


$10,466


$10,344


$11,096



Bloomberg U.S. Aggregate Bond Index


$10,000

$10,091


$11,117


$11,837


$11,827


$10,465


$10,340


$11,094



&#160;

2018

2019

2020

2021

2022

2023

2024

2025









&#160;
</oef:LineGraphTableTextBlock>
    <oef:LineGraphAndTableMeasureName contextRef="C000199795_LG_ClassMember_8YR" id="ixv-13046">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity&#xae; Sustainability Bond Index Fund&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000199795_ClassMember_AsOf_2018"
      decimals="0"
      id="ixv-225333"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000199795_ClassMember_AsOf_2019"
      decimals="0"
      id="ixv-225334"
      unitRef="usd">10076</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000199795_ClassMember_AsOf_2020"
      decimals="0"
      id="ixv-225335"
      unitRef="usd">11088</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000199795_ClassMember_AsOf_2021"
      decimals="0"
      id="ixv-225336"
      unitRef="usd">11813</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000199795_ClassMember_AsOf_2022"
      decimals="0"
      id="ixv-225337"
      unitRef="usd">11746</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000199795_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-225338"
      unitRef="usd">10407</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000199795_ClassMember_AsOf_2024"
      decimals="0"
      id="ixv-225339"
      unitRef="usd">10280</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000199795_ClassMember_AsOf_2025"
      decimals="0"
      id="ixv-225340"
      unitRef="usd">11006</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000199795_LG_1_AdditionalIndexMember_8YR"
      id="ixv-13083">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg MSCI U.S. Aggregate ESG Choice Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000199795_1_AdditionalIndexMember_AsOf_2018"
      decimals="0"
      id="ixv-225341"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000199795_1_AdditionalIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-225342"
      unitRef="usd">10090</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000199795_1_AdditionalIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-225343"
      unitRef="usd">11103</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000199795_1_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-225344"
      unitRef="usd">11834</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000199795_1_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-225345"
      unitRef="usd">11805</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000199795_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-225346"
      unitRef="usd">10466</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000199795_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-225347"
      unitRef="usd">10344</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000199795_1_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-225348"
      unitRef="usd">11096</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000199795_LG_2_AdditionalIndexMember_8YR"
      id="ixv-13120">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg U.S. Aggregate Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000199795_2_AdditionalIndexMember_AsOf_2018"
      decimals="0"
      id="ixv-225349"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000199795_2_AdditionalIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-225350"
      unitRef="usd">10091</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000199795_2_AdditionalIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-225351"
      unitRef="usd">11117</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000199795_2_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-225352"
      unitRef="usd">11837</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000199795_2_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-225353"
      unitRef="usd">11827</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000199795_2_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-225354"
      unitRef="usd">10465</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000199795_2_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-225355"
      unitRef="usd">10340</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000199795_2_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-225356"
      unitRef="usd">11094</oef:AccmVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000199795_ClassMember" id="ixv-13200">AVERAGE ANNUAL TOTAL RETURNS:

&#160;

1 Year

5 Year

Life of Fund&#160;A


Fidelity&#xae; Sustainability Bond Index Fund

3.11%

-0.80%

1.77%


Bloomberg MSCI U.S. Aggregate ESG Choice Bond Index

3.17%


-0.66%


1.89%


Bloomberg U.S. Aggregate Bond Index

3.14%


-0.68%


1.89%




A&#160; &#160;From June 19, 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="C000199795_NoLoadClassMember_1YR"
      decimals="INF"
      id="ixv-225357"
      unitRef="pure">0.0311</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000199795_NoLoadClassMember_5YR"
      decimals="INF"
      id="ixv-225358"
      unitRef="pure">-0.0080</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000199795_NoLoadClassMember_2024-09-01_2025-08-31"
      decimals="INF"
      id="ixv-225359"
      unitRef="pure">0.0177</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000199795_0_AdditionalIndexMember_1YR"
      decimals="INF"
      id="ixv-225360"
      unitRef="pure">0.0317</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000199795_0_AdditionalIndexMember_5YR"
      decimals="INF"
      id="ixv-225361"
      unitRef="pure">-0.0066</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000199795_0_AdditionalIndexMember_LOC"
      decimals="INF"
      id="ixv-225362"
      unitRef="pure">0.0189</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000199795_1_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-225363"
      unitRef="pure">0.0314</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000199795_1_BBIndexMember_5YR"
      decimals="INF"
      id="ixv-225364"
      unitRef="pure">-0.0068</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000199795_1_BBIndexMember_LOC"
      decimals="INF"
      id="ixv-225365"
      unitRef="pure">0.0189</oef:AvgAnnlRtrPct>
    <oef:PerfInceptionDate
      contextRef="C000199795_Perf_2018-06-19_ClassMember"
      id="ixv-13272">2018-06-19</oef:PerfInceptionDate>
    <oef:UpdPerfInfoLocationTextBlock contextRef="C000199795_ClassMember" id="ixv-13282">&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="C000199795_ClassMember" id="ixv-13294">&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="C000199795_ClassMember" id="ixv-13298">&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="C000199795_ClassMember" id="ixv-13304">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;Key Fund Statistics&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(as of August 31, 2025)&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;$&lt;/span&gt;588,693,470&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;3,087&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;514,470&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
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      decimals="0"
      id="ixv-225366"
      unitRef="usd">588693470</us-gaap:AssetsNet>
    <oef:HoldingsCount
      contextRef="C000199795_InstantMember"
      decimals="INF"
      id="ixv-225367"
      unitRef="holding">3087</oef:HoldingsCount>
    <oef:AdvisoryFeesPaidAmt
      contextRef="C000199795_ClassMember"
      decimals="0"
      id="ixv-225368"
      unitRef="usd">514470</oef:AdvisoryFeesPaidAmt>
    <us-gaap:InvestmentCompanyPortfolioTurnover
      contextRef="C000199795_ClassMember"
      decimals="INF"
      id="ixv-225369"
      unitRef="pure">0.70</us-gaap:InvestmentCompanyPortfolioTurnover>
    <oef:HoldingsTableTextBlock contextRef="C000199795_ClassMember" id="ixv-13379">
&#160;
U.S. Government and U.S. Government Agency Obligations

69.3


AAA

3.0


AA

2.3


A

12.8


BBB

11.3


BB

0.4


Not Rated

0.3


Short-Term Investments and Net Other Assets (Liabilities)

0.6




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

U.S. Government and U.S. Government Agency Obligations - 69.3


&#160;

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


&#160;

AA - 2.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

A - 12.8&#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 - 11.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

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


&#160;

Not Rated - 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;

Short-Term Investments and Net Other Assets (Liabilities) - 0.6


&#160;


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




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

45.1


Corporate Bonds

26.8


U.S. Government Agency - Mortgage Securities

24.1


Foreign Government and Government Agency Obligations

1.9


CMOs and Other Mortgage Related Securities

1.1


Asset-Backed Securities

0.3


U.S. Government Agency Obligations

0.1


Other Investments

0.0


Short-Term Investments and Net Other Assets (Liabilities)

0.6




ASSET ALLOCATION (% of Fund's net assets)


&#160;



&#160;

U.S. Treasury Obligations - 45.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Corporate Bonds - 26.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

U.S. Government Agency - Mortgage Securities - 24.1


&#160;

Foreign Government and Government Agency Obligations - 1.9


&#160;

CMOs and Other Mortgage Related Securities - 1.1


&#160;

Asset-Backed Securities - 0.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

U.S. Government Agency Obligations - 0.1


&#160;

Other Investments - 0.0&#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) - 0.6


&#160;






United States

92.4


United Kingdom

1.5


Canada

1.1


Multi-national

1.0


Japan

0.8


Mexico

0.5


Germany

0.4


Spain

0.2


Australia

0.2


Others

1.9




GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

United States - 92.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

United Kingdom - 1.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

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


&#160;

Multi-national - 1.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Japan - 0.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Mexico - 0.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Germany - 0.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Spain - 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;

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;

Others - 1.9&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;




&#160;




&#160;
&#160;
</oef:HoldingsTableTextBlock>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-225370"
      unitRef="pure">0.693</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000199795_QD_AAA_Member"
      decimals="INF"
      id="ixv-225371"
      unitRef="pure">0.030</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000199795_QD_AA_Member"
      decimals="INF"
      id="ixv-225372"
      unitRef="pure">0.023</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000199795_QD_A_Member"
      decimals="INF"
      id="ixv-225373"
      unitRef="pure">0.128</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000199795_QD_BBB_Member"
      decimals="INF"
      id="ixv-225374"
      unitRef="pure">0.113</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000199795_QD_BB_Member"
      decimals="INF"
      id="ixv-225375"
      unitRef="pure">0.004</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000199795_QD_NotRated_Member"
      decimals="INF"
      id="ixv-225376"
      unitRef="pure">0.003</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-225377"
      unitRef="pure">0.006</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000199795_AA_USTreasuryObligations_Member"
      decimals="INF"
      id="ixv-225378"
      unitRef="pure">0.451</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000199795_AA_CorporateBonds_Member"
      decimals="INF"
      id="ixv-225379"
      unitRef="pure">0.268</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000199795_AA_USGovernmentAgencyMortgageSecurities_Member"
      decimals="INF"
      id="ixv-225380"
      unitRef="pure">0.241</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000199795_AA_ForeignGovernmentandGovernmentAgencyObligations_Member"
      decimals="INF"
      id="ixv-225381"
      unitRef="pure">0.019</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000199795_AA_CMOsandOtherMortgageRelatedSecurities_Member"
      decimals="INF"
      id="ixv-225382"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000199795_AA_AssetBackedSecurities_Member"
      decimals="INF"
      id="ixv-225383"
      unitRef="pure">0.003</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000199795_AA_USGovernmentAgencyObligations_Member"
      decimals="INF"
      id="ixv-225384"
      unitRef="pure">0.001</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000199795_AA_OtherInvestments_Member"
      decimals="INF"
      id="ixv-225385"
      unitRef="pure">0.000</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000199795_AA_ShortTermInvestmentsandNetOtherAssetsLiabilities_Member"
      decimals="INF"
      id="ixv-225386"
      unitRef="pure">0.006</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000199795_GD_US_Member"
      decimals="INF"
      id="ixv-225387"
      unitRef="pure">0.924</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000199795_GD_GB_Member"
      decimals="INF"
      id="ixv-225388"
      unitRef="pure">0.015</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000199795_GD_CA_Member"
      decimals="INF"
      id="ixv-225389"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000199795_GD_Multinational_Member"
      decimals="INF"
      id="ixv-225390"
      unitRef="pure">0.010</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000199795_GD_JP_Member"
      decimals="INF"
      id="ixv-225391"
      unitRef="pure">0.008</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000199795_GD_MX_Member"
      decimals="INF"
      id="ixv-225392"
      unitRef="pure">0.005</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000199795_GD_DE_Member"
      decimals="INF"
      id="ixv-225393"
      unitRef="pure">0.004</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000199795_GD_ES_Member"
      decimals="INF"
      id="ixv-225394"
      unitRef="pure">0.002</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000199795_GD_AU_Member"
      decimals="INF"
      id="ixv-225395"
      unitRef="pure">0.002</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000199795_GD_Other_Member"
      decimals="INF"
      id="ixv-225396"
      unitRef="pure">0.019</oef:PctOfNav>
    <oef:LargestHoldingsTableTextBlock contextRef="C000199795_ClassMember" id="ixv-13827">TOP HOLDINGS(% of Fund's net assets)

&#160;

&#160;


US Treasury Notes

35.8


&#160;


US Treasury Bonds

9.3


&#160;


Fannie Mae Mortgage pass-thru certificates

9.3


&#160;


Freddie Mac Gold Pool

7.8


&#160;


Ginnie Mae II Pool

4.6


&#160;


Uniform Mortgage Backed Securities

1.1


&#160;


Ginnie Mae I Pool

0.9


&#160;


Bank of America Corp

0.8


&#160;


JPMorgan Chase &amp; Co

0.7


&#160;


HSBC Holdings PLC

0.6


&#160;


&#160;

70.9

&#160;



</oef:LargestHoldingsTableTextBlock>
    <oef:PctOfNav
      contextRef="C000199795_TH_0_Member"
      decimals="INF"
      id="ixv-225397"
      unitRef="pure">0.358</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000199795_TH_1_Member"
      decimals="INF"
      id="ixv-225398"
      unitRef="pure">0.093</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000199795_TH_2_Member"
      decimals="INF"
      id="ixv-225399"
      unitRef="pure">0.093</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000199795_TH_3_Member"
      decimals="INF"
      id="ixv-225400"
      unitRef="pure">0.078</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000199795_TH_4_Member"
      decimals="INF"
      id="ixv-225401"
      unitRef="pure">0.046</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000199795_TH_5_Member"
      decimals="INF"
      id="ixv-225402"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000199795_TH_6_Member"
      decimals="INF"
      id="ixv-225403"
      unitRef="pure">0.009</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000199795_TH_7_Member"
      decimals="INF"
      id="ixv-225404"
      unitRef="pure">0.008</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000199795_TH_8_Member"
      decimals="INF"
      id="ixv-225405"
      unitRef="pure">0.007</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000199795_TH_9_Member"
      decimals="INF"
      id="ixv-225406"
      unitRef="pure">0.006</oef:PctOfNav>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-13998">2025-08-31</dei:DocumentPeriodEndDate>
    <oef:FundName contextRef="C000194645_ClassMember" id="ixv-14010">Fidelity&#xae; Short-Term Bond Index Fund</oef:FundName>
    <oef:ClassName contextRef="C000194645_ClassMember" id="ixv-14013">Fidelity&#xae; Short-Term Bond Index Fund</oef:ClassName>
    <dei:TradingSymbol contextRef="C000194645_ClassMember" id="ixv-14017">FNSOX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000194645_ClassMember" id="ixv-14036">This annual shareholder report contains information about Fidelity&#xae; Short-Term Bond Index Fund for the period September 1, 2024 to August 31, 2025.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000194645_ClassMember" id="ixv-14038">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000194645_ClassMember" id="ixv-14043">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="C000194645_ClassMember" id="ixv-14045">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000194645_ClassMember" id="ixv-14048">1-800-544-8544</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000194645_ClassMember" id="ixv-14051">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000194645_ClassMember" id="ixv-14058">&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:45%; 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:24%; 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:30%; 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 $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:45%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity&#xae; Short-Term Bond Index Fund&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:24%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$ &lt;/span&gt;3&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:30%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;0.03&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="C000194645_ClassMember"
      decimals="0"
      id="ixv-225407"
      unitRef="usd">3</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000194645_ClassMember"
      decimals="INF"
      id="ixv-225408"
      unitRef="pure">0.0003</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000194645_ClassMember" id="ixv-14100">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What affected the Fund's performance this period?&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;U.S. taxable investment-grade bonds posted a solid advance for the 12 months ending August 31, 2025, driven early on by the Federal Reserve's pivot to cutting interest rates from September through December 2024 and late in the period by expectations that the central bank would resume rate cuts in September 2025.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity 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 that backdrop, we constructed the portfolio using optimization. This approach minimizes the differences between risk exposures of the fund relative to the index. We attempt to hold all positions held by the index in the same relative proportions.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Exposures include duration, key-rate durations and other factors,&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:FactorsAffectingPerfTextBlock>
    <oef:LineGraphTableTextBlock contextRef="C000194645_ClassMember" id="ixv-14115">How did the Fund perform over the life of Fund?

 &#160;&#160;
CUMULATIVE PERFORMANCE
October 18, 2017 through August 31, 2025.
Initial investment of $10,000.
Fidelity&#xae; Short-Term Bond Index Fund


$10,000

$9,969


$10,565


$11,052


$11,073


$10,427


$10,551


$11,255


$11,789



Bloomberg U.S. 1-5 Year Government/Credit Bond Index


$10,000

$9,990


$10,586


$11,086


$11,122


$10,472


$10,596


$11,303


$11,844



Bloomberg U.S. Aggregate Bond Index


$10,000

$9,938


$10,949


$11,658


$11,648


$10,307


$10,184


$10,927


$11,269



&#160;

2017

2018

2019

2020

2021

2022

2023

2024

2025









&#160;
</oef:LineGraphTableTextBlock>
    <oef:LineGraphAndTableMeasureName contextRef="C000194645_LG_ClassMember_9YR" id="ixv-14134">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity&#xae; Short-Term Bond Index Fund&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000194645_ClassMember_AsOf_2017"
      decimals="0"
      id="ixv-225409"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000194645_ClassMember_AsOf_2018"
      decimals="0"
      id="ixv-225410"
      unitRef="usd">9969</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000194645_ClassMember_AsOf_2019"
      decimals="0"
      id="ixv-225411"
      unitRef="usd">10565</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000194645_ClassMember_AsOf_2020"
      decimals="0"
      id="ixv-225412"
      unitRef="usd">11052</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000194645_ClassMember_AsOf_2021"
      decimals="0"
      id="ixv-225413"
      unitRef="usd">11073</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000194645_ClassMember_AsOf_2022"
      decimals="0"
      id="ixv-225414"
      unitRef="usd">10427</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000194645_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-225415"
      unitRef="usd">10551</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000194645_ClassMember_AsOf_2024"
      decimals="0"
      id="ixv-225416"
      unitRef="usd">11255</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000194645_ClassMember_AsOf_2025"
      decimals="0"
      id="ixv-225417"
      unitRef="usd">11789</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000194645_LG_1_AdditionalIndexMember_9YR"
      id="ixv-14175">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg U.S. 1-5 Year Government/Credit Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000194645_1_AdditionalIndexMember_AsOf_2017"
      decimals="0"
      id="ixv-225418"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000194645_1_AdditionalIndexMember_AsOf_2018"
      decimals="0"
      id="ixv-225419"
      unitRef="usd">9990</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000194645_1_AdditionalIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-225420"
      unitRef="usd">10586</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000194645_1_AdditionalIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-225421"
      unitRef="usd">11086</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000194645_1_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-225422"
      unitRef="usd">11122</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000194645_1_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-225423"
      unitRef="usd">10472</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000194645_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-225424"
      unitRef="usd">10596</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000194645_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-225425"
      unitRef="usd">11303</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000194645_1_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-225426"
      unitRef="usd">11844</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000194645_LG_2_AdditionalIndexMember_9YR"
      id="ixv-14216">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg U.S. Aggregate Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000194645_2_AdditionalIndexMember_AsOf_2017"
      decimals="0"
      id="ixv-225427"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000194645_2_AdditionalIndexMember_AsOf_2018"
      decimals="0"
      id="ixv-225428"
      unitRef="usd">9938</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000194645_2_AdditionalIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-225429"
      unitRef="usd">10949</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000194645_2_AdditionalIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-225430"
      unitRef="usd">11658</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000194645_2_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-225431"
      unitRef="usd">11648</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000194645_2_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-225432"
      unitRef="usd">10307</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000194645_2_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-225433"
      unitRef="usd">10184</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000194645_2_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-225434"
      unitRef="usd">10927</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000194645_2_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-225435"
      unitRef="usd">11269</oef:AccmVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000194645_ClassMember" id="ixv-14303">AVERAGE ANNUAL TOTAL RETURNS:

&#160;

1 Year

5 Year

Life of Fund&#160;A


Fidelity&#xae; Short-Term Bond Index Fund

4.74%

1.30%

2.11%


Bloomberg U.S. 1-5 Year Government/Credit Bond Index

4.79%


1.33%


2.17%


Bloomberg U.S. Aggregate Bond Index

3.14%


-0.68%


1.53%




A&#160; &#160;From October 18, 2017

&#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="C000194645_NoLoadClassMember_1YR"
      decimals="INF"
      id="ixv-225436"
      unitRef="pure">0.0474</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000194645_NoLoadClassMember_5YR"
      decimals="INF"
      id="ixv-225437"
      unitRef="pure">0.0130</oef:AvgAnnlRtrPct>
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      decimals="INF"
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      contextRef="C000194645_Perf_2017-10-18_ClassMember"
      id="ixv-14373">2017-10-18</oef:PerfInceptionDate>
    <oef:UpdPerfInfoLocationTextBlock contextRef="C000194645_ClassMember" id="ixv-14383">&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="C000194645_ClassMember" id="ixv-14395">&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="C000194645_ClassMember" id="ixv-14399">&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="C000194645_ClassMember" id="ixv-14405">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;Key Fund Statistics&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(as of August 31, 2025)&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;$&lt;/span&gt;3,356,675,729&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;1,403&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;941,088&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;55&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>
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    <oef:HoldingsTableTextBlock contextRef="C000194645_ClassMember" id="ixv-14480">
&#160;
U.S. Government and U.S. Government Agency Obligations

69.8


AAA

1.7


AA

2.9


A

13.1


BBB

11.6


BB

0.4


Short-Term Investments and Net Other Assets (Liabilities)

0.5




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

U.S. Government and U.S. Government Agency Obligations - 69.8


&#160;

AAA - 1.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

AA - 2.9&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

A - 13.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BBB - 11.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

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


&#160;

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


&#160;


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




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

69.5


Corporate Bonds

28.3


Foreign Government and Government Agency Obligations

0.9


Other Investments

0.5


U.S. Government Agency Obligations

0.3


Short-Term Investments and Net Other Assets (Liabilities)

0.5




ASSET ALLOCATION (% of Fund's net assets)


&#160;



&#160;

U.S. Treasury Obligations - 69.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Corporate Bonds - 28.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Foreign Government and Government Agency Obligations - 0.9


&#160;

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


&#160;

U.S. Government Agency Obligations - 0.3


&#160;

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


&#160;






United States

92.6


Canada

1.6


United Kingdom

1.4


Japan

1.2


Multi-national

0.8


Germany

0.7


Spain

0.3


Australia

0.3


Korea (South)

0.2


Others

0.9




GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

United States - 92.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Canada - 1.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

United Kingdom - 1.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Japan - 1.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Multi-national - 0.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

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


&#160;

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


&#160;

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


&#160;

Korea (South) - 0.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

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




&#160;




&#160;
&#160;
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    <oef:LargestHoldingsTableTextBlock contextRef="C000194645_ClassMember" id="ixv-14876">TOP HOLDINGS(% of Fund's net assets)

&#160;

&#160;


US Treasury Notes

69.5


&#160;


JPMorgan Chase &amp; Co

0.9


&#160;


Bank of America Corp

0.7


&#160;


Morgan Stanley

0.7


&#160;


Goldman Sachs Group Inc/The

0.7


&#160;


Wells Fargo &amp; Co

0.6


&#160;


HSBC Holdings PLC

0.5


&#160;


Citigroup Inc

0.4


&#160;


KfW

0.4


&#160;


Barclays PLC

0.4


&#160;


&#160;

74.8

&#160;



</oef:LargestHoldingsTableTextBlock>
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    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-15047">2025-08-31</dei:DocumentPeriodEndDate>
    <oef:FundName contextRef="C000242612_ClassMember" id="ixv-15059">Fidelity&#xae; Series Sustainable Investment Grade Bond Fund</oef:FundName>
    <oef:ClassName contextRef="C000242612_ClassMember" id="ixv-15062">Fidelity&#xae; Series Sustainable Investment Grade Bond Fund</oef:ClassName>
    <dei:TradingSymbol contextRef="C000242612_ClassMember" id="ixv-15066">FIGDX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000242612_ClassMember" id="ixv-15085">This annual shareholder report contains information about Fidelity&#xae; Series Sustainable Investment Grade Bond Fund for the period September 1, 2024 to August 31, 2025.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000242612_ClassMember" id="ixv-15087">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000242612_ClassMember" id="ixv-15092">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="C000242612_ClassMember" id="ixv-15094">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000242612_ClassMember" id="ixv-15097">1-800-544-8544</oef:AddlInfoPhoneNumber>
    <oef:ExpensesTextBlock contextRef="C000242612_ClassMember" id="ixv-15104">&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:45%; 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:24%; 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:30%; 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 $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:45%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity&#xae; Series Sustainable Investment Grade Bond Fund&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:24%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$ &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:30%; 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="C000242612_ClassMember"
      decimals="0"
      id="ixv-225482"
      unitRef="usd">0</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000242612_ClassMember"
      decimals="INF"
      id="ixv-225483"
      unitRef="pure">0.0000</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000242612_ClassMember" id="ixv-15156">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What affected the Fund's performance this period?&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;U.S. taxable investment-grade bonds posted a solid advance for the 12 months ending August 31, 2025, navigating tariff-related uncertainty since late 2024 but buoyed by relatively stable consumer inflation, a resilient economy and the expectation of policy interest-rate cuts by the U.S. Federal Reserve in the second half of 2025.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Against this backdrop, security selection contributed to the fund's outperformance of the Bloomberg U.S. Aggregate Bond Index for the fiscal year.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Specifically, fund holdings in the corporate segment made a notable contribution to relative performance, led by picks among financials, particularly REITs and banks.&#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 and picks among collateralized loan obligations also helped.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;The fund's underweights in mortgage-backed securities and U.S. Treasurys buoyed relative performance as well.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;The portfolio's yield-curve positioning also provided a boost to performance versus the benchmark.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;In contrast, the fund's underweight in the bonds of industrial firms within the corporate sector detracted versus the benchmark.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;The fund's modestly longer duration relative to the benchmark 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;Notable changes over the past 12 months included management's decision to gradually lower the fund's overall risk profile by reducing exposure to investment-grade corporate bonds and increasing the allocation to U.S. Treasurys.&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="C000242612_ClassMember" id="ixv-15196">How did the Fund perform over the life of Fund?

 &#160;&#160;
CUMULATIVE PERFORMANCE
May 11, 2023 through August 31, 2025.
Initial investment of $10,000.
Fidelity&#xae; Series Sustainable Investment Grade Bond Fund


$10,000

$9,778


$10,503



Bloomberg MSCI U.S. Aggregate ESG Choice Bond Index


$10,000

$9,772


$10,481



Bloomberg U.S. Aggregate Bond Index


$10,000

$9,768


$10,480



&#160;

2023

2024

2025









&#160;
</oef:LineGraphTableTextBlock>
    <oef:LineGraphAndTableMeasureName contextRef="C000242612_LG_ClassMember_3YR" id="ixv-15215">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity&#xae; Series Sustainable Investment Grade Bond Fund&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000242612_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-225484"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000242612_ClassMember_AsOf_2024"
      decimals="0"
      id="ixv-225485"
      unitRef="usd">9778</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000242612_ClassMember_AsOf_2025"
      decimals="0"
      id="ixv-225486"
      unitRef="usd">10503</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000242612_LG_1_AdditionalIndexMember_3YR"
      id="ixv-15232">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg MSCI U.S. Aggregate ESG Choice Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000242612_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-225487"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000242612_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-225488"
      unitRef="usd">9772</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000242612_1_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-225489"
      unitRef="usd">10481</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000242612_LG_2_AdditionalIndexMember_3YR"
      id="ixv-15249">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg U.S. Aggregate Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000242612_2_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-225490"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000242612_2_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-225491"
      unitRef="usd">9768</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000242612_2_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-225492"
      unitRef="usd">10480</oef:AccmVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000242612_ClassMember" id="ixv-15294">AVERAGE ANNUAL TOTAL RETURNS:

&#160;

1 Year

Life of Fund&#160;A


Fidelity&#xae; Series Sustainable Investment Grade Bond Fund

3.25%

3.57%


Bloomberg MSCI U.S. Aggregate ESG Choice Bond Index

3.17%


3.45%


Bloomberg U.S. Aggregate Bond Index

3.14%


3.43%




A&#160; &#160;From May 11, 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
      contextRef="C000242612_NoLoadClassMember_1YR"
      decimals="INF"
      id="ixv-225493"
      unitRef="pure">0.0325</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000242612_NoLoadClassMember_2024-09-01_2025-08-31"
      decimals="INF"
      id="ixv-225494"
      unitRef="pure">0.0357</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000242612_0_AdditionalIndexMember_1YR"
      decimals="INF"
      id="ixv-225495"
      unitRef="pure">0.0317</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000242612_0_AdditionalIndexMember_LOC"
      decimals="INF"
      id="ixv-225496"
      unitRef="pure">0.0345</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000242612_1_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-225497"
      unitRef="pure">0.0314</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000242612_1_BBIndexMember_LOC"
      decimals="INF"
      id="ixv-225498"
      unitRef="pure">0.0343</oef:AvgAnnlRtrPct>
    <oef:PerfInceptionDate
      contextRef="C000242612_Perf_2023-05-11_ClassMember"
      id="ixv-15349">2023-05-11</oef:PerfInceptionDate>
    <oef:UpdPerfInfoLocationTextBlock contextRef="C000242612_ClassMember" id="ixv-15359">&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="C000242612_ClassMember" id="ixv-15371">&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="C000242612_ClassMember" id="ixv-15375">&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="C000242612_ClassMember" id="ixv-15381">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;Key Fund Statistics&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(as of August 31, 2025)&lt;/span&gt;&lt;/div&gt;
&lt;div&gt;&lt;span style="font-size:11px;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;table cellpadding="0" cellspacing="1" style="border-collapse:separate;border-style:none;margin:auto;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:63%; " valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:bold;"&gt;KEY FACTS&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt; &lt;span&gt;&#160;&lt;/span&gt;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fund Size&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;11,708,507&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;177&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&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;235&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>
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&#160;
U.S. Government and U.S. Government Agency Obligations

69.3


AAA

4.4


AA

0.6


A

9.1


BBB

9.5


BB

0.8


Not Rated

2.2


Short-Term Investments and Net Other Assets (Liabilities)

4.1




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

U.S. Government and U.S. Government Agency Obligations - 69.3


&#160;

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


&#160;

AA - 0.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

A - 9.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BBB - 9.5&#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 - 0.8&#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;

Not Rated - 2.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

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


&#160;


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




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

52.7


Corporate Bonds

19.6


U.S. Government Agency - Mortgage Securities

16.6


Asset-Backed Securities

6.4


Foreign Government and Government Agency Obligations

0.4


CMOs and Other Mortgage Related Securities

0.2


Short-Term Investments and Net Other Assets (Liabilities)

4.1




ASSET ALLOCATION (% of Fund's net assets)


&#160;



&#160;

U.S. Treasury Obligations - 52.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Corporate Bonds - 19.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

U.S. Government Agency - Mortgage Securities - 16.6


&#160;

Asset-Backed Securities - 6.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Foreign Government and Government Agency Obligations - 0.4


&#160;

CMOs and Other Mortgage Related Securities - 0.2


&#160;

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


&#160;






United States

92.2


Grand Cayman (UK Overseas Ter)

6.4


Canada

0.5


Mexico

0.4


Netherlands

0.3


United Kingdom

0.2




GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

United States - 92.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Grand Cayman (UK Overseas Ter) - 6.4&#160;&#160;&#160;&#160;


&#160;

Canada - 0.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Mexico - 0.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Netherlands - 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;

United Kingdom - 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;
</oef:HoldingsTableTextBlock>
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    <oef:PctOfNav
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    <oef:PctOfNav
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      unitRef="pure">0.196</oef:PctOfNav>
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      decimals="INF"
      id="ixv-225513"
      unitRef="pure">0.166</oef:PctOfNav>
    <oef:PctOfNav
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      id="ixv-225514"
      unitRef="pure">0.064</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-225515"
      unitRef="pure">0.004</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000242612_AA_CMOsandOtherMortgageRelatedSecurities_Member"
      decimals="INF"
      id="ixv-225516"
      unitRef="pure">0.002</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000242612_AA_ShortTermInvestmentsandNetOtherAssetsLiabilities_Member"
      decimals="INF"
      id="ixv-225517"
      unitRef="pure">0.041</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000242612_GD_US_Member"
      decimals="INF"
      id="ixv-225518"
      unitRef="pure">0.922</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000242612_GD_GrandCaymanUKOverseasTer_Member"
      decimals="INF"
      id="ixv-225519"
      unitRef="pure">0.064</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000242612_GD_CA_Member"
      decimals="INF"
      id="ixv-225520"
      unitRef="pure">0.005</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000242612_GD_MX_Member"
      decimals="INF"
      id="ixv-225521"
      unitRef="pure">0.004</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000242612_GD_NL_Member"
      decimals="INF"
      id="ixv-225522"
      unitRef="pure">0.003</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000242612_GD_GB_Member"
      decimals="INF"
      id="ixv-225523"
      unitRef="pure">0.002</oef:PctOfNav>
    <oef:LargestHoldingsTableTextBlock contextRef="C000242612_ClassMember" id="ixv-15826">TOP HOLDINGS(% of Fund's net assets)

&#160;

&#160;


US Treasury Notes

40.7


&#160;


US Treasury Bonds

12.0


&#160;


Uniform Mortgage Backed Securities

6.9


&#160;


Ginnie Mae II Pool

4.0


&#160;


Fannie Mae Mortgage pass-thru certificates

2.5


&#160;


Allegro Clo Xii Ltd

2.2


&#160;


RR 28 LTD / RR 28 LLC

2.1


&#160;


Magnetite Xxvi Ltd / Magnetite Xxvi LLC

2.1


&#160;


Freddie Mac Gold Pool

1.8


&#160;


JPMorgan Chase &amp; Co

1.2


&#160;


&#160;

75.5

&#160;



</oef:LargestHoldingsTableTextBlock>
    <oef:PctOfNav
      contextRef="C000242612_TH_0_Member"
      decimals="INF"
      id="ixv-225524"
      unitRef="pure">0.407</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000242612_TH_1_Member"
      decimals="INF"
      id="ixv-225525"
      unitRef="pure">0.120</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000242612_TH_2_Member"
      decimals="INF"
      id="ixv-225526"
      unitRef="pure">0.069</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000242612_TH_3_Member"
      decimals="INF"
      id="ixv-225527"
      unitRef="pure">0.040</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000242612_TH_4_Member"
      decimals="INF"
      id="ixv-225528"
      unitRef="pure">0.025</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000242612_TH_5_Member"
      decimals="INF"
      id="ixv-225529"
      unitRef="pure">0.022</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000242612_TH_6_Member"
      decimals="INF"
      id="ixv-225530"
      unitRef="pure">0.021</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000242612_TH_7_Member"
      decimals="INF"
      id="ixv-225531"
      unitRef="pure">0.021</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000242612_TH_8_Member"
      decimals="INF"
      id="ixv-225532"
      unitRef="pure">0.018</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000242612_TH_9_Member"
      decimals="INF"
      id="ixv-225533"
      unitRef="pure">0.012</oef:PctOfNav>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-15997">2025-08-31</dei:DocumentPeriodEndDate>
    <oef:FundName contextRef="C000203456_ClassMember" id="ixv-16009">Fidelity&#xae; Series Corporate Bond Fund</oef:FundName>
    <oef:ClassName contextRef="C000203456_ClassMember" id="ixv-16012">Fidelity&#xae; Series Corporate Bond Fund</oef:ClassName>
    <dei:TradingSymbol contextRef="C000203456_ClassMember" id="ixv-16016">FHMFX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000203456_ClassMember" id="ixv-16035">This annual shareholder report contains information about Fidelity&#xae; Series Corporate Bond Fund for the period September 1, 2024 to August 31, 2025.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000203456_ClassMember" id="ixv-16037">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000203456_ClassMember" id="ixv-16042">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="C000203456_ClassMember" id="ixv-16044">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000203456_ClassMember" id="ixv-16047">1-800-544-8544</oef:AddlInfoPhoneNumber>
    <oef:ExpensesTextBlock contextRef="C000203456_ClassMember" id="ixv-16054">&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:45%; 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:24%; 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:30%; 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 $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:45%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity&#xae; Series Corporate Bond Fund&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:24%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$ &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:30%; 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>
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      unitRef="usd">0</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
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      decimals="INF"
      id="ixv-225535"
      unitRef="pure">0.0000</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000203456_ClassMember" id="ixv-16106">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What affected the Fund's performance this period?&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;U.S. taxable investment-grade bonds posted a solid advance for the 12 months ending August 31, 2025, navigating tariff-related uncertainty since late 2024 but buoyed by relatively stable consumer inflation, a resilient economy and the expectation of policy interest-rate cuts by the U.S. Federal Reserve in the second half of 2025.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Against this backdrop, security selection contributed to the fund's performance versus the benchmark Bloomberg U.S. Credit Bond Index for the fiscal year, whereas sector positioning detracted.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Bond picks among companies in the industrials sector helped most, led by issuers in the communications, consumer non-cyclicals and capital goods industries.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Within communications, notable contributors included Warner Bros. Discovery and Charter Communications. In consumer non-cyclicals, pharmaceutical company Bayer was a standout, while Boeing drove the contribution in capital goods.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Picks among financial issuers also notably aided relative performance. Here, bonds from banks, real estate investment trusts and insurance companies helped most.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Outside of corporate credit, an allocation to U.S. Treasurys and cash - held for liquidity and risk-management purposes - meaningfully detracted from the fund's relative result. This negative was somewhat offset by steering clear of other government-related categories, as these bonds lagged credit in an improving market environment.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity 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 strategy of concentrating the portfolio's holdings in the five- to seven-year portion of the curve slightly dampened 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 period, the fund's managers continued to emphasize issuers rated BBB, as they believe there is opportunity for alpha potential over time resulting from improving credit quality. They modestly added bonds rated A, in response to tight spreads and uncertainty.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Noteworthy positioning changes included reducing exposure to non-bank financials (e.g., finance companies) and redeploying the capital into industrials and utilities.&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="C000203456_ClassMember" id="ixv-16139">How did the Fund perform over the life of Fund?

 &#160;&#160;
CUMULATIVE PERFORMANCE
August 17, 2018 through August 31, 2025.
Initial investment of $10,000.
Fidelity&#xae; Series Corporate Bond Fund


$10,000

$9,963


$11,296


$12,221


$12,610


$10,698


$10,807


$11,903



Bloomberg U.S. Credit Bond Index


$10,000

$10,005


$11,305


$12,107


$12,381


$10,594


$10,684


$11,644



Bloomberg U.S. Aggregate Bond Index


$10,000

$10,014


$11,033


$11,747


$11,737


$10,386


$10,262


$11,010



&#160;

2018

2019

2020

2021

2022

2023

2024

2025









&#160;
</oef:LineGraphTableTextBlock>
    <oef:LineGraphAndTableMeasureName contextRef="C000203456_LG_ClassMember_8YR" id="ixv-16158">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity&#xae; Series Corporate Bond Fund&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000203456_ClassMember_AsOf_2018"
      decimals="0"
      id="ixv-225536"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000203456_ClassMember_AsOf_2019"
      decimals="0"
      id="ixv-225537"
      unitRef="usd">9963</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000203456_ClassMember_AsOf_2020"
      decimals="0"
      id="ixv-225538"
      unitRef="usd">11296</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000203456_ClassMember_AsOf_2021"
      decimals="0"
      id="ixv-225539"
      unitRef="usd">12221</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000203456_ClassMember_AsOf_2022"
      decimals="0"
      id="ixv-225540"
      unitRef="usd">12610</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000203456_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-225541"
      unitRef="usd">10698</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000203456_ClassMember_AsOf_2024"
      decimals="0"
      id="ixv-225542"
      unitRef="usd">10807</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000203456_ClassMember_AsOf_2025"
      decimals="0"
      id="ixv-225543"
      unitRef="usd">11903</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000203456_LG_1_AdditionalIndexMember_8YR"
      id="ixv-16195">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg U.S. Credit Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000203456_1_AdditionalIndexMember_AsOf_2018"
      decimals="0"
      id="ixv-225544"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000203456_1_AdditionalIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-225545"
      unitRef="usd">10005</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000203456_1_AdditionalIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-225546"
      unitRef="usd">11305</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000203456_1_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-225547"
      unitRef="usd">12107</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000203456_1_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-225548"
      unitRef="usd">12381</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000203456_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-225549"
      unitRef="usd">10594</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000203456_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-225550"
      unitRef="usd">10684</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000203456_1_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-225551"
      unitRef="usd">11644</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000203456_LG_2_AdditionalIndexMember_8YR"
      id="ixv-16232">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg U.S. Aggregate Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000203456_2_AdditionalIndexMember_AsOf_2018"
      decimals="0"
      id="ixv-225552"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000203456_2_AdditionalIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-225553"
      unitRef="usd">10014</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000203456_2_AdditionalIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-225554"
      unitRef="usd">11033</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000203456_2_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-225555"
      unitRef="usd">11747</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000203456_2_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-225556"
      unitRef="usd">11737</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000203456_2_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-225557"
      unitRef="usd">10386</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000203456_2_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-225558"
      unitRef="usd">10262</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000203456_2_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-225559"
      unitRef="usd">11010</oef:AccmVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000203456_ClassMember" id="ixv-16312">AVERAGE ANNUAL TOTAL RETURNS:

&#160;

1 Year

5 Year

Life of Fund&#160;A


Fidelity&#xae; Series Corporate Bond Fund

4.35%

0.32%

3.13%


Bloomberg U.S. Credit Bond Index

3.92%


-0.01%


2.74%


Bloomberg U.S. Aggregate Bond Index

3.14%


-0.68%


1.82%




A&#160; &#160;From August 17, 2018

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

&#160;


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





</oef:AvgAnnlRtrTableTextBlock>
    <oef:AvgAnnlRtrPct
      contextRef="C000203456_NoLoadClassMember_1YR"
      decimals="INF"
      id="ixv-225560"
      unitRef="pure">0.0435</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000203456_NoLoadClassMember_5YR"
      decimals="INF"
      id="ixv-225561"
      unitRef="pure">0.0032</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000203456_NoLoadClassMember_2024-09-01_2025-08-31"
      decimals="INF"
      id="ixv-225562"
      unitRef="pure">0.0313</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000203456_0_AdditionalIndexMember_1YR"
      decimals="INF"
      id="ixv-225563"
      unitRef="pure">0.0392</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000203456_0_AdditionalIndexMember_5YR"
      decimals="INF"
      id="ixv-225564"
      unitRef="pure">-0.0001</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000203456_0_AdditionalIndexMember_LOC"
      decimals="INF"
      id="ixv-225565"
      unitRef="pure">0.0274</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000203456_1_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-225566"
      unitRef="pure">0.0314</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000203456_1_BBIndexMember_5YR"
      decimals="INF"
      id="ixv-225567"
      unitRef="pure">-0.0068</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000203456_1_BBIndexMember_LOC"
      decimals="INF"
      id="ixv-225568"
      unitRef="pure">0.0182</oef:AvgAnnlRtrPct>
    <oef:PerfInceptionDate
      contextRef="C000203456_Perf_2018-08-17_ClassMember"
      id="ixv-16383">2018-08-17</oef:PerfInceptionDate>
    <oef:UpdPerfInfoLocationTextBlock contextRef="C000203456_ClassMember" id="ixv-16393">&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="C000203456_ClassMember" id="ixv-16405">&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="C000203456_ClassMember" id="ixv-16409">&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="C000203456_ClassMember" id="ixv-16415">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;Key Fund Statistics&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(as of August 31, 2025)&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;$&lt;/span&gt;838,718,706&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;599&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&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;39&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="C000203456_InstantMember"
      decimals="0"
      id="ixv-225569"
      unitRef="usd">838718706</us-gaap:AssetsNet>
    <oef:HoldingsCount
      contextRef="C000203456_InstantMember"
      decimals="INF"
      id="ixv-225570"
      unitRef="holding">599</oef:HoldingsCount>
    <oef:AdvisoryFeesPaidAmt
      contextRef="C000203456_ClassMember"
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&#160;
U.S. Government and U.S. Government Agency Obligations

10.1


AAA

0.0


AA

0.2


A

25.2


BBB

52.7


BB

5.0


B

0.9


Not Rated

0.0


Short-Term Investments and Net Other Assets (Liabilities)

5.9




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

U.S. Government and U.S. Government Agency Obligations - 10.1


&#160;

AAA - 0.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

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


&#160;

A - 25.2&#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;

BBB - 52.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BB - 5.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

B - 0.9&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Not Rated - 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;

Short-Term Investments and Net Other Assets (Liabilities) - 5.9


&#160;


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




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

83.2


U.S. Treasury Obligations

10.1


Asset-Backed Securities

0.5


Preferred Securities

0.2


Foreign Government and Government Agency Obligations

0.1


CMOs and Other Mortgage Related Securities

0.0


Short-Term Investments and Net Other Assets (Liabilities)

5.9




ASSET ALLOCATION (% of Fund's net assets)


&#160;



&#160;

Corporate Bonds - 83.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

U.S. Treasury Obligations - 10.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Asset-Backed Securities - 0.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

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


&#160;

Foreign Government and Government Agency Obligations - 0.1


&#160;

CMOs and Other Mortgage Related Securities - 0.0


&#160;

Short-Term Investments and Net Other Assets (Liabilities) - 5.9


&#160;






United States

82.8


United Kingdom

3.7


Canada

3.1


Ireland

2.3


Germany

1.5


Belgium

1.1


Japan

1.0


France

0.9


Netherlands

0.8


Others

2.8




GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

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


&#160;

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


&#160;

Canada - 3.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Ireland - 2.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Germany - 1.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Belgium - 1.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

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


&#160;

France - 0.9&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Netherlands - 0.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

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




&#160;




&#160;
&#160;
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    <oef:LargestHoldingsTableTextBlock contextRef="C000203456_ClassMember" id="ixv-16925">TOP HOLDINGS(% of Fund's net assets)

&#160;

&#160;


US Treasury Bonds

10.1


&#160;


Bank of America Corp

2.4


&#160;


Morgan Stanley

2.3


&#160;


JPMorgan Chase &amp; Co

2.3


&#160;


Wells Fargo &amp; Co

2.1


&#160;


Boeing Co

1.6


&#160;


Broadcom Inc

1.6


&#160;


CVS Health Corp

1.2


&#160;


Barclays PLC

1.2


&#160;


Charter Communications Operating LLC / Charter Communications Operating Capital

1.2


&#160;


&#160;

26.0

&#160;



</oef:LargestHoldingsTableTextBlock>
    <oef:PctOfNav
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      id="ixv-225599"
      unitRef="pure">0.101</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-225600"
      unitRef="pure">0.024</oef:PctOfNav>
    <oef:PctOfNav
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      unitRef="pure">0.021</oef:PctOfNav>
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      decimals="INF"
      id="ixv-225604"
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    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-17096">2025-08-31</dei:DocumentPeriodEndDate>
    <oef:MaterialFundChngNoticeTextBlock contextRef="C000235215_ClassMember" id="ixv-17100">This report describes changes to the Fund that occurred during the reporting period.</oef:MaterialFundChngNoticeTextBlock>
    <oef:FundName contextRef="C000235215_ClassMember" id="ixv-17111">Fidelity&#xae; SAI Sustainable Low Duration Bond Fund</oef:FundName>
    <oef:ClassName contextRef="C000235215_ClassMember" id="ixv-17114">Fidelity&#xae; SAI Sustainable Low Duration Bond Fund</oef:ClassName>
    <dei:TradingSymbol contextRef="C000235215_ClassMember" id="ixv-17118">FAPFX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000235215_ClassMember" id="ixv-17137">This annual shareholder report contains information about Fidelity&#xae; SAI Sustainable Low Duration Bond Fund for the period September 1, 2024 to August 31, 2025.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000235215_ClassMember" id="ixv-17139">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000235215_ClassMember" id="ixv-17144">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="C000235215_ClassMember" id="ixv-17146">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000235215_ClassMember" id="ixv-17149">1-800-544-3455</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000235215_ClassMember" id="ixv-17152">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000235215_ClassMember" id="ixv-17159">&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:45%; 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:24%; 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:30%; 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 $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:45%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity&#xae; SAI Sustainable Low Duration Bond Fund&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:24%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$ &lt;/span&gt;21&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:30%; 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="C000235215_ClassMember"
      decimals="0"
      id="ixv-225609"
      unitRef="usd">21</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000235215_ClassMember"
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      id="ixv-225610"
      unitRef="pure">0.0020</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000235215_ClassMember" id="ixv-17201">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What affected the Fund's performance this period?&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;U.S. taxable investment-grade bonds posted a solid advance for the 12 months ending August 31, 2025, navigating tariff-related uncertainty since late 2024 but buoyed by relatively stable consumer inflation, a resilient economy and the expectation of policy interest-rate cuts by the U.S. Federal Reserve in the second half of 2025.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Against this backdrop, the fund's strategy of holding short-term debt in high-quality corporations contributed to performance versus the all-U.S.-Treasury benchmark for the fiscal year. Within corporates, debt holdings among financial institutions, especially banks, and industrial firms, particularly in the consumer cyclical, consumer non-cyclical and communications segments, added notable value.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Non-benchmark exposure to asset-backed securities, primarily car loan debt, also meaningfully contributed.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;In contrast, the fund's yield-curve positioning detracted from relative performance.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;A small allocation to interest-earning cash was a modest drag as well.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;At period end, corporates made up about 45% of fund assets, down from roughly 60% a year ago. Exposure to U.S. Treasurys increased slightly from 30% to roughly 31% of assets, while exposure to ABS rose from roughly 8% of assets to about 18% as of August 31.&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;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:FactorsAffectingPerfTextBlock>
    <oef:LineGraphTableTextBlock contextRef="C000235215_ClassMember" id="ixv-17230">How did the Fund perform over the life of Fund?

 &#160;&#160;
CUMULATIVE PERFORMANCE
April 13, 2022 through August 31, 2025.
Initial investment of $10,000.
Fidelity&#xae; SAI Sustainable Low Duration Bond Fund


$10,000

$10,009


$10,431


$11,045



Bloomberg US Treasury Bill: 6-9 Months Index


$10,000

$9,990


$10,301


$10,854



Bloomberg U.S. Aggregate Bond Index


$10,000

$9,696


$9,581


$10,280



&#160;

2022

2023

2024

2025









&#160;
</oef:LineGraphTableTextBlock>
    <oef:LineGraphAndTableMeasureName contextRef="C000235215_LG_ClassMember_4YR" id="ixv-17249">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity&#xae; SAI Sustainable Low Duration Bond Fund&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000235215_ClassMember_AsOf_2022"
      decimals="0"
      id="ixv-225611"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235215_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-225612"
      unitRef="usd">10009</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235215_ClassMember_AsOf_2024"
      decimals="0"
      id="ixv-225613"
      unitRef="usd">10431</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235215_ClassMember_AsOf_2025"
      decimals="0"
      id="ixv-225614"
      unitRef="usd">11045</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000235215_LG_1_AdditionalIndexMember_4YR"
      id="ixv-17270">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg US Treasury Bill: 6-9 Months Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000235215_1_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-225615"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235215_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-225616"
      unitRef="usd">9990</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235215_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-225617"
      unitRef="usd">10301</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235215_1_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-225618"
      unitRef="usd">10854</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000235215_LG_2_AdditionalIndexMember_4YR"
      id="ixv-17291">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg U.S. Aggregate Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000235215_2_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-225619"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235215_2_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-225620"
      unitRef="usd">9696</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235215_2_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-225621"
      unitRef="usd">9581</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000235215_2_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-225622"
      unitRef="usd">10280</oef:AccmVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000235215_ClassMember" id="ixv-17343">AVERAGE ANNUAL TOTAL RETURNS:

&#160;

1 Year

Life of Fund&#160;A


Fidelity&#xae; SAI Sustainable Low Duration Bond Fund

4.78%

4.41%


Bloomberg US Treasury Bill: 6-9 Months Index

4.29%


3.73%


Bloomberg U.S. Aggregate Bond Index

3.14%


1.74%




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="C000235215_NoLoadClassMember_1YR"
      decimals="INF"
      id="ixv-225623"
      unitRef="pure">0.0478</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235215_NoLoadClassMember_2024-09-01_2025-08-31"
      decimals="INF"
      id="ixv-225624"
      unitRef="pure">0.0441</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235215_0_AdditionalIndexMember_1YR"
      decimals="INF"
      id="ixv-225625"
      unitRef="pure">0.0429</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235215_0_AdditionalIndexMember_LOC"
      decimals="INF"
      id="ixv-225626"
      unitRef="pure">0.0373</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235215_1_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-225627"
      unitRef="pure">0.0314</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000235215_1_BBIndexMember_LOC"
      decimals="INF"
      id="ixv-225628"
      unitRef="pure">0.0174</oef:AvgAnnlRtrPct>
    <oef:PerfInceptionDate
      contextRef="C000235215_Perf_2022-04-13_ClassMember"
      id="ixv-17398">2022-04-13</oef:PerfInceptionDate>
    <oef:UpdPerfInfoLocationTextBlock contextRef="C000235215_ClassMember" id="ixv-17408">&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="C000235215_ClassMember" id="ixv-17420">&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="C000235215_ClassMember" id="ixv-17424">&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="C000235215_ClassMember" id="ixv-17430">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;Key Fund Statistics&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(as of August 31, 2025)&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;$&lt;/span&gt;51,874,092&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;320&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;81,168&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;57&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="C000235215_InstantMember"
      decimals="0"
      id="ixv-225629"
      unitRef="usd">51874092</us-gaap:AssetsNet>
    <oef:HoldingsCount
      contextRef="C000235215_InstantMember"
      decimals="INF"
      id="ixv-225630"
      unitRef="holding">320</oef:HoldingsCount>
    <oef:AdvisoryFeesPaidAmt
      contextRef="C000235215_ClassMember"
      decimals="0"
      id="ixv-225631"
      unitRef="usd">81168</oef:AdvisoryFeesPaidAmt>
    <us-gaap:InvestmentCompanyPortfolioTurnover
      contextRef="C000235215_ClassMember"
      decimals="INF"
      id="ixv-225632"
      unitRef="pure">0.57</us-gaap:InvestmentCompanyPortfolioTurnover>
    <oef:HoldingsTableTextBlock contextRef="C000235215_ClassMember" id="ixv-17505">
&#160;
U.S. Government and U.S. Government Agency Obligations

31.1


AAA

17.2


AA

3.1


A

23.9


BBB

17.8


BB

0.2


Not Rated

1.6


Short-Term Investments and Net Other Assets (Liabilities)

5.1




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

U.S. Government and U.S. Government Agency Obligations - 31.1


&#160;

AAA - 17.2&#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;

AA - 3.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

A - 23.9&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BBB - 17.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

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


&#160;

Not Rated - 1.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Short-Term Investments and Net Other Assets (Liabilities) - 5.1


&#160;


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




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

44.9


U.S. Treasury Obligations

31.1


Asset-Backed Securities

18.3


CMOs and Other Mortgage Related Securities

0.5


Other Investments

0.1


Short-Term Investments and Net Other Assets (Liabilities)

5.1




ASSET ALLOCATION (% of Fund's net assets)


&#160;



&#160;

Corporate Bonds - 44.9&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

U.S. Treasury Obligations - 31.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Asset-Backed Securities - 18.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

CMOs and Other Mortgage Related Securities - 0.5


&#160;

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


&#160;

Short-Term Investments and Net Other Assets (Liabilities) - 5.1


&#160;






United States

87.6


Canada

3.6


United Kingdom

2.7


Ireland

1.5


Netherlands

1.4


Japan

0.8


Sweden

0.4


Italy

0.4


Norway

0.4


Others

1.2




GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

United States - 87.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Canada - 3.6&#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;

United Kingdom - 2.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Ireland - 1.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Netherlands - 1.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Japan - 0.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Sweden - 0.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Italy - 0.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Norway - 0.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Others - 1.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;




&#160;




&#160;
&#160;
</oef:HoldingsTableTextBlock>
    <oef:PctOfNav
      contextRef="C000235215_QD_USGovernmentandUSGovernmentAgencyObligations_Member"
      decimals="INF"
      id="ixv-225633"
      unitRef="pure">0.311</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235215_QD_AAA_Member"
      decimals="INF"
      id="ixv-225634"
      unitRef="pure">0.172</oef:PctOfNav>
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      decimals="INF"
      id="ixv-225635"
      unitRef="pure">0.031</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-225636"
      unitRef="pure">0.239</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235215_QD_BBB_Member"
      decimals="INF"
      id="ixv-225637"
      unitRef="pure">0.178</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235215_QD_BB_Member"
      decimals="INF"
      id="ixv-225638"
      unitRef="pure">0.002</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235215_QD_NotRated_Member"
      decimals="INF"
      id="ixv-225639"
      unitRef="pure">0.016</oef:PctOfNav>
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      decimals="INF"
      id="ixv-225640"
      unitRef="pure">0.051</oef:PctOfNav>
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      decimals="INF"
      id="ixv-225641"
      unitRef="pure">0.449</oef:PctOfNav>
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      contextRef="C000235215_AA_USTreasuryObligations_Member"
      decimals="INF"
      id="ixv-225642"
      unitRef="pure">0.311</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235215_AA_AssetBackedSecurities_Member"
      decimals="INF"
      id="ixv-225643"
      unitRef="pure">0.183</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-225644"
      unitRef="pure">0.005</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235215_AA_OtherInvestments_Member"
      decimals="INF"
      id="ixv-225645"
      unitRef="pure">0.001</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-225646"
      unitRef="pure">0.051</oef:PctOfNav>
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      decimals="INF"
      id="ixv-225647"
      unitRef="pure">0.876</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-225648"
      unitRef="pure">0.036</oef:PctOfNav>
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      decimals="INF"
      id="ixv-225649"
      unitRef="pure">0.027</oef:PctOfNav>
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      decimals="INF"
      id="ixv-225650"
      unitRef="pure">0.015</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235215_GD_NL_Member"
      decimals="INF"
      id="ixv-225651"
      unitRef="pure">0.014</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-225653"
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      unitRef="pure">0.004</oef:PctOfNav>
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    <oef:LargestHoldingsTableTextBlock contextRef="C000235215_ClassMember" id="ixv-17914">TOP HOLDINGS(% of Fund's net assets)

&#160;

&#160;


US Treasury Bill

22.5


&#160;


US Treasury Notes

8.6


&#160;


Bank of America Corp

1.6


&#160;


JPMorgan Chase &amp; Co

1.6


&#160;


Goldman Sachs Group Inc/The

1.6


&#160;


Morgan Stanley

1.5


&#160;


Wells Fargo &amp; Co

1.2


&#160;


Citigroup Inc

1.1


&#160;


GMF Floorplan Owner Revolving Trust

1.1


&#160;


Athene Global Funding

0.9


&#160;


&#160;

41.7

&#160;



</oef:LargestHoldingsTableTextBlock>
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      id="ixv-225657"
      unitRef="pure">0.225</oef:PctOfNav>
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      decimals="INF"
      id="ixv-225658"
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      id="ixv-225660"
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      unitRef="pure">0.016</oef:PctOfNav>
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      decimals="INF"
      id="ixv-225662"
      unitRef="pure">0.015</oef:PctOfNav>
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      decimals="INF"
      id="ixv-225663"
      unitRef="pure">0.012</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-225664"
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    <oef:PctOfNav
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      id="ixv-225665"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
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      id="ixv-225666"
      unitRef="pure">0.009</oef:PctOfNav>
    <oef:MaterialFundChngTextBlock contextRef="C000235215_ClassMember" id="ixv-18039">
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;How has the Fund changed?&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;This is a summary of certain changes to the Fund since September 1, 2024. 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;October 30, 2025 at &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;fundresearch.fidelity.com/prospectus/sec&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt; or upon request at &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;1-800-544-3455&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:0px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt; or by sending an e-mail to &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;fidfunddocuments@fidelity.com&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;table cellpadding="0" cellspacing="0" style="border-collapse:collapse;border-style:none;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:50%; background-color:#ebf3e9;border-right:2px dashed #368627;padding:19px 19px 19px 19px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;The fees associated with this class changed during the reporting year. The variations in class fees are primarily the result of the following changes:&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;ul style="color:#000000;list-style-type:disc;margin:0px 0px 0px 25px;padding:0px;"&gt;&lt;li style="margin:5px 0px 2px 24px;padding:0px 0px 0px 0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Operating expenses&lt;/span&gt;&lt;/li&gt;&lt;li style="margin:5px 0px 2px 24px;padding:0px 0px 0px 0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Expense reductions&lt;/span&gt;&lt;/li&gt;&lt;/ul&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;&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;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;The fund's name changed from Fidelity&#xae; SAI Sustainable Low Duration Income Fund to Fidelity&#xae; SAI Sustainable Low Duration Bond Fund during the reporting period.&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;br/&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;/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="C000235215_ClassMember" id="ixv-18045">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;This is a summary of certain changes to the Fund since September 1, 2024. 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;October 30, 2025 at &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;fundresearch.fidelity.com/prospectus/sec&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt; or upon request at &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;1-800-544-3455&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:0px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt; or by sending an e-mail to &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;fidfunddocuments@fidelity.com&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;.&lt;/span&gt;</oef:SummaryOfChngLegendTextBlock>
    <oef:UpdProspectusWebAddress contextRef="C000235215_ClassMember" id="ixv-18049">&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="C000235215_ClassMember" id="ixv-18052">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;1-800-544-3455&lt;/span&gt;</oef:UpdProspectusPhoneNumber>
    <oef:UpdProspectusEmailAddress contextRef="C000235215_ClassMember" id="ixv-18056">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;fidfunddocuments@fidelity.com&lt;/span&gt;</oef:UpdProspectusEmailAddress>
    <oef:MaterialFundChngExpensesTextBlock contextRef="C000235215_ClassMember" id="ixv-18067">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;The fees associated with this class changed during the reporting year. The variations in class fees are primarily the result of the following changes:&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;ul style="color:#000000;list-style-type:disc;margin:0px 0px 0px 25px;padding:0px;"&gt;&lt;li style="margin:5px 0px 2px 24px;padding:0px 0px 0px 0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Operating expenses&lt;/span&gt;&lt;/li&gt;&lt;li style="margin:5px 0px 2px 24px;padding:0px 0px 0px 0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Expense reductions&lt;/span&gt;&lt;/li&gt;&lt;/ul&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:MaterialFundChngExpensesTextBlock>
    <oef:MaterialFundChngNameTextBlock contextRef="C000235215_ClassMember" id="ixv-18081">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;The fund's name changed from Fidelity&#xae; SAI Sustainable Low Duration Income Fund to Fidelity&#xae; SAI Sustainable Low Duration Bond Fund during the reporting period.&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;br/&gt;&lt;/div&gt;</oef:MaterialFundChngNameTextBlock>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-18137">2025-08-31</dei:DocumentPeriodEndDate>
    <oef:FundName contextRef="C000242809_ClassMember" id="ixv-18149">Fidelity&#xae; SAI Investment Grade Securitized Fund</oef:FundName>
    <oef:ClassName contextRef="C000242809_ClassMember" id="ixv-18152">Fidelity&#xae; SAI Investment Grade Securitized Fund</oef:ClassName>
    <dei:TradingSymbol contextRef="C000242809_ClassMember" id="ixv-18156">FSMOX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000242809_ClassMember" id="ixv-18175">This annual shareholder report contains information about Fidelity&#xae; SAI Investment Grade Securitized Fund for the period September 1, 2024 to August 31, 2025.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000242809_ClassMember" id="ixv-18177">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000242809_ClassMember" id="ixv-18182">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="C000242809_ClassMember" id="ixv-18184">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000242809_ClassMember" id="ixv-18187">1-800-544-3455</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000242809_ClassMember" id="ixv-18190">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000242809_ClassMember" id="ixv-18197">&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:45%; 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:24%; 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:30%; 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 $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:45%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity&#xae; SAI Investment Grade Securitized Fund&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:24%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$ &lt;/span&gt;31&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:30%; 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>
    <oef:ExpensesPaidAmt
      contextRef="C000242809_ClassMember"
      decimals="0"
      id="ixv-225667"
      unitRef="usd">31</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000242809_ClassMember"
      decimals="INF"
      id="ixv-225668"
      unitRef="pure">0.0031</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000242809_ClassMember" id="ixv-18239">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What affected the Fund's performance this period?&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;U.S. taxable investment-grade bonds posted a solid advance for the 12 months ending August 31, 2025, navigating tariff-related uncertainty since late 2024 but buoyed by relatively stable consumer inflation, a resilient economy and the expectation of policy interest-rate cuts by the U.S. Federal Reserve in the second half of 2025.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Against this backdrop, an underweight to MBS made up of 15-year mortgages detracted from the fund's performance versus the benchmark Bloomberg U.S. Securitized Index for the fiscal year.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;An underweight in Ginnie Mae securities with a coupon of 3% to 4.5% also hurt.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;In contrast, an overweight in non-agency commercial mortgage-backed securities contributed to performance versus the benchmark.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;An overweight in agency collateralized mortgage obligation floaters also helped for the 12 months.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Lastly, overweights in higher-coupon Fannie Mae and Freddie Mac MBS contributed to relative performance, as did an overweight in Ginnie Mae MBS with a coupon of 6%.&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="C000242809_ClassMember" id="ixv-18263">How did the Fund perform over the life of Fund?

 &#160;&#160;
CUMULATIVE PERFORMANCE
May 17, 2023 through August 31, 2025.
Initial investment of $10,000.
Fidelity&#xae; SAI Investment Grade Securitized Fund


$10,000

$9,858


$10,632



Bloomberg U.S. Securitized Index


$10,000

$9,861


$10,606



Bloomberg U.S. Aggregate Bond Index


$10,000

$9,877


$10,598



&#160;

2023

2024

2025









&#160;
</oef:LineGraphTableTextBlock>
    <oef:LineGraphAndTableMeasureName contextRef="C000242809_LG_ClassMember_3YR" id="ixv-18282">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity&#xae; SAI Investment Grade Securitized Fund&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000242809_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-225669"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000242809_ClassMember_AsOf_2024"
      decimals="0"
      id="ixv-225670"
      unitRef="usd">9858</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000242809_ClassMember_AsOf_2025"
      decimals="0"
      id="ixv-225671"
      unitRef="usd">10632</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000242809_LG_1_AdditionalIndexMember_3YR"
      id="ixv-18299">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg U.S. Securitized Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000242809_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-225672"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000242809_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-225673"
      unitRef="usd">9861</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000242809_1_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-225674"
      unitRef="usd">10606</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000242809_LG_2_AdditionalIndexMember_3YR"
      id="ixv-18316">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg U.S. Aggregate Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000242809_2_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-225675"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000242809_2_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-225676"
      unitRef="usd">9877</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000242809_2_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-225677"
      unitRef="usd">10598</oef:AccmVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000242809_ClassMember" id="ixv-18361">AVERAGE ANNUAL TOTAL RETURNS:

&#160;

1 Year

Life of Fund&#160;A


Fidelity&#xae; SAI Investment Grade Securitized Fund

3.55%

4.28%


Bloomberg U.S. Securitized Index

3.52%


4.16%


Bloomberg U.S. Aggregate Bond Index

3.14%


3.96%




A&#160; &#160;From May 17, 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
      contextRef="C000242809_NoLoadClassMember_1YR"
      decimals="INF"
      id="ixv-225678"
      unitRef="pure">0.0355</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000242809_NoLoadClassMember_2024-09-01_2025-08-31"
      decimals="INF"
      id="ixv-225679"
      unitRef="pure">0.0428</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000242809_0_AdditionalIndexMember_1YR"
      decimals="INF"
      id="ixv-225680"
      unitRef="pure">0.0352</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000242809_0_AdditionalIndexMember_LOC"
      decimals="INF"
      id="ixv-225681"
      unitRef="pure">0.0416</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000242809_1_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-225682"
      unitRef="pure">0.0314</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000242809_1_BBIndexMember_LOC"
      decimals="INF"
      id="ixv-225683"
      unitRef="pure">0.0396</oef:AvgAnnlRtrPct>
    <oef:PerfInceptionDate
      contextRef="C000242809_Perf_2023-05-17_ClassMember"
      id="ixv-18416">2023-05-17</oef:PerfInceptionDate>
    <oef:UpdPerfInfoLocationTextBlock contextRef="C000242809_ClassMember" id="ixv-18426">&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="C000242809_ClassMember" id="ixv-18438">&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="C000242809_ClassMember" id="ixv-18442">&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="C000242809_ClassMember" id="ixv-18448">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;Key Fund Statistics&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(as of August 31, 2025)&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;$&lt;/span&gt;1,291,988,839&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;1,606&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;3,691,783&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;715&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="C000242809_InstantMember"
      decimals="0"
      id="ixv-225684"
      unitRef="usd">1291988839</us-gaap:AssetsNet>
    <oef:HoldingsCount
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      decimals="INF"
      id="ixv-225685"
      unitRef="holding">1606</oef:HoldingsCount>
    <oef:AdvisoryFeesPaidAmt
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      decimals="0"
      id="ixv-225686"
      unitRef="usd">3691783</oef:AdvisoryFeesPaidAmt>
    <us-gaap:InvestmentCompanyPortfolioTurnover
      contextRef="C000242809_ClassMember"
      decimals="INF"
      id="ixv-225687"
      unitRef="pure">7.15</us-gaap:InvestmentCompanyPortfolioTurnover>
    <oef:HoldingsTableTextBlock contextRef="C000242809_ClassMember" id="ixv-18523">
&#160;
U.S. Government and U.S. Government Agency Obligations

94.3


AAA

9.3


AA

0.8


A

0.0


BBB

0.0


Not Rated

17.9




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

U.S. Government and U.S. Government Agency Obligations - 94.3


&#160;

AAA - 9.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

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


&#160;

A - 0.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BBB - 0.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Not Rated - 17.9&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


Short-Term Investments and Net Other Assets (Liabilities) - (22.3)%


&#160;


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




&#160;
&#160;
&#160;
&#160;
U.S. Government Agency - Mortgage Securities

90.9


CMOs and Other Mortgage Related Securities

24.8


U.S. Treasury Obligations

3.4


Asset-Backed Securities

2.9


Options

0.3




ASSET ALLOCATION (% of Fund's net assets)


&#160;



&#160;

U.S. Government Agency - Mortgage Securities - 90.9


&#160;

CMOs and Other Mortgage Related Securities - 24.8


&#160;

U.S. Treasury Obligations - 3.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Asset-Backed Securities - 2.9&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Options - 0.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


Short-Term Investments and Net Other Assets (Liabilities) - (22.3)%


&#160;






United States

99.9


Canada

0.1




GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

United States - 99.9&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Canada - 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;




&#160;
&#160;
</oef:HoldingsTableTextBlock>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-225688"
      unitRef="pure">0.943</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000242809_QD_AAA_Member"
      decimals="INF"
      id="ixv-225689"
      unitRef="pure">0.093</oef:PctOfNav>
    <oef:PctOfNav
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      id="ixv-225690"
      unitRef="pure">0.008</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-225691"
      unitRef="pure">0.000</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000242809_QD_BBB_Member"
      decimals="INF"
      id="ixv-225692"
      unitRef="pure">0.000</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-225693"
      unitRef="pure">0.179</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000242809_AA_USGovernmentAgencyMortgageSecurities_Member"
      decimals="INF"
      id="ixv-225694"
      unitRef="pure">0.909</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000242809_AA_CMOsandOtherMortgageRelatedSecurities_Member"
      decimals="INF"
      id="ixv-225695"
      unitRef="pure">0.248</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000242809_AA_USTreasuryObligations_Member"
      decimals="INF"
      id="ixv-225696"
      unitRef="pure">0.034</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000242809_AA_AssetBackedSecurities_Member"
      decimals="INF"
      id="ixv-225697"
      unitRef="pure">0.029</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000242809_AA_Options_Member"
      decimals="INF"
      id="ixv-225698"
      unitRef="pure">0.003</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000242809_GD_US_Member"
      decimals="INF"
      id="ixv-225699"
      unitRef="pure">0.999</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000242809_GD_CA_Member"
      decimals="INF"
      id="ixv-225700"
      unitRef="pure">0.001</oef:PctOfNav>
    <oef:LargestHoldingsTableTextBlock contextRef="C000242809_ClassMember" id="ixv-18797">TOP HOLDINGS(% of Fund's net assets)

&#160;

&#160;


Fannie Mae Mortgage pass-thru certificates

33.9


&#160;


Ginnie Mae II Pool

22.0


&#160;


Freddie Mac Gold Pool

19.0


&#160;


Uniform Mortgage Backed Securities

10.7


&#160;


Freddie Mac Multifamily Structured pass-thru certificates

5.9


&#160;


Fannie Mae Guaranteed REMIC

5.8


&#160;


Ginnie Mae I Pool

4.3


&#160;


US Treasury Notes

1.8


&#160;


Freddie Mac Non Gold Pool

1.6


&#160;


US Treasury Bonds

1.6


&#160;


&#160;

106.6

&#160;



</oef:LargestHoldingsTableTextBlock>
    <oef:PctOfNav
      contextRef="C000242809_TH_0_Member"
      decimals="INF"
      id="ixv-225701"
      unitRef="pure">0.339</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000242809_TH_1_Member"
      decimals="INF"
      id="ixv-225702"
      unitRef="pure">0.220</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000242809_TH_2_Member"
      decimals="INF"
      id="ixv-225703"
      unitRef="pure">0.190</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000242809_TH_3_Member"
      decimals="INF"
      id="ixv-225704"
      unitRef="pure">0.107</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000242809_TH_4_Member"
      decimals="INF"
      id="ixv-225705"
      unitRef="pure">0.059</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000242809_TH_5_Member"
      decimals="INF"
      id="ixv-225706"
      unitRef="pure">0.058</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000242809_TH_6_Member"
      decimals="INF"
      id="ixv-225707"
      unitRef="pure">0.043</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000242809_TH_7_Member"
      decimals="INF"
      id="ixv-225708"
      unitRef="pure">0.018</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000242809_TH_8_Member"
      decimals="INF"
      id="ixv-225709"
      unitRef="pure">0.016</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000242809_TH_9_Member"
      decimals="INF"
      id="ixv-225710"
      unitRef="pure">0.016</oef:PctOfNav>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-18968">2025-08-31</dei:DocumentPeriodEndDate>
    <oef:FundName contextRef="C000098000_ClassMember" id="ixv-18980">Fidelity&#xae; Conservative Income Bond Fund</oef:FundName>
    <oef:ClassName contextRef="C000098000_ClassMember" id="ixv-18983">Fidelity&#xae; Conservative Income Bond Fund</oef:ClassName>
    <dei:TradingSymbol contextRef="C000098000_ClassMember" id="ixv-18987">FCNVX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000098000_ClassMember" id="ixv-19006">This annual shareholder report contains information about Fidelity&#xae; Conservative Income Bond Fund for the period September 1, 2024 to August 31, 2025.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000098000_ClassMember" id="ixv-19008">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000098000_ClassMember" id="ixv-19013">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="C000098000_ClassMember" id="ixv-19015">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000098000_ClassMember" id="ixv-19018">1-800-544-8544</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000098000_ClassMember" id="ixv-19021">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000098000_ClassMember" id="ixv-19028">&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:45%; 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:24%; 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:30%; 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 $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:45%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity&#xae; Conservative Income Bond Fund&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:24%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$ &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:30%; 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="C000098000_ClassMember"
      decimals="0"
      id="ixv-225711"
      unitRef="usd">26</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000098000_ClassMember"
      decimals="INF"
      id="ixv-225712"
      unitRef="pure">0.0025</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000098000_ClassMember" id="ixv-19070">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What affected the Fund's performance this period?&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;U.S. taxable investment-grade bonds posted a solid advance for the 12 months ending August 31, 2025, navigating tariff-related uncertainty since late 2024 but buoyed by relatively stable consumer inflation, a resilient economy and the expectation of policy interest-rate cuts by the U.S. Federal Reserve in the second half of 2025.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Against this backdrop, the fund's strategy of holding short-term debt in high-quality corporations contributed to performance versus the all-U.S.-Treasury benchmark for the fiscal year. Within corporates, debt holdings among financial institutions - especially banks - and industrial firms, particularly in the consumer cyclical and consumer non-cyclical segments, added notable value.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Non-benchmark exposure to asset-backed securities, primarily car loan debt, also meaningfully contributed.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity 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, a roughly 13% average allocation to cash - which the fund maintained for liquidity and solid interest return - detracted from relative performance.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;At period end, corporates made up about 53% of fund assets, down from roughly 54% a year ago. At the same time, exposure to U.S. Treasurys slightly increased, from 17% to 18% of assets, and the portfolio's out-of-benchmark position in ABS rose from approximately 14% of assets to 16% as of August 31.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:FactorsAffectingPerfTextBlock>
    <oef:LineGraphTableTextBlock contextRef="C000098000_ClassMember" id="ixv-19091">How did the Fund perform over the past 10 years?

 &#160;&#160;
CUMULATIVE PERFORMANCE
August 31, 2015 through August 31, 2025.
Initial investment of $10,000.
Fidelity&#xae; Conservative Income Bond Fund


$10,000

$10,093


$10,222


$10,413


$10,683


$10,883


$10,905


$10,908


$11,437


$12,101


$12,685



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


$10,000

$10,038


$10,105


$10,256


$10,513


$10,671


$10,680


$10,710


$11,169


$11,789


$12,331



Bloomberg U.S. Aggregate Bond Index


$10,000

$10,597


$10,649


$10,537


$11,609


$12,360


$12,350


$10,928


$10,797


$11,585


$11,949



&#160;

2015

2016

2017

2018

2019

2020

2021

2022

2023

2024

2025









&#160;
</oef:LineGraphTableTextBlock>
    <oef:LineGraphAndTableMeasureName contextRef="C000098000_LG_ClassMember_11YR" id="ixv-19110">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity&#xae; Conservative Income Bond Fund&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000098000_ClassMember_AsOf_2015"
      decimals="0"
      id="ixv-225713"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000098000_ClassMember_AsOf_2016"
      decimals="0"
      id="ixv-225714"
      unitRef="usd">10093</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000098000_ClassMember_AsOf_2017"
      decimals="0"
      id="ixv-225715"
      unitRef="usd">10222</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000098000_ClassMember_AsOf_2018"
      decimals="0"
      id="ixv-225716"
      unitRef="usd">10413</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000098000_ClassMember_AsOf_2019"
      decimals="0"
      id="ixv-225717"
      unitRef="usd">10683</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000098000_ClassMember_AsOf_2020"
      decimals="0"
      id="ixv-225718"
      unitRef="usd">10883</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000098000_ClassMember_AsOf_2021"
      decimals="0"
      id="ixv-225719"
      unitRef="usd">10905</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000098000_ClassMember_AsOf_2022"
      decimals="0"
      id="ixv-225720"
      unitRef="usd">10908</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000098000_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-225721"
      unitRef="usd">11437</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000098000_ClassMember_AsOf_2024"
      decimals="0"
      id="ixv-225722"
      unitRef="usd">12101</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000098000_ClassMember_AsOf_2025"
      decimals="0"
      id="ixv-225723"
      unitRef="usd">12685</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000098000_LG_1_AdditionalIndexMember_11YR"
      id="ixv-19159">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg U.S. 3-6 Month Treasury Bill Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000098000_1_AdditionalIndexMember_AsOf_2015"
      decimals="0"
      id="ixv-225724"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000098000_1_AdditionalIndexMember_AsOf_2016"
      decimals="0"
      id="ixv-225725"
      unitRef="usd">10038</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000098000_1_AdditionalIndexMember_AsOf_2017"
      decimals="0"
      id="ixv-225726"
      unitRef="usd">10105</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000098000_1_AdditionalIndexMember_AsOf_2018"
      decimals="0"
      id="ixv-225727"
      unitRef="usd">10256</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000098000_1_AdditionalIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-225728"
      unitRef="usd">10513</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000098000_1_AdditionalIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-225729"
      unitRef="usd">10671</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000098000_1_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-225730"
      unitRef="usd">10680</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000098000_1_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-225731"
      unitRef="usd">10710</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000098000_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-225732"
      unitRef="usd">11169</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000098000_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-225733"
      unitRef="usd">11789</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000098000_1_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-225734"
      unitRef="usd">12331</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000098000_LG_2_AdditionalIndexMember_11YR"
      id="ixv-19208">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg U.S. Aggregate Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000098000_2_AdditionalIndexMember_AsOf_2015"
      decimals="0"
      id="ixv-225735"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000098000_2_AdditionalIndexMember_AsOf_2016"
      decimals="0"
      id="ixv-225736"
      unitRef="usd">10597</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000098000_2_AdditionalIndexMember_AsOf_2017"
      decimals="0"
      id="ixv-225737"
      unitRef="usd">10649</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000098000_2_AdditionalIndexMember_AsOf_2018"
      decimals="0"
      id="ixv-225738"
      unitRef="usd">10537</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000098000_2_AdditionalIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-225739"
      unitRef="usd">11609</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000098000_2_AdditionalIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-225740"
      unitRef="usd">12360</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000098000_2_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-225741"
      unitRef="usd">12350</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000098000_2_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-225742"
      unitRef="usd">10928</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000098000_2_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-225743"
      unitRef="usd">10797</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000098000_2_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-225744"
      unitRef="usd">11585</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000098000_2_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-225745"
      unitRef="usd">11949</oef:AccmVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000098000_ClassMember" id="ixv-19309">AVERAGE ANNUAL TOTAL RETURNS:

&#160;

1 Year

5 Year

10 Year


Fidelity&#xae; Conservative Income Bond Fund

4.82%

3.11%

2.41%


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

4.60%


2.93%


2.12%


Bloomberg U.S. Aggregate Bond Index

3.14%


-0.68%


1.80%




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

&#160;


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





</oef:AvgAnnlRtrTableTextBlock>
    <oef:AvgAnnlRtrPct
      contextRef="C000098000_NoLoadClassMember_1YR"
      decimals="INF"
      id="ixv-225746"
      unitRef="pure">0.0482</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000098000_NoLoadClassMember_5YR"
      decimals="INF"
      id="ixv-225747"
      unitRef="pure">0.0311</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000098000_NoLoadClassMember_10YR"
      decimals="INF"
      id="ixv-225748"
      unitRef="pure">0.0241</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000098000_0_AdditionalIndexMember_1YR"
      decimals="INF"
      id="ixv-225749"
      unitRef="pure">0.0460</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000098000_0_AdditionalIndexMember_5YR"
      decimals="INF"
      id="ixv-225750"
      unitRef="pure">0.0293</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000098000_0_AdditionalIndexMember_10YR"
      decimals="INF"
      id="ixv-225751"
      unitRef="pure">0.0212</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000098000_1_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-225752"
      unitRef="pure">0.0314</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
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      id="ixv-225753"
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    <oef:AvgAnnlRtrPct
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      decimals="INF"
      id="ixv-225754"
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    <oef:UpdPerfInfoLocationTextBlock contextRef="C000098000_ClassMember" id="ixv-19380">&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="C000098000_ClassMember" id="ixv-19392">&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="C000098000_ClassMember" id="ixv-19396">&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="C000098000_ClassMember" id="ixv-19402">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;Key Fund Statistics&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(as of August 31, 2025)&lt;/span&gt;&lt;/div&gt;
&lt;div&gt;&lt;span style="font-size:11px;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;table cellpadding="0" cellspacing="1" style="border-collapse:separate;border-style:none;margin:auto;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:63%; " valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:bold;"&gt;KEY FACTS&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt; &lt;span&gt;&#160;&lt;/span&gt;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fund Size&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;7,680,799,262&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;345&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;13,748,867&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;73&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>
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&#160;
U.S. Government and U.S. Government Agency Obligations

18.0


AAA

15.6


AA

4.4


A

23.8


BBB

9.7


Not Rated

0.8


Short-Term Investments and Net Other Assets (Liabilities)

27.7




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

U.S. Government and U.S. Government Agency Obligations - 18.0


&#160;

AAA - 15.6&#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;

AA - 4.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

A - 23.8&#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 - 9.7&#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;

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


&#160;

Short-Term Investments and Net Other Assets (Liabilities) - 27.7


&#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;
&#160;
Corporate Bonds

38.2


U.S. Treasury Obligations

18.0


Asset-Backed Securities

16.1


Other Investments

0.0


Short-Term Investments and Net Other Assets (Liabilities)

27.7




ASSET ALLOCATION (% of Fund's net assets)


&#160;



&#160;

Corporate Bonds - 38.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

U.S. Treasury Obligations - 18.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Asset-Backed Securities - 16.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Other Investments - 0.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Short-Term Investments and Net Other Assets (Liabilities) - 27.7


&#160;






United States

85.1


Canada

3.5


United Kingdom

2.7


Germany

2.4


Netherlands

1.5


Japan

0.7


Ireland

0.7


France

0.7


Australia

0.6


Others

2.1




GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

United States - 85.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Canada - 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;

United Kingdom - 2.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Germany - 2.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Netherlands - 1.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

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


&#160;

Ireland - 0.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

France - 0.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Australia - 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;

Others - 2.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;




&#160;




&#160;
&#160;
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    <oef:PctOfNav
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    <oef:PctOfNav
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      unitRef="pure">0.021</oef:PctOfNav>
    <oef:LargestHoldingsTableTextBlock contextRef="C000098000_ClassMember" id="ixv-19860">TOP HOLDINGS(% of Fund's net assets)

&#160;

&#160;


US Treasury Bill

14.2


&#160;


US Treasury Notes

3.8


&#160;


Mitsubishi UFJ Trust &amp; Banking Corp/NY

1.6


&#160;


Mizuho Bank Ltd/New York NY

1.4


&#160;


Bank of Nova Scotia/Houston

1.4


&#160;


National Bank of Canada

1.4


&#160;


JPMorgan Chase &amp; Co

1.4


&#160;


Toronto Dominion Bank

1.4


&#160;


Bank of Montreal

1.3


&#160;


Goldman Sachs Group Inc/The

1.3


&#160;


&#160;

29.2

&#160;



</oef:LargestHoldingsTableTextBlock>
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      id="ixv-225781"
      unitRef="pure">0.142</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
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      unitRef="pure">0.038</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-225783"
      unitRef="pure">0.016</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000098000_TH_3_Member"
      decimals="INF"
      id="ixv-225784"
      unitRef="pure">0.014</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-225785"
      unitRef="pure">0.014</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
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      unitRef="pure">0.014</oef:PctOfNav>
    <oef:PctOfNav
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      unitRef="pure">0.014</oef:PctOfNav>
    <oef:PctOfNav
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    <oef:PctOfNav
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      unitRef="pure">0.013</oef:PctOfNav>
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    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-20031">2025-08-31</dei:DocumentPeriodEndDate>
    <oef:FundName contextRef="C000243069_ClassMember" id="ixv-20043">Fidelity&#xae; Conservative Income Bond Fund</oef:FundName>
    <oef:ClassName contextRef="C000243069_ClassMember" id="ixv-20046">Fidelity Advisor&#xae; Conservative Income Bond Fund Class Z</oef:ClassName>
    <dei:TradingSymbol contextRef="C000243069_ClassMember" id="ixv-20050">FCNYX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000243069_ClassMember" id="ixv-20069">This annual shareholder report contains information about Fidelity&#xae; Conservative Income Bond Fund for the period September 1, 2024 to August 31, 2025.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000243069_ClassMember" id="ixv-20071">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000243069_ClassMember" id="ixv-20076">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="C000243069_ClassMember" id="ixv-20078">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000243069_ClassMember" id="ixv-20081">1-877-208-0098</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000243069_ClassMember" id="ixv-20084">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000243069_ClassMember" id="ixv-20091">&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:45%; 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:24%; 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:30%; 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 $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:45%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Class Z&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:24%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$ &lt;/span&gt;21&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:30%; 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="C000243069_ClassMember"
      decimals="0"
      id="ixv-225791"
      unitRef="usd">21</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000243069_ClassMember"
      decimals="INF"
      id="ixv-225792"
      unitRef="pure">0.0020</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000243069_ClassMember" id="ixv-20133">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What affected the Fund's performance this period?&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;U.S. taxable investment-grade bonds posted a solid advance for the 12 months ending August 31, 2025, navigating tariff-related uncertainty since late 2024 but buoyed by relatively stable consumer inflation, a resilient economy and the expectation of policy interest-rate cuts by the U.S. Federal Reserve in the second half of 2025.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Against this backdrop, the fund's strategy of holding short-term debt in high-quality corporations contributed to performance versus the all-U.S.-Treasury benchmark for the fiscal year. Within corporates, debt holdings among financial institutions - especially banks - and industrial firms, particularly in the consumer cyclical and consumer non-cyclical segments, added notable value.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Non-benchmark exposure to asset-backed securities, primarily car loan debt, also meaningfully contributed.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity 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, a roughly 13% average allocation to cash - which the fund maintained for liquidity and solid interest return - detracted from relative performance.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;At period end, corporates made up about 53% of fund assets, down from roughly 54% a year ago. At the same time, exposure to U.S. Treasurys slightly increased, from 17% to 18% of assets, and the portfolio's out-of-benchmark position in ABS rose from approximately 14% of assets to 16% as of August 31.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:FactorsAffectingPerfTextBlock>
    <oef:LineGraphTableTextBlock contextRef="C000243069_ClassMember" id="ixv-20154">How did the Fund perform over the life of Fund?

 &#160;&#160;
CUMULATIVE PERFORMANCE
May 25, 2023 through August 31, 2025.
Initial investment of $10,000.
Class Z


$10,000

$10,156


$10,762



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


$10,000

$10,143


$10,706



Bloomberg U.S. Aggregate Bond Index


$10,000

$10,014


$10,744



&#160;

2023

2024

2025









&#160;
</oef:LineGraphTableTextBlock>
    <oef:LineGraphAndTableMeasureName contextRef="C000243069_LG_ClassMember_3YR" id="ixv-20173">&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="C000243069_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-225793"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000243069_ClassMember_AsOf_2024"
      decimals="0"
      id="ixv-225794"
      unitRef="usd">10156</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000243069_ClassMember_AsOf_2025"
      decimals="0"
      id="ixv-225795"
      unitRef="usd">10762</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000243069_LG_1_AdditionalIndexMember_3YR"
      id="ixv-20190">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg U.S. 3-6 Month Treasury Bill Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000243069_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-225796"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000243069_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-225797"
      unitRef="usd">10143</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000243069_1_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-225798"
      unitRef="usd">10706</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000243069_LG_2_AdditionalIndexMember_3YR"
      id="ixv-20207">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg U.S. Aggregate Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000243069_2_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-225799"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000243069_2_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-225800"
      unitRef="usd">10014</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000243069_2_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-225801"
      unitRef="usd">10744</oef:AccmVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000243069_ClassMember" id="ixv-20252">AVERAGE ANNUAL TOTAL RETURNS:

&#160;

1 Year

Life of Fund&#160;A


Class Z

4.77%

5.43%


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

4.60%


5.11%


Bloomberg U.S. Aggregate Bond Index

3.14%


4.62%




A&#160; &#160;From May 25, 2023

&#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="C000243069_NoLoadClassMember_1YR"
      decimals="INF"
      id="ixv-225802"
      unitRef="pure">0.0477</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000243069_NoLoadClassMember_2024-09-01_2025-08-31"
      decimals="INF"
      id="ixv-225803"
      unitRef="pure">0.0543</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000243069_0_AdditionalIndexMember_1YR"
      decimals="INF"
      id="ixv-225804"
      unitRef="pure">0.0460</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000243069_0_AdditionalIndexMember_LOC"
      decimals="INF"
      id="ixv-225805"
      unitRef="pure">0.0511</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000243069_1_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-225806"
      unitRef="pure">0.0314</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000243069_1_BBIndexMember_LOC"
      decimals="INF"
      id="ixv-225807"
      unitRef="pure">0.0462</oef:AvgAnnlRtrPct>
    <oef:PerfInceptionDate
      contextRef="C000243069_Perf_2023-05-25_ClassMember"
      id="ixv-20307">2023-05-25</oef:PerfInceptionDate>
    <oef:UpdPerfInfoLocationTextBlock contextRef="C000243069_ClassMember" id="ixv-20317">&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="C000243069_ClassMember" id="ixv-20329">&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="C000243069_ClassMember" id="ixv-20333">&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="C000243069_ClassMember" id="ixv-20339">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;Key Fund Statistics&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(as of August 31, 2025)&lt;/span&gt;&lt;/div&gt;
&lt;div&gt;&lt;span style="font-size:11px;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;table cellpadding="0" cellspacing="1" style="border-collapse:separate;border-style:none;margin:auto;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:63%; " valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:bold;"&gt;KEY FACTS&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt; &lt;span&gt;&#160;&lt;/span&gt;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fund Size&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;7,680,799,262&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;345&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;13,748,867&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;73&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="C000243069_InstantMember"
      decimals="0"
      id="ixv-225808"
      unitRef="usd">7680799262</us-gaap:AssetsNet>
    <oef:HoldingsCount
      contextRef="C000243069_InstantMember"
      decimals="INF"
      id="ixv-225809"
      unitRef="holding">345</oef:HoldingsCount>
    <oef:AdvisoryFeesPaidAmt
      contextRef="C000243069_ClassMember"
      decimals="0"
      id="ixv-225810"
      unitRef="usd">13748867</oef:AdvisoryFeesPaidAmt>
    <us-gaap:InvestmentCompanyPortfolioTurnover
      contextRef="C000243069_ClassMember"
      decimals="INF"
      id="ixv-225811"
      unitRef="pure">0.73</us-gaap:InvestmentCompanyPortfolioTurnover>
    <oef:HoldingsTableTextBlock contextRef="C000243069_ClassMember" id="ixv-20414">
&#160;
U.S. Government and U.S. Government Agency Obligations

18.0


AAA

15.6


AA

4.4


A

23.8


BBB

9.7


Not Rated

0.8


Short-Term Investments and Net Other Assets (Liabilities)

27.7




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

U.S. Government and U.S. Government Agency Obligations - 18.0


&#160;

AAA - 15.6&#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;

AA - 4.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

A - 23.8&#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 - 9.7&#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;

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


&#160;

Short-Term Investments and Net Other Assets (Liabilities) - 27.7


&#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;
&#160;
Corporate Bonds

38.2


U.S. Treasury Obligations

18.0


Asset-Backed Securities

16.1


Other Investments

0.0


Short-Term Investments and Net Other Assets (Liabilities)

27.7




ASSET ALLOCATION (% of Fund's net assets)


&#160;



&#160;

Corporate Bonds - 38.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

U.S. Treasury Obligations - 18.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Asset-Backed Securities - 16.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Other Investments - 0.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Short-Term Investments and Net Other Assets (Liabilities) - 27.7


&#160;






United States

85.1


Canada

3.5


United Kingdom

2.7


Germany

2.4


Netherlands

1.5


Japan

0.7


Ireland

0.7


France

0.7


Australia

0.6


Others

2.1




GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

United States - 85.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Canada - 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;

United Kingdom - 2.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Germany - 2.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Netherlands - 1.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

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


&#160;

Ireland - 0.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

France - 0.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Australia - 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;

Others - 2.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;




&#160;




&#160;
&#160;
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    <oef:LargestHoldingsTableTextBlock contextRef="C000243069_ClassMember" id="ixv-20797">TOP HOLDINGS(% of Fund's net assets)

&#160;

&#160;


US Treasury Bill

14.2


&#160;


US Treasury Notes

3.8


&#160;


Mitsubishi UFJ Trust &amp; Banking Corp/NY

1.6


&#160;


Mizuho Bank Ltd/New York NY

1.4


&#160;


Bank of Nova Scotia/Houston

1.4


&#160;


National Bank of Canada

1.4


&#160;


JPMorgan Chase &amp; Co

1.4


&#160;


Toronto Dominion Bank

1.4


&#160;


Bank of Montreal

1.3


&#160;


Goldman Sachs Group Inc/The

1.3


&#160;


&#160;

29.2

&#160;



</oef:LargestHoldingsTableTextBlock>
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    <oef:PctOfNav
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    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-20968">2025-08-31</dei:DocumentPeriodEndDate>
    <oef:FundName contextRef="C000243071_ClassMember" id="ixv-20980">Fidelity&#xae; Conservative Income Bond Fund</oef:FundName>
    <oef:ClassName contextRef="C000243071_ClassMember" id="ixv-20983">Fidelity Advisor&#xae; Conservative Income Bond Fund Class I</oef:ClassName>
    <dei:TradingSymbol contextRef="C000243071_ClassMember" id="ixv-20987">FCNWX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000243071_ClassMember" id="ixv-21006">This annual shareholder report contains information about Fidelity&#xae; Conservative Income Bond Fund for the period September 1, 2024 to August 31, 2025.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000243071_ClassMember" id="ixv-21008">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000243071_ClassMember" id="ixv-21013">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="C000243071_ClassMember" id="ixv-21015">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000243071_ClassMember" id="ixv-21018">1-877-208-0098</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000243071_ClassMember" id="ixv-21021">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000243071_ClassMember" id="ixv-21028">&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:45%; 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:24%; 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:30%; 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 $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:45%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Class I&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:24%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$ &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:30%; 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="C000243071_ClassMember"
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      id="ixv-225844"
      unitRef="usd">26</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000243071_ClassMember"
      decimals="INF"
      id="ixv-225845"
      unitRef="pure">0.0025</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000243071_ClassMember" id="ixv-21070">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What affected the Fund's performance this period?&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;U.S. taxable investment-grade bonds posted a solid advance for the 12 months ending August 31, 2025, navigating tariff-related uncertainty since late 2024 but buoyed by relatively stable consumer inflation, a resilient economy and the expectation of policy interest-rate cuts by the U.S. Federal Reserve in the second half of 2025.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Against this backdrop, the fund's strategy of holding short-term debt in high-quality corporations contributed to performance versus the all-U.S.-Treasury benchmark for the fiscal year. Within corporates, debt holdings among financial institutions - especially banks - and industrial firms, particularly in the consumer cyclical and consumer non-cyclical segments, added notable value.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Non-benchmark exposure to asset-backed securities, primarily car loan debt, also meaningfully contributed.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity 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, a roughly 13% average allocation to cash - which the fund maintained for liquidity and solid interest return - detracted from relative performance.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;At period end, corporates made up about 53% of fund assets, down from roughly 54% a year ago. At the same time, exposure to U.S. Treasurys slightly increased, from 17% to 18% of assets, and the portfolio's out-of-benchmark position in ABS rose from approximately 14% of assets to 16% as of August 31.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:FactorsAffectingPerfTextBlock>
    <oef:LineGraphTableTextBlock contextRef="C000243071_ClassMember" id="ixv-21091">How did the Fund perform over the life of Fund?

 &#160;&#160;
CUMULATIVE PERFORMANCE
May 25, 2023 through August 31, 2025.
Initial investment of $10,000.
Class I


$10,000

$10,155


$10,756



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


$10,000

$10,143


$10,706



Bloomberg U.S. Aggregate Bond Index


$10,000

$10,014


$10,744



&#160;

2023

2024

2025









&#160;
</oef:LineGraphTableTextBlock>
    <oef:LineGraphAndTableMeasureName contextRef="C000243071_LG_ClassMember_3YR" id="ixv-21110">&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="C000243071_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-225846"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000243071_ClassMember_AsOf_2024"
      decimals="0"
      id="ixv-225847"
      unitRef="usd">10155</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000243071_ClassMember_AsOf_2025"
      decimals="0"
      id="ixv-225848"
      unitRef="usd">10756</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000243071_LG_1_AdditionalIndexMember_3YR"
      id="ixv-21127">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg U.S. 3-6 Month Treasury Bill Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000243071_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-225849"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000243071_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-225850"
      unitRef="usd">10143</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000243071_1_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-225851"
      unitRef="usd">10706</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000243071_LG_2_AdditionalIndexMember_3YR"
      id="ixv-21144">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg U.S. Aggregate Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000243071_2_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-225852"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000243071_2_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-225853"
      unitRef="usd">10014</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000243071_2_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-225854"
      unitRef="usd">10744</oef:AccmVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000243071_ClassMember" id="ixv-21189">AVERAGE ANNUAL TOTAL RETURNS:

&#160;

1 Year

Life of Fund&#160;A


Class I

4.72%

5.38%


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

4.60%


5.11%


Bloomberg U.S. Aggregate Bond Index

3.14%


4.62%




A&#160; &#160;From May 25, 2023

&#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="C000243071_NoLoadClassMember_1YR"
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      id="ixv-225855"
      unitRef="pure">0.0472</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
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      id="ixv-225856"
      unitRef="pure">0.0538</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
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      id="ixv-225857"
      unitRef="pure">0.0460</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
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      decimals="INF"
      id="ixv-225858"
      unitRef="pure">0.0511</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000243071_1_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-225859"
      unitRef="pure">0.0314</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000243071_1_BBIndexMember_LOC"
      decimals="INF"
      id="ixv-225860"
      unitRef="pure">0.0462</oef:AvgAnnlRtrPct>
    <oef:PerfInceptionDate
      contextRef="C000243071_Perf_2023-05-25_ClassMember"
      id="ixv-21244">2023-05-25</oef:PerfInceptionDate>
    <oef:UpdPerfInfoLocationTextBlock contextRef="C000243071_ClassMember" id="ixv-21254">&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="C000243071_ClassMember" id="ixv-21266">&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="C000243071_ClassMember" id="ixv-21270">&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="C000243071_ClassMember" id="ixv-21276">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;Key Fund Statistics&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(as of August 31, 2025)&lt;/span&gt;&lt;/div&gt;
&lt;div&gt;&lt;span style="font-size:11px;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;table cellpadding="0" cellspacing="1" style="border-collapse:separate;border-style:none;margin:auto;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:63%; " valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:bold;"&gt;KEY FACTS&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt; &lt;span&gt;&#160;&lt;/span&gt;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fund Size&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;7,680,799,262&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;345&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;13,748,867&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;73&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="C000243071_InstantMember"
      decimals="0"
      id="ixv-225861"
      unitRef="usd">7680799262</us-gaap:AssetsNet>
    <oef:HoldingsCount
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    <oef:AdvisoryFeesPaidAmt
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    <us-gaap:InvestmentCompanyPortfolioTurnover
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      id="ixv-225864"
      unitRef="pure">0.73</us-gaap:InvestmentCompanyPortfolioTurnover>
    <oef:HoldingsTableTextBlock contextRef="C000243071_ClassMember" id="ixv-21351">
&#160;
U.S. Government and U.S. Government Agency Obligations

18.0


AAA

15.6


AA

4.4


A

23.8


BBB

9.7


Not Rated

0.8


Short-Term Investments and Net Other Assets (Liabilities)

27.7




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

U.S. Government and U.S. Government Agency Obligations - 18.0


&#160;

AAA - 15.6&#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;

AA - 4.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

A - 23.8&#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 - 9.7&#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;

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


&#160;

Short-Term Investments and Net Other Assets (Liabilities) - 27.7


&#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;
&#160;
Corporate Bonds

38.2


U.S. Treasury Obligations

18.0


Asset-Backed Securities

16.1


Other Investments

0.0


Short-Term Investments and Net Other Assets (Liabilities)

27.7




ASSET ALLOCATION (% of Fund's net assets)


&#160;



&#160;

Corporate Bonds - 38.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

U.S. Treasury Obligations - 18.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Asset-Backed Securities - 16.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Other Investments - 0.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Short-Term Investments and Net Other Assets (Liabilities) - 27.7


&#160;






United States

85.1


Canada

3.5


United Kingdom

2.7


Germany

2.4


Netherlands

1.5


Japan

0.7


Ireland

0.7


France

0.7


Australia

0.6


Others

2.1




GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

United States - 85.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Canada - 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;

United Kingdom - 2.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Germany - 2.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Netherlands - 1.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

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


&#160;

Ireland - 0.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

France - 0.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Australia - 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;

Others - 2.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;




&#160;




&#160;
&#160;
</oef:HoldingsTableTextBlock>
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    <oef:LargestHoldingsTableTextBlock contextRef="C000243071_ClassMember" id="ixv-21734">TOP HOLDINGS(% of Fund's net assets)

&#160;

&#160;


US Treasury Bill

14.2


&#160;


US Treasury Notes

3.8


&#160;


Mitsubishi UFJ Trust &amp; Banking Corp/NY

1.6


&#160;


Mizuho Bank Ltd/New York NY

1.4


&#160;


Bank of Nova Scotia/Houston

1.4


&#160;


National Bank of Canada

1.4


&#160;


JPMorgan Chase &amp; Co

1.4


&#160;


Toronto Dominion Bank

1.4


&#160;


Bank of Montreal

1.3


&#160;


Goldman Sachs Group Inc/The

1.3


&#160;


&#160;

29.2

&#160;



</oef:LargestHoldingsTableTextBlock>
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      id="ixv-225887"
      unitRef="pure">0.142</oef:PctOfNav>
    <oef:PctOfNav
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    <oef:PctOfNav
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      unitRef="pure">0.016</oef:PctOfNav>
    <oef:PctOfNav
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      id="ixv-225890"
      unitRef="pure">0.014</oef:PctOfNav>
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      decimals="INF"
      id="ixv-225891"
      unitRef="pure">0.014</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000243071_TH_5_Member"
      decimals="INF"
      id="ixv-225892"
      unitRef="pure">0.014</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000243071_TH_6_Member"
      decimals="INF"
      id="ixv-225893"
      unitRef="pure">0.014</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000243071_TH_7_Member"
      decimals="INF"
      id="ixv-225894"
      unitRef="pure">0.014</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000243071_TH_8_Member"
      decimals="INF"
      id="ixv-225895"
      unitRef="pure">0.013</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000243071_TH_9_Member"
      decimals="INF"
      id="ixv-225896"
      unitRef="pure">0.013</oef:PctOfNav>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-21905">2025-08-31</dei:DocumentPeriodEndDate>
    <oef:FundName contextRef="C000243070_ClassMember" id="ixv-21917">Fidelity&#xae; Conservative Income Bond Fund</oef:FundName>
    <oef:ClassName contextRef="C000243070_ClassMember" id="ixv-21920">Fidelity Advisor&#xae; Conservative Income Bond Fund Class A</oef:ClassName>
    <dei:TradingSymbol contextRef="C000243070_ClassMember" id="ixv-21924">FCNQX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000243070_ClassMember" id="ixv-21943">This annual shareholder report contains information about Fidelity&#xae; Conservative Income Bond Fund for the period September 1, 2024 to August 31, 2025.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000243070_ClassMember" id="ixv-21945">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000243070_ClassMember" id="ixv-21950">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="C000243070_ClassMember" id="ixv-21952">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000243070_ClassMember" id="ixv-21955">1-877-208-0098</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000243070_ClassMember" id="ixv-21958">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000243070_ClassMember" id="ixv-21965">&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:45%; 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:24%; 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:30%; 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 $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:45%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Class A&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:24%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$ &lt;/span&gt;46&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:30%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;0.45&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:ExpensesTextBlock>
    <oef:ExpensesPaidAmt
      contextRef="C000243070_ClassMember"
      decimals="0"
      id="ixv-225897"
      unitRef="usd">46</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000243070_ClassMember"
      decimals="INF"
      id="ixv-225898"
      unitRef="pure">0.0045</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000243070_ClassMember" id="ixv-22007">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What affected the Fund's performance this period?&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;U.S. taxable investment-grade bonds posted a solid advance for the 12 months ending August 31, 2025, navigating tariff-related uncertainty since late 2024 but buoyed by relatively stable consumer inflation, a resilient economy and the expectation of policy interest-rate cuts by the U.S. Federal Reserve in the second half of 2025.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Against this backdrop, the fund's strategy of holding short-term debt in high-quality corporations contributed to performance versus the all-U.S.-Treasury benchmark for the fiscal year. Within corporates, debt holdings among financial institutions - especially banks - and industrial firms, particularly in the consumer cyclical and consumer non-cyclical segments, added notable value.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Non-benchmark exposure to asset-backed securities, primarily car loan debt, also meaningfully contributed.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity 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, a roughly 13% average allocation to cash - which the fund maintained for liquidity and solid interest return - detracted from relative performance.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;At period end, corporates made up about 53% of fund assets, down from roughly 54% a year ago. At the same time, exposure to U.S. Treasurys slightly increased, from 17% to 18% of assets, and the portfolio's out-of-benchmark position in ABS rose from approximately 14% of assets to 16% as of August 31.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:FactorsAffectingPerfTextBlock>
    <oef:LineGraphTableTextBlock contextRef="C000243070_ClassMember" id="ixv-22028">How did the Fund perform over the life of Fund?

 &#160;&#160;
CUMULATIVE PERFORMANCE
May 25, 2023 through August 31, 2025.
Initial investment of $10,000&#160;and the current sales charge was paid.
Class A


$9,850

$9,998


$10,569



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


$10,000

$10,143


$10,706



Bloomberg U.S. Aggregate Bond Index


$10,000

$10,014


$10,744



&#160;

2023

2024

2025









&#160;
</oef:LineGraphTableTextBlock>
    <oef:LineGraphAndTableMeasureName contextRef="C000243070_LG_ClassMember_3YR" id="ixv-22049">&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="C000243070_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-225899"
      unitRef="usd">9850</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000243070_ClassMember_AsOf_2024"
      decimals="0"
      id="ixv-225900"
      unitRef="usd">9998</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000243070_ClassMember_AsOf_2025"
      decimals="0"
      id="ixv-225901"
      unitRef="usd">10569</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000243070_LG_1_AdditionalIndexMember_3YR"
      id="ixv-22066">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg U.S. 3-6 Month Treasury Bill Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000243070_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-225902"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000243070_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-225903"
      unitRef="usd">10143</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000243070_1_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-225904"
      unitRef="usd">10706</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000243070_LG_2_AdditionalIndexMember_3YR"
      id="ixv-22083">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg U.S. Aggregate Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AccmVal
      contextRef="C000243070_2_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-225905"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000243070_2_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-225906"
      unitRef="usd">10014</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000243070_2_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-225907"
      unitRef="usd">10744</oef:AccmVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000243070_ClassMember" id="ixv-22128">AVERAGE ANNUAL TOTAL RETURNS:

&#160;

1 Year

Life of Fund&#160;A


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

2.94%

4.47%


Class A (without 1.50% sales charge)

4.51%

5.17%


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

4.60%


5.11%


Bloomberg U.S. Aggregate Bond Index

3.14%


4.62%




A&#160; &#160;From May 25, 2023

&#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="C000243070_ClassMember_1YR"
      decimals="INF"
      id="ixv-225908"
      unitRef="pure">0.0294</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000243070_ClassMember_2024-09-01_2025-08-31"
      decimals="INF"
      id="ixv-225909"
      unitRef="pure">0.0447</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000243070_NoLoadClassMember_1YR"
      decimals="INF"
      id="ixv-225910"
      unitRef="pure">0.0451</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000243070_NoLoadClassMember_2024-09-01_2025-08-31"
      decimals="INF"
      id="ixv-225911"
      unitRef="pure">0.0517</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000243070_0_AdditionalIndexMember_1YR"
      decimals="INF"
      id="ixv-225912"
      unitRef="pure">0.0460</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000243070_0_AdditionalIndexMember_LOC"
      decimals="INF"
      id="ixv-225913"
      unitRef="pure">0.0511</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000243070_1_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-225914"
      unitRef="pure">0.0314</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000243070_1_BBIndexMember_LOC"
      decimals="INF"
      id="ixv-225915"
      unitRef="pure">0.0462</oef:AvgAnnlRtrPct>
    <oef:PerfInceptionDate
      contextRef="C000243070_Perf_2023-05-25_ClassMember"
      id="ixv-22194">2023-05-25</oef:PerfInceptionDate>
    <oef:UpdPerfInfoLocationTextBlock contextRef="C000243070_ClassMember" id="ixv-22204">&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="C000243070_ClassMember" id="ixv-22216">&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="C000243070_ClassMember" id="ixv-22220">&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="C000243070_ClassMember" id="ixv-22226">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;Key Fund Statistics&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(as of August 31, 2025)&lt;/span&gt;&lt;/div&gt;
&lt;div&gt;&lt;span style="font-size:11px;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;table cellpadding="0" cellspacing="1" style="border-collapse:separate;border-style:none;margin:auto;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:63%; " valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:bold;"&gt;KEY FACTS&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt; &lt;span&gt;&#160;&lt;/span&gt;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fund Size&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;7,680,799,262&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;345&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;13,748,867&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;73&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>
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&#160;
U.S. Government and U.S. Government Agency Obligations

18.0


AAA

15.6


AA

4.4


A

23.8


BBB

9.7


Not Rated

0.8


Short-Term Investments and Net Other Assets (Liabilities)

27.7




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

U.S. Government and U.S. Government Agency Obligations - 18.0


&#160;

AAA - 15.6&#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;

AA - 4.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

A - 23.8&#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 - 9.7&#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;

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


&#160;

Short-Term Investments and Net Other Assets (Liabilities) - 27.7


&#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;
&#160;
Corporate Bonds

38.2


U.S. Treasury Obligations

18.0


Asset-Backed Securities

16.1


Other Investments

0.0


Short-Term Investments and Net Other Assets (Liabilities)

27.7




ASSET ALLOCATION (% of Fund's net assets)


&#160;



&#160;

Corporate Bonds - 38.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

U.S. Treasury Obligations - 18.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Asset-Backed Securities - 16.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Other Investments - 0.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Short-Term Investments and Net Other Assets (Liabilities) - 27.7


&#160;






United States

85.1


Canada

3.5


United Kingdom

2.7


Germany

2.4


Netherlands

1.5


Japan

0.7


Ireland

0.7


France

0.7


Australia

0.6


Others

2.1




GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

United States - 85.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Canada - 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;

United Kingdom - 2.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Germany - 2.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Netherlands - 1.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

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


&#160;

Ireland - 0.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

France - 0.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Australia - 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;

Others - 2.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;




&#160;




&#160;
&#160;
</oef:HoldingsTableTextBlock>
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    <oef:LargestHoldingsTableTextBlock contextRef="C000243070_ClassMember" id="ixv-22684">TOP HOLDINGS(% of Fund's net assets)

&#160;

&#160;


US Treasury Bill

14.2


&#160;


US Treasury Notes

3.8


&#160;


Mitsubishi UFJ Trust &amp; Banking Corp/NY

1.6


&#160;


Mizuho Bank Ltd/New York NY

1.4


&#160;


Bank of Nova Scotia/Houston

1.4


&#160;


National Bank of Canada

1.4


&#160;


JPMorgan Chase &amp; Co

1.4


&#160;


Toronto Dominion Bank

1.4


&#160;


Bank of Montreal

1.3


&#160;


Goldman Sachs Group Inc/The

1.3


&#160;


&#160;

29.2

&#160;



</oef:LargestHoldingsTableTextBlock>
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      id="ixv-225942"
      unitRef="pure">0.142</oef:PctOfNav>
    <oef:PctOfNav
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      id="ixv-225943"
      unitRef="pure">0.038</oef:PctOfNav>
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      unitRef="pure">0.016</oef:PctOfNav>
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      unitRef="pure">0.014</oef:PctOfNav>
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      decimals="INF"
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      unitRef="pure">0.014</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
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      unitRef="pure">0.014</oef:PctOfNav>
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</xbrl>
