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    <unit id="usd">
        <measure>iso4217:USD</measure>
    </unit>
    <unit id="pure">
        <measure>pure</measure>
    </unit>
    <unit id="holding">
        <measure>shares</measure>
    </unit>
    <dei:DocumentType contextRef="Trust" id="ixv-97141">485BPOS</dei:DocumentType>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-97142">2025-10-30</dei:DocumentPeriodEndDate>
    <dei:AmendmentFlag contextRef="Trust" id="ixv-97143">false</dei:AmendmentFlag>
    <dei:EntityCentralIndexKey contextRef="Trust" id="ixv-97144">0000035315</dei:EntityCentralIndexKey>
    <dei:EntityInvCompanyType contextRef="Trust" id="ixv-97145">N-1A</dei:EntityInvCompanyType>
    <dei:EntityRegistrantName contextRef="Trust" id="ixv-97146">Fidelity Salem Street Trust</dei:EntityRegistrantName>
    <oef:RiskReturnHeading contextRef="Pid_S000007007_contentCd_STP-PRO" id="ixv-214">


     Fund Summary

     Fund /Class:
     Fidelity&#xae; Short-Term Bond Fund
     /Fidelity&#xae; Short-Term Bond Fund

   </oef:RiskReturnHeading>
    <oef:ObjectiveHeading contextRef="Pid_S000007007_contentCd_STP-PRO" id="ixv-227">


     Investment Objective


   </oef:ObjectiveHeading>
    <oef:ObjectivePrimaryTextBlock contextRef="Pid_S000007007_contentCd_STP-PRO" id="ixv-232">


     Fidelity&#xae; Short-Term Bond Fund seeks to obtain a high level of current income consistent with preservation of capital.


   </oef:ObjectivePrimaryTextBlock>
    <oef:ExpenseHeading contextRef="Pid_S000007007_contentCd_STP-PRO" id="ixv-237">


     Fee Table


   </oef:ExpenseHeading>
    <oef:ExpenseNarrativeTextBlock contextRef="Pid_S000007007_contentCd_STP-PRO" id="ixv-243">


     The following table describes the fees and expenses that may be incurred when you buy, hold, and sell shares of the fund. You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and examples below.

   </oef:ExpenseNarrativeTextBlock>
    <oef:ShareholderFeesCaption contextRef="Pid_S000007007_contentCd_STP-PRO" id="ixv-254">


     Shareholder fees


   </oef:ShareholderFeesCaption>
    <oef:ShareholderFeeOther
      contextRef="Pid_S000007007_contentCd_STP-PRO"
      decimals="0"
      id="ixv-101228"
      unitRef="usd">0</oef:ShareholderFeeOther>
    <oef:OperatingExpensesCaption contextRef="Pid_S000007007_contentCd_STP-PRO" id="ixv-269">


     Annual Operating Expenses


   </oef:OperatingExpensesCaption>
    <oef:ManagementFeesOverAssets
      contextRef="Pid_S000007007_Cid_C000019128"
      decimals="6"
      id="ixv-101229"
      unitRef="pure">0.0020</oef:ManagementFeesOverAssets>
    <oef:DistributionAndService12b1FeesOverAssets
      contextRef="Pid_S000007007_Cid_C000019128"
      decimals="6"
      id="ixv-101230"
      unitRef="pure">0</oef:DistributionAndService12b1FeesOverAssets>
    <oef:OtherExpensesOverAssets
      contextRef="Pid_S000007007_Cid_C000019128"
      decimals="6"
      id="ixv-101231"
      unitRef="pure">0.0010</oef:OtherExpensesOverAssets>
    <oef:ExpensesOverAssets
      contextRef="Pid_S000007007_Cid_C000019128"
      decimals="6"
      id="ixv-101232"
      unitRef="pure">0.0030</oef:ExpensesOverAssets>
    <oef:ExpenseExampleNarrativeTextBlock contextRef="Pid_S000007007_contentCd_STP-PRO" id="ixv-316">


     This
     example

     helps compare the cost of investing in the fund with the cost of investing in other funds.

     Let's say, hypothetically, that the annual return for shares of the fund is 5% and that the fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated:

   </oef:ExpenseExampleNarrativeTextBlock>
    <oef:ExpenseExampleYear01
      contextRef="Pid_S000007007_Cid_C000019128"
      decimals="0"
      id="ixv-101233"
      unitRef="usd">31</oef:ExpenseExampleYear01>
    <oef:ExpenseExampleYear03
      contextRef="Pid_S000007007_Cid_C000019128"
      decimals="0"
      id="ixv-101234"
      unitRef="usd">97</oef:ExpenseExampleYear03>
    <oef:ExpenseExampleYear05
      contextRef="Pid_S000007007_Cid_C000019128"
      decimals="0"
      id="ixv-101235"
      unitRef="usd">169</oef:ExpenseExampleYear05>
    <oef:ExpenseExampleYear10
      contextRef="Pid_S000007007_Cid_C000019128"
      decimals="0"
      id="ixv-101236"
      unitRef="usd">381</oef:ExpenseExampleYear10>
    <oef:PortfolioTurnoverHeading contextRef="Pid_S000007007_contentCd_STP-PRO" id="ixv-373">


     Portfolio Turnover


   </oef:PortfolioTurnoverHeading>
    <oef:PortfolioTurnoverTextBlock contextRef="Pid_S000007007_contentCd_STP-PRO" id="ixv-378">


     The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was



       59


     % of the average value of its portfolio.


   </oef:PortfolioTurnoverTextBlock>
    <oef:PortfolioTurnoverRate
      contextRef="Pid_S000007007_contentCd_STP-PRO"
      decimals="4"
      id="ixv-101237"
      unitRef="pure">0.59</oef:PortfolioTurnoverRate>
    <oef:StrategyHeading contextRef="Pid_S000007007_contentCd_STP-PRO" id="ixv-387">


     Principal Investment Strategies


   </oef:StrategyHeading>
    <oef:StrategyNarrativeTextBlock contextRef="Pid_S000007007_contentCd_STP-PRO" id="ixv-392">




        Normally investing at least 80% of assets in investment-grade debt securities (those of medium and high quality) of all types and repurchase agreements for those securities.

     Debt securities are used by issuers to borrow money. The issuer usually pays a fixed, variable, or floating rate of interest, and must repay the amount borrowed, usually at the maturity of the security. Debt securities include corporate bonds, government securities (including Treasury securities), repurchase agreements, money market securities, mortgage and other asset-backed securities, loans and loan participations, and other securities, such as hybrids and synthetic securities, believed to have debt-like characteristics (e.g., securities classified as Tier 2 Regulatory capital, securities that rank above share capital in an insolvency waterfall, securities with maturity dates and non-cancellable interest payment structures).&#160;
     Investment grade securities in which the fund invests include securities or issuers rated at least BBB- or its equivalent by at least one nationally recognized statistical ratings organization (NRSRO), or, if unrated, determined by the Adviser to be of comparable quality.
     A repurchase agreement is an agreement to buy a security at one price and a simultaneous agreement to sell it back at an agreed-upon price.
     Effective December 11, 2025, derivative instruments that provide investment exposure to the investments above or exposure to one or more market risk factors associated with such investments are included in the fund's 80% policy, consistent with the fund's investment policies and limitations with respect to investments in derivatives.

      &#160;
      Managing the fund to have similar overall interest rate risk to the Bloomberg U.S. 1-3 Year Government/Credit Bond Index.
      Normally maintaining a dollar-weighted average maturity of three years or less.
      Allocating assets across different market sectors and maturities.
      Investing in domestic and foreign issuers.
      Analyzing the credit quality of the issuer, security-specific features, current and potential future valuation, and trading opportunities to select investments.
      Engaging in transactions that have a leveraging effect on the fund, including investments in derivatives - such as swaps (interest rate, total return, and credit default), options, and futures contracts - and forward-settling securities, to adjust the fund's risk exposure.
      Investing in Fidelity's Central funds (specialized investment vehicles used by Fidelity&#xae; funds to invest in particular security types or investment disciplines) consistent with the asset classes discussed above.


   </oef:StrategyNarrativeTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000007007_contentCd_STP-PRO_RiskMember_InterestRateChangesMember"
      id="ixv-429">



      Interest Rate Changes.

     Interest rate increases can cause the price of a debt security to decrease.

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000007007_contentCd_STP-PRO_RiskMember_ForeignExposureMember"
      id="ixv-438">



      Foreign Exposure.

     Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market.

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000007007_contentCd_STP-PRO_RiskMember_PrepaymentMember"
      id="ixv-447">



      Prepayment.

     The ability of an issuer of a debt security to repay principal prior to a security's maturity can cause greater price volatility if interest rates change.

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000007007_contentCd_STP-PRO_RiskMember_IssuerSpecificChangesMember"
      id="ixv-456">



      Issuer-Specific Changes.

     The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole.
     A decline in the credit quality of an issuer or a provider of credit support (such as guarantees) or a maturity-shortening structure (such as demand and put features) for a security can cause the price of a security to decrease.

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000007007_contentCd_STP-PRO_RiskMember_LeverageRiskMember"
      id="ixv-471">



      Leverage Risk.

     Leverage can increase market exposure, magnify investment risks, and cause losses to be realized more quickly.



   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000007007_contentCd_STP-PRO_RiskMember_RiskNotInsuredDepositoryInstitutionMember"
      id="ixv-481">


     An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency

     .


   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000007007_contentCd_STP-PRO_RiskMember_RiskLoseMoneyMember"
      id="ixv-489">


     &#160;

     You could lose money by investing in the fund.


   </oef:RiskTextBlock>
    <oef:BarChartAndPerformanceTableHeading contextRef="Pid_S000007007_contentCd_STP-PRO" id="ixv-498">


     Performance


   </oef:BarChartAndPerformanceTableHeading>
    <oef:PerformanceNarrativeTextBlock contextRef="Pid_S000007007_contentCd_STP-PRO" id="ixv-503">



       The following information is intended to help you understand the risks of investing in the fund.


      The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time.



     The additional index has characteristics relevant to the fund's investment strategies. Index descriptions appear

     in the "Additional Index Information" section of the prospectus.



      Past performance (before and after taxes) is not an indication of future performance.


     Visit



      www.fidelity.com


     for more recent performance information.

   </oef:PerformanceNarrativeTextBlock>
    <oef:PerformanceInformationIllustratesVariabilityOfReturns contextRef="Pid_S000007007_contentCd_STP-PRO" id="ixv-509">

      The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time.

     </oef:PerformanceInformationIllustratesVariabilityOfReturns>
    <oef:PerformancePastDoesNotIndicateFuture contextRef="Pid_S000007007_contentCd_STP-PRO" id="ixv-518">

      Past performance (before and after taxes) is not an indication of future performance.

     </oef:PerformancePastDoesNotIndicateFuture>
    <oef:PerformanceAvailabilityWebSiteAddress contextRef="Pid_S000007007_contentCd_STP-PRO" id="ixv-524">

      www.fidelity.com
     </oef:PerformanceAvailabilityWebSiteAddress>
    <oef:BarChartHeading contextRef="Pid_S000007007_contentCd_STP-PRO" id="ixv-529">


     Year-by-Year Returns

   </oef:BarChartHeading>
    <oef:AnnlRtrPct
      contextRef="Pid_S000007007_Cid_C000019128_2015"
      decimals="INF"
      id="ixv-101238"
      unitRef="pure">0.0067</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000007007_Cid_C000019128_2016"
      decimals="INF"
      id="ixv-101239"
      unitRef="pure">0.0145</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000007007_Cid_C000019128_2017"
      decimals="INF"
      id="ixv-101240"
      unitRef="pure">0.0115</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000007007_Cid_C000019128_2018"
      decimals="INF"
      id="ixv-101241"
      unitRef="pure">0.0119</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000007007_Cid_C000019128_2019"
      decimals="INF"
      id="ixv-101242"
      unitRef="pure">0.0420</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000007007_Cid_C000019128_2020"
      decimals="INF"
      id="ixv-101243"
      unitRef="pure">0.0370</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000007007_Cid_C000019128_2021"
      decimals="INF"
      id="ixv-101244"
      unitRef="pure">-0.0073</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000007007_Cid_C000019128_2022"
      decimals="INF"
      id="ixv-101245"
      unitRef="pure">-0.0362</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000007007_Cid_C000019128_2023"
      decimals="INF"
      id="ixv-101246"
      unitRef="pure">0.0534</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000007007_Cid_C000019128_2024"
      decimals="INF"
      id="ixv-101247"
      unitRef="pure">0.0471</oef:AnnlRtrPct>
    <oef:HighestQuarterlyReturnLabel contextRef="Pid_S000007007_contentCd_STP-PRO" id="ixv-640">
          &#160;&#160;&#160;Highest Quarter Return
        </oef:HighestQuarterlyReturnLabel>
    <oef:BarChartHighestQuarterlyReturn
      contextRef="Pid_S000007007_contentCd_STP-PRO"
      decimals="4"
      id="ixv-101248"
      unitRef="pure">0.0298</oef:BarChartHighestQuarterlyReturn>
    <oef:BarChartHighestQuarterlyReturnDate contextRef="Pid_S000007007_contentCd_STP-PRO" id="ixv-650">2020-06-30</oef:BarChartHighestQuarterlyReturnDate>
    <oef:LowestQuarterlyReturnLabel contextRef="Pid_S000007007_contentCd_STP-PRO" id="ixv-655">
          &#160;&#160;&#160;Lowest Quarter Return
        </oef:LowestQuarterlyReturnLabel>
    <oef:BarChartLowestQuarterlyReturn
      contextRef="Pid_S000007007_contentCd_STP-PRO"
      decimals="4"
      id="ixv-101249"
      unitRef="pure">-0.0250</oef:BarChartLowestQuarterlyReturn>
    <oef:BarChartLowestQuarterlyReturnDate contextRef="Pid_S000007007_contentCd_STP-PRO" id="ixv-666">2022-03-31</oef:BarChartLowestQuarterlyReturnDate>
    <oef:YearToDateReturnLabel contextRef="Pid_S000007007_contentCd_STP-PRO" id="ixv-671">
          &#160;&#160;&#160;Year-to-Date Return
        </oef:YearToDateReturnLabel>
    <oef:BarChartYearToDateReturn
      contextRef="Pid_S000007007_contentCd_STP-PRO"
      decimals="4"
      id="ixv-101250"
      unitRef="pure">0.0430</oef:BarChartYearToDateReturn>
    <oef:BarChartYearToDateReturnDate contextRef="Pid_S000007007_contentCd_STP-PRO" id="ixv-681">2025-09-30</oef:BarChartYearToDateReturnDate>
    <oef:PerformanceTableHeading contextRef="Pid_S000007007_contentCd_STP-PRO" id="ixv-686">


     Average Annual Returns


   </oef:PerformanceTableHeading>
    <oef:PerformanceTableNarrativeTextBlock contextRef="Pid_S000007007_contentCd_STP-PRO" id="ixv-691">




      After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes.



     Actual after-tax returns may differ depending on your individual circumstances.



      The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan).





      Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.




   </oef:PerformanceTableNarrativeTextBlock>
    <oef:PerformanceTableUsesHighestFederalRate contextRef="Pid_S000007007_contentCd_STP-PRO" id="ixv-694">

      After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes.

     </oef:PerformanceTableUsesHighestFederalRate>
    <oef:PerformanceTableNotRelevantToTaxDeferred contextRef="Pid_S000007007_contentCd_STP-PRO" id="ixv-701">

      The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan).

     </oef:PerformanceTableNotRelevantToTaxDeferred>
    <oef:PerformanceTableExplanationAfterTaxHigher contextRef="Pid_S000007007_contentCd_STP-PRO" id="ixv-706">

      Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

     </oef:PerformanceTableExplanationAfterTaxHigher>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000007007_Cid_C000019128_ReturnBeforeTaxes_01"
      id="ixv-751">
         Return Before Taxes
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007007_Cid_C000019128_ReturnBeforeTaxes_01"
      decimals="4"
      id="ixv-101251"
      unitRef="pure">0.0471</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007007_Cid_C000019128_ReturnBeforeTaxes_05"
      decimals="4"
      id="ixv-101252"
      unitRef="pure">0.0182</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007007_Cid_C000019128_ReturnBeforeTaxes_10"
      decimals="4"
      id="ixv-101253"
      unitRef="pure">0.0177</oef:AvgAnnlRtrPct>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000007007_Cid_C000019128_AfterTaxesOnDistributions_01"
      id="ixv-766">
         Return After Taxes on Distributions
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007007_Cid_C000019128_AfterTaxesOnDistributions_01"
      decimals="4"
      id="ixv-101254"
      unitRef="pure">0.0304</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007007_Cid_C000019128_AfterTaxesOnDistributions_05"
      decimals="4"
      id="ixv-101255"
      unitRef="pure">0.0085</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007007_Cid_C000019128_AfterTaxesOnDistributions_10"
      decimals="4"
      id="ixv-101256"
      unitRef="pure">0.0098</oef:AvgAnnlRtrPct>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000007007_Cid_C000019128_AfterTaxesOnDistributionsAndSales_01"
      id="ixv-781">
         Return After Taxes on Distributions and Sale of Fund Shares
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007007_Cid_C000019128_AfterTaxesOnDistributionsAndSales_01"
      decimals="4"
      id="ixv-101257"
      unitRef="pure">0.0279</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007007_Cid_C000019128_AfterTaxesOnDistributionsAndSales_05"
      decimals="4"
      id="ixv-101258"
      unitRef="pure">0.0099</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007007_Cid_C000019128_AfterTaxesOnDistributionsAndSales_10"
      decimals="4"
      id="ixv-101259"
      unitRef="pure">0.0102</oef:AvgAnnlRtrPct>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000007007_Indexid_LB013_contentCd_STP-PRO_01"
      id="ixv-797">
         Bloomberg U.S. 1-3 Year Government/Credit Bond Index
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007007_Indexid_LB013_contentCd_STP-PRO_01"
      decimals="4"
      id="ixv-101260"
      unitRef="pure">0.0436</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007007_Indexid_LB013_contentCd_STP-PRO_05"
      decimals="4"
      id="ixv-101261"
      unitRef="pure">0.0158</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007007_Indexid_LB013_contentCd_STP-PRO_10"
      decimals="4"
      id="ixv-101262"
      unitRef="pure">0.0163</oef:AvgAnnlRtrPct>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000007007_Indexid_LB001_contentCd_STP-PRO_01"
      id="ixv-822">
         Bloomberg U.S. Aggregate Bond Index
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007007_Indexid_LB001_contentCd_STP-PRO_01"
      decimals="4"
      id="ixv-101263"
      unitRef="pure">0.0125</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007007_Indexid_LB001_contentCd_STP-PRO_05"
      decimals="4"
      id="ixv-101264"
      unitRef="pure">-0.0033</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007007_Indexid_LB001_contentCd_STP-PRO_10"
      decimals="4"
      id="ixv-101265"
      unitRef="pure">0.0135</oef:AvgAnnlRtrPct>
    <oef:RiskReturnHeading
      contextRef="Pid_S000007007_contentCd_ASTP-PRO"
      id="ixv-2937">


     Fund Summary

     Fund /Class:
     Fidelity&#xae; Short-Term Bond Fund
     /Fidelity Advisor&#xae; Short-Term Bond Fund A, M, C, I, Z &#160;

   </oef:RiskReturnHeading>
    <oef:ObjectiveHeading
      contextRef="Pid_S000007007_contentCd_ASTP-PRO"
      id="ixv-2952">


     Investment Objective


   </oef:ObjectiveHeading>
    <oef:ObjectivePrimaryTextBlock
      contextRef="Pid_S000007007_contentCd_ASTP-PRO"
      id="ixv-2957">


     Fidelity&#xae; Short-Term Bond Fund seeks to obtain a high level of current income consistent with preservation of capital.


   </oef:ObjectivePrimaryTextBlock>
    <oef:ExpenseHeading
      contextRef="Pid_S000007007_contentCd_ASTP-PRO"
      id="ixv-2962">


     Fee Table


   </oef:ExpenseHeading>
    <oef:ExpenseNarrativeTextBlock
      contextRef="Pid_S000007007_contentCd_ASTP-PRO"
      id="ixv-2968">


     The following table describes the fees and expenses that may be incurred when you buy, hold, and sell shares of the fund. You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and examples below.


      You may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $



       250,000



      in the fund or certain other Fidelity

      &#xae;

      funds. More information about these and other discounts is available from your investment professional and in the "Fund Distribution" section beginning on page


      35

      of the prospectus



     &#160;
     and in

     the sales charge

     waiver appendix to

     the prospectus.

   </oef:ExpenseNarrativeTextBlock>
    <oef:ExpenseBreakpointDiscounts
      contextRef="Pid_S000007007_contentCd_ASTP-PRO"
      id="ixv-2974">

      You may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $



       250,000



      in the fund or certain other Fidelity

      &#xae;

      funds. More information about these and other discounts is available from your investment professional and in the "Fund Distribution" section beginning on page


      35

      of the prospectus

     </oef:ExpenseBreakpointDiscounts>
    <oef:ExpenseBreakpointMinimumInvestmentRequiredAmount
      contextRef="Pid_S000007007_contentCd_ASTP-PRO"
      decimals="0"
      id="ixv-101266"
      unitRef="usd">250000</oef:ExpenseBreakpointMinimumInvestmentRequiredAmount>
    <oef:ShareholderFeesCaption
      contextRef="Pid_S000007007_contentCd_ASTP-PRO"
      id="ixv-3000">


     Shareholder fees


   </oef:ShareholderFeesCaption>
    <oef:MaximumCumulativeSalesChargeOverOfferingPrice
      contextRef="Pid_S000007007_Cid_C000171437"
      decimals="4"
      id="ixv-101267"
      unitRef="pure">0.0150</oef:MaximumCumulativeSalesChargeOverOfferingPrice>
    <oef:MaximumCumulativeSalesChargeOverOfferingPrice
      contextRef="Pid_S000007007_Cid_C000171438"
      decimals="4"
      id="ixv-101268"
      unitRef="pure">0.0150</oef:MaximumCumulativeSalesChargeOverOfferingPrice>
    <oef:MaximumCumulativeSalesChargeOverOfferingPrice
      contextRef="Pid_S000007007_Cid_C000171439"
      decimals="4"
      id="ixv-101269"
      unitRef="pure">0</oef:MaximumCumulativeSalesChargeOverOfferingPrice>
    <oef:MaximumCumulativeSalesChargeOverOfferingPrice
      contextRef="Pid_S000007007_Cid_C000171440"
      decimals="4"
      id="ixv-101270"
      unitRef="pure">0</oef:MaximumCumulativeSalesChargeOverOfferingPrice>
    <oef:MaximumCumulativeSalesChargeOverOfferingPrice
      contextRef="Pid_S000007007_Cid_C000205020"
      decimals="4"
      id="ixv-101271"
      unitRef="pure">0</oef:MaximumCumulativeSalesChargeOverOfferingPrice>
    <oef:MaximumDeferredSalesChargeOverOther
      contextRef="Pid_S000007007_Cid_C000171437"
      decimals="4"
      id="footnoteASTP-PROS000007007SHF_AC000171437"
      unitRef="pure">0</oef:MaximumDeferredSalesChargeOverOther>
    <oef:MaximumDeferredSalesChargeOverOther
      contextRef="Pid_S000007007_Cid_C000171438"
      decimals="4"
      id="footnoteASTP-PROS000007007SHF_BC000171438"
      unitRef="pure">0</oef:MaximumDeferredSalesChargeOverOther>
    <oef:MaximumDeferredSalesChargeOverOther
      contextRef="Pid_S000007007_Cid_C000171439"
      decimals="4"
      id="footnoteASTP-PROS000007007SHF_CC000171439"
      unitRef="pure">0.0100</oef:MaximumDeferredSalesChargeOverOther>
    <oef:MaximumDeferredSalesChargeOverOther
      contextRef="Pid_S000007007_Cid_C000171440"
      decimals="4"
      id="ixv-101275"
      unitRef="pure">0</oef:MaximumDeferredSalesChargeOverOther>
    <oef:MaximumDeferredSalesChargeOverOther
      contextRef="Pid_S000007007_Cid_C000205020"
      decimals="4"
      id="ixv-101276"
      unitRef="pure">0</oef:MaximumDeferredSalesChargeOverOther>
    <oef:ExpensesDeferredChargesTextBlock contextRef="Pid_S000007007_Cid_C000171437" id="ixv-3106">

      Purchases of $250,000 or more will not be subject to a front-end sales charge, but may be subject to a 0.50% contingent deferred sales charge (CDSC) if the intermediary firm has elected an upfront finder's fee at the time the shares are purchased, or a 0.75% CDSC if the shares purchased are recordkept in a Fidelity Advisor

      &#xae;
      401(k) Retirement Plan.

     </oef:ExpensesDeferredChargesTextBlock>
    <oef:ExpensesDeferredChargesTextBlock contextRef="Pid_S000007007_Cid_C000171438" id="ixv-3119">

      Purchases of $250,000 or more will not be subject to a front-end sales charge but may be subject to a 0.25% CDSC if a finder's fee is paid at the time the shares are purchased.

     </oef:ExpensesDeferredChargesTextBlock>
    <oef:ExpensesDeferredChargesTextBlock contextRef="Pid_S000007007_Cid_C000171439" id="ixv-3129">

      On Class C shares redeemed less than one year after purchase.

     </oef:ExpensesDeferredChargesTextBlock>
    <oef:OperatingExpensesCaption
      contextRef="Pid_S000007007_contentCd_ASTP-PRO"
      id="ixv-3134">


     Annual Operating Expenses


   </oef:OperatingExpensesCaption>
    <oef:ManagementFeesOverAssets
      contextRef="Pid_S000007007_Cid_C000171437"
      decimals="6"
      id="ixv-101277"
      unitRef="pure">0.0020</oef:ManagementFeesOverAssets>
    <oef:ManagementFeesOverAssets
      contextRef="Pid_S000007007_Cid_C000171438"
      decimals="6"
      id="ixv-101278"
      unitRef="pure">0.0020</oef:ManagementFeesOverAssets>
    <oef:ManagementFeesOverAssets
      contextRef="Pid_S000007007_Cid_C000171439"
      decimals="6"
      id="ixv-101279"
      unitRef="pure">0.0020</oef:ManagementFeesOverAssets>
    <oef:ManagementFeesOverAssets
      contextRef="Pid_S000007007_Cid_C000171440"
      decimals="6"
      id="ixv-101280"
      unitRef="pure">0.0020</oef:ManagementFeesOverAssets>
    <oef:ManagementFeesOverAssets
      contextRef="Pid_S000007007_Cid_C000205020"
      decimals="6"
      id="ixv-101281"
      unitRef="pure">0.0020</oef:ManagementFeesOverAssets>
    <oef:DistributionAndService12b1FeesOverAssets
      contextRef="Pid_S000007007_Cid_C000171437"
      decimals="6"
      id="ixv-101282"
      unitRef="pure">0.0015</oef:DistributionAndService12b1FeesOverAssets>
    <oef:DistributionAndService12b1FeesOverAssets
      contextRef="Pid_S000007007_Cid_C000171438"
      decimals="6"
      id="ixv-101283"
      unitRef="pure">0.0015</oef:DistributionAndService12b1FeesOverAssets>
    <oef:DistributionAndService12b1FeesOverAssets
      contextRef="Pid_S000007007_Cid_C000171439"
      decimals="6"
      id="ixv-101284"
      unitRef="pure">0.0100</oef:DistributionAndService12b1FeesOverAssets>
    <oef:DistributionAndService12b1FeesOverAssets
      contextRef="Pid_S000007007_Cid_C000171440"
      decimals="6"
      id="ixv-101285"
      unitRef="pure">0</oef:DistributionAndService12b1FeesOverAssets>
    <oef:DistributionAndService12b1FeesOverAssets
      contextRef="Pid_S000007007_Cid_C000205020"
      decimals="6"
      id="ixv-101286"
      unitRef="pure">0</oef:DistributionAndService12b1FeesOverAssets>
    <oef:OtherExpensesOverAssets
      contextRef="Pid_S000007007_Cid_C000171437"
      decimals="6"
      id="ixv-101287"
      unitRef="pure">0.0015</oef:OtherExpensesOverAssets>
    <oef:OtherExpensesOverAssets
      contextRef="Pid_S000007007_Cid_C000171438"
      decimals="6"
      id="ixv-101288"
      unitRef="pure">0.0016</oef:OtherExpensesOverAssets>
    <oef:OtherExpensesOverAssets
      contextRef="Pid_S000007007_Cid_C000171439"
      decimals="6"
      id="ixv-101289"
      unitRef="pure">0.0016</oef:OtherExpensesOverAssets>
    <oef:OtherExpensesOverAssets
      contextRef="Pid_S000007007_Cid_C000171440"
      decimals="6"
      id="ixv-101290"
      unitRef="pure">0.0015</oef:OtherExpensesOverAssets>
    <oef:OtherExpensesOverAssets
      contextRef="Pid_S000007007_Cid_C000205020"
      decimals="6"
      id="ixv-101291"
      unitRef="pure">0.0005</oef:OtherExpensesOverAssets>
    <oef:ExpensesOverAssets
      contextRef="Pid_S000007007_Cid_C000171437"
      decimals="6"
      id="ixv-101292"
      unitRef="pure">0.0050</oef:ExpensesOverAssets>
    <oef:ExpensesOverAssets
      contextRef="Pid_S000007007_Cid_C000171438"
      decimals="6"
      id="ixv-101293"
      unitRef="pure">0.0051</oef:ExpensesOverAssets>
    <oef:ExpensesOverAssets
      contextRef="Pid_S000007007_Cid_C000171439"
      decimals="6"
      id="ixv-101294"
      unitRef="pure">0.0136</oef:ExpensesOverAssets>
    <oef:ExpensesOverAssets
      contextRef="Pid_S000007007_Cid_C000171440"
      decimals="6"
      id="ixv-101295"
      unitRef="pure">0.0035</oef:ExpensesOverAssets>
    <oef:ExpensesOverAssets
      contextRef="Pid_S000007007_Cid_C000205020"
      decimals="6"
      id="ixv-101296"
      unitRef="pure">0.0025</oef:ExpensesOverAssets>
    <oef:FeeWaiverOrReimbursementOverAssets
      contextRef="Pid_S000007007_Cid_C000171437"
      decimals="6"
      id="ixv-101297"
      unitRef="pure">-0.0000</oef:FeeWaiverOrReimbursementOverAssets>
    <oef:FeeWaiverOrReimbursementOverAssets
      contextRef="Pid_S000007007_Cid_C000171438"
      decimals="6"
      id="ixv-101298"
      unitRef="pure">-0.0000</oef:FeeWaiverOrReimbursementOverAssets>
    <oef:FeeWaiverOrReimbursementOverAssets
      contextRef="Pid_S000007007_Cid_C000171439"
      decimals="6"
      id="ixv-101299"
      unitRef="pure">-0.0000</oef:FeeWaiverOrReimbursementOverAssets>
    <oef:FeeWaiverOrReimbursementOverAssets
      contextRef="Pid_S000007007_Cid_C000171440"
      decimals="6"
      id="footnoteS000007007ASTP-PROAOE_AC000171440_FW"
      unitRef="pure">-0.0005</oef:FeeWaiverOrReimbursementOverAssets>
    <oef:FeeWaiverOrReimbursementOverAssets
      contextRef="Pid_S000007007_Cid_C000205020"
      decimals="6"
      id="ixv-101301"
      unitRef="pure">-0.0000</oef:FeeWaiverOrReimbursementOverAssets>
    <oef:NetExpensesOverAssets
      contextRef="Pid_S000007007_Cid_C000171437"
      decimals="6"
      id="ixv-101302"
      unitRef="pure">0.0050</oef:NetExpensesOverAssets>
    <oef:NetExpensesOverAssets
      contextRef="Pid_S000007007_Cid_C000171438"
      decimals="6"
      id="ixv-101303"
      unitRef="pure">0.0051</oef:NetExpensesOverAssets>
    <oef:NetExpensesOverAssets
      contextRef="Pid_S000007007_Cid_C000171439"
      decimals="6"
      id="ixv-101304"
      unitRef="pure">0.0136</oef:NetExpensesOverAssets>
    <oef:NetExpensesOverAssets
      contextRef="Pid_S000007007_Cid_C000171440"
      decimals="6"
      id="ixv-101305"
      unitRef="pure">0.0030</oef:NetExpensesOverAssets>
    <oef:NetExpensesOverAssets
      contextRef="Pid_S000007007_Cid_C000205020"
      decimals="6"
      id="ixv-101306"
      unitRef="pure">0.0025</oef:NetExpensesOverAssets>
    <oef:FeeWaiverOrReimbursementOverAssetsDateOfTermination
      contextRef="Pid_S000007007_contentCd_ASTP-PRO"
      id="ixv-3368">2026-12-31</oef:FeeWaiverOrReimbursementOverAssetsDateOfTermination>
    <oef:ExpenseExampleNarrativeTextBlock
      contextRef="Pid_S000007007_contentCd_ASTP-PRO"
      id="ixv-3379">


     This
     example

     helps compare the cost of investing in the fund with the cost of investing in other funds.

     Let's say, hypothetically, that the annual return for shares of the fund is 5% and that the fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated and if you hold your shares:

   </oef:ExpenseExampleNarrativeTextBlock>
    <oef:ExpenseExampleYear01
      contextRef="Pid_S000007007_Cid_C000171437"
      decimals="0"
      id="ixv-101307"
      unitRef="usd">200</oef:ExpenseExampleYear01>
    <oef:ExpenseExampleNoRedemptionYear01
      contextRef="Pid_S000007007_Cid_C000171437"
      decimals="0"
      id="ixv-101308"
      unitRef="usd">200</oef:ExpenseExampleNoRedemptionYear01>
    <oef:ExpenseExampleYear01
      contextRef="Pid_S000007007_Cid_C000171438"
      decimals="0"
      id="ixv-101309"
      unitRef="usd">201</oef:ExpenseExampleYear01>
    <oef:ExpenseExampleNoRedemptionYear01
      contextRef="Pid_S000007007_Cid_C000171438"
      decimals="0"
      id="ixv-101310"
      unitRef="usd">201</oef:ExpenseExampleNoRedemptionYear01>
    <oef:ExpenseExampleYear01
      contextRef="Pid_S000007007_Cid_C000171439"
      decimals="0"
      id="ixv-101311"
      unitRef="usd">238</oef:ExpenseExampleYear01>
    <oef:ExpenseExampleNoRedemptionYear01
      contextRef="Pid_S000007007_Cid_C000171439"
      decimals="0"
      id="ixv-101312"
      unitRef="usd">138</oef:ExpenseExampleNoRedemptionYear01>
    <oef:ExpenseExampleYear01
      contextRef="Pid_S000007007_Cid_C000171440"
      decimals="0"
      id="ixv-101313"
      unitRef="usd">31</oef:ExpenseExampleYear01>
    <oef:ExpenseExampleNoRedemptionYear01
      contextRef="Pid_S000007007_Cid_C000171440"
      decimals="0"
      id="ixv-101314"
      unitRef="usd">31</oef:ExpenseExampleNoRedemptionYear01>
    <oef:ExpenseExampleYear01
      contextRef="Pid_S000007007_Cid_C000205020"
      decimals="0"
      id="ixv-101315"
      unitRef="usd">26</oef:ExpenseExampleYear01>
    <oef:ExpenseExampleNoRedemptionYear01
      contextRef="Pid_S000007007_Cid_C000205020"
      decimals="0"
      id="ixv-101316"
      unitRef="usd">26</oef:ExpenseExampleNoRedemptionYear01>
    <oef:ExpenseExampleYear03
      contextRef="Pid_S000007007_Cid_C000171437"
      decimals="0"
      id="ixv-101317"
      unitRef="usd">308</oef:ExpenseExampleYear03>
    <oef:ExpenseExampleNoRedemptionYear03
      contextRef="Pid_S000007007_Cid_C000171437"
      decimals="0"
      id="ixv-101318"
      unitRef="usd">308</oef:ExpenseExampleNoRedemptionYear03>
    <oef:ExpenseExampleYear03
      contextRef="Pid_S000007007_Cid_C000171438"
      decimals="0"
      id="ixv-101319"
      unitRef="usd">311</oef:ExpenseExampleYear03>
    <oef:ExpenseExampleNoRedemptionYear03
      contextRef="Pid_S000007007_Cid_C000171438"
      decimals="0"
      id="ixv-101320"
      unitRef="usd">311</oef:ExpenseExampleNoRedemptionYear03>
    <oef:ExpenseExampleYear03
      contextRef="Pid_S000007007_Cid_C000171439"
      decimals="0"
      id="ixv-101321"
      unitRef="usd">431</oef:ExpenseExampleYear03>
    <oef:ExpenseExampleNoRedemptionYear03
      contextRef="Pid_S000007007_Cid_C000171439"
      decimals="0"
      id="ixv-101322"
      unitRef="usd">431</oef:ExpenseExampleNoRedemptionYear03>
    <oef:ExpenseExampleYear03
      contextRef="Pid_S000007007_Cid_C000171440"
      decimals="0"
      id="ixv-101323"
      unitRef="usd">106</oef:ExpenseExampleYear03>
    <oef:ExpenseExampleNoRedemptionYear03
      contextRef="Pid_S000007007_Cid_C000171440"
      decimals="0"
      id="ixv-101324"
      unitRef="usd">106</oef:ExpenseExampleNoRedemptionYear03>
    <oef:ExpenseExampleYear03
      contextRef="Pid_S000007007_Cid_C000205020"
      decimals="0"
      id="ixv-101325"
      unitRef="usd">80</oef:ExpenseExampleYear03>
    <oef:ExpenseExampleNoRedemptionYear03
      contextRef="Pid_S000007007_Cid_C000205020"
      decimals="0"
      id="ixv-101326"
      unitRef="usd">80</oef:ExpenseExampleNoRedemptionYear03>
    <oef:ExpenseExampleYear05
      contextRef="Pid_S000007007_Cid_C000171437"
      decimals="0"
      id="ixv-101327"
      unitRef="usd">425</oef:ExpenseExampleYear05>
    <oef:ExpenseExampleNoRedemptionYear05
      contextRef="Pid_S000007007_Cid_C000171437"
      decimals="0"
      id="ixv-101328"
      unitRef="usd">425</oef:ExpenseExampleNoRedemptionYear05>
    <oef:ExpenseExampleYear05
      contextRef="Pid_S000007007_Cid_C000171438"
      decimals="0"
      id="ixv-101329"
      unitRef="usd">431</oef:ExpenseExampleYear05>
    <oef:ExpenseExampleNoRedemptionYear05
      contextRef="Pid_S000007007_Cid_C000171438"
      decimals="0"
      id="ixv-101330"
      unitRef="usd">431</oef:ExpenseExampleNoRedemptionYear05>
    <oef:ExpenseExampleYear05
      contextRef="Pid_S000007007_Cid_C000171439"
      decimals="0"
      id="ixv-101331"
      unitRef="usd">745</oef:ExpenseExampleYear05>
    <oef:ExpenseExampleNoRedemptionYear05
      contextRef="Pid_S000007007_Cid_C000171439"
      decimals="0"
      id="ixv-101332"
      unitRef="usd">745</oef:ExpenseExampleNoRedemptionYear05>
    <oef:ExpenseExampleYear05
      contextRef="Pid_S000007007_Cid_C000171440"
      decimals="0"
      id="ixv-101333"
      unitRef="usd">190</oef:ExpenseExampleYear05>
    <oef:ExpenseExampleNoRedemptionYear05
      contextRef="Pid_S000007007_Cid_C000171440"
      decimals="0"
      id="ixv-101334"
      unitRef="usd">190</oef:ExpenseExampleNoRedemptionYear05>
    <oef:ExpenseExampleYear05
      contextRef="Pid_S000007007_Cid_C000205020"
      decimals="0"
      id="ixv-101335"
      unitRef="usd">141</oef:ExpenseExampleYear05>
    <oef:ExpenseExampleNoRedemptionYear05
      contextRef="Pid_S000007007_Cid_C000205020"
      decimals="0"
      id="ixv-101336"
      unitRef="usd">141</oef:ExpenseExampleNoRedemptionYear05>
    <oef:ExpenseExampleYear10
      contextRef="Pid_S000007007_Cid_C000171437"
      decimals="0"
      id="ixv-101337"
      unitRef="usd">769</oef:ExpenseExampleYear10>
    <oef:ExpenseExampleNoRedemptionYear10
      contextRef="Pid_S000007007_Cid_C000171437"
      decimals="0"
      id="ixv-101338"
      unitRef="usd">769</oef:ExpenseExampleNoRedemptionYear10>
    <oef:ExpenseExampleYear10
      contextRef="Pid_S000007007_Cid_C000171438"
      decimals="0"
      id="ixv-101339"
      unitRef="usd">781</oef:ExpenseExampleYear10>
    <oef:ExpenseExampleNoRedemptionYear10
      contextRef="Pid_S000007007_Cid_C000171438"
      decimals="0"
      id="ixv-101340"
      unitRef="usd">781</oef:ExpenseExampleNoRedemptionYear10>
    <oef:ExpenseExampleYear10
      contextRef="Pid_S000007007_Cid_C000171439"
      decimals="0"
      id="ixv-101341"
      unitRef="usd">1399</oef:ExpenseExampleYear10>
    <oef:ExpenseExampleNoRedemptionYear10
      contextRef="Pid_S000007007_Cid_C000171439"
      decimals="0"
      id="ixv-101342"
      unitRef="usd">1399</oef:ExpenseExampleNoRedemptionYear10>
    <oef:ExpenseExampleYear10
      contextRef="Pid_S000007007_Cid_C000171440"
      decimals="0"
      id="ixv-101343"
      unitRef="usd">437</oef:ExpenseExampleYear10>
    <oef:ExpenseExampleNoRedemptionYear10
      contextRef="Pid_S000007007_Cid_C000171440"
      decimals="0"
      id="ixv-101344"
      unitRef="usd">437</oef:ExpenseExampleNoRedemptionYear10>
    <oef:ExpenseExampleYear10
      contextRef="Pid_S000007007_Cid_C000205020"
      decimals="0"
      id="ixv-101345"
      unitRef="usd">318</oef:ExpenseExampleYear10>
    <oef:ExpenseExampleNoRedemptionYear10
      contextRef="Pid_S000007007_Cid_C000205020"
      decimals="0"
      id="ixv-101346"
      unitRef="usd">318</oef:ExpenseExampleNoRedemptionYear10>
    <oef:PortfolioTurnoverHeading
      contextRef="Pid_S000007007_contentCd_ASTP-PRO"
      id="ixv-3687">


     Portfolio Turnover


   </oef:PortfolioTurnoverHeading>
    <oef:PortfolioTurnoverTextBlock
      contextRef="Pid_S000007007_contentCd_ASTP-PRO"
      id="ixv-3692">


     The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was



       59


     % of the average value of its portfolio.


   </oef:PortfolioTurnoverTextBlock>
    <oef:PortfolioTurnoverRate
      contextRef="Pid_S000007007_contentCd_ASTP-PRO"
      decimals="4"
      id="ixv-101347"
      unitRef="pure">0.59</oef:PortfolioTurnoverRate>
    <oef:StrategyHeading
      contextRef="Pid_S000007007_contentCd_ASTP-PRO"
      id="ixv-3701">


     Principal Investment Strategies


   </oef:StrategyHeading>
    <oef:StrategyNarrativeTextBlock
      contextRef="Pid_S000007007_contentCd_ASTP-PRO"
      id="ixv-3706">




        Normally investing at least 80% of assets in investment-grade debt securities (those of medium and high quality) of all types and repurchase agreements for those securities.

     Debt securities are used by issuers to borrow money. The issuer usually pays a fixed, variable, or floating rate of interest, and must repay the amount borrowed, usually at the maturity of the security. Debt securities include corporate bonds, government securities (including Treasury securities), repurchase agreements, money market securities, mortgage and other asset-backed securities, loans and loan participations, and other securities, such as hybrids and synthetic securities, believed to have debt-like characteristics (e.g., securities classified as Tier 2 Regulatory capital, securities that rank above share capital in an insolvency waterfall, securities with maturity dates and non-cancellable interest payment structures).&#160;
     Investment grade securities in which the fund invests include securities or issuers rated at least BBB- or its equivalent by at least one nationally recognized statistical ratings organization (NRSRO), or, if unrated, determined by the Adviser to be of comparable quality.
     A repurchase agreement is an agreement to buy a security at one price and a simultaneous agreement to sell it back at an agreed-upon price.
     Effective December 11, 2025, derivative instruments that provide investment exposure to the investments above or exposure to one or more market risk factors associated with such investments are included in the fund's 80% policy, consistent with the fund's investment policies and limitations with respect to investments in derivatives.

      &#160;
      Managing the fund to have similar overall interest rate risk to the Bloomberg U.S. 1-3 Year Government/Credit Bond Index.
      Normally maintaining a dollar-weighted average maturity of three years or less.
      Allocating assets across different market sectors and maturities.
      Investing in domestic and foreign issuers.
      Analyzing the credit quality of the issuer, security-specific features, current and potential future valuation, and trading opportunities to select investments.
      Engaging in transactions that have a leveraging effect on the fund, including investments in derivatives - such as swaps (interest rate, total return, and credit default), options, and futures contracts - and forward-settling securities, to adjust the fund's risk exposure.
      Investing in Fidelity's Central funds (specialized investment vehicles used by Fidelity&#xae; funds to invest in particular security types or investment disciplines) consistent with the asset classes discussed above.


   </oef:StrategyNarrativeTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000007007_contentCd_ASTP-PRO_RiskMember_InterestRateChangesMember"
      id="ixv-3743">



      Interest Rate Changes.

     Interest rate increases can cause the price of a debt security to decrease.

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000007007_contentCd_ASTP-PRO_RiskMember_ForeignExposureMember"
      id="ixv-3752">



      Foreign Exposure.

     Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market.

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000007007_contentCd_ASTP-PRO_RiskMember_PrepaymentMember"
      id="ixv-3761">



      Prepayment.

     The ability of an issuer of a debt security to repay principal prior to a security's maturity can cause greater price volatility if interest rates change.

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000007007_contentCd_ASTP-PRO_RiskMember_IssuerSpecificChangesMember"
      id="ixv-3770">



      Issuer-Specific Changes.

     The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole.
     A decline in the credit quality of an issuer or a provider of credit support (such as guarantees) or a maturity-shortening structure (such as demand and put features) for a security can cause the price of a security to decrease.

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000007007_contentCd_ASTP-PRO_RiskMember_LeverageRiskMember"
      id="ixv-3785">



      Leverage Risk.

     Leverage can increase market exposure, magnify investment risks, and cause losses to be realized more quickly.



   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000007007_contentCd_ASTP-PRO_RiskMember_RiskNotInsuredDepositoryInstitutionMember"
      id="ixv-3795">


     An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency

     .


   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000007007_contentCd_ASTP-PRO_RiskMember_RiskLoseMoneyMember"
      id="ixv-3803">


     &#160;

     You could lose money by investing in the fund.


   </oef:RiskTextBlock>
    <oef:BarChartAndPerformanceTableHeading
      contextRef="Pid_S000007007_contentCd_ASTP-PRO"
      id="ixv-3812">


     Performance


   </oef:BarChartAndPerformanceTableHeading>
    <oef:PerformanceNarrativeTextBlock
      contextRef="Pid_S000007007_contentCd_ASTP-PRO"
      id="ixv-3817">



       The following information is intended to help you understand the risks of investing in the fund.


      The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time.



     The additional index has characteristics relevant to the fund's investment strategies. Index descriptions appear

     in the "Additional Index Information" section of the prospectus.



      Past performance (before and after taxes) is not an indication of future performance.


     Visit



      institutional.fidelity.com


     for more recent performance information.

   </oef:PerformanceNarrativeTextBlock>
    <oef:PerformanceInformationIllustratesVariabilityOfReturns
      contextRef="Pid_S000007007_contentCd_ASTP-PRO"
      id="ixv-3823">

      The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time.

     </oef:PerformanceInformationIllustratesVariabilityOfReturns>
    <oef:PerformancePastDoesNotIndicateFuture
      contextRef="Pid_S000007007_contentCd_ASTP-PRO"
      id="ixv-3832">

      Past performance (before and after taxes) is not an indication of future performance.

     </oef:PerformancePastDoesNotIndicateFuture>
    <oef:PerformanceAvailabilityWebSiteAddress
      contextRef="Pid_S000007007_contentCd_ASTP-PRO"
      id="ixv-3838">

      institutional.fidelity.com
     </oef:PerformanceAvailabilityWebSiteAddress>
    <oef:BarChartHeading
      contextRef="Pid_S000007007_contentCd_ASTP-PRO"
      id="ixv-3843">


     Year-by-Year Returns

   </oef:BarChartHeading>
    <oef:BarChartNarrativeTextBlock
      contextRef="Pid_S000007007_contentCd_ASTP-PRO"
      id="ixv-3847">




      The returns in the bar chart do not reflect any applicable sales charges; if sales charges were reflected, returns would be lower than those shown.




   </oef:BarChartNarrativeTextBlock>
    <oef:BarChartDoesNotReflectSalesLoads
      contextRef="Pid_S000007007_contentCd_ASTP-PRO"
      id="ixv-3850">

      The returns in the bar chart do not reflect any applicable sales charges; if sales charges were reflected, returns would be lower than those shown.

     </oef:BarChartDoesNotReflectSalesLoads>
    <oef:AnnlRtrPct
      contextRef="Pid_S000007007_Cid_C000171437_2017"
      decimals="INF"
      id="ixv-101348"
      unitRef="pure">0.0095</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000007007_Cid_C000171437_2018"
      decimals="INF"
      id="ixv-101349"
      unitRef="pure">0.0099</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000007007_Cid_C000171437_2019"
      decimals="INF"
      id="ixv-101350"
      unitRef="pure">0.0399</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000007007_Cid_C000171437_2020"
      decimals="INF"
      id="ixv-101351"
      unitRef="pure">0.0362</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000007007_Cid_C000171437_2021"
      decimals="INF"
      id="ixv-101352"
      unitRef="pure">-0.0093</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000007007_Cid_C000171437_2022"
      decimals="INF"
      id="ixv-101353"
      unitRef="pure">-0.0380</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000007007_Cid_C000171437_2023"
      decimals="INF"
      id="ixv-101354"
      unitRef="pure">0.0500</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000007007_Cid_C000171437_2024"
      decimals="INF"
      id="ixv-101355"
      unitRef="pure">0.0463</oef:AnnlRtrPct>
    <oef:HighestQuarterlyReturnLabel
      contextRef="Pid_S000007007_contentCd_ASTP-PRO"
      id="ixv-3956">
          &#160;&#160;&#160;Highest Quarter Return
        </oef:HighestQuarterlyReturnLabel>
    <oef:BarChartHighestQuarterlyReturn
      contextRef="Pid_S000007007_contentCd_ASTP-PRO"
      decimals="4"
      id="ixv-101356"
      unitRef="pure">0.0293</oef:BarChartHighestQuarterlyReturn>
    <oef:BarChartHighestQuarterlyReturnDate
      contextRef="Pid_S000007007_contentCd_ASTP-PRO"
      id="ixv-3966">2020-06-30</oef:BarChartHighestQuarterlyReturnDate>
    <oef:LowestQuarterlyReturnLabel
      contextRef="Pid_S000007007_contentCd_ASTP-PRO"
      id="ixv-3971">
          &#160;&#160;&#160;Lowest Quarter Return
        </oef:LowestQuarterlyReturnLabel>
    <oef:BarChartLowestQuarterlyReturn
      contextRef="Pid_S000007007_contentCd_ASTP-PRO"
      decimals="4"
      id="ixv-101357"
      unitRef="pure">-0.0266</oef:BarChartLowestQuarterlyReturn>
    <oef:BarChartLowestQuarterlyReturnDate
      contextRef="Pid_S000007007_contentCd_ASTP-PRO"
      id="ixv-3982">2022-03-31</oef:BarChartLowestQuarterlyReturnDate>
    <oef:YearToDateReturnLabel
      contextRef="Pid_S000007007_contentCd_ASTP-PRO"
      id="ixv-3987">
          &#160;&#160;&#160;Year-to-Date Return
        </oef:YearToDateReturnLabel>
    <oef:BarChartYearToDateReturn
      contextRef="Pid_S000007007_contentCd_ASTP-PRO"
      decimals="4"
      id="ixv-101358"
      unitRef="pure">0.0414</oef:BarChartYearToDateReturn>
    <oef:BarChartYearToDateReturnDate
      contextRef="Pid_S000007007_contentCd_ASTP-PRO"
      id="ixv-3997">2025-09-30</oef:BarChartYearToDateReturnDate>
    <oef:PerformanceTableHeading
      contextRef="Pid_S000007007_contentCd_ASTP-PRO"
      id="ixv-4002">


     Average Annual Returns


   </oef:PerformanceTableHeading>
    <oef:PerformanceTableNarrativeTextBlock
      contextRef="Pid_S000007007_contentCd_ASTP-PRO"
      id="ixv-4008">




      Unlike the returns in the bar chart, the returns in the table reflect the maximum applicable sales charges.





      After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes.





      After-tax returns for Class A are shown in the table below and after-tax returns for other classes will vary.



     Actual after-tax returns may differ depending on your individual circumstances.


      The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan).




      Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.




   </oef:PerformanceTableNarrativeTextBlock>
    <oef:PerformanceTableDoesReflectSalesLoads
      contextRef="Pid_S000007007_contentCd_ASTP-PRO"
      id="ixv-4011">

      Unlike the returns in the bar chart, the returns in the table reflect the maximum applicable sales charges.

     </oef:PerformanceTableDoesReflectSalesLoads>
    <oef:PerformanceTableUsesHighestFederalRate
      contextRef="Pid_S000007007_contentCd_ASTP-PRO"
      id="ixv-4016">

      After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes.

     </oef:PerformanceTableUsesHighestFederalRate>
    <oef:PerformanceTableOneClassOfAfterTaxShown
      contextRef="Pid_S000007007_contentCd_ASTP-PRO"
      id="ixv-4021">

      After-tax returns for Class A are shown in the table below and after-tax returns for other classes will vary.

     </oef:PerformanceTableOneClassOfAfterTaxShown>
    <oef:PerformanceTableNotRelevantToTaxDeferred
      contextRef="Pid_S000007007_contentCd_ASTP-PRO"
      id="ixv-4027">

      The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan).
     </oef:PerformanceTableNotRelevantToTaxDeferred>
    <oef:PerformanceTableExplanationAfterTaxHigher
      contextRef="Pid_S000007007_contentCd_ASTP-PRO"
      id="ixv-4031">

      Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

     </oef:PerformanceTableExplanationAfterTaxHigher>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000007007_Cid_C000171437_ReturnBeforeTaxes_01"
      id="ixv-4062">
         Return Before Taxes
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007007_Cid_C000171437_ReturnBeforeTaxes_01"
      decimals="4"
      id="ixv-101359"
      unitRef="pure">0.0306</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007007_Cid_C000171437_ReturnBeforeTaxes_05"
      decimals="4"
      id="ixv-101360"
      unitRef="pure">0.0134</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007007_Cid_C000171437_ReturnBeforeTaxes_AverageAnnualReturnSinceInception"
      decimals="4"
      id="footnoteASTP-PROS000007007AAR_A_RBT_loc"
      unitRef="pure">0.0145</oef:AvgAnnlRtrPct>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000007007_Cid_C000171437_AfterTaxesOnDistributions_01"
      id="ixv-4080">
         Return After Taxes on Distributions
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007007_Cid_C000171437_AfterTaxesOnDistributions_01"
      decimals="4"
      id="ixv-101362"
      unitRef="pure">0.0151</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007007_Cid_C000171437_AfterTaxesOnDistributions_05"
      decimals="4"
      id="ixv-101363"
      unitRef="pure">0.0045</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007007_Cid_C000171437_AfterTaxesOnDistributions_AverageAnnualReturnSinceInception"
      decimals="4"
      id="footnoteASTP-PROS000007007AAR_A_ATD_loc"
      unitRef="pure">0.0068</oef:AvgAnnlRtrPct>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000007007_Cid_C000171437_AfterTaxesOnDistributionsAndSales_01"
      id="ixv-4096">
          Return After Taxes on Distributions and Sale of Fund Shares
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007007_Cid_C000171437_AfterTaxesOnDistributionsAndSales_01"
      decimals="4"
      id="ixv-101365"
      unitRef="pure">0.0183</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007007_Cid_C000171437_AfterTaxesOnDistributionsAndSales_05"
      decimals="4"
      id="ixv-101366"
      unitRef="pure">0.0065</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007007_Cid_C000171437_AfterTaxesOnDistributionsAndSales_AverageAnnualReturnSinceInception"
      decimals="4"
      id="footnoteASTP-PROS000007007AAR_A_ATDS_loc"
      unitRef="pure">0.0078</oef:AvgAnnlRtrPct>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000007007_Cid_C000171438_ReturnBeforeTaxes_01"
      id="ixv-4112">
         Return Before Taxes
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007007_Cid_C000171438_ReturnBeforeTaxes_01"
      decimals="4"
      id="ixv-101368"
      unitRef="pure">0.0305</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007007_Cid_C000171438_ReturnBeforeTaxes_05"
      decimals="4"
      id="ixv-101369"
      unitRef="pure">0.0133</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007007_Cid_C000171438_ReturnBeforeTaxes_AverageAnnualReturnSinceInception"
      decimals="4"
      id="footnoteASTP-PROS000007007AAR_B_RBT_loc"
      unitRef="pure">0.0144</oef:AvgAnnlRtrPct>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000007007_Cid_C000171439_ReturnBeforeTaxes_01"
      id="ixv-4128">
         Return Before Taxes
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007007_Cid_C000171439_ReturnBeforeTaxes_01"
      decimals="4"
      id="ixv-101371"
      unitRef="pure">0.0274</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007007_Cid_C000171439_ReturnBeforeTaxes_05"
      decimals="4"
      id="ixv-101372"
      unitRef="pure">0.0077</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007007_Cid_C000171439_ReturnBeforeTaxes_AverageAnnualReturnSinceInception"
      decimals="4"
      id="footnoteASTP-PROS000007007AAR_C_RBT_loc"
      unitRef="pure">0.0081</oef:AvgAnnlRtrPct>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000007007_Cid_C000171440_ReturnBeforeTaxes_01"
      id="ixv-4144">
         Return Before Taxes
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007007_Cid_C000171440_ReturnBeforeTaxes_01"
      decimals="4"
      id="ixv-101374"
      unitRef="pure">0.0483</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007007_Cid_C000171440_ReturnBeforeTaxes_05"
      decimals="4"
      id="ixv-101375"
      unitRef="pure">0.0181</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007007_Cid_C000171440_ReturnBeforeTaxes_AverageAnnualReturnSinceInception"
      decimals="4"
      id="footnoteASTP-PROS000007007AAR_D_RBT_loc"
      unitRef="pure">0.0179</oef:AvgAnnlRtrPct>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000007007_Cid_C000205020_ReturnBeforeTaxes_01"
      id="ixv-4160">
         Return Before Taxes
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007007_Cid_C000205020_ReturnBeforeTaxes_01"
      decimals="4"
      id="ixv-101377"
      unitRef="pure">0.0476</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007007_Cid_C000205020_ReturnBeforeTaxes_05"
      decimals="4"
      id="ixv-101378"
      unitRef="pure">0.0192</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007007_Cid_C000205020_ReturnBeforeTaxes_AverageAnnualReturnSinceInception"
      decimals="4"
      id="footnoteASTP-PROS000007007AAR_E_RBT_loc"
      unitRef="pure">0.0232</oef:AvgAnnlRtrPct>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000007007_Indexid_LB013_contentCd_ASTP-PRO_01"
      id="ixv-4175">
         Bloomberg U.S. 1-3 Year Government/Credit Bond Index
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007007_Indexid_LB013_contentCd_ASTP-PRO_01"
      decimals="4"
      id="ixv-101380"
      unitRef="pure">0.0436</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007007_Indexid_LB013_contentCd_ASTP-PRO_05"
      decimals="4"
      id="ixv-101381"
      unitRef="pure">0.0158</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007007_Indexid_LB013_contentCd_ASTP-PRO_AverageAnnualReturnSinceInception"
      decimals="4"
      id="ixv-101382"
      unitRef="pure">0.0166</oef:AvgAnnlRtrPct>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000007007_Indexid_LB001_contentCd_ASTP-PRO_01"
      id="ixv-4200">
         Bloomberg U.S. Aggregate Bond Index
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007007_Indexid_LB001_contentCd_ASTP-PRO_01"
      decimals="4"
      id="ixv-101383"
      unitRef="pure">0.0125</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007007_Indexid_LB001_contentCd_ASTP-PRO_05"
      decimals="4"
      id="ixv-101384"
      unitRef="pure">-0.0033</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007007_Indexid_LB001_contentCd_ASTP-PRO_AverageAnnualReturnSinceInception"
      decimals="4"
      id="ixv-101385"
      unitRef="pure">0.0087</oef:AvgAnnlRtrPct>
    <oef:AnnualReturnInceptionDate contextRef="Pid_S000007007_Cid_C000171437" id="ixv-4242">2016-07-12</oef:AnnualReturnInceptionDate>
    <oef:AnnualReturnInceptionDate contextRef="Pid_S000007007_Cid_C000171438" id="ixv-4256">2016-07-12</oef:AnnualReturnInceptionDate>
    <oef:AnnualReturnInceptionDate contextRef="Pid_S000007007_Cid_C000171439" id="ixv-4269">2016-07-12</oef:AnnualReturnInceptionDate>
    <oef:AnnualReturnInceptionDate contextRef="Pid_S000007007_Cid_C000171440" id="ixv-4282">2016-07-12</oef:AnnualReturnInceptionDate>
    <oef:AnnualReturnInceptionDate contextRef="Pid_S000007007_Cid_C000205020" id="ixv-4295">2018-10-02</oef:AnnualReturnInceptionDate>
    <oef:RiskReturnHeading
      contextRef="Pid_S000062237_contentCd_STB-PRO"
      id="ixv-10696">


     Fund Summary

     Fund:
     Fidelity&#xae; SAI Total Bond Fund

   </oef:RiskReturnHeading>
    <oef:ObjectiveHeading
      contextRef="Pid_S000062237_contentCd_STB-PRO"
      id="ixv-10705">


     Investment Objective


   </oef:ObjectiveHeading>
    <oef:ObjectivePrimaryTextBlock
      contextRef="Pid_S000062237_contentCd_STB-PRO"
      id="ixv-10710">


     Fidelity&#xae; SAI Total Bond Fund seeks a high level of current income.


   </oef:ObjectivePrimaryTextBlock>
    <oef:ExpenseHeading
      contextRef="Pid_S000062237_contentCd_STB-PRO"
      id="ixv-10715">


     Fee Table


   </oef:ExpenseHeading>
    <oef:ExpenseNarrativeTextBlock
      contextRef="Pid_S000062237_contentCd_STB-PRO"
      id="ixv-10721">


     The following table describes the fees and expenses that may be incurred when you buy, hold, and sell shares of the fund.

   </oef:ExpenseNarrativeTextBlock>
    <oef:ShareholderFeesCaption
      contextRef="Pid_S000062237_contentCd_STB-PRO"
      id="ixv-10731">


     Shareholder fees


   </oef:ShareholderFeesCaption>
    <oef:ShareholderFeeOther
      contextRef="Pid_S000062237_contentCd_STB-PRO"
      decimals="0"
      id="ixv-101386"
      unitRef="usd">0</oef:ShareholderFeeOther>
    <oef:OperatingExpensesCaption
      contextRef="Pid_S000062237_contentCd_STB-PRO"
      id="ixv-10746">


     Annual Operating Expenses


   </oef:OperatingExpensesCaption>
    <oef:ManagementFeesOverAssets
      contextRef="Pid_S000062237_Cid_C000201533"
      decimals="6"
      id="ixv-101387"
      unitRef="pure">0.0028</oef:ManagementFeesOverAssets>
    <oef:DistributionAndService12b1FeesOverAssets
      contextRef="Pid_S000062237_Cid_C000201533"
      decimals="6"
      id="ixv-101388"
      unitRef="pure">0</oef:DistributionAndService12b1FeesOverAssets>
    <oef:OtherExpensesOverAssets
      contextRef="Pid_S000062237_Cid_C000201533"
      decimals="6"
      id="ixv-101389"
      unitRef="pure">0.0001</oef:OtherExpensesOverAssets>
    <oef:ExpensesOverAssets
      contextRef="Pid_S000062237_Cid_C000201533"
      decimals="6"
      id="ixv-101390"
      unitRef="pure">0.0029</oef:ExpensesOverAssets>
    <oef:ExpenseExampleNarrativeTextBlock
      contextRef="Pid_S000062237_contentCd_STB-PRO"
      id="ixv-10793">




     This
     example

     helps compare the cost of investing in the fund with the cost of investing in other funds.

     Let's say, hypothetically, that the annual return for shares of the fund is 5% and that the fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated:

   </oef:ExpenseExampleNarrativeTextBlock>
    <oef:ExpenseExampleYear01
      contextRef="Pid_S000062237_Cid_C000201533"
      decimals="0"
      id="ixv-101391"
      unitRef="usd">30</oef:ExpenseExampleYear01>
    <oef:ExpenseExampleYear03
      contextRef="Pid_S000062237_Cid_C000201533"
      decimals="0"
      id="ixv-101392"
      unitRef="usd">93</oef:ExpenseExampleYear03>
    <oef:ExpenseExampleYear05
      contextRef="Pid_S000062237_Cid_C000201533"
      decimals="0"
      id="ixv-101393"
      unitRef="usd">163</oef:ExpenseExampleYear05>
    <oef:ExpenseExampleYear10
      contextRef="Pid_S000062237_Cid_C000201533"
      decimals="0"
      id="ixv-101394"
      unitRef="usd">368</oef:ExpenseExampleYear10>
    <oef:PortfolioTurnoverHeading
      contextRef="Pid_S000062237_contentCd_STB-PRO"
      id="ixv-10851">


     Portfolio Turnover


   </oef:PortfolioTurnoverHeading>
    <oef:PortfolioTurnoverTextBlock
      contextRef="Pid_S000062237_contentCd_STB-PRO"
      id="ixv-10856">


     The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was



       214


     % of the average value of its portfolio.


   </oef:PortfolioTurnoverTextBlock>
    <oef:PortfolioTurnoverRate
      contextRef="Pid_S000062237_contentCd_STB-PRO"
      decimals="4"
      id="ixv-101395"
      unitRef="pure">2.14</oef:PortfolioTurnoverRate>
    <oef:StrategyHeading
      contextRef="Pid_S000062237_contentCd_STB-PRO"
      id="ixv-10865">


     Principal Investment Strategies


   </oef:StrategyHeading>
    <oef:StrategyNarrativeTextBlock
      contextRef="Pid_S000062237_contentCd_STB-PRO"
      id="ixv-10870">




        Normally investing at least 80% of assets in debt securities of all types and repurchase agreements for those securities.


       Debt securities are used by issuers to borrow money. The issuer usually pays a fixed, variable, or floating rate of interest, and must repay the amount borrowed, usually at the maturity of the security. Debt securities include corporate bonds, government securities (including Treasury securities), repurchase agreements, money market securities, mortgage and other asset-backed securities, loans and loan participations, and other securities, such as hybrids and synthetic securities, believed to have debt-like characteristics (e.g., securities classified as Tier 2 Regulatory capital, securities that rank above share capital in an insolvency waterfall, securities with maturity dates and non-cancellable interest payment structures).&#160;
     A repurchase agreement is an agreement to buy a security at one price and a simultaneous agreement to sell it back at an agreed-upon price.
     Effective December 11, 2025, derivative instruments that provide investment exposure to the investments above or exposure to one or more market risk factors associated with such investments are included in the fund's 80% policy, consistent with the fund's investment policies and limitations with respect to investments in derivatives.
     &#160;

      Allocating assets across investment-grade, high yield, and emerging markets debt securities. Emerging markets include countries that have an emerging stock market as defined by MSCI, countries or markets with low- to middle-income economies as classified by the World Bank, and other countries or markets that the Adviser identifies as having similar emerging markets characteristics.
      Investing up to 20% of assets in lower-quality debt securities (those of less than investment-grade quality, also referred to as high yield debt securities or junk bonds).
      Managing the fund to have similar overall interest rate risk to the
        Bloomberg U.S. Aggregate Bond Index.
      Investing in domestic and foreign issuers.
      Allocating assets across different asset classes, market sectors, and maturities.
      Analyzing the credit quality of the issuer, the issuer's potential for success, the credit, currency, and economic risks of the security and its issuer, security-specific features, current and potential future valuation, and trading opportunities to select investments.
      Engaging in transactions that have a leveraging effect on the fund, including investments in derivatives - such as swaps (interest rate, total return, and credit default), options, and futures contracts - and forward-settling securities, to adjust the fund's risk exposure.


   </oef:StrategyNarrativeTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000062237_contentCd_STB-PRO_RiskMember_InterestRateChangesMember"
      id="ixv-10908">



      Interest Rate Changes.

     Interest rate increases can cause the price of a debt security to decrease.

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000062237_contentCd_STB-PRO_RiskMember_ForeignExposureMember"
      id="ixv-10917">



      Foreign Exposure.

     Foreign markets, particularly emerging markets, can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market.
     Foreign exchange rates also can be extremely volatile.

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000062237_contentCd_STB-PRO_RiskMember_PrepaymentMember"
      id="ixv-10928">



      Prepayment.

     The ability of an issuer of a debt security to repay principal prior to a security's maturity can cause greater price volatility if interest rates change.

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000062237_contentCd_STB-PRO_RiskMember_IssuerSpecificChangesMember"
      id="ixv-10937">



      Issuer-Specific Changes.

     The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole.
     A decline in the credit quality of an issuer or a provider of credit support (such as guarantees) or a maturity-shortening structure (such as demand and put features) for a security can cause the price of a security to decrease.
     Lower-quality debt securities (those of less than investment-grade quality, also referred to as high yield debt securities or junk bonds) and certain types of other securities involve greater risk of default or price changes due to changes in the credit quality of the issuer.
     The value of lower-quality debt securities and certain types of other securities can be more volatile due to increased sensitivity to adverse issuer, political, regulatory, market, or economic developments and can be difficult to resell.

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000062237_contentCd_STB-PRO_RiskMember_LeverageRiskMember"
      id="ixv-10956">



      Leverage Risk.

     Leverage can increase market exposure, magnify investment risks, and cause losses to be realized more quickly.

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000062237_contentCd_STB-PRO_RiskMember_HighPortfolioTurnoverMember"
      id="ixv-10965">



      High Portfolio Turnover.

     High portfolio turnover (more than 100%) may result in increased transaction costs and potentially higher capital gains or losses. The effects of higher than normal portfolio turnover may adversely affect the fund's performance.



   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000062237_contentCd_STB-PRO_RiskMember_RiskNotInsuredDepositoryInstitutionMember"
      id="ixv-10975">


     An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency

     .


   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000062237_contentCd_STB-PRO_RiskMember_RiskLoseMoneyMember"
      id="ixv-10983">


     &#160;

     You could lose money by investing in the fund.


   </oef:RiskTextBlock>
    <oef:BarChartAndPerformanceTableHeading
      contextRef="Pid_S000062237_contentCd_STB-PRO"
      id="ixv-10992">


     Performance


   </oef:BarChartAndPerformanceTableHeading>
    <oef:PerformanceNarrativeTextBlock
      contextRef="Pid_S000062237_contentCd_STB-PRO"
      id="ixv-10997">



       The following information is intended to help you understand the risks of investing in the fund.


      The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index


      over various periods of time.



     The


     index


     description appears
      in the "Additional Index Information" section of the prospectus.



      Past performance (before and after taxes) is not an indication of future performance.


     Visit



      www.fidelity.com


     for more recent performance information.

   </oef:PerformanceNarrativeTextBlock>
    <oef:PerformanceInformationIllustratesVariabilityOfReturns
      contextRef="Pid_S000062237_contentCd_STB-PRO"
      id="ixv-11003">

      The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index


      over various periods of time.

     </oef:PerformanceInformationIllustratesVariabilityOfReturns>
    <oef:PerformancePastDoesNotIndicateFuture
      contextRef="Pid_S000062237_contentCd_STB-PRO"
      id="ixv-11017">

      Past performance (before and after taxes) is not an indication of future performance.

     </oef:PerformancePastDoesNotIndicateFuture>
    <oef:PerformanceAvailabilityWebSiteAddress
      contextRef="Pid_S000062237_contentCd_STB-PRO"
      id="ixv-11023">

      www.fidelity.com
     </oef:PerformanceAvailabilityWebSiteAddress>
    <oef:BarChartHeading
      contextRef="Pid_S000062237_contentCd_STB-PRO"
      id="ixv-11028">


     Year-by-Year Returns

   </oef:BarChartHeading>
    <oef:AnnlRtrPct
      contextRef="Pid_S000062237_Cid_C000201533_2019"
      decimals="INF"
      id="ixv-101396"
      unitRef="pure">0.0987</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000062237_Cid_C000201533_2020"
      decimals="INF"
      id="ixv-101397"
      unitRef="pure">0.0905</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000062237_Cid_C000201533_2021"
      decimals="INF"
      id="ixv-101398"
      unitRef="pure">0.0010</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000062237_Cid_C000201533_2022"
      decimals="INF"
      id="ixv-101399"
      unitRef="pure">-0.1261</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000062237_Cid_C000201533_2023"
      decimals="INF"
      id="ixv-101400"
      unitRef="pure">0.0731</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000062237_Cid_C000201533_2024"
      decimals="INF"
      id="ixv-101401"
      unitRef="pure">0.0291</oef:AnnlRtrPct>
    <oef:HighestQuarterlyReturnLabel
      contextRef="Pid_S000062237_contentCd_STB-PRO"
      id="ixv-11126">
          &#160;&#160;&#160;Highest Quarter Return
        </oef:HighestQuarterlyReturnLabel>
    <oef:BarChartHighestQuarterlyReturn
      contextRef="Pid_S000062237_contentCd_STB-PRO"
      decimals="4"
      id="ixv-101402"
      unitRef="pure">0.0683</oef:BarChartHighestQuarterlyReturn>
    <oef:BarChartHighestQuarterlyReturnDate
      contextRef="Pid_S000062237_contentCd_STB-PRO"
      id="ixv-11136">2023-12-31</oef:BarChartHighestQuarterlyReturnDate>
    <oef:LowestQuarterlyReturnLabel
      contextRef="Pid_S000062237_contentCd_STB-PRO"
      id="ixv-11141">
          &#160;&#160;&#160;Lowest Quarter Return
        </oef:LowestQuarterlyReturnLabel>
    <oef:BarChartLowestQuarterlyReturn
      contextRef="Pid_S000062237_contentCd_STB-PRO"
      decimals="4"
      id="ixv-101403"
      unitRef="pure">-0.0578</oef:BarChartLowestQuarterlyReturn>
    <oef:BarChartLowestQuarterlyReturnDate
      contextRef="Pid_S000062237_contentCd_STB-PRO"
      id="ixv-11152">2022-06-30</oef:BarChartLowestQuarterlyReturnDate>
    <oef:YearToDateReturnLabel
      contextRef="Pid_S000062237_contentCd_STB-PRO"
      id="ixv-11157">
          &#160;&#160;&#160;Year-to-Date Return
        </oef:YearToDateReturnLabel>
    <oef:BarChartYearToDateReturn
      contextRef="Pid_S000062237_contentCd_STB-PRO"
      decimals="4"
      id="ixv-101404"
      unitRef="pure">0.0652</oef:BarChartYearToDateReturn>
    <oef:BarChartYearToDateReturnDate
      contextRef="Pid_S000062237_contentCd_STB-PRO"
      id="ixv-11167">2025-09-30</oef:BarChartYearToDateReturnDate>
    <oef:PerformanceTableHeading
      contextRef="Pid_S000062237_contentCd_STB-PRO"
      id="ixv-11172">


     Average Annual Returns


   </oef:PerformanceTableHeading>
    <oef:PerformanceTableNarrativeTextBlock
      contextRef="Pid_S000062237_contentCd_STB-PRO"
      id="ixv-11177">




      After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes.



     Actual after-tax returns may differ depending on your individual circumstances.



      The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan).





      Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.




   </oef:PerformanceTableNarrativeTextBlock>
    <oef:PerformanceTableUsesHighestFederalRate
      contextRef="Pid_S000062237_contentCd_STB-PRO"
      id="ixv-11180">

      After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes.

     </oef:PerformanceTableUsesHighestFederalRate>
    <oef:PerformanceTableNotRelevantToTaxDeferred
      contextRef="Pid_S000062237_contentCd_STB-PRO"
      id="ixv-11187">

      The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan).

     </oef:PerformanceTableNotRelevantToTaxDeferred>
    <oef:PerformanceTableExplanationAfterTaxHigher
      contextRef="Pid_S000062237_contentCd_STB-PRO"
      id="ixv-11192">

      Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

     </oef:PerformanceTableExplanationAfterTaxHigher>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000062237_Cid_C000201533_ReturnBeforeTaxes_01"
      id="ixv-11238">
         Return Before Taxes
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000062237_Cid_C000201533_ReturnBeforeTaxes_01"
      decimals="4"
      id="ixv-101405"
      unitRef="pure">0.0291</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000062237_Cid_C000201533_ReturnBeforeTaxes_05"
      decimals="4"
      id="ixv-101406"
      unitRef="pure">0.0105</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000062237_Cid_C000201533_ReturnBeforeTaxes_AverageAnnualReturnSinceInception"
      decimals="4"
      id="footnoteSTB-PROS000062237AAR_A_RBT_loc"
      unitRef="pure">0.0256</oef:AvgAnnlRtrPct>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000062237_Cid_C000201533_AfterTaxesOnDistributions_01"
      id="ixv-11254">
         Return After Taxes on Distributions
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000062237_Cid_C000201533_AfterTaxesOnDistributions_01"
      decimals="4"
      id="ixv-101408"
      unitRef="pure">0.0115</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000062237_Cid_C000201533_AfterTaxesOnDistributions_05"
      decimals="4"
      id="ixv-101409"
      unitRef="pure">-0.0060</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000062237_Cid_C000201533_AfterTaxesOnDistributions_AverageAnnualReturnSinceInception"
      decimals="4"
      id="footnoteSTB-PROS000062237AAR_A_ATD_loc"
      unitRef="pure">0.0084</oef:AvgAnnlRtrPct>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000062237_Cid_C000201533_AfterTaxesOnDistributionsAndSales_01"
      id="ixv-11271">
         Return After Taxes on Distributions and Sale of Fund Shares
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000062237_Cid_C000201533_AfterTaxesOnDistributionsAndSales_01"
      decimals="4"
      id="ixv-101411"
      unitRef="pure">0.0188</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000062237_Cid_C000201533_AfterTaxesOnDistributionsAndSales_05"
      decimals="4"
      id="ixv-101412"
      unitRef="pure">0.0018</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000062237_Cid_C000201533_AfterTaxesOnDistributionsAndSales_AverageAnnualReturnSinceInception"
      decimals="4"
      id="footnoteSTB-PROS000062237AAR_A_ATDS_loc"
      unitRef="pure">0.0129</oef:AvgAnnlRtrPct>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000062237_Indexid_LB001_contentCd_STB-PRO_01"
      id="ixv-11288">
         Bloomberg U.S. Aggregate Bond Index
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000062237_Indexid_LB001_contentCd_STB-PRO_01"
      decimals="4"
      id="ixv-101414"
      unitRef="pure">0.0125</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000062237_Indexid_LB001_contentCd_STB-PRO_05"
      decimals="4"
      id="ixv-101415"
      unitRef="pure">-0.0033</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000062237_Indexid_LB001_contentCd_STB-PRO_AverageAnnualReturnSinceInception"
      decimals="4"
      id="ixv-101416"
      unitRef="pure">0.0145</oef:AvgAnnlRtrPct>
    <oef:AnnualReturnInceptionDate contextRef="Pid_S000062237_Cid_C000201533" id="ixv-11330">2018-10-25</oef:AnnualReturnInceptionDate>
    <oef:RiskReturnHeading
      contextRef="Pid_S000007004_contentCd_IGB-PRO"
      id="ixv-12937">


     Fund Summary

     Fund /Class:
     Fidelity&#xae; Investment Grade Bond Fund
     /Fidelity&#xae; Investment Grade Bond Fund

   </oef:RiskReturnHeading>
    <oef:ObjectiveHeading
      contextRef="Pid_S000007004_contentCd_IGB-PRO"
      id="ixv-12950">


     Investment Objective


   </oef:ObjectiveHeading>
    <oef:ObjectivePrimaryTextBlock
      contextRef="Pid_S000007004_contentCd_IGB-PRO"
      id="ixv-12955">


     Fidelity&#xae; Investment Grade Bond Fund seeks a high level of current income.


   </oef:ObjectivePrimaryTextBlock>
    <oef:ExpenseHeading
      contextRef="Pid_S000007004_contentCd_IGB-PRO"
      id="ixv-12960">


     Fee Table


   </oef:ExpenseHeading>
    <oef:ExpenseNarrativeTextBlock
      contextRef="Pid_S000007004_contentCd_IGB-PRO"
      id="ixv-12966">


     The following table describes the fees and expenses that may be incurred when you buy, hold, and sell shares of the fund. You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and examples below.

   </oef:ExpenseNarrativeTextBlock>
    <oef:ShareholderFeesCaption
      contextRef="Pid_S000007004_contentCd_IGB-PRO"
      id="ixv-12977">


     Shareholder fees


   </oef:ShareholderFeesCaption>
    <oef:ShareholderFeeOther
      contextRef="Pid_S000007004_contentCd_IGB-PRO"
      decimals="0"
      id="ixv-101417"
      unitRef="usd">0</oef:ShareholderFeeOther>
    <oef:OperatingExpensesCaption
      contextRef="Pid_S000007004_contentCd_IGB-PRO"
      id="ixv-12992">


     Annual Operating Expenses


   </oef:OperatingExpensesCaption>
    <oef:ManagementFeesOverAssets
      contextRef="Pid_S000007004_Cid_C000019120"
      decimals="6"
      id="ixv-101418"
      unitRef="pure">0.0028</oef:ManagementFeesOverAssets>
    <oef:DistributionAndService12b1FeesOverAssets
      contextRef="Pid_S000007004_Cid_C000019120"
      decimals="6"
      id="ixv-101419"
      unitRef="pure">0</oef:DistributionAndService12b1FeesOverAssets>
    <oef:OtherExpensesOverAssets
      contextRef="Pid_S000007004_Cid_C000019120"
      decimals="6"
      id="ixv-101420"
      unitRef="pure">0.0017</oef:OtherExpensesOverAssets>
    <oef:ExpensesOverAssets
      contextRef="Pid_S000007004_Cid_C000019120"
      decimals="6"
      id="ixv-101421"
      unitRef="pure">0.0045</oef:ExpensesOverAssets>
    <oef:ExpenseExampleNarrativeTextBlock
      contextRef="Pid_S000007004_contentCd_IGB-PRO"
      id="ixv-13039">




     This
     example

     helps compare the cost of investing in the fund with the cost of investing in other funds.

     Let's say, hypothetically, that the annual return for shares of the fund is 5% and that the fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated:

   </oef:ExpenseExampleNarrativeTextBlock>
    <oef:ExpenseExampleYear01
      contextRef="Pid_S000007004_Cid_C000019120"
      decimals="0"
      id="ixv-101422"
      unitRef="usd">46</oef:ExpenseExampleYear01>
    <oef:ExpenseExampleYear03
      contextRef="Pid_S000007004_Cid_C000019120"
      decimals="0"
      id="ixv-101423"
      unitRef="usd">144</oef:ExpenseExampleYear03>
    <oef:ExpenseExampleYear05
      contextRef="Pid_S000007004_Cid_C000019120"
      decimals="0"
      id="ixv-101424"
      unitRef="usd">252</oef:ExpenseExampleYear05>
    <oef:ExpenseExampleYear10
      contextRef="Pid_S000007004_Cid_C000019120"
      decimals="0"
      id="ixv-101425"
      unitRef="usd">567</oef:ExpenseExampleYear10>
    <oef:PortfolioTurnoverHeading
      contextRef="Pid_S000007004_contentCd_IGB-PRO"
      id="ixv-13097">


     Portfolio Turnover


   </oef:PortfolioTurnoverHeading>
    <oef:PortfolioTurnoverTextBlock
      contextRef="Pid_S000007004_contentCd_IGB-PRO"
      id="ixv-13102">


     The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was



       196


     % of the average value of its portfolio.


   </oef:PortfolioTurnoverTextBlock>
    <oef:PortfolioTurnoverRate
      contextRef="Pid_S000007004_contentCd_IGB-PRO"
      decimals="4"
      id="ixv-101426"
      unitRef="pure">1.96</oef:PortfolioTurnoverRate>
    <oef:StrategyHeading
      contextRef="Pid_S000007004_contentCd_IGB-PRO"
      id="ixv-13111">


     Principal Investment Strategies


   </oef:StrategyHeading>
    <oef:StrategyNarrativeTextBlock
      contextRef="Pid_S000007004_contentCd_IGB-PRO"
      id="ixv-13116">




        Normally investing at least 80% of assets in investment-grade debt securities (those of medium and high quality) of all types and repurchase agreements for those securities.

     Debt securities are used by issuers to borrow money. The issuer usually pays a fixed, variable, or floating rate of interest, and must repay the amount borrowed, usually at the maturity of the security. Debt securities include corporate bonds, government securities (including Treasury securities), repurchase agreements, money market securities, mortgage and other asset-backed securities, loans and loan participations, and other securities, such as hybrids and synthetic securities, believed to have debt-like characteristics (e.g., securities classified as Tier 2 Regulatory capital, securities that rank above share capital in an insolvency waterfall, securities with maturity dates and non-cancellable interest payment structures).&#160;
     Investment grade securities in which the fund invests include securities or issuers rated at least BBB- or its equivalent by at least one nationally recognized statistical ratings organization (NRSRO), or, if unrated, determined by the Adviser to be of comparable quality.
     A repurchase agreement is an agreement to buy a security at one price and a simultaneous agreement to sell it back at an agreed-upon price.
     Effective December 11, 2025, derivative instruments that provide investment exposure to the investments above or exposure to one or more market risk factors associated with such investments are included in the fund's 80% policy, consistent with the fund's investment policies and limitations with respect to investments in derivatives.

      &#160;
      Managing the fund to have similar overall interest rate risk to the Bloomberg U.S. Aggregate Bond Index.
      Allocating assets across different market sectors and maturities.
      Investing in domestic and foreign issuers.
      Analyzing the credit quality of the issuer, security-specific features, current and potential future valuation, and trading opportunities to select investments.
      Investing in lower-quality debt securities (those of less than investment-grade quality, also referred to as high yield debt securities or junk bonds).
      Engaging in transactions that have a leveraging effect on the fund, including investments in derivatives - such as swaps (interest rate, total return, and credit default), options, and futures contracts - and forward-settling securities, to adjust the fund's risk exposure.
      Investing in Fidelity's Central funds (specialized investment vehicles used by Fidelity&#xae; funds to invest in particular security types or investment disciplines) consistent with the asset classes discussed above.


   </oef:StrategyNarrativeTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000007004_contentCd_IGB-PRO_RiskMember_InterestRateChangesMember"
      id="ixv-13153">



      Interest Rate Changes.

     Interest rate increases can cause the price of a debt security to decrease.

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000007004_contentCd_IGB-PRO_RiskMember_ForeignExposureMember"
      id="ixv-13162">



      Foreign Exposure.

     Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market.

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000007004_contentCd_IGB-PRO_RiskMember_PrepaymentMember"
      id="ixv-13171">



      Prepayment.

     The ability of an issuer of a debt security to repay principal prior to a security's maturity can cause greater price volatility if interest rates change.

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000007004_contentCd_IGB-PRO_RiskMember_IssuerSpecificChangesMember"
      id="ixv-13180">



      Issuer-Specific Changes.

     The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole.
     A decline in the credit quality of an issuer or a provider of credit support (such as guarantees) or a maturity-shortening structure (such as demand and put features) for a security can cause the price of a security to decrease.
     Lower-quality debt securities (those of less than investment-grade quality, also referred to as high yield debt securities or junk bonds) involve greater risk of default or price changes due to changes in the credit quality of the issuer. The value of lower-quality debt securities can be more volatile due to increased sensitivity to adverse issuer, political, regulatory, market, or economic developments.

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000007004_contentCd_IGB-PRO_RiskMember_LeverageRiskMember"
      id="ixv-13197">



      Leverage Risk.

     Leverage can increase market exposure, magnify investment risks, and cause losses to be realized more quickly.

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000007004_contentCd_IGB-PRO_RiskMember_HighPortfolioTurnoverMember"
      id="ixv-13206">



      High Portfolio Turnover.

     High portfolio turnover (more than 100%) may result in increased transaction costs and potentially higher capital gains or losses. The effects of higher than normal portfolio turnover may adversely affect the fund's performance.



   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000007004_contentCd_IGB-PRO_RiskMember_RiskNotInsuredDepositoryInstitutionMember"
      id="ixv-13216">


     An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency

     .


   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000007004_contentCd_IGB-PRO_RiskMember_RiskLoseMoneyMember"
      id="ixv-13224">


     &#160;

     You could lose money by investing in the fund.


   </oef:RiskTextBlock>
    <oef:BarChartAndPerformanceTableHeading
      contextRef="Pid_S000007004_contentCd_IGB-PRO"
      id="ixv-13233">


     Performance


   </oef:BarChartAndPerformanceTableHeading>
    <oef:PerformanceNarrativeTextBlock
      contextRef="Pid_S000007004_contentCd_IGB-PRO"
      id="ixv-13238">



       The following information is intended to help you understand the risks of investing in the fund.


      The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index over various periods of time.



     The index description appears in the "Additional Index Information" section of the prospectus.



      Past performance (before and after taxes) is not an indication of future performance.


     Visit



      www.fidelity.com


     for more recent performance information.

   </oef:PerformanceNarrativeTextBlock>
    <oef:PerformanceInformationIllustratesVariabilityOfReturns
      contextRef="Pid_S000007004_contentCd_IGB-PRO"
      id="ixv-13244">

      The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index over various periods of time.

     </oef:PerformanceInformationIllustratesVariabilityOfReturns>
    <oef:PerformancePastDoesNotIndicateFuture
      contextRef="Pid_S000007004_contentCd_IGB-PRO"
      id="ixv-13251">

      Past performance (before and after taxes) is not an indication of future performance.

     </oef:PerformancePastDoesNotIndicateFuture>
    <oef:PerformanceAvailabilityWebSiteAddress
      contextRef="Pid_S000007004_contentCd_IGB-PRO"
      id="ixv-13257">

      www.fidelity.com
     </oef:PerformanceAvailabilityWebSiteAddress>
    <oef:BarChartHeading
      contextRef="Pid_S000007004_contentCd_IGB-PRO"
      id="ixv-13262">


     Year-by-Year Returns

   </oef:BarChartHeading>
    <oef:AnnlRtrPct
      contextRef="Pid_S000007004_Cid_C000019120_2015"
      decimals="INF"
      id="ixv-101427"
      unitRef="pure">-0.0157</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000007004_Cid_C000019120_2016"
      decimals="INF"
      id="ixv-101428"
      unitRef="pure">0.0533</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000007004_Cid_C000019120_2017"
      decimals="INF"
      id="ixv-101429"
      unitRef="pure">0.0391</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000007004_Cid_C000019120_2018"
      decimals="INF"
      id="ixv-101430"
      unitRef="pure">-0.0036</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000007004_Cid_C000019120_2019"
      decimals="INF"
      id="ixv-101431"
      unitRef="pure">0.0981</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000007004_Cid_C000019120_2020"
      decimals="INF"
      id="ixv-101432"
      unitRef="pure">0.0990</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000007004_Cid_C000019120_2021"
      decimals="INF"
      id="ixv-101433"
      unitRef="pure">-0.0089</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000007004_Cid_C000019120_2022"
      decimals="INF"
      id="ixv-101434"
      unitRef="pure">-0.1348</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000007004_Cid_C000019120_2023"
      decimals="INF"
      id="ixv-101435"
      unitRef="pure">0.0649</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000007004_Cid_C000019120_2024"
      decimals="INF"
      id="ixv-101436"
      unitRef="pure">0.0159</oef:AnnlRtrPct>
    <oef:HighestQuarterlyReturnLabel
      contextRef="Pid_S000007004_contentCd_IGB-PRO"
      id="ixv-13375">
          &#160;&#160;&#160;Highest Quarter Return
        </oef:HighestQuarterlyReturnLabel>
    <oef:BarChartHighestQuarterlyReturn
      contextRef="Pid_S000007004_contentCd_IGB-PRO"
      decimals="4"
      id="ixv-101437"
      unitRef="pure">0.0689</oef:BarChartHighestQuarterlyReturn>
    <oef:BarChartHighestQuarterlyReturnDate
      contextRef="Pid_S000007004_contentCd_IGB-PRO"
      id="ixv-13385">2023-12-31</oef:BarChartHighestQuarterlyReturnDate>
    <oef:LowestQuarterlyReturnLabel
      contextRef="Pid_S000007004_contentCd_IGB-PRO"
      id="ixv-13390">
          &#160;&#160;&#160;Lowest Quarter Return
        </oef:LowestQuarterlyReturnLabel>
    <oef:BarChartLowestQuarterlyReturn
      contextRef="Pid_S000007004_contentCd_IGB-PRO"
      decimals="4"
      id="ixv-101438"
      unitRef="pure">-0.0578</oef:BarChartLowestQuarterlyReturn>
    <oef:BarChartLowestQuarterlyReturnDate
      contextRef="Pid_S000007004_contentCd_IGB-PRO"
      id="ixv-13401">2022-03-31</oef:BarChartLowestQuarterlyReturnDate>
    <oef:YearToDateReturnLabel
      contextRef="Pid_S000007004_contentCd_IGB-PRO"
      id="ixv-13406">
          &#160;&#160;&#160;Year-to-Date Return
        </oef:YearToDateReturnLabel>
    <oef:BarChartYearToDateReturn
      contextRef="Pid_S000007004_contentCd_IGB-PRO"
      decimals="4"
      id="ixv-101439"
      unitRef="pure">0.0644</oef:BarChartYearToDateReturn>
    <oef:BarChartYearToDateReturnDate
      contextRef="Pid_S000007004_contentCd_IGB-PRO"
      id="ixv-13416">2025-09-30</oef:BarChartYearToDateReturnDate>
    <oef:PerformanceTableHeading
      contextRef="Pid_S000007004_contentCd_IGB-PRO"
      id="ixv-13421">


     Average Annual Returns


   </oef:PerformanceTableHeading>
    <oef:PerformanceTableNarrativeTextBlock
      contextRef="Pid_S000007004_contentCd_IGB-PRO"
      id="ixv-13426">




      After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes.



     Actual after-tax returns may differ depending on your individual circumstances.



      The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan).





      Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.




   </oef:PerformanceTableNarrativeTextBlock>
    <oef:PerformanceTableUsesHighestFederalRate
      contextRef="Pid_S000007004_contentCd_IGB-PRO"
      id="ixv-13429">

      After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes.

     </oef:PerformanceTableUsesHighestFederalRate>
    <oef:PerformanceTableNotRelevantToTaxDeferred
      contextRef="Pid_S000007004_contentCd_IGB-PRO"
      id="ixv-13436">

      The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan).

     </oef:PerformanceTableNotRelevantToTaxDeferred>
    <oef:PerformanceTableExplanationAfterTaxHigher
      contextRef="Pid_S000007004_contentCd_IGB-PRO"
      id="ixv-13441">

      Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

     </oef:PerformanceTableExplanationAfterTaxHigher>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000007004_Cid_C000019120_ReturnBeforeTaxes_01"
      id="ixv-13486">
         Return Before Taxes
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007004_Cid_C000019120_ReturnBeforeTaxes_01"
      decimals="4"
      id="ixv-101440"
      unitRef="pure">0.0159</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007004_Cid_C000019120_ReturnBeforeTaxes_05"
      decimals="4"
      id="ixv-101441"
      unitRef="pure">0.0039</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007004_Cid_C000019120_ReturnBeforeTaxes_10"
      decimals="4"
      id="ixv-101442"
      unitRef="pure">0.0186</oef:AvgAnnlRtrPct>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000007004_Cid_C000019120_AfterTaxesOnDistributions_01"
      id="ixv-13501">
         Return After Taxes on Distributions
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007004_Cid_C000019120_AfterTaxesOnDistributions_01"
      decimals="4"
      id="ixv-101443"
      unitRef="pure">0.0019</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007004_Cid_C000019120_AfterTaxesOnDistributions_05"
      decimals="4"
      id="ixv-101444"
      unitRef="pure">-0.0089</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007004_Cid_C000019120_AfterTaxesOnDistributions_10"
      decimals="4"
      id="ixv-101445"
      unitRef="pure">0.0065</oef:AvgAnnlRtrPct>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000007004_Cid_C000019120_AfterTaxesOnDistributionsAndSales_01"
      id="ixv-13517">
         Return After Taxes on Distributions and Sale of Fund Shares
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007004_Cid_C000019120_AfterTaxesOnDistributionsAndSales_01"
      decimals="4"
      id="ixv-101446"
      unitRef="pure">0.0115</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007004_Cid_C000019120_AfterTaxesOnDistributionsAndSales_05"
      decimals="4"
      id="ixv-101447"
      unitRef="pure">-0.0019</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007004_Cid_C000019120_AfterTaxesOnDistributionsAndSales_10"
      decimals="4"
      id="ixv-101448"
      unitRef="pure">0.0092</oef:AvgAnnlRtrPct>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000007004_Indexid_LB001_contentCd_IGB-PRO_01"
      id="ixv-13534">
         Bloomberg U.S. Aggregate Bond Index
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007004_Indexid_LB001_contentCd_IGB-PRO_01"
      decimals="4"
      id="ixv-101449"
      unitRef="pure">0.0125</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007004_Indexid_LB001_contentCd_IGB-PRO_05"
      decimals="4"
      id="ixv-101450"
      unitRef="pure">-0.0033</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007004_Indexid_LB001_contentCd_IGB-PRO_10"
      decimals="4"
      id="ixv-101451"
      unitRef="pure">0.0135</oef:AvgAnnlRtrPct>
    <oef:RiskReturnHeading
      contextRef="Pid_S000007004_contentCd_AIGB-PRO"
      id="ixv-15647">


     Fund Summary

     Fund /Class:
     Fidelity&#xae; Investment Grade Bond Fund
     /Fidelity Advisor&#xae; Investment Grade Bond Fund A, M, C, I, Z &#160;

   </oef:RiskReturnHeading>
    <oef:ObjectiveHeading
      contextRef="Pid_S000007004_contentCd_AIGB-PRO"
      id="ixv-15662">


     Investment Objective


   </oef:ObjectiveHeading>
    <oef:ObjectivePrimaryTextBlock
      contextRef="Pid_S000007004_contentCd_AIGB-PRO"
      id="ixv-15667">


     Fidelity&#xae; Investment Grade Bond Fund seeks a high level of current income.


   </oef:ObjectivePrimaryTextBlock>
    <oef:ExpenseHeading
      contextRef="Pid_S000007004_contentCd_AIGB-PRO"
      id="ixv-15672">


     Fee Table


   </oef:ExpenseHeading>
    <oef:ExpenseNarrativeTextBlock
      contextRef="Pid_S000007004_contentCd_AIGB-PRO"
      id="ixv-15678">


     The following table describes the fees and expenses that may be incurred when you buy, hold, and sell shares of the fund. You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and examples below.


      You may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $


        50,000


      in the fund or certain other Fidelity

      &#xae;

      funds. More information about these and other discounts is available from your investment professional and in the "Fund Distribution" section beginning on page


      35
       of the prospectus



     and in

     the sales charge

     waiver appendix to

     the prospectus.

   </oef:ExpenseNarrativeTextBlock>
    <oef:ExpenseBreakpointDiscounts
      contextRef="Pid_S000007004_contentCd_AIGB-PRO"
      id="ixv-15684">

      You may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $


        50,000


      in the fund or certain other Fidelity

      &#xae;

      funds. More information about these and other discounts is available from your investment professional and in the "Fund Distribution" section beginning on page


      35
       of the prospectus

     </oef:ExpenseBreakpointDiscounts>
    <oef:ExpenseBreakpointMinimumInvestmentRequiredAmount
      contextRef="Pid_S000007004_contentCd_AIGB-PRO"
      decimals="0"
      id="ixv-101452"
      unitRef="usd">50000</oef:ExpenseBreakpointMinimumInvestmentRequiredAmount>
    <oef:ShareholderFeesCaption
      contextRef="Pid_S000007004_contentCd_AIGB-PRO"
      id="ixv-15708">


     Shareholder fees


   </oef:ShareholderFeesCaption>
    <oef:MaximumCumulativeSalesChargeOverOfferingPrice
      contextRef="Pid_S000007004_Cid_C000019121"
      decimals="4"
      id="ixv-101453"
      unitRef="pure">0.0400</oef:MaximumCumulativeSalesChargeOverOfferingPrice>
    <oef:MaximumCumulativeSalesChargeOverOfferingPrice
      contextRef="Pid_S000007004_Cid_C000019124"
      decimals="4"
      id="ixv-101454"
      unitRef="pure">0.0400</oef:MaximumCumulativeSalesChargeOverOfferingPrice>
    <oef:MaximumCumulativeSalesChargeOverOfferingPrice
      contextRef="Pid_S000007004_Cid_C000019123"
      decimals="4"
      id="ixv-101455"
      unitRef="pure">0</oef:MaximumCumulativeSalesChargeOverOfferingPrice>
    <oef:MaximumCumulativeSalesChargeOverOfferingPrice
      contextRef="Pid_S000007004_Cid_C000019125"
      decimals="4"
      id="ixv-101456"
      unitRef="pure">0</oef:MaximumCumulativeSalesChargeOverOfferingPrice>
    <oef:MaximumCumulativeSalesChargeOverOfferingPrice
      contextRef="Pid_S000007004_Cid_C000205019"
      decimals="4"
      id="ixv-101457"
      unitRef="pure">0</oef:MaximumCumulativeSalesChargeOverOfferingPrice>
    <oef:MaximumDeferredSalesChargeOverOther
      contextRef="Pid_S000007004_Cid_C000019121"
      decimals="4"
      id="footnoteAIGB-PROS000007004SHF_AC000019121"
      unitRef="pure">0</oef:MaximumDeferredSalesChargeOverOther>
    <oef:MaximumDeferredSalesChargeOverOther
      contextRef="Pid_S000007004_Cid_C000019124"
      decimals="4"
      id="footnoteAIGB-PROS000007004SHF_AC000019124"
      unitRef="pure">0</oef:MaximumDeferredSalesChargeOverOther>
    <oef:MaximumDeferredSalesChargeOverOther
      contextRef="Pid_S000007004_Cid_C000019123"
      decimals="4"
      id="footnoteAIGB-PROS000007004SHF_BC000019123"
      unitRef="pure">0.0100</oef:MaximumDeferredSalesChargeOverOther>
    <oef:MaximumDeferredSalesChargeOverOther
      contextRef="Pid_S000007004_Cid_C000019125"
      decimals="4"
      id="ixv-101461"
      unitRef="pure">0</oef:MaximumDeferredSalesChargeOverOther>
    <oef:MaximumDeferredSalesChargeOverOther
      contextRef="Pid_S000007004_Cid_C000205019"
      decimals="4"
      id="ixv-101462"
      unitRef="pure">0</oef:MaximumDeferredSalesChargeOverOther>
    <oef:ExpensesDeferredChargesTextBlock
      contextRef="Pid_S000007004_contentCd_AIGB-PRO"
      id="ixv-15814">

      Class A and Class M purchases of $1 million or more will not be subject to a front-end sales charge. Such Class A and Class M purchases may be subject, upon redemption, to a contingent deferred sales charge (CDSC) of 0.75% and 0.25%, respectively.

     </oef:ExpensesDeferredChargesTextBlock>
    <oef:ExpensesDeferredChargesTextBlock contextRef="Pid_S000007004_Cid_C000019123" id="ixv-15824">

      On Class C shares redeemed less than one year after purchase.

     </oef:ExpensesDeferredChargesTextBlock>
    <oef:OperatingExpensesCaption
      contextRef="Pid_S000007004_contentCd_AIGB-PRO"
      id="ixv-15829">


     Annual Operating Expenses


   </oef:OperatingExpensesCaption>
    <oef:ManagementFeesOverAssets
      contextRef="Pid_S000007004_Cid_C000019121"
      decimals="6"
      id="ixv-101463"
      unitRef="pure">0.0028</oef:ManagementFeesOverAssets>
    <oef:ManagementFeesOverAssets
      contextRef="Pid_S000007004_Cid_C000019124"
      decimals="6"
      id="ixv-101464"
      unitRef="pure">0.0028</oef:ManagementFeesOverAssets>
    <oef:ManagementFeesOverAssets
      contextRef="Pid_S000007004_Cid_C000019123"
      decimals="6"
      id="ixv-101465"
      unitRef="pure">0.0028</oef:ManagementFeesOverAssets>
    <oef:ManagementFeesOverAssets
      contextRef="Pid_S000007004_Cid_C000019125"
      decimals="6"
      id="ixv-101466"
      unitRef="pure">0.0028</oef:ManagementFeesOverAssets>
    <oef:ManagementFeesOverAssets
      contextRef="Pid_S000007004_Cid_C000205019"
      decimals="6"
      id="ixv-101467"
      unitRef="pure">0.0028</oef:ManagementFeesOverAssets>
    <oef:DistributionAndService12b1FeesOverAssets
      contextRef="Pid_S000007004_Cid_C000019121"
      decimals="6"
      id="ixv-101468"
      unitRef="pure">0.0025</oef:DistributionAndService12b1FeesOverAssets>
    <oef:DistributionAndService12b1FeesOverAssets
      contextRef="Pid_S000007004_Cid_C000019124"
      decimals="6"
      id="ixv-101469"
      unitRef="pure">0.0025</oef:DistributionAndService12b1FeesOverAssets>
    <oef:DistributionAndService12b1FeesOverAssets
      contextRef="Pid_S000007004_Cid_C000019123"
      decimals="6"
      id="ixv-101470"
      unitRef="pure">0.0100</oef:DistributionAndService12b1FeesOverAssets>
    <oef:DistributionAndService12b1FeesOverAssets
      contextRef="Pid_S000007004_Cid_C000019125"
      decimals="6"
      id="ixv-101471"
      unitRef="pure">0</oef:DistributionAndService12b1FeesOverAssets>
    <oef:DistributionAndService12b1FeesOverAssets
      contextRef="Pid_S000007004_Cid_C000205019"
      decimals="6"
      id="ixv-101472"
      unitRef="pure">0</oef:DistributionAndService12b1FeesOverAssets>
    <oef:OtherExpensesOverAssets
      contextRef="Pid_S000007004_Cid_C000019121"
      decimals="6"
      id="ixv-101473"
      unitRef="pure">0.0022</oef:OtherExpensesOverAssets>
    <oef:OtherExpensesOverAssets
      contextRef="Pid_S000007004_Cid_C000019124"
      decimals="6"
      id="ixv-101474"
      unitRef="pure">0.0022</oef:OtherExpensesOverAssets>
    <oef:OtherExpensesOverAssets
      contextRef="Pid_S000007004_Cid_C000019123"
      decimals="6"
      id="ixv-101475"
      unitRef="pure">0.0024</oef:OtherExpensesOverAssets>
    <oef:OtherExpensesOverAssets
      contextRef="Pid_S000007004_Cid_C000019125"
      decimals="6"
      id="ixv-101476"
      unitRef="pure">0.0022</oef:OtherExpensesOverAssets>
    <oef:OtherExpensesOverAssets
      contextRef="Pid_S000007004_Cid_C000205019"
      decimals="6"
      id="ixv-101477"
      unitRef="pure">0.0012</oef:OtherExpensesOverAssets>
    <oef:ExpensesOverAssets
      contextRef="Pid_S000007004_Cid_C000019121"
      decimals="6"
      id="ixv-101478"
      unitRef="pure">0.0075</oef:ExpensesOverAssets>
    <oef:ExpensesOverAssets
      contextRef="Pid_S000007004_Cid_C000019124"
      decimals="6"
      id="ixv-101479"
      unitRef="pure">0.0075</oef:ExpensesOverAssets>
    <oef:ExpensesOverAssets
      contextRef="Pid_S000007004_Cid_C000019123"
      decimals="6"
      id="ixv-101480"
      unitRef="pure">0.0152</oef:ExpensesOverAssets>
    <oef:ExpensesOverAssets
      contextRef="Pid_S000007004_Cid_C000019125"
      decimals="6"
      id="ixv-101481"
      unitRef="pure">0.0050</oef:ExpensesOverAssets>
    <oef:ExpensesOverAssets
      contextRef="Pid_S000007004_Cid_C000205019"
      decimals="6"
      id="ixv-101482"
      unitRef="pure">0.0040</oef:ExpensesOverAssets>
    <oef:FeeWaiverOrReimbursementOverAssets
      contextRef="Pid_S000007004_Cid_C000019121"
      decimals="6"
      id="ixv-101483"
      unitRef="pure">-0.0000</oef:FeeWaiverOrReimbursementOverAssets>
    <oef:FeeWaiverOrReimbursementOverAssets
      contextRef="Pid_S000007004_Cid_C000019124"
      decimals="6"
      id="ixv-101484"
      unitRef="pure">-0.0000</oef:FeeWaiverOrReimbursementOverAssets>
    <oef:FeeWaiverOrReimbursementOverAssets
      contextRef="Pid_S000007004_Cid_C000019123"
      decimals="6"
      id="ixv-101485"
      unitRef="pure">-0.0000</oef:FeeWaiverOrReimbursementOverAssets>
    <oef:FeeWaiverOrReimbursementOverAssets
      contextRef="Pid_S000007004_Cid_C000019125"
      decimals="6"
      id="ixv-101486"
      unitRef="pure">-0.0000</oef:FeeWaiverOrReimbursementOverAssets>
    <oef:FeeWaiverOrReimbursementOverAssets
      contextRef="Pid_S000007004_Cid_C000205019"
      decimals="6"
      id="footnoteS000007004AIGB-PROAOE_AC000205019_FW"
      unitRef="pure">-0.0004</oef:FeeWaiverOrReimbursementOverAssets>
    <oef:NetExpensesOverAssets
      contextRef="Pid_S000007004_Cid_C000019121"
      decimals="6"
      id="ixv-101488"
      unitRef="pure">0.0075</oef:NetExpensesOverAssets>
    <oef:NetExpensesOverAssets
      contextRef="Pid_S000007004_Cid_C000019124"
      decimals="6"
      id="ixv-101489"
      unitRef="pure">0.0075</oef:NetExpensesOverAssets>
    <oef:NetExpensesOverAssets
      contextRef="Pid_S000007004_Cid_C000019123"
      decimals="6"
      id="ixv-101490"
      unitRef="pure">0.0152</oef:NetExpensesOverAssets>
    <oef:NetExpensesOverAssets
      contextRef="Pid_S000007004_Cid_C000019125"
      decimals="6"
      id="ixv-101491"
      unitRef="pure">0.0050</oef:NetExpensesOverAssets>
    <oef:NetExpensesOverAssets
      contextRef="Pid_S000007004_Cid_C000205019"
      decimals="6"
      id="ixv-101492"
      unitRef="pure">0.0036</oef:NetExpensesOverAssets>
    <oef:FeeWaiverOrReimbursementOverAssetsDateOfTermination
      contextRef="Pid_S000007004_contentCd_AIGB-PRO"
      id="ixv-16064">2026-12-31</oef:FeeWaiverOrReimbursementOverAssetsDateOfTermination>
    <oef:ExpenseExampleNarrativeTextBlock
      contextRef="Pid_S000007004_contentCd_AIGB-PRO"
      id="ixv-16073">


     This
     example

     helps compare the cost of investing in the fund with the cost of investing in other funds.

     Let's say, hypothetically, that the annual return for shares of the fund is 5% and that the fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated and if you hold your shares:

   </oef:ExpenseExampleNarrativeTextBlock>
    <oef:ExpenseExampleYear01
      contextRef="Pid_S000007004_Cid_C000019121"
      decimals="0"
      id="ixv-101493"
      unitRef="usd">474</oef:ExpenseExampleYear01>
    <oef:ExpenseExampleNoRedemptionYear01
      contextRef="Pid_S000007004_Cid_C000019121"
      decimals="0"
      id="ixv-101494"
      unitRef="usd">474</oef:ExpenseExampleNoRedemptionYear01>
    <oef:ExpenseExampleYear01
      contextRef="Pid_S000007004_Cid_C000019124"
      decimals="0"
      id="ixv-101495"
      unitRef="usd">474</oef:ExpenseExampleYear01>
    <oef:ExpenseExampleNoRedemptionYear01
      contextRef="Pid_S000007004_Cid_C000019124"
      decimals="0"
      id="ixv-101496"
      unitRef="usd">474</oef:ExpenseExampleNoRedemptionYear01>
    <oef:ExpenseExampleYear01
      contextRef="Pid_S000007004_Cid_C000019123"
      decimals="0"
      id="ixv-101497"
      unitRef="usd">255</oef:ExpenseExampleYear01>
    <oef:ExpenseExampleNoRedemptionYear01
      contextRef="Pid_S000007004_Cid_C000019123"
      decimals="0"
      id="ixv-101498"
      unitRef="usd">155</oef:ExpenseExampleNoRedemptionYear01>
    <oef:ExpenseExampleYear01
      contextRef="Pid_S000007004_Cid_C000019125"
      decimals="0"
      id="ixv-101499"
      unitRef="usd">51</oef:ExpenseExampleYear01>
    <oef:ExpenseExampleNoRedemptionYear01
      contextRef="Pid_S000007004_Cid_C000019125"
      decimals="0"
      id="ixv-101500"
      unitRef="usd">51</oef:ExpenseExampleNoRedemptionYear01>
    <oef:ExpenseExampleYear01
      contextRef="Pid_S000007004_Cid_C000205019"
      decimals="0"
      id="ixv-101501"
      unitRef="usd">37</oef:ExpenseExampleYear01>
    <oef:ExpenseExampleNoRedemptionYear01
      contextRef="Pid_S000007004_Cid_C000205019"
      decimals="0"
      id="ixv-101502"
      unitRef="usd">37</oef:ExpenseExampleNoRedemptionYear01>
    <oef:ExpenseExampleYear03
      contextRef="Pid_S000007004_Cid_C000019121"
      decimals="0"
      id="ixv-101503"
      unitRef="usd">630</oef:ExpenseExampleYear03>
    <oef:ExpenseExampleNoRedemptionYear03
      contextRef="Pid_S000007004_Cid_C000019121"
      decimals="0"
      id="ixv-101504"
      unitRef="usd">630</oef:ExpenseExampleNoRedemptionYear03>
    <oef:ExpenseExampleYear03
      contextRef="Pid_S000007004_Cid_C000019124"
      decimals="0"
      id="ixv-101505"
      unitRef="usd">630</oef:ExpenseExampleYear03>
    <oef:ExpenseExampleNoRedemptionYear03
      contextRef="Pid_S000007004_Cid_C000019124"
      decimals="0"
      id="ixv-101506"
      unitRef="usd">630</oef:ExpenseExampleNoRedemptionYear03>
    <oef:ExpenseExampleYear03
      contextRef="Pid_S000007004_Cid_C000019123"
      decimals="0"
      id="ixv-101507"
      unitRef="usd">480</oef:ExpenseExampleYear03>
    <oef:ExpenseExampleNoRedemptionYear03
      contextRef="Pid_S000007004_Cid_C000019123"
      decimals="0"
      id="ixv-101508"
      unitRef="usd">480</oef:ExpenseExampleNoRedemptionYear03>
    <oef:ExpenseExampleYear03
      contextRef="Pid_S000007004_Cid_C000019125"
      decimals="0"
      id="ixv-101509"
      unitRef="usd">160</oef:ExpenseExampleYear03>
    <oef:ExpenseExampleNoRedemptionYear03
      contextRef="Pid_S000007004_Cid_C000019125"
      decimals="0"
      id="ixv-101510"
      unitRef="usd">160</oef:ExpenseExampleNoRedemptionYear03>
    <oef:ExpenseExampleYear03
      contextRef="Pid_S000007004_Cid_C000205019"
      decimals="0"
      id="ixv-101511"
      unitRef="usd">123</oef:ExpenseExampleYear03>
    <oef:ExpenseExampleNoRedemptionYear03
      contextRef="Pid_S000007004_Cid_C000205019"
      decimals="0"
      id="ixv-101512"
      unitRef="usd">123</oef:ExpenseExampleNoRedemptionYear03>
    <oef:ExpenseExampleYear05
      contextRef="Pid_S000007004_Cid_C000019121"
      decimals="0"
      id="ixv-101513"
      unitRef="usd">800</oef:ExpenseExampleYear05>
    <oef:ExpenseExampleNoRedemptionYear05
      contextRef="Pid_S000007004_Cid_C000019121"
      decimals="0"
      id="ixv-101514"
      unitRef="usd">800</oef:ExpenseExampleNoRedemptionYear05>
    <oef:ExpenseExampleYear05
      contextRef="Pid_S000007004_Cid_C000019124"
      decimals="0"
      id="ixv-101515"
      unitRef="usd">800</oef:ExpenseExampleYear05>
    <oef:ExpenseExampleNoRedemptionYear05
      contextRef="Pid_S000007004_Cid_C000019124"
      decimals="0"
      id="ixv-101516"
      unitRef="usd">800</oef:ExpenseExampleNoRedemptionYear05>
    <oef:ExpenseExampleYear05
      contextRef="Pid_S000007004_Cid_C000019123"
      decimals="0"
      id="ixv-101517"
      unitRef="usd">829</oef:ExpenseExampleYear05>
    <oef:ExpenseExampleNoRedemptionYear05
      contextRef="Pid_S000007004_Cid_C000019123"
      decimals="0"
      id="ixv-101518"
      unitRef="usd">829</oef:ExpenseExampleNoRedemptionYear05>
    <oef:ExpenseExampleYear05
      contextRef="Pid_S000007004_Cid_C000019125"
      decimals="0"
      id="ixv-101519"
      unitRef="usd">280</oef:ExpenseExampleYear05>
    <oef:ExpenseExampleNoRedemptionYear05
      contextRef="Pid_S000007004_Cid_C000019125"
      decimals="0"
      id="ixv-101520"
      unitRef="usd">280</oef:ExpenseExampleNoRedemptionYear05>
    <oef:ExpenseExampleYear05
      contextRef="Pid_S000007004_Cid_C000205019"
      decimals="0"
      id="ixv-101521"
      unitRef="usd">219</oef:ExpenseExampleYear05>
    <oef:ExpenseExampleNoRedemptionYear05
      contextRef="Pid_S000007004_Cid_C000205019"
      decimals="0"
      id="ixv-101522"
      unitRef="usd">219</oef:ExpenseExampleNoRedemptionYear05>
    <oef:ExpenseExampleYear10
      contextRef="Pid_S000007004_Cid_C000019121"
      decimals="0"
      id="ixv-101523"
      unitRef="usd">1293</oef:ExpenseExampleYear10>
    <oef:ExpenseExampleNoRedemptionYear10
      contextRef="Pid_S000007004_Cid_C000019121"
      decimals="0"
      id="ixv-101524"
      unitRef="usd">1293</oef:ExpenseExampleNoRedemptionYear10>
    <oef:ExpenseExampleYear10
      contextRef="Pid_S000007004_Cid_C000019124"
      decimals="0"
      id="ixv-101525"
      unitRef="usd">1293</oef:ExpenseExampleYear10>
    <oef:ExpenseExampleNoRedemptionYear10
      contextRef="Pid_S000007004_Cid_C000019124"
      decimals="0"
      id="ixv-101526"
      unitRef="usd">1293</oef:ExpenseExampleNoRedemptionYear10>
    <oef:ExpenseExampleYear10
      contextRef="Pid_S000007004_Cid_C000019123"
      decimals="0"
      id="ixv-101527"
      unitRef="usd">1604</oef:ExpenseExampleYear10>
    <oef:ExpenseExampleNoRedemptionYear10
      contextRef="Pid_S000007004_Cid_C000019123"
      decimals="0"
      id="ixv-101528"
      unitRef="usd">1604</oef:ExpenseExampleNoRedemptionYear10>
    <oef:ExpenseExampleYear10
      contextRef="Pid_S000007004_Cid_C000019125"
      decimals="0"
      id="ixv-101529"
      unitRef="usd">628</oef:ExpenseExampleYear10>
    <oef:ExpenseExampleNoRedemptionYear10
      contextRef="Pid_S000007004_Cid_C000019125"
      decimals="0"
      id="ixv-101530"
      unitRef="usd">628</oef:ExpenseExampleNoRedemptionYear10>
    <oef:ExpenseExampleYear10
      contextRef="Pid_S000007004_Cid_C000205019"
      decimals="0"
      id="ixv-101531"
      unitRef="usd">500</oef:ExpenseExampleYear10>
    <oef:ExpenseExampleNoRedemptionYear10
      contextRef="Pid_S000007004_Cid_C000205019"
      decimals="0"
      id="ixv-101532"
      unitRef="usd">500</oef:ExpenseExampleNoRedemptionYear10>
    <oef:PortfolioTurnoverHeading
      contextRef="Pid_S000007004_contentCd_AIGB-PRO"
      id="ixv-16381">


     Portfolio Turnover


   </oef:PortfolioTurnoverHeading>
    <oef:PortfolioTurnoverTextBlock
      contextRef="Pid_S000007004_contentCd_AIGB-PRO"
      id="ixv-16386">


     The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was



       196


     % of the average value of its portfolio.


   </oef:PortfolioTurnoverTextBlock>
    <oef:PortfolioTurnoverRate
      contextRef="Pid_S000007004_contentCd_AIGB-PRO"
      decimals="4"
      id="ixv-101533"
      unitRef="pure">1.96</oef:PortfolioTurnoverRate>
    <oef:StrategyHeading
      contextRef="Pid_S000007004_contentCd_AIGB-PRO"
      id="ixv-16395">


     Principal Investment Strategies


   </oef:StrategyHeading>
    <oef:StrategyNarrativeTextBlock
      contextRef="Pid_S000007004_contentCd_AIGB-PRO"
      id="ixv-16400">




        Normally investing at least 80% of assets in investment-grade debt securities (those of medium and high quality) of all types and repurchase agreements for those securities.

     Debt securities are used by issuers to borrow money. The issuer usually pays a fixed, variable, or floating rate of interest, and must repay the amount borrowed, usually at the maturity of the security. Debt securities include corporate bonds, government securities (including Treasury securities), repurchase agreements, money market securities, mortgage and other asset-backed securities, loans and loan participations, and other securities, such as hybrids and synthetic securities, believed to have debt-like characteristics (e.g., securities classified as Tier 2 Regulatory capital, securities that rank above share capital in an insolvency waterfall, securities with maturity dates and non-cancellable interest payment structures).&#160;
     Investment grade securities in which the fund invests include securities or issuers rated at least BBB- or its equivalent by at least one nationally recognized statistical ratings organization (NRSRO), or, if unrated, determined by the Adviser to be of comparable quality.
     A repurchase agreement is an agreement to buy a security at one price and a simultaneous agreement to sell it back at an agreed-upon price.
     Effective December 11, 2025, derivative instruments that provide investment exposure to the investments above or exposure to one or more market risk factors associated with such investments are included in the fund's 80% policy, consistent with the fund's investment policies and limitations with respect to investments in derivatives.

      &#160;
      Managing the fund to have similar overall interest rate risk to the Bloomberg U.S. Aggregate Bond Index.
      Allocating assets across different market sectors and maturities.
      Investing in domestic and foreign issuers.
      Analyzing the credit quality of the issuer, security-specific features, current and potential future valuation, and trading opportunities to select investments.
      Investing in lower-quality debt securities (those of less than investment-grade quality, also referred to as high yield debt securities or junk bonds).
      Engaging in transactions that have a leveraging effect on the fund, including investments in derivatives - such as swaps (interest rate, total return, and credit default), options, and futures contracts - and forward-settling securities, to adjust the fund's risk exposure.
      Investing in Fidelity's Central funds (specialized investment vehicles used by Fidelity&#xae; funds to invest in particular security types or investment disciplines) consistent with the asset classes discussed above.


   </oef:StrategyNarrativeTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000007004_contentCd_AIGB-PRO_RiskMember_InterestRateChangesMember"
      id="ixv-16437">



      Interest Rate Changes.

     Interest rate increases can cause the price of a debt security to decrease.

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000007004_contentCd_AIGB-PRO_RiskMember_ForeignExposureMember"
      id="ixv-16446">



      Foreign Exposure.

     Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market.

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000007004_contentCd_AIGB-PRO_RiskMember_PrepaymentMember"
      id="ixv-16455">



      Prepayment.

     The ability of an issuer of a debt security to repay principal prior to a security's maturity can cause greater price volatility if interest rates change.

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000007004_contentCd_AIGB-PRO_RiskMember_IssuerSpecificChangesMember"
      id="ixv-16464">



      Issuer-Specific Changes.

     The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole.
     A decline in the credit quality of an issuer or a provider of credit support (such as guarantees) or a maturity-shortening structure (such as demand and put features) for a security can cause the price of a security to decrease.
     Lower-quality debt securities (those of less than investment-grade quality, also referred to as high yield debt securities or junk bonds) involve greater risk of default or price changes due to changes in the credit quality of the issuer. The value of lower-quality debt securities can be more volatile due to increased sensitivity to adverse issuer, political, regulatory, market, or economic developments.

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000007004_contentCd_AIGB-PRO_RiskMember_LeverageRiskMember"
      id="ixv-16481">



      Leverage Risk.

     Leverage can increase market exposure, magnify investment risks, and cause losses to be realized more quickly.

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000007004_contentCd_AIGB-PRO_RiskMember_HighPortfolioTurnoverMember"
      id="ixv-16490">



      High Portfolio Turnover.

     High portfolio turnover (more than 100%) may result in increased transaction costs and potentially higher capital gains or losses. The effects of higher than normal portfolio turnover may adversely affect the fund's performance.



   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000007004_contentCd_AIGB-PRO_RiskMember_RiskNotInsuredDepositoryInstitutionMember"
      id="ixv-16500">


     An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency

     .


   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000007004_contentCd_AIGB-PRO_RiskMember_RiskLoseMoneyMember"
      id="ixv-16508">


     &#160;

     You could lose money by investing in the fund.


   </oef:RiskTextBlock>
    <oef:BarChartAndPerformanceTableHeading
      contextRef="Pid_S000007004_contentCd_AIGB-PRO"
      id="ixv-16517">


     Performance


   </oef:BarChartAndPerformanceTableHeading>
    <oef:PerformanceNarrativeTextBlock
      contextRef="Pid_S000007004_contentCd_AIGB-PRO"
      id="ixv-16522">



       The following information is intended to help you understand the risks of investing in the fund.


      The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index over various periods of time.



     The index description appears in the "Additional Index Information" section of the prospectus.



      Past performance (before and after taxes) is not an indication of future performance.


     Visit



      institutional.fidelity.com


     for more recent performance information.

   </oef:PerformanceNarrativeTextBlock>
    <oef:PerformanceInformationIllustratesVariabilityOfReturns
      contextRef="Pid_S000007004_contentCd_AIGB-PRO"
      id="ixv-16528">

      The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index over various periods of time.

     </oef:PerformanceInformationIllustratesVariabilityOfReturns>
    <oef:PerformancePastDoesNotIndicateFuture
      contextRef="Pid_S000007004_contentCd_AIGB-PRO"
      id="ixv-16535">

      Past performance (before and after taxes) is not an indication of future performance.

     </oef:PerformancePastDoesNotIndicateFuture>
    <oef:PerformanceAvailabilityWebSiteAddress
      contextRef="Pid_S000007004_contentCd_AIGB-PRO"
      id="ixv-16541">

      institutional.fidelity.com
     </oef:PerformanceAvailabilityWebSiteAddress>
    <oef:BarChartHeading
      contextRef="Pid_S000007004_contentCd_AIGB-PRO"
      id="ixv-16546">


     Year-by-Year Returns

   </oef:BarChartHeading>
    <oef:BarChartNarrativeTextBlock
      contextRef="Pid_S000007004_contentCd_AIGB-PRO"
      id="ixv-16550">




      The returns in the bar chart do not reflect any applicable sales charges; if sales charges were reflected, returns would be lower than those shown.




   </oef:BarChartNarrativeTextBlock>
    <oef:BarChartDoesNotReflectSalesLoads
      contextRef="Pid_S000007004_contentCd_AIGB-PRO"
      id="ixv-16553">

      The returns in the bar chart do not reflect any applicable sales charges; if sales charges were reflected, returns would be lower than those shown.

     </oef:BarChartDoesNotReflectSalesLoads>
    <oef:AnnlRtrPct
      contextRef="Pid_S000007004_Cid_C000019121_2015"
      decimals="INF"
      id="ixv-101534"
      unitRef="pure">-0.0189</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000007004_Cid_C000019121_2016"
      decimals="INF"
      id="ixv-101535"
      unitRef="pure">0.0514</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000007004_Cid_C000019121_2017"
      decimals="INF"
      id="ixv-101536"
      unitRef="pure">0.0345</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000007004_Cid_C000019121_2018"
      decimals="INF"
      id="ixv-101537"
      unitRef="pure">-0.0055</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000007004_Cid_C000019121_2019"
      decimals="INF"
      id="ixv-101538"
      unitRef="pure">0.0933</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000007004_Cid_C000019121_2020"
      decimals="INF"
      id="ixv-101539"
      unitRef="pure">0.0958</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000007004_Cid_C000019121_2021"
      decimals="INF"
      id="ixv-101540"
      unitRef="pure">-0.0119</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000007004_Cid_C000019121_2022"
      decimals="INF"
      id="ixv-101541"
      unitRef="pure">-0.1364</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000007004_Cid_C000019121_2023"
      decimals="INF"
      id="ixv-101542"
      unitRef="pure">0.0616</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000007004_Cid_C000019121_2024"
      decimals="INF"
      id="ixv-101543"
      unitRef="pure">0.0128</oef:AnnlRtrPct>
    <oef:HighestQuarterlyReturnLabel
      contextRef="Pid_S000007004_contentCd_AIGB-PRO"
      id="ixv-16667">
          &#160;&#160;&#160;Highest Quarter Return
        </oef:HighestQuarterlyReturnLabel>
    <oef:BarChartHighestQuarterlyReturn
      contextRef="Pid_S000007004_contentCd_AIGB-PRO"
      decimals="4"
      id="ixv-101544"
      unitRef="pure">0.0681</oef:BarChartHighestQuarterlyReturn>
    <oef:BarChartHighestQuarterlyReturnDate
      contextRef="Pid_S000007004_contentCd_AIGB-PRO"
      id="ixv-16677">2023-12-31</oef:BarChartHighestQuarterlyReturnDate>
    <oef:LowestQuarterlyReturnLabel
      contextRef="Pid_S000007004_contentCd_AIGB-PRO"
      id="ixv-16682">
          &#160;&#160;&#160;Lowest Quarter Return
        </oef:LowestQuarterlyReturnLabel>
    <oef:BarChartLowestQuarterlyReturn
      contextRef="Pid_S000007004_contentCd_AIGB-PRO"
      decimals="4"
      id="ixv-101545"
      unitRef="pure">-0.0586</oef:BarChartLowestQuarterlyReturn>
    <oef:BarChartLowestQuarterlyReturnDate
      contextRef="Pid_S000007004_contentCd_AIGB-PRO"
      id="ixv-16693">2022-03-31</oef:BarChartLowestQuarterlyReturnDate>
    <oef:YearToDateReturnLabel
      contextRef="Pid_S000007004_contentCd_AIGB-PRO"
      id="ixv-16698">
          &#160;&#160;&#160;Year-to-Date Return
        </oef:YearToDateReturnLabel>
    <oef:BarChartYearToDateReturn
      contextRef="Pid_S000007004_contentCd_AIGB-PRO"
      decimals="4"
      id="ixv-101546"
      unitRef="pure">0.0606</oef:BarChartYearToDateReturn>
    <oef:BarChartYearToDateReturnDate
      contextRef="Pid_S000007004_contentCd_AIGB-PRO"
      id="ixv-16708">2025-09-30</oef:BarChartYearToDateReturnDate>
    <oef:PerformanceTableHeading
      contextRef="Pid_S000007004_contentCd_AIGB-PRO"
      id="ixv-16713">


     Average Annual Returns


   </oef:PerformanceTableHeading>
    <oef:PerformanceTableNarrativeTextBlock
      contextRef="Pid_S000007004_contentCd_AIGB-PRO"
      id="ixv-16719">




      Unlike the returns in the bar chart, the returns in the table reflect the maximum applicable sales charges.





      After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes.





      After-tax returns for Class A are shown in the table below and after-tax returns for other classes will vary.



     Actual after-tax returns may differ depending on your individual circumstances.


      The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan).




      Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.




   </oef:PerformanceTableNarrativeTextBlock>
    <oef:PerformanceTableDoesReflectSalesLoads
      contextRef="Pid_S000007004_contentCd_AIGB-PRO"
      id="ixv-16722">

      Unlike the returns in the bar chart, the returns in the table reflect the maximum applicable sales charges.

     </oef:PerformanceTableDoesReflectSalesLoads>
    <oef:PerformanceTableUsesHighestFederalRate
      contextRef="Pid_S000007004_contentCd_AIGB-PRO"
      id="ixv-16727">

      After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes.

     </oef:PerformanceTableUsesHighestFederalRate>
    <oef:PerformanceTableOneClassOfAfterTaxShown
      contextRef="Pid_S000007004_contentCd_AIGB-PRO"
      id="ixv-16732">

      After-tax returns for Class A are shown in the table below and after-tax returns for other classes will vary.

     </oef:PerformanceTableOneClassOfAfterTaxShown>
    <oef:PerformanceTableNotRelevantToTaxDeferred
      contextRef="Pid_S000007004_contentCd_AIGB-PRO"
      id="ixv-16738">

      The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan).
     </oef:PerformanceTableNotRelevantToTaxDeferred>
    <oef:PerformanceTableExplanationAfterTaxHigher
      contextRef="Pid_S000007004_contentCd_AIGB-PRO"
      id="ixv-16742">

      Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

     </oef:PerformanceTableExplanationAfterTaxHigher>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000007004_Cid_C000019121_ReturnBeforeTaxes_01"
      id="ixv-16773">
         Return Before Taxes
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007004_Cid_C000019121_ReturnBeforeTaxes_01"
      decimals="4"
      id="ixv-101547"
      unitRef="pure">-0.0277</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007004_Cid_C000019121_ReturnBeforeTaxes_05"
      decimals="4"
      id="ixv-101548"
      unitRef="pure">-0.0071</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007004_Cid_C000019121_ReturnBeforeTaxes_10"
      decimals="4"
      id="ixv-101549"
      unitRef="pure">0.0114</oef:AvgAnnlRtrPct>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000007004_Cid_C000019121_AfterTaxesOnDistributions_01"
      id="ixv-16792">
         Return After Taxes on Distributions
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007004_Cid_C000019121_AfterTaxesOnDistributions_01"
      decimals="4"
      id="ixv-101550"
      unitRef="pure">-0.0411</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007004_Cid_C000019121_AfterTaxesOnDistributions_05"
      decimals="4"
      id="ixv-101551"
      unitRef="pure">-0.0187</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007004_Cid_C000019121_AfterTaxesOnDistributions_10"
      decimals="4"
      id="ixv-101552"
      unitRef="pure">0.0006</oef:AvgAnnlRtrPct>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000007004_Cid_C000019121_AfterTaxesOnDistributionsAndSales_01"
      id="ixv-16810">
          Return After Taxes on Distributions and Sale of Fund Shares
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007004_Cid_C000019121_AfterTaxesOnDistributionsAndSales_01"
      decimals="4"
      id="ixv-101553"
      unitRef="pure">-0.0155</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007004_Cid_C000019121_AfterTaxesOnDistributionsAndSales_05"
      decimals="4"
      id="ixv-101554"
      unitRef="pure">-0.0098</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007004_Cid_C000019121_AfterTaxesOnDistributionsAndSales_10"
      decimals="4"
      id="ixv-101555"
      unitRef="pure">0.0042</oef:AvgAnnlRtrPct>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000007004_Cid_C000019124_ReturnBeforeTaxes_01"
      id="ixv-16827">
         Return Before Taxes
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007004_Cid_C000019124_ReturnBeforeTaxes_01"
      decimals="4"
      id="ixv-101556"
      unitRef="pure">-0.0276</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007004_Cid_C000019124_ReturnBeforeTaxes_05"
      decimals="4"
      id="ixv-101557"
      unitRef="pure">-0.0070</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007004_Cid_C000019124_ReturnBeforeTaxes_10"
      decimals="4"
      id="ixv-101558"
      unitRef="pure">0.0112</oef:AvgAnnlRtrPct>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000007004_Cid_C000019123_ReturnBeforeTaxes_01"
      id="ixv-16844">
         Return Before Taxes
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007004_Cid_C000019123_ReturnBeforeTaxes_01"
      decimals="4"
      id="ixv-101559"
      unitRef="pure">-0.0046</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007004_Cid_C000019123_ReturnBeforeTaxes_05"
      decimals="4"
      id="ixv-101560"
      unitRef="pure">-0.0066</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007004_Cid_C000019123_ReturnBeforeTaxes_10"
      decimals="4"
      id="ixv-101561"
      unitRef="pure">0.0093</oef:AvgAnnlRtrPct>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000007004_Cid_C000019125_ReturnBeforeTaxes_01"
      id="ixv-16861">
         Return Before Taxes
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007004_Cid_C000019125_ReturnBeforeTaxes_01"
      decimals="4"
      id="ixv-101562"
      unitRef="pure">0.0154</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007004_Cid_C000019125_ReturnBeforeTaxes_05"
      decimals="4"
      id="ixv-101563"
      unitRef="pure">0.0037</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007004_Cid_C000019125_ReturnBeforeTaxes_10"
      decimals="4"
      id="ixv-101564"
      unitRef="pure">0.0181</oef:AvgAnnlRtrPct>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000007004_Cid_C000205019_ReturnBeforeTaxes_01"
      id="ixv-16876">
         Return Before Taxes
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007004_Cid_C000205019_ReturnBeforeTaxes_01"
      decimals="4"
      id="ixv-101565"
      unitRef="pure">0.0169</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007004_Cid_C000205019_ReturnBeforeTaxes_05"
      decimals="4"
      id="ixv-101566"
      unitRef="pure">0.0051</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007004_Cid_C000205019_ReturnBeforeTaxes_AverageAnnualReturnSinceInception"
      decimals="4"
      id="footnoteAIGB-PROS000007004AAR_A_RBT_loc"
      unitRef="pure">0.0211</oef:AvgAnnlRtrPct>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000007004_Indexid_LB001_contentCd_AIGB-PRO_01"
      id="ixv-16891">
         Bloomberg U.S. Aggregate Bond Index
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007004_Indexid_LB001_contentCd_AIGB-PRO_01"
      decimals="4"
      id="ixv-101568"
      unitRef="pure">0.0125</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007004_Indexid_LB001_contentCd_AIGB-PRO_05"
      decimals="4"
      id="ixv-101569"
      unitRef="pure">-0.0033</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007004_Indexid_LB001_contentCd_AIGB-PRO_10"
      decimals="4"
      id="ixv-101570"
      unitRef="pure">0.0135</oef:AvgAnnlRtrPct>
    <oef:AnnualReturnInceptionDate contextRef="Pid_S000007004_Cid_C000205019" id="ixv-16933">2018-10-02</oef:AnnualReturnInceptionDate>
    <oef:RiskReturnHeading
      contextRef="Pid_S000017674_contentCd_IBF-PRO"
      id="ixv-23430">


     Fund Summary

     Fund:
     Fidelity&#xae; Intermediate Bond Fund

   </oef:RiskReturnHeading>
    <oef:ObjectiveHeading
      contextRef="Pid_S000017674_contentCd_IBF-PRO"
      id="ixv-23439">


     Investment Objective


   </oef:ObjectiveHeading>
    <oef:ObjectivePrimaryTextBlock
      contextRef="Pid_S000017674_contentCd_IBF-PRO"
      id="ixv-23444">


     Fidelity&#xae; Intermediate Bond Fund seeks a high level of current income.


   </oef:ObjectivePrimaryTextBlock>
    <oef:ExpenseHeading
      contextRef="Pid_S000017674_contentCd_IBF-PRO"
      id="ixv-23449">


     Fee Table


   </oef:ExpenseHeading>
    <oef:ExpenseNarrativeTextBlock
      contextRef="Pid_S000017674_contentCd_IBF-PRO"
      id="ixv-23455">


     The following table describes the fees and expenses that may be incurred when you buy, hold, and sell shares of the fund. You may pay other fees, such as brokerage commissions, which are not reflected in the tables and examples below.

   </oef:ExpenseNarrativeTextBlock>
    <oef:ShareholderFeesCaption
      contextRef="Pid_S000017674_contentCd_IBF-PRO"
      id="ixv-23466">


     Shareholder fees


   </oef:ShareholderFeesCaption>
    <oef:ShareholderFeeOther
      contextRef="Pid_S000017674_contentCd_IBF-PRO"
      decimals="0"
      id="ixv-101571"
      unitRef="usd">0</oef:ShareholderFeeOther>
    <oef:OperatingExpensesCaption
      contextRef="Pid_S000017674_contentCd_IBF-PRO"
      id="ixv-23481">


     Annual Operating Expenses


   </oef:OperatingExpensesCaption>
    <oef:ManagementFeesOverAssets
      contextRef="Pid_S000017674_Cid_C000048836"
      decimals="6"
      id="ixv-101572"
      unitRef="pure">0.0028</oef:ManagementFeesOverAssets>
    <oef:DistributionAndService12b1FeesOverAssets
      contextRef="Pid_S000017674_Cid_C000048836"
      decimals="6"
      id="ixv-101573"
      unitRef="pure">0</oef:DistributionAndService12b1FeesOverAssets>
    <oef:OtherExpensesOverAssets
      contextRef="Pid_S000017674_Cid_C000048836"
      decimals="6"
      id="ixv-101574"
      unitRef="pure">0.0017</oef:OtherExpensesOverAssets>
    <oef:ExpensesOverAssets
      contextRef="Pid_S000017674_Cid_C000048836"
      decimals="6"
      id="ixv-101575"
      unitRef="pure">0.0045</oef:ExpensesOverAssets>
    <oef:ExpenseExampleNarrativeTextBlock
      contextRef="Pid_S000017674_contentCd_IBF-PRO"
      id="ixv-23528">




     This
     example

     helps compare the cost of investing in the fund with the cost of investing in other funds.

     Let's say, hypothetically, that the annual return for shares of the fund is 5% and that the fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated:

   </oef:ExpenseExampleNarrativeTextBlock>
    <oef:ExpenseExampleYear01
      contextRef="Pid_S000017674_Cid_C000048836"
      decimals="0"
      id="ixv-101576"
      unitRef="usd">46</oef:ExpenseExampleYear01>
    <oef:ExpenseExampleYear03
      contextRef="Pid_S000017674_Cid_C000048836"
      decimals="0"
      id="ixv-101577"
      unitRef="usd">144</oef:ExpenseExampleYear03>
    <oef:ExpenseExampleYear05
      contextRef="Pid_S000017674_Cid_C000048836"
      decimals="0"
      id="ixv-101578"
      unitRef="usd">252</oef:ExpenseExampleYear05>
    <oef:ExpenseExampleYear10
      contextRef="Pid_S000017674_Cid_C000048836"
      decimals="0"
      id="ixv-101579"
      unitRef="usd">567</oef:ExpenseExampleYear10>
    <oef:PortfolioTurnoverHeading
      contextRef="Pid_S000017674_contentCd_IBF-PRO"
      id="ixv-23586">


     Portfolio Turnover


   </oef:PortfolioTurnoverHeading>
    <oef:PortfolioTurnoverTextBlock
      contextRef="Pid_S000017674_contentCd_IBF-PRO"
      id="ixv-23591">


     The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was



       33


     % of the average value of its portfolio.


   </oef:PortfolioTurnoverTextBlock>
    <oef:PortfolioTurnoverRate
      contextRef="Pid_S000017674_contentCd_IBF-PRO"
      decimals="4"
      id="ixv-101580"
      unitRef="pure">0.33</oef:PortfolioTurnoverRate>
    <oef:StrategyHeading
      contextRef="Pid_S000017674_contentCd_IBF-PRO"
      id="ixv-23600">


     Principal Investment Strategies


   </oef:StrategyHeading>
    <oef:StrategyNarrativeTextBlock
      contextRef="Pid_S000017674_contentCd_IBF-PRO"
      id="ixv-23605">




        Normally investing at least 80% of assets in investment-grade debt securities (those of medium and high quality) of all types and repurchase agreements for those securities.

     Debt securities are used by issuers to borrow money. The issuer usually pays a fixed, variable, or floating rate of interest, and must repay the amount borrowed, usually at the maturity of the security. Debt securities include corporate bonds, government securities (including Treasury securities), repurchase agreements, money market securities, mortgage and other asset-backed securities, loans and loan participations, and other securities, such as hybrids and synthetic securities, believed to have debt-like characteristics (e.g., securities classified as Tier 2 Regulatory capital, securities that rank above share capital in an insolvency waterfall, securities with maturity dates and non-cancellable interest payment structures).&#160;
     Investment grade securities in which the fund invests include securities or issuers rated at least BBB- or its equivalent by at least one nationally recognized statistical ratings organization (NRSRO), or, if unrated, determined by the Adviser to be of comparable quality.
     A repurchase agreement is an agreement to buy a security at one price and a simultaneous agreement to sell it back at an agreed-upon price.
     Effective December 11, 2025, derivative instruments that provide investment exposure to the investments above or exposure to one or more market risk factors associated with such investments are included in the fund's 80% policy, consistent with the fund's investment policies and limitations with respect to investments in derivatives.

      &#160;
      Managing the fund to have similar overall interest rate risk to the Bloomberg U.S. Intermediate Government/Credit Bond Index.
      Normally maintaining a dollar-weighted average maturity between three and 10 years.
      Allocating assets across different market sectors and maturities.
      Investing in domestic and foreign issuers.
      Analyzing the credit quality of the issuer, security-specific features, current and potential future valuation, and trading opportunities to select investments.
      Investing in lower-quality debt securities (those of less than investment-grade quality, also referred to as high yield debt securities or junk bonds).
      Engaging in transactions that have a leveraging effect on the fund, including investments in derivatives - such as swaps (interest rate, total return, and credit default), options, and futures contracts - and forward-settling securities, to adjust the fund's risk exposure.
      Investing in Fidelity's Central funds (specialized investment vehicles used by Fidelity&#xae; funds to invest in particular security types or investment disciplines) consistent with the asset classes discussed above.


   </oef:StrategyNarrativeTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000017674_contentCd_IBF-PRO_RiskMember_InterestRateChangesMember"
      id="ixv-23644">



      Interest Rate Changes.

     Interest rate increases can cause the price of a debt security to decrease.

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000017674_contentCd_IBF-PRO_RiskMember_ForeignExposureMember"
      id="ixv-23653">



      Foreign Exposure.

     Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market.

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000017674_contentCd_IBF-PRO_RiskMember_PrepaymentMember"
      id="ixv-23662">



      Prepayment.

     The ability of an issuer of a debt security to repay principal prior to a security's maturity can cause greater price volatility if interest rates change.

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000017674_contentCd_IBF-PRO_RiskMember_IssuerSpecificChangesMember"
      id="ixv-23671">



      Issuer-Specific Changes.

     The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole.
     A decline in the credit quality of an issuer or a provider of credit support (such as guarantees) or a maturity-shortening structure (such as demand and put features) for a security can cause the price of a security to decrease.
     Lower-quality debt securities (those of less than investment-grade quality, also referred to as high yield debt securities or junk bonds) involve greater risk of default or price changes due to changes in the credit quality of the issuer. The value of lower-quality debt securities can be more volatile due to increased sensitivity to adverse issuer, political, regulatory, market, or economic developments.

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000017674_contentCd_IBF-PRO_RiskMember_LeverageRiskMember"
      id="ixv-23688">



      Leverage Risk.

     Leverage can increase market exposure, magnify investment risks, and cause losses to be realized more quickly.



   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000017674_contentCd_IBF-PRO_RiskMember_RiskNotInsuredDepositoryInstitutionMember"
      id="ixv-23698">


     An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency

     .


   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000017674_contentCd_IBF-PRO_RiskMember_RiskLoseMoneyMember"
      id="ixv-23706">


     &#160;

     You could lose money by investing in the fund.


   </oef:RiskTextBlock>
    <oef:BarChartAndPerformanceTableHeading
      contextRef="Pid_S000017674_contentCd_IBF-PRO"
      id="ixv-23715">


     Performance


   </oef:BarChartAndPerformanceTableHeading>
    <oef:PerformanceNarrativeTextBlock
      contextRef="Pid_S000017674_contentCd_IBF-PRO"
      id="ixv-23720">



       The following information is intended to help you understand the risks of investing in the fund.


      The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time.



     The additional index has characteristics relevant to the fund's investment strategies. Index descriptions appear

     in the "Additional Index Information" section of the prospectus.



      Past performance (before and after taxes) is not an indication of future performance.


     Visit



      www.fidelity.com


     for more recent performance information.

   </oef:PerformanceNarrativeTextBlock>
    <oef:PerformanceInformationIllustratesVariabilityOfReturns
      contextRef="Pid_S000017674_contentCd_IBF-PRO"
      id="ixv-23726">

      The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time.

     </oef:PerformanceInformationIllustratesVariabilityOfReturns>
    <oef:PerformancePastDoesNotIndicateFuture
      contextRef="Pid_S000017674_contentCd_IBF-PRO"
      id="ixv-23735">

      Past performance (before and after taxes) is not an indication of future performance.

     </oef:PerformancePastDoesNotIndicateFuture>
    <oef:PerformanceAvailabilityWebSiteAddress
      contextRef="Pid_S000017674_contentCd_IBF-PRO"
      id="ixv-23741">

      www.fidelity.com
     </oef:PerformanceAvailabilityWebSiteAddress>
    <oef:BarChartHeading
      contextRef="Pid_S000017674_contentCd_IBF-PRO"
      id="ixv-23746">


     Year-by-Year Returns

   </oef:BarChartHeading>
    <oef:AnnlRtrPct
      contextRef="Pid_S000017674_Cid_C000048836_2015"
      decimals="INF"
      id="ixv-101581"
      unitRef="pure">0.0068</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000017674_Cid_C000048836_2016"
      decimals="INF"
      id="ixv-101582"
      unitRef="pure">0.0276</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000017674_Cid_C000048836_2017"
      decimals="INF"
      id="ixv-101583"
      unitRef="pure">0.0231</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000017674_Cid_C000048836_2018"
      decimals="INF"
      id="ixv-101584"
      unitRef="pure">0.0051</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000017674_Cid_C000048836_2019"
      decimals="INF"
      id="ixv-101585"
      unitRef="pure">0.0719</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000017674_Cid_C000048836_2020"
      decimals="INF"
      id="ixv-101586"
      unitRef="pure">0.0721</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000017674_Cid_C000048836_2021"
      decimals="INF"
      id="ixv-101587"
      unitRef="pure">-0.0133</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000017674_Cid_C000048836_2022"
      decimals="INF"
      id="ixv-101588"
      unitRef="pure">-0.0873</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000017674_Cid_C000048836_2023"
      decimals="INF"
      id="ixv-101589"
      unitRef="pure">0.0554</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000017674_Cid_C000048836_2024"
      decimals="INF"
      id="ixv-101590"
      unitRef="pure">0.0325</oef:AnnlRtrPct>
    <oef:HighestQuarterlyReturnLabel
      contextRef="Pid_S000017674_contentCd_IBF-PRO"
      id="ixv-23857">
          &#160;&#160;&#160;Highest Quarter Return
        </oef:HighestQuarterlyReturnLabel>
    <oef:BarChartHighestQuarterlyReturn
      contextRef="Pid_S000017674_contentCd_IBF-PRO"
      decimals="4"
      id="ixv-101591"
      unitRef="pure">0.0465</oef:BarChartHighestQuarterlyReturn>
    <oef:BarChartHighestQuarterlyReturnDate
      contextRef="Pid_S000017674_contentCd_IBF-PRO"
      id="ixv-23867">2020-06-30</oef:BarChartHighestQuarterlyReturnDate>
    <oef:LowestQuarterlyReturnLabel
      contextRef="Pid_S000017674_contentCd_IBF-PRO"
      id="ixv-23872">
          &#160;&#160;&#160;Lowest Quarter Return
        </oef:LowestQuarterlyReturnLabel>
    <oef:BarChartLowestQuarterlyReturn
      contextRef="Pid_S000017674_contentCd_IBF-PRO"
      decimals="4"
      id="ixv-101592"
      unitRef="pure">-0.0466</oef:BarChartLowestQuarterlyReturn>
    <oef:BarChartLowestQuarterlyReturnDate
      contextRef="Pid_S000017674_contentCd_IBF-PRO"
      id="ixv-23883">2022-03-31</oef:BarChartLowestQuarterlyReturnDate>
    <oef:YearToDateReturnLabel
      contextRef="Pid_S000017674_contentCd_IBF-PRO"
      id="ixv-23888">
          &#160;&#160;&#160;Year-to-Date Return
        </oef:YearToDateReturnLabel>
    <oef:BarChartYearToDateReturn
      contextRef="Pid_S000017674_contentCd_IBF-PRO"
      decimals="4"
      id="ixv-101593"
      unitRef="pure">0.0577</oef:BarChartYearToDateReturn>
    <oef:BarChartYearToDateReturnDate
      contextRef="Pid_S000017674_contentCd_IBF-PRO"
      id="ixv-23898">2025-09-30</oef:BarChartYearToDateReturnDate>
    <oef:PerformanceTableHeading
      contextRef="Pid_S000017674_contentCd_IBF-PRO"
      id="ixv-23903">


     Average Annual Returns


   </oef:PerformanceTableHeading>
    <oef:PerformanceTableNarrativeTextBlock
      contextRef="Pid_S000017674_contentCd_IBF-PRO"
      id="ixv-23908">




      After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes.



     Actual after-tax returns may differ depending on your individual circumstances.



      The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan).





      Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.




   </oef:PerformanceTableNarrativeTextBlock>
    <oef:PerformanceTableUsesHighestFederalRate
      contextRef="Pid_S000017674_contentCd_IBF-PRO"
      id="ixv-23911">

      After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes.

     </oef:PerformanceTableUsesHighestFederalRate>
    <oef:PerformanceTableNotRelevantToTaxDeferred
      contextRef="Pid_S000017674_contentCd_IBF-PRO"
      id="ixv-23918">

      The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan).

     </oef:PerformanceTableNotRelevantToTaxDeferred>
    <oef:PerformanceTableExplanationAfterTaxHigher
      contextRef="Pid_S000017674_contentCd_IBF-PRO"
      id="ixv-23923">

      Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

     </oef:PerformanceTableExplanationAfterTaxHigher>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000017674_Cid_C000048836_ReturnBeforeTaxes_01"
      id="ixv-23968">
         Return Before Taxes
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000017674_Cid_C000048836_ReturnBeforeTaxes_01"
      decimals="4"
      id="ixv-101594"
      unitRef="pure">0.0325</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000017674_Cid_C000048836_ReturnBeforeTaxes_05"
      decimals="4"
      id="ixv-101595"
      unitRef="pure">0.0102</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000017674_Cid_C000048836_ReturnBeforeTaxes_10"
      decimals="4"
      id="ixv-101596"
      unitRef="pure">0.0184</oef:AvgAnnlRtrPct>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000017674_Cid_C000048836_AfterTaxesOnDistributions_01"
      id="ixv-23983">
         Return After Taxes on Distributions
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000017674_Cid_C000048836_AfterTaxesOnDistributions_01"
      decimals="4"
      id="ixv-101597"
      unitRef="pure">0.0181</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000017674_Cid_C000048836_AfterTaxesOnDistributions_05"
      decimals="4"
      id="ixv-101598"
      unitRef="pure">-0.0011</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000017674_Cid_C000048836_AfterTaxesOnDistributions_10"
      decimals="4"
      id="ixv-101599"
      unitRef="pure">0.0076</oef:AvgAnnlRtrPct>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000017674_Cid_C000048836_AfterTaxesOnDistributionsAndSales_01"
      id="ixv-23999">
         Return After Taxes on Distributions and Sale of Fund Shares
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000017674_Cid_C000048836_AfterTaxesOnDistributionsAndSales_01"
      decimals="4"
      id="ixv-101600"
      unitRef="pure">0.0193</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000017674_Cid_C000048836_AfterTaxesOnDistributionsAndSales_05"
      decimals="4"
      id="ixv-101601"
      unitRef="pure">0.0034</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000017674_Cid_C000048836_AfterTaxesOnDistributionsAndSales_10"
      decimals="4"
      id="ixv-101602"
      unitRef="pure">0.0095</oef:AvgAnnlRtrPct>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000017674_Indexid_LB007_contentCd_IBF-PRO_01"
      id="ixv-24015">
         Bloomberg U.S. Intermediate Government/Credit Bond Index
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000017674_Indexid_LB007_contentCd_IBF-PRO_01"
      decimals="4"
      id="ixv-101603"
      unitRef="pure">0.0300</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000017674_Indexid_LB007_contentCd_IBF-PRO_05"
      decimals="4"
      id="ixv-101604"
      unitRef="pure">0.0086</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000017674_Indexid_LB007_contentCd_IBF-PRO_10"
      decimals="4"
      id="ixv-101605"
      unitRef="pure">0.0171</oef:AvgAnnlRtrPct>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000017674_Indexid_LB001_contentCd_IBF-PRO_01"
      id="ixv-24040">
         Bloomberg U.S. Aggregate Bond Index
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000017674_Indexid_LB001_contentCd_IBF-PRO_01"
      decimals="4"
      id="ixv-101606"
      unitRef="pure">0.0125</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000017674_Indexid_LB001_contentCd_IBF-PRO_05"
      decimals="4"
      id="ixv-101607"
      unitRef="pure">-0.0033</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000017674_Indexid_LB001_contentCd_IBF-PRO_10"
      decimals="4"
      id="ixv-101608"
      unitRef="pure">0.0135</oef:AvgAnnlRtrPct>
    <oef:RiskReturnHeading
      contextRef="Pid_S000062001_contentCd_ZCI-PRO"
      id="ixv-26134">


     Fund Summary

     Fund:
     Fidelity Flex&#xae; Conservative Income Bond Fund

   </oef:RiskReturnHeading>
    <oef:ObjectiveHeading
      contextRef="Pid_S000062001_contentCd_ZCI-PRO"
      id="ixv-26143">


     Investment Objective


   </oef:ObjectiveHeading>
    <oef:ObjectivePrimaryTextBlock
      contextRef="Pid_S000062001_contentCd_ZCI-PRO"
      id="ixv-26148">


     Fidelity Flex&#xae; Conservative Income Bond Fund seeks to obtain a high level of current income consistent with preservation of capital.


   </oef:ObjectivePrimaryTextBlock>
    <oef:ExpenseHeading
      contextRef="Pid_S000062001_contentCd_ZCI-PRO"
      id="ixv-26153">


     Fee Table


   </oef:ExpenseHeading>
    <oef:ExpenseNarrativeTextBlock
      contextRef="Pid_S000062001_contentCd_ZCI-PRO"
      id="ixv-26159">


     The following table describes the fees and expenses that may be incurred when you buy, hold, and sell shares of the fund. You may pay other fees, such as brokerage commissions, which are not reflected in the tables and examples below.

   </oef:ExpenseNarrativeTextBlock>
    <oef:ShareholderFeesCaption
      contextRef="Pid_S000062001_contentCd_ZCI-PRO"
      id="ixv-26170">


     Shareholder fees


   </oef:ShareholderFeesCaption>
    <oef:ShareholderFeeOther
      contextRef="Pid_S000062001_contentCd_ZCI-PRO"
      decimals="0"
      id="ixv-101609"
      unitRef="usd">0</oef:ShareholderFeeOther>
    <oef:OperatingExpensesCaption
      contextRef="Pid_S000062001_contentCd_ZCI-PRO"
      id="ixv-26185">


     Annual Operating Expenses


   </oef:OperatingExpensesCaption>
    <oef:ManagementFeesOverAssets
      contextRef="Pid_S000062001_Cid_C000200823"
      decimals="6"
      id="ixv-101610"
      unitRef="pure">0.0000</oef:ManagementFeesOverAssets>
    <oef:DistributionAndService12b1FeesOverAssets
      contextRef="Pid_S000062001_Cid_C000200823"
      decimals="6"
      id="ixv-101611"
      unitRef="pure">0</oef:DistributionAndService12b1FeesOverAssets>
    <oef:OtherExpensesOverAssets
      contextRef="Pid_S000062001_Cid_C000200823"
      decimals="6"
      id="ixv-101612"
      unitRef="pure">0.0000</oef:OtherExpensesOverAssets>
    <oef:ExpensesOverAssets
      contextRef="Pid_S000062001_Cid_C000200823"
      decimals="6"
      id="footnoteS000062001ZCI-PROAOE_AC000200823_TE"
      unitRef="pure">0.0000</oef:ExpensesOverAssets>
    <oef:ExpenseExampleNarrativeTextBlock
      contextRef="Pid_S000062001_contentCd_ZCI-PRO"
      id="ixv-26240">


     This
     example

     helps compare the cost of investing in the fund with the cost of investing in other funds.

     Let's say, hypothetically, that the annual return for shares of the fund is 5% and that the fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. This example does not include any fees paid at the fee-based account or plan level. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated:

   </oef:ExpenseExampleNarrativeTextBlock>
    <oef:ExpenseExampleYear01
      contextRef="Pid_S000062001_Cid_C000200823"
      decimals="0"
      id="ixv-101614"
      unitRef="usd">0</oef:ExpenseExampleYear01>
    <oef:ExpenseExampleYear03
      contextRef="Pid_S000062001_Cid_C000200823"
      decimals="0"
      id="ixv-101615"
      unitRef="usd">0</oef:ExpenseExampleYear03>
    <oef:ExpenseExampleYear05
      contextRef="Pid_S000062001_Cid_C000200823"
      decimals="0"
      id="ixv-101616"
      unitRef="usd">0</oef:ExpenseExampleYear05>
    <oef:ExpenseExampleYear10
      contextRef="Pid_S000062001_Cid_C000200823"
      decimals="0"
      id="ixv-101617"
      unitRef="usd">0</oef:ExpenseExampleYear10>
    <oef:PortfolioTurnoverHeading
      contextRef="Pid_S000062001_contentCd_ZCI-PRO"
      id="ixv-26297">


     Portfolio Turnover


   </oef:PortfolioTurnoverHeading>
    <oef:PortfolioTurnoverTextBlock
      contextRef="Pid_S000062001_contentCd_ZCI-PRO"
      id="ixv-26302">


     The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was



       71


     % of the average value of its portfolio.


   </oef:PortfolioTurnoverTextBlock>
    <oef:PortfolioTurnoverRate
      contextRef="Pid_S000062001_contentCd_ZCI-PRO"
      decimals="4"
      id="ixv-101618"
      unitRef="pure">0.71</oef:PortfolioTurnoverRate>
    <oef:StrategyHeading
      contextRef="Pid_S000062001_contentCd_ZCI-PRO"
      id="ixv-26311">


     Principal Investment Strategies


   </oef:StrategyHeading>
    <oef:StrategyNarrativeTextBlock
      contextRef="Pid_S000062001_contentCd_ZCI-PRO"
      id="ixv-26316">




        Normally investing at least 80% of assets in U.S. dollar-denominated money market and high quality investment-grade debt securities of all types, and repurchase agreements for those securities.

     Debt securities, including money market securities, are used by issuers to borrow money. The issuer usually pays a fixed, variable, or floating rate of interest, and must repay the amount borrowed, usually at the maturity of the security. Debt securities include corporate bonds, government securities (including Treasury securities), repurchase agreements, money market securities, and mortgage and other asset-backed securities. Money market securities include bank certificates of deposit, bankers' acceptances, bank time deposits, notes, commercial paper, and U.S. Government securities.
     High quality investment grade securities in which the fund invests include securities or issuers (i) rated at least A- or its equivalent by at least one nationally recognized statistical ratings organization (NRSRO) or similarly rated by the Adviser, and (ii) for securities with a credit maturity within one year, rated at least BBB or its equivalent by all NRSROs that rate the security and similarly rated by the Adviser.
     A repurchase agreement is an agreement to buy a security at one price and a simultaneous agreement to sell it back at an agreed-upon price.
     Effective December 11, 2025, derivative instruments that provide investment exposure to the investments above or exposure to one or more market risk factors associated with such investments are included in the fund's 80% policy, consistent with the fund's investment policies and limitations with respect to investments in derivatives.

      &#160;
      Potentially entering into reverse repurchase agreements.
      Managing the fund to have similar overall interest rate risk to the Bloomberg U.S. 3-6 Month Treasury Bill Index.
      Normally maintaining a dollar-weighted average maturity of one year or less.
      Normally investing in securities with a maximum maturity of four years.
      Allocating assets across different market sectors and maturities.
      Investing more than 25% of total assets in the financial services industries.
      Investing in domestic and foreign issuers.
      Analyzing the credit quality of the issuer, security-specific features, current and potential future valuation, and trading opportunities to select investments.


   </oef:StrategyNarrativeTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000062001_contentCd_ZCI-PRO_RiskMember_InterestRateChangesMember"
      id="ixv-26352">



      Interest Rate Changes.

     Interest rate increases can cause the price of a debt or money market security to decrease.

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000062001_contentCd_ZCI-PRO_RiskMember_ForeignExposureMember"
      id="ixv-26361">



      Foreign Exposure.

     Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market.

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000062001_contentCd_ZCI-PRO_RiskMember_FinancialServicesConcentrationMember"
      id="ixv-26370">



      Financial Services Concentration.

     Changes in government regulation and interest rates and economic downturns can have a significant negative effect on issuers in the financial services sector, including the price of their securities or their ability to meet their payment obligations.

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000062001_contentCd_ZCI-PRO_RiskMember_PrepaymentMember"
      id="ixv-26379">



      Prepayment.

     The ability of an issuer of a debt security to repay principal prior to a security's maturity can cause greater price volatility if interest rates change.

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000062001_contentCd_ZCI-PRO_RiskMember_IssuerSpecificChangesMember"
      id="ixv-26388">



      Issuer-Specific Changes.

     The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole.
     A decline in the credit quality of an issuer or a provider of credit support (such as guarantees) or a maturity-shortening structure (such as demand and put features) for a security can cause the price of a security to decrease.



   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000062001_contentCd_ZCI-PRO_RiskMember_RiskNotInsuredDepositoryInstitutionMember"
      id="ixv-26404">


     An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency

     .


   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000062001_contentCd_ZCI-PRO_RiskMember_RiskLoseMoneyMember"
      id="ixv-26412">


     &#160;

     You could lose money by investing in the fund.


   </oef:RiskTextBlock>
    <oef:BarChartAndPerformanceTableHeading
      contextRef="Pid_S000062001_contentCd_ZCI-PRO"
      id="ixv-26421">


     Performance


   </oef:BarChartAndPerformanceTableHeading>
    <oef:PerformanceNarrativeTextBlock
      contextRef="Pid_S000062001_contentCd_ZCI-PRO"
      id="ixv-26426">



       The following information is intended to help you understand the risks of investing in the fund.


      The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time.



     The additional index has characteristics relevant to the fund's investment strategies. Index descriptions appear

     in the "Additional Index Information" section of the prospectus.



      Past performance (before and after taxes) is not an indication of future performance.


     The performance shown does not reflect the impact of any fees paid at the fee-based account or plan level.
     Visit



      www.401k.com and log in or www.fidelity.com


     for more recent performance information.

   </oef:PerformanceNarrativeTextBlock>
    <oef:PerformanceInformationIllustratesVariabilityOfReturns
      contextRef="Pid_S000062001_contentCd_ZCI-PRO"
      id="ixv-26432">

      The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time.

     </oef:PerformanceInformationIllustratesVariabilityOfReturns>
    <oef:PerformancePastDoesNotIndicateFuture
      contextRef="Pid_S000062001_contentCd_ZCI-PRO"
      id="ixv-26441">

      Past performance (before and after taxes) is not an indication of future performance.

     </oef:PerformancePastDoesNotIndicateFuture>
    <oef:PerformanceAvailabilityWebSiteAddress
      contextRef="Pid_S000062001_contentCd_ZCI-PRO"
      id="ixv-26449">

      www.401k.com and log in or www.fidelity.com
     </oef:PerformanceAvailabilityWebSiteAddress>
    <oef:BarChartHeading
      contextRef="Pid_S000062001_contentCd_ZCI-PRO"
      id="ixv-26454">


     Year-by-Year Returns

   </oef:BarChartHeading>
    <oef:AnnlRtrPct
      contextRef="Pid_S000062001_Cid_C000200823_2019"
      decimals="INF"
      id="ixv-101619"
      unitRef="pure">0.0320</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000062001_Cid_C000200823_2020"
      decimals="INF"
      id="ixv-101620"
      unitRef="pure">0.0135</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000062001_Cid_C000200823_2021"
      decimals="INF"
      id="ixv-101621"
      unitRef="pure">0.0025</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000062001_Cid_C000200823_2022"
      decimals="INF"
      id="ixv-101622"
      unitRef="pure">0.0147</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000062001_Cid_C000200823_2023"
      decimals="INF"
      id="ixv-101623"
      unitRef="pure">0.0593</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000062001_Cid_C000200823_2024"
      decimals="INF"
      id="ixv-101624"
      unitRef="pure">0.0566</oef:AnnlRtrPct>
    <oef:HighestQuarterlyReturnLabel
      contextRef="Pid_S000062001_contentCd_ZCI-PRO"
      id="ixv-26551">
          &#160;&#160;&#160;Highest Quarter Return
        </oef:HighestQuarterlyReturnLabel>
    <oef:BarChartHighestQuarterlyReturn
      contextRef="Pid_S000062001_contentCd_ZCI-PRO"
      decimals="4"
      id="ixv-101625"
      unitRef="pure">0.0179</oef:BarChartHighestQuarterlyReturn>
    <oef:BarChartHighestQuarterlyReturnDate
      contextRef="Pid_S000062001_contentCd_ZCI-PRO"
      id="ixv-26561">2023-12-31</oef:BarChartHighestQuarterlyReturnDate>
    <oef:LowestQuarterlyReturnLabel
      contextRef="Pid_S000062001_contentCd_ZCI-PRO"
      id="ixv-26566">
          &#160;&#160;&#160;Lowest Quarter Return
        </oef:LowestQuarterlyReturnLabel>
    <oef:BarChartLowestQuarterlyReturn
      contextRef="Pid_S000062001_contentCd_ZCI-PRO"
      decimals="4"
      id="ixv-101626"
      unitRef="pure">-0.0079</oef:BarChartLowestQuarterlyReturn>
    <oef:BarChartLowestQuarterlyReturnDate
      contextRef="Pid_S000062001_contentCd_ZCI-PRO"
      id="ixv-26577">2020-03-31</oef:BarChartLowestQuarterlyReturnDate>
    <oef:YearToDateReturnLabel
      contextRef="Pid_S000062001_contentCd_ZCI-PRO"
      id="ixv-26582">
          &#160;&#160;&#160;Year-to-Date Return
        </oef:YearToDateReturnLabel>
    <oef:BarChartYearToDateReturn
      contextRef="Pid_S000062001_contentCd_ZCI-PRO"
      decimals="4"
      id="ixv-101627"
      unitRef="pure">0.0363</oef:BarChartYearToDateReturn>
    <oef:BarChartYearToDateReturnDate
      contextRef="Pid_S000062001_contentCd_ZCI-PRO"
      id="ixv-26592">2025-09-30</oef:BarChartYearToDateReturnDate>
    <oef:PerformanceTableHeading
      contextRef="Pid_S000062001_contentCd_ZCI-PRO"
      id="ixv-26597">


     Average Annual Returns


   </oef:PerformanceTableHeading>
    <oef:PerformanceTableNarrativeTextBlock
      contextRef="Pid_S000062001_contentCd_ZCI-PRO"
      id="ixv-26602">




      After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes.



     Actual after-tax returns may differ depending on your individual circumstances.



      The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan).





      Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.




   </oef:PerformanceTableNarrativeTextBlock>
    <oef:PerformanceTableUsesHighestFederalRate
      contextRef="Pid_S000062001_contentCd_ZCI-PRO"
      id="ixv-26605">

      After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes.

     </oef:PerformanceTableUsesHighestFederalRate>
    <oef:PerformanceTableNotRelevantToTaxDeferred
      contextRef="Pid_S000062001_contentCd_ZCI-PRO"
      id="ixv-26612">

      The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan).

     </oef:PerformanceTableNotRelevantToTaxDeferred>
    <oef:PerformanceTableExplanationAfterTaxHigher
      contextRef="Pid_S000062001_contentCd_ZCI-PRO"
      id="ixv-26617">

      Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

     </oef:PerformanceTableExplanationAfterTaxHigher>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000062001_Cid_C000200823_ReturnBeforeTaxes_01"
      id="ixv-26663">
         Return Before Taxes
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000062001_Cid_C000200823_ReturnBeforeTaxes_01"
      decimals="4"
      id="ixv-101628"
      unitRef="pure">0.0566</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000062001_Cid_C000200823_ReturnBeforeTaxes_05"
      decimals="4"
      id="ixv-101629"
      unitRef="pure">0.0290</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000062001_Cid_C000200823_ReturnBeforeTaxes_AverageAnnualReturnSinceInception"
      decimals="4"
      id="footnoteZCI-PROS000062001AAR_A_RBT_loc"
      unitRef="pure">0.0287</oef:AvgAnnlRtrPct>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000062001_Cid_C000200823_AfterTaxesOnDistributions_01"
      id="ixv-26679">
         Return After Taxes on Distributions
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000062001_Cid_C000200823_AfterTaxesOnDistributions_01"
      decimals="4"
      id="ixv-101631"
      unitRef="pure">0.0349</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000062001_Cid_C000200823_AfterTaxesOnDistributions_05"
      decimals="4"
      id="ixv-101632"
      unitRef="pure">0.0175</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000062001_Cid_C000200823_AfterTaxesOnDistributions_AverageAnnualReturnSinceInception"
      decimals="4"
      id="footnoteZCI-PROS000062001AAR_A_ATD_loc"
      unitRef="pure">0.0174</oef:AvgAnnlRtrPct>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000062001_Cid_C000200823_AfterTaxesOnDistributionsAndSales_01"
      id="ixv-26695">
         Return After Taxes on Distributions and Sale of Fund Shares
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000062001_Cid_C000200823_AfterTaxesOnDistributionsAndSales_01"
      decimals="4"
      id="ixv-101634"
      unitRef="pure">0.0345</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000062001_Cid_C000200823_AfterTaxesOnDistributionsAndSales_05"
      decimals="4"
      id="ixv-101635"
      unitRef="pure">0.0174</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000062001_Cid_C000200823_AfterTaxesOnDistributionsAndSales_AverageAnnualReturnSinceInception"
      decimals="4"
      id="footnoteZCI-PROS000062001AAR_A_ATDS_loc"
      unitRef="pure">0.0172</oef:AvgAnnlRtrPct>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000062001_Indexid_LB151_contentCd_ZCI-PRO_01"
      id="ixv-26712">
         Bloomberg U.S. 3-6 Month Treasury Bill Index
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000062001_Indexid_LB151_contentCd_ZCI-PRO_01"
      decimals="4"
      id="ixv-101637"
      unitRef="pure">0.0533</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000062001_Indexid_LB151_contentCd_ZCI-PRO_05"
      decimals="4"
      id="ixv-101638"
      unitRef="pure">0.0252</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000062001_Indexid_LB151_contentCd_ZCI-PRO_AverageAnnualReturnSinceInception"
      decimals="4"
      id="ixv-101639"
      unitRef="pure">0.0247</oef:AvgAnnlRtrPct>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000062001_Indexid_LB001_contentCd_ZCI-PRO_01"
      id="ixv-26737">
         Bloomberg U.S. Aggregate Bond Index
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000062001_Indexid_LB001_contentCd_ZCI-PRO_01"
      decimals="4"
      id="ixv-101640"
      unitRef="pure">0.0125</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000062001_Indexid_LB001_contentCd_ZCI-PRO_05"
      decimals="4"
      id="ixv-101641"
      unitRef="pure">-0.0033</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000062001_Indexid_LB001_contentCd_ZCI-PRO_AverageAnnualReturnSinceInception"
      decimals="4"
      id="ixv-101642"
      unitRef="pure">0.0126</oef:AvgAnnlRtrPct>
    <oef:AnnualReturnInceptionDate contextRef="Pid_S000062001_Cid_C000200823" id="ixv-26779">2018-05-31</oef:AnnualReturnInceptionDate>
    <oef:RiskReturnHeading
      contextRef="Pid_S000069440_contentCd_SST-LDI-PRO"
      id="ixv-28536">


     Fund Summary

     Fund:
     Fidelity&#xae; SAI Low Duration Bond Fund

   </oef:RiskReturnHeading>
    <oef:ObjectiveHeading
      contextRef="Pid_S000069440_contentCd_SST-LDI-PRO"
      id="ixv-28545">


     Investment Objective


   </oef:ObjectiveHeading>
    <oef:ObjectivePrimaryTextBlock
      contextRef="Pid_S000069440_contentCd_SST-LDI-PRO"
      id="ixv-28550">


     Fidelity&#xae; SAI Low Duration Bond

     Fund seeks to obtain a high level of current income consistent with preservation of capital.


   </oef:ObjectivePrimaryTextBlock>
    <oef:ExpenseHeading
      contextRef="Pid_S000069440_contentCd_SST-LDI-PRO"
      id="ixv-28557">


     Fee Table


   </oef:ExpenseHeading>
    <oef:ExpenseNarrativeTextBlock
      contextRef="Pid_S000069440_contentCd_SST-LDI-PRO"
      id="ixv-28563">


     The following table describes the fees and expenses that may be incurred when you buy, hold, and sell shares of the fund.

   </oef:ExpenseNarrativeTextBlock>
    <oef:ShareholderFeesCaption
      contextRef="Pid_S000069440_contentCd_SST-LDI-PRO"
      id="ixv-28573">


     Shareholder fees


   </oef:ShareholderFeesCaption>
    <oef:ShareholderFeeOther
      contextRef="Pid_S000069440_contentCd_SST-LDI-PRO"
      decimals="0"
      id="ixv-101643"
      unitRef="usd">0</oef:ShareholderFeeOther>
    <oef:OperatingExpensesCaption
      contextRef="Pid_S000069440_contentCd_SST-LDI-PRO"
      id="ixv-28588">


     Annual Operating Expenses


   </oef:OperatingExpensesCaption>
    <oef:ManagementFeesOverAssets
      contextRef="Pid_S000069440_Cid_C000221555"
      decimals="6"
      id="ixv-101644"
      unitRef="pure">0.0020</oef:ManagementFeesOverAssets>
    <oef:DistributionAndService12b1FeesOverAssets
      contextRef="Pid_S000069440_Cid_C000221555"
      decimals="6"
      id="ixv-101645"
      unitRef="pure">0</oef:DistributionAndService12b1FeesOverAssets>
    <oef:OtherExpensesOverAssets
      contextRef="Pid_S000069440_Cid_C000221555"
      decimals="6"
      id="ixv-101646"
      unitRef="pure">0.0001</oef:OtherExpensesOverAssets>
    <oef:ExpensesOverAssets
      contextRef="Pid_S000069440_Cid_C000221555"
      decimals="6"
      id="ixv-101647"
      unitRef="pure">0.0021</oef:ExpensesOverAssets>
    <oef:FeeWaiverOrReimbursementOverAssets
      contextRef="Pid_S000069440_Cid_C000221555"
      decimals="6"
      id="footnoteS000069440SST-LDI-PROAOE_AC000221555_FW"
      unitRef="pure">-0.0001</oef:FeeWaiverOrReimbursementOverAssets>
    <oef:NetExpensesOverAssets
      contextRef="Pid_S000069440_Cid_C000221555"
      decimals="6"
      id="ixv-101649"
      unitRef="pure">0.0020</oef:NetExpensesOverAssets>
    <oef:FeeWaiverOrReimbursementOverAssetsDateOfTermination
      contextRef="Pid_S000069440_contentCd_SST-LDI-PRO"
      id="ixv-28662">2026-12-31</oef:FeeWaiverOrReimbursementOverAssetsDateOfTermination>
    <oef:ExpenseExampleNarrativeTextBlock
      contextRef="Pid_S000069440_contentCd_SST-LDI-PRO"
      id="ixv-28671">


     This
     example

     helps compare the cost of investing in the fund with the cost of investing in other funds.

     Let's say, hypothetically, that the annual return for shares of the fund is 5% and that the fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated:

   </oef:ExpenseExampleNarrativeTextBlock>
    <oef:ExpenseExampleYear01
      contextRef="Pid_S000069440_Cid_C000221555"
      decimals="0"
      id="ixv-101650"
      unitRef="usd">20</oef:ExpenseExampleYear01>
    <oef:ExpenseExampleYear03
      contextRef="Pid_S000069440_Cid_C000221555"
      decimals="0"
      id="ixv-101651"
      unitRef="usd">66</oef:ExpenseExampleYear03>
    <oef:ExpenseExampleYear05
      contextRef="Pid_S000069440_Cid_C000221555"
      decimals="0"
      id="ixv-101652"
      unitRef="usd">117</oef:ExpenseExampleYear05>
    <oef:ExpenseExampleYear10
      contextRef="Pid_S000069440_Cid_C000221555"
      decimals="0"
      id="ixv-101653"
      unitRef="usd">266</oef:ExpenseExampleYear10>
    <oef:PortfolioTurnoverHeading
      contextRef="Pid_S000069440_contentCd_SST-LDI-PRO"
      id="ixv-28728">


     Portfolio Turnover


   </oef:PortfolioTurnoverHeading>
    <oef:PortfolioTurnoverTextBlock
      contextRef="Pid_S000069440_contentCd_SST-LDI-PRO"
      id="ixv-28733">


     The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was



       80


     % of the average value of its portfolio.


   </oef:PortfolioTurnoverTextBlock>
    <oef:PortfolioTurnoverRate
      contextRef="Pid_S000069440_contentCd_SST-LDI-PRO"
      decimals="4"
      id="ixv-101654"
      unitRef="pure">0.80</oef:PortfolioTurnoverRate>
    <oef:StrategyHeading
      contextRef="Pid_S000069440_contentCd_SST-LDI-PRO"
      id="ixv-28742">


     Principal Investment Strategies


   </oef:StrategyHeading>
    <oef:StrategyNarrativeTextBlock
      contextRef="Pid_S000069440_contentCd_SST-LDI-PRO"
      id="ixv-28747">




        Normally investing at least 80% of assets in investment-grade debt securities (those of medium and high quality) of all types and repurchase agreements for those securities.

     Debt securities are used by issuers to borrow money. The issuer usually pays a fixed, variable, or floating rate of interest, and must repay the amount borrowed, usually at the maturity of the security. Debt securities include corporate bonds, government securities (including Treasury securities), repurchase agreements, money market securities, mortgage and other asset-backed securities, loans and loan participations, and other securities, such as hybrids and synthetic securities, believed to have debt-like characteristics (e.g., securities classified as Tier 2 Regulatory capital, securities that rank above share capital in an insolvency waterfall, securities with maturity dates and non-cancellable interest payment structures).&#160;
     Investment grade securities in which the fund invests include securities or issuers rated at least BBB- or its equivalent by at least one nationally recognized statistical ratings organization (NRSRO), or, if unrated, determined by the Adviser to be of comparable quality.
     A repurchase agreement is an agreement to buy a security at one price and a simultaneous agreement to sell it back at an agreed-upon price.
     Effective December 11, 2025, derivative instruments that provide investment exposure to the investments above or exposure to one or more market risk factors associated with such investments are included in the fund's 80% policy, consistent with the fund's investment policies and limitations with respect to investments in derivatives.

      &#160;
      Normally maintaining a duration of 1 year or less.
      Managing the fund to have similar overall interest rate risk to the Bloomberg US Treasury Bill: 6-9 Months Index.
      Normally maintaining a dollar-weighted average maturity of two years or less.
      Allocating assets across different market sectors and maturities.
      Investing more than 25% of total assets in the financial services industries.
      Investing in domestic and foreign issuers.
      Analyzing the credit quality of the issuer, security-specific features, current and potential future valuation, and trading opportunities to select investments.
      Engaging in transactions that have a leveraging effect on the fund, including investments in derivatives - such as swaps (interest rate, total return, and credit default), options, and futures contracts - and forward-settling securities, to adjust the fund's risk exposure.


   </oef:StrategyNarrativeTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000069440_contentCd_SST-LDI-PRO_RiskMember_InterestRateChangesMember"
      id="ixv-28784">



      Interest Rate Changes.

     Interest rate increases can cause the price of a debt security to decrease.

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000069440_contentCd_SST-LDI-PRO_RiskMember_ForeignExposureMember"
      id="ixv-28793">



      Foreign Exposure.

     Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market.

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000069440_contentCd_SST-LDI-PRO_RiskMember_FinancialServicesConcentrationMember"
      id="ixv-28802">



      Financial Services Concentration.

     Changes in government regulation and interest rates and economic downturns can have a significant negative effect on issuers in the financial services sector, including the price of their securities or their ability to meet their payment obligations.

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000069440_contentCd_SST-LDI-PRO_RiskMember_PrepaymentMember"
      id="ixv-28811">



      Prepayment.

     The ability of an issuer of a debt security to repay principal prior to a security's maturity can cause greater price volatility if interest rates change.

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000069440_contentCd_SST-LDI-PRO_RiskMember_IssuerSpecificChangesMember"
      id="ixv-28820">



      Issuer-Specific Changes.

     The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole.
     A decline in the credit quality of an issuer or a provider of credit support (such as guarantees) or a maturity-shortening structure (such as demand and put features) for a security can cause the price of a security to decrease.

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000069440_contentCd_SST-LDI-PRO_RiskMember_LeverageRiskMember"
      id="ixv-28835">



      Leverage Risk.

     Leverage can increase market exposure, magnify investment risks, and cause losses to be realized more quickly.



   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000069440_contentCd_SST-LDI-PRO_RiskMember_RiskNotInsuredDepositoryInstitutionMember"
      id="ixv-28845">


     An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency

     .


   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000069440_contentCd_SST-LDI-PRO_RiskMember_RiskLoseMoneyMember"
      id="ixv-28853">


     &#160;

     You could lose money by investing in the fund.


   </oef:RiskTextBlock>
    <oef:BarChartAndPerformanceTableHeading
      contextRef="Pid_S000069440_contentCd_SST-LDI-PRO"
      id="ixv-28862">


     Performance


   </oef:BarChartAndPerformanceTableHeading>
    <oef:PerformanceNarrativeTextBlock
      contextRef="Pid_S000069440_contentCd_SST-LDI-PRO"
      id="ixv-28867">



       The following information is intended to help you understand the risks of investing in the fund.


      The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time.



     The additional index has characteristics relevant to the fund's investment strategies. Index descriptions appear

     in the "Additional Index Information" section of the prospectus.



      Past performance (before and after taxes) is not an indication of future performance.


     Visit



      www.fidelity.com


     for more recent performance information.

   </oef:PerformanceNarrativeTextBlock>
    <oef:PerformanceInformationIllustratesVariabilityOfReturns
      contextRef="Pid_S000069440_contentCd_SST-LDI-PRO"
      id="ixv-28873">

      The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time.

     </oef:PerformanceInformationIllustratesVariabilityOfReturns>
    <oef:PerformancePastDoesNotIndicateFuture
      contextRef="Pid_S000069440_contentCd_SST-LDI-PRO"
      id="ixv-28882">

      Past performance (before and after taxes) is not an indication of future performance.

     </oef:PerformancePastDoesNotIndicateFuture>
    <oef:PerformanceAvailabilityWebSiteAddress
      contextRef="Pid_S000069440_contentCd_SST-LDI-PRO"
      id="ixv-28888">

      www.fidelity.com
     </oef:PerformanceAvailabilityWebSiteAddress>
    <oef:BarChartHeading
      contextRef="Pid_S000069440_contentCd_SST-LDI-PRO"
      id="ixv-28893">


     Year-by-Year Returns

   </oef:BarChartHeading>
    <oef:AnnlRtrPct
      contextRef="Pid_S000069440_Cid_C000221555_2021"
      decimals="INF"
      id="ixv-101655"
      unitRef="pure">-0.0001</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000069440_Cid_C000221555_2022"
      decimals="INF"
      id="ixv-101656"
      unitRef="pure">0.0073</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000069440_Cid_C000221555_2023"
      decimals="INF"
      id="ixv-101657"
      unitRef="pure">0.0570</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000069440_Cid_C000221555_2024"
      decimals="INF"
      id="ixv-101658"
      unitRef="pure">0.0556</oef:AnnlRtrPct>
    <oef:HighestQuarterlyReturnLabel
      contextRef="Pid_S000069440_contentCd_SST-LDI-PRO"
      id="ixv-28985">
          &#160;&#160;&#160;Highest Quarter Return
        </oef:HighestQuarterlyReturnLabel>
    <oef:BarChartHighestQuarterlyReturn
      contextRef="Pid_S000069440_contentCd_SST-LDI-PRO"
      decimals="4"
      id="ixv-101659"
      unitRef="pure">0.0183</oef:BarChartHighestQuarterlyReturn>
    <oef:BarChartHighestQuarterlyReturnDate
      contextRef="Pid_S000069440_contentCd_SST-LDI-PRO"
      id="ixv-28995">2024-09-30</oef:BarChartHighestQuarterlyReturnDate>
    <oef:LowestQuarterlyReturnLabel
      contextRef="Pid_S000069440_contentCd_SST-LDI-PRO"
      id="ixv-29000">
          &#160;&#160;&#160;Lowest Quarter Return
        </oef:LowestQuarterlyReturnLabel>
    <oef:BarChartLowestQuarterlyReturn
      contextRef="Pid_S000069440_contentCd_SST-LDI-PRO"
      decimals="4"
      id="ixv-101660"
      unitRef="pure">-0.0053</oef:BarChartLowestQuarterlyReturn>
    <oef:BarChartLowestQuarterlyReturnDate
      contextRef="Pid_S000069440_contentCd_SST-LDI-PRO"
      id="ixv-29011">2022-03-31</oef:BarChartLowestQuarterlyReturnDate>
    <oef:YearToDateReturnLabel
      contextRef="Pid_S000069440_contentCd_SST-LDI-PRO"
      id="ixv-29016">
          &#160;&#160;&#160;Year-to-Date Return
        </oef:YearToDateReturnLabel>
    <oef:BarChartYearToDateReturn
      contextRef="Pid_S000069440_contentCd_SST-LDI-PRO"
      decimals="4"
      id="ixv-101661"
      unitRef="pure">0.0361</oef:BarChartYearToDateReturn>
    <oef:BarChartYearToDateReturnDate
      contextRef="Pid_S000069440_contentCd_SST-LDI-PRO"
      id="ixv-29026">2025-09-30</oef:BarChartYearToDateReturnDate>
    <oef:PerformanceTableHeading
      contextRef="Pid_S000069440_contentCd_SST-LDI-PRO"
      id="ixv-29031">


     Average Annual Returns


   </oef:PerformanceTableHeading>
    <oef:PerformanceTableNarrativeTextBlock
      contextRef="Pid_S000069440_contentCd_SST-LDI-PRO"
      id="ixv-29036">




      After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes.



     Actual after-tax returns may differ depending on your individual circumstances.



      The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan).





      Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.




   </oef:PerformanceTableNarrativeTextBlock>
    <oef:PerformanceTableUsesHighestFederalRate
      contextRef="Pid_S000069440_contentCd_SST-LDI-PRO"
      id="ixv-29039">

      After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes.

     </oef:PerformanceTableUsesHighestFederalRate>
    <oef:PerformanceTableNotRelevantToTaxDeferred
      contextRef="Pid_S000069440_contentCd_SST-LDI-PRO"
      id="ixv-29046">

      The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan).

     </oef:PerformanceTableNotRelevantToTaxDeferred>
    <oef:PerformanceTableExplanationAfterTaxHigher
      contextRef="Pid_S000069440_contentCd_SST-LDI-PRO"
      id="ixv-29051">

      Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

     </oef:PerformanceTableExplanationAfterTaxHigher>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000069440_Cid_C000221555_ReturnBeforeTaxes_01"
      id="ixv-29089">
         Return Before Taxes
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000069440_Cid_C000221555_ReturnBeforeTaxes_01"
      decimals="4"
      id="ixv-101662"
      unitRef="pure">0.0556</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000069440_Cid_C000221555_ReturnBeforeTaxes_AverageAnnualReturnSinceInception"
      decimals="4"
      id="footnoteSST-LDI-PROS000069440AAR_A_RBT_loc"
      unitRef="pure">0.0279</oef:AvgAnnlRtrPct>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000069440_Cid_C000221555_AfterTaxesOnDistributions_01"
      id="ixv-29102">
         Return After Taxes on Distributions
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000069440_Cid_C000221555_AfterTaxesOnDistributions_01"
      decimals="4"
      id="ixv-101664"
      unitRef="pure">0.0345</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000069440_Cid_C000221555_AfterTaxesOnDistributions_AverageAnnualReturnSinceInception"
      decimals="4"
      id="footnoteSST-LDI-PROS000069440AAR_A_ATD_loc"
      unitRef="pure">0.0174</oef:AvgAnnlRtrPct>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000069440_Cid_C000221555_AfterTaxesOnDistributionsAndSales_01"
      id="ixv-29115">
         Return After Taxes on Distributions and Sale of Fund Shares
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000069440_Cid_C000221555_AfterTaxesOnDistributionsAndSales_01"
      decimals="4"
      id="ixv-101666"
      unitRef="pure">0.0333</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000069440_Cid_C000221555_AfterTaxesOnDistributionsAndSales_AverageAnnualReturnSinceInception"
      decimals="4"
      id="footnoteSST-LDI-PROS000069440AAR_A_ATDS_loc"
      unitRef="pure">0.0169</oef:AvgAnnlRtrPct>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000069440_Indexid_IXXXY_contentCd_SST-LDI-PRO_01"
      id="ixv-29129">
         Bloomberg US Treasury Bill: 6-9 Months Index
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000069440_Indexid_IXXXY_contentCd_SST-LDI-PRO_01"
      decimals="4"
      id="ixv-101668"
      unitRef="pure">0.0488</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000069440_Indexid_IXXXY_contentCd_SST-LDI-PRO_AverageAnnualReturnSinceInception"
      decimals="4"
      id="ixv-101669"
      unitRef="pure">0.0224</oef:AvgAnnlRtrPct>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000069440_Indexid_LB001_contentCd_SST-LDI-PRO_01"
      id="ixv-29148">
         Bloomberg U.S. Aggregate Bond Index
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000069440_Indexid_LB001_contentCd_SST-LDI-PRO_01"
      decimals="4"
      id="ixv-101670"
      unitRef="pure">0.0125</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000069440_Indexid_LB001_contentCd_SST-LDI-PRO_AverageAnnualReturnSinceInception"
      decimals="4"
      id="ixv-101671"
      unitRef="pure">-0.0194</oef:AvgAnnlRtrPct>
    <oef:AnnualReturnInceptionDate contextRef="Pid_S000069440_Cid_C000221555" id="ixv-29181">2020-09-15</oef:AnnualReturnInceptionDate>
    <oef:RiskReturnHeading
      contextRef="Pid_S000069441_contentCd_SST-LDI-PRO"
      id="ixv-29227">


     Fund Summary

     Fund:
     Fidelity&#xae; SAI Short-Term Bond Fund

   </oef:RiskReturnHeading>
    <oef:ObjectiveHeading
      contextRef="Pid_S000069441_contentCd_SST-LDI-PRO"
      id="ixv-29236">


     Investment Objective


   </oef:ObjectiveHeading>
    <oef:ObjectivePrimaryTextBlock
      contextRef="Pid_S000069441_contentCd_SST-LDI-PRO"
      id="ixv-29241">


     Fidelity&#xae; SAI Short-Term Bond Fund seeks to obtain a high level of current income consistent with preservation of capital.


   </oef:ObjectivePrimaryTextBlock>
    <oef:ExpenseHeading
      contextRef="Pid_S000069441_contentCd_SST-LDI-PRO"
      id="ixv-29246">


     Fee Table


   </oef:ExpenseHeading>
    <oef:ExpenseNarrativeTextBlock
      contextRef="Pid_S000069441_contentCd_SST-LDI-PRO"
      id="ixv-29252">


     The following table describes the fees and expenses that may be incurred when you buy, hold, and sell shares of the fund.

   </oef:ExpenseNarrativeTextBlock>
    <oef:ShareholderFeesCaption
      contextRef="Pid_S000069441_contentCd_SST-LDI-PRO"
      id="ixv-29262">


     Shareholder fees


   </oef:ShareholderFeesCaption>
    <oef:ShareholderFeeOther
      contextRef="Pid_S000069441_contentCd_SST-LDI-PRO"
      decimals="0"
      id="ixv-101672"
      unitRef="usd">0</oef:ShareholderFeeOther>
    <oef:OperatingExpensesCaption
      contextRef="Pid_S000069441_contentCd_SST-LDI-PRO"
      id="ixv-29277">


     Annual Operating Expenses


   </oef:OperatingExpensesCaption>
    <oef:ManagementFeesOverAssets
      contextRef="Pid_S000069441_Cid_C000221556"
      decimals="6"
      id="ixv-101673"
      unitRef="pure">0.0020</oef:ManagementFeesOverAssets>
    <oef:DistributionAndService12b1FeesOverAssets
      contextRef="Pid_S000069441_Cid_C000221556"
      decimals="6"
      id="ixv-101674"
      unitRef="pure">0</oef:DistributionAndService12b1FeesOverAssets>
    <oef:OtherExpensesOverAssets
      contextRef="Pid_S000069441_Cid_C000221556"
      decimals="6"
      id="ixv-101675"
      unitRef="pure">0.0001</oef:OtherExpensesOverAssets>
    <oef:ExpensesOverAssets
      contextRef="Pid_S000069441_Cid_C000221556"
      decimals="6"
      id="ixv-101676"
      unitRef="pure">0.0021</oef:ExpensesOverAssets>
    <oef:ExpenseExampleNarrativeTextBlock
      contextRef="Pid_S000069441_contentCd_SST-LDI-PRO"
      id="ixv-29324">


     This
     example

     helps compare the cost of investing in the fund with the cost of investing in other funds.

     Let's say, hypothetically, that the annual return for shares of the fund is 5% and that the fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated:

   </oef:ExpenseExampleNarrativeTextBlock>
    <oef:ExpenseExampleYear01
      contextRef="Pid_S000069441_Cid_C000221556"
      decimals="0"
      id="ixv-101677"
      unitRef="usd">22</oef:ExpenseExampleYear01>
    <oef:ExpenseExampleYear03
      contextRef="Pid_S000069441_Cid_C000221556"
      decimals="0"
      id="ixv-101678"
      unitRef="usd">68</oef:ExpenseExampleYear03>
    <oef:ExpenseExampleYear05
      contextRef="Pid_S000069441_Cid_C000221556"
      decimals="0"
      id="ixv-101679"
      unitRef="usd">118</oef:ExpenseExampleYear05>
    <oef:ExpenseExampleYear10
      contextRef="Pid_S000069441_Cid_C000221556"
      decimals="0"
      id="ixv-101680"
      unitRef="usd">268</oef:ExpenseExampleYear10>
    <oef:PortfolioTurnoverHeading
      contextRef="Pid_S000069441_contentCd_SST-LDI-PRO"
      id="ixv-29381">


     Portfolio Turnover


   </oef:PortfolioTurnoverHeading>
    <oef:PortfolioTurnoverTextBlock
      contextRef="Pid_S000069441_contentCd_SST-LDI-PRO"
      id="ixv-29386">


     The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was



       87


     % of the average value of its portfolio.


   </oef:PortfolioTurnoverTextBlock>
    <oef:PortfolioTurnoverRate
      contextRef="Pid_S000069441_contentCd_SST-LDI-PRO"
      decimals="4"
      id="ixv-101681"
      unitRef="pure">0.87</oef:PortfolioTurnoverRate>
    <oef:StrategyHeading
      contextRef="Pid_S000069441_contentCd_SST-LDI-PRO"
      id="ixv-29395">


     Principal Investment Strategies


   </oef:StrategyHeading>
    <oef:StrategyNarrativeTextBlock
      contextRef="Pid_S000069441_contentCd_SST-LDI-PRO"
      id="ixv-29400">




        Normally investing at least 80% of assets in investment-grade debt securities (those of medium and high quality) of all types and repurchase agreements for those securities.

     Debt securities are used by issuers to borrow money. The issuer usually pays a fixed, variable, or floating rate of interest, and must repay the amount borrowed, usually at the maturity of the security. Debt securities include corporate bonds, government securities (including Treasury securities), repurchase agreements, money market securities, mortgage and other asset-backed securities, loans and loan participations, and other securities, such as hybrids and synthetic securities, believed to have debt-like characteristics (e.g., securities classified as Tier 2 Regulatory capital, securities that rank above share capital in an insolvency waterfall, securities with maturity dates and non-cancellable interest payment structures).&#160;
     Investment grade securities in which the fund invests include securities or issuers rated at least BBB- or its equivalent by at least one nationally recognized statistical ratings organization (NRSRO), or, if unrated, determined by the Adviser to be of comparable quality.
     A repurchase agreement is an agreement to buy a security at one price and a simultaneous agreement to sell it back at an agreed-upon price.
     Effective December 11, 2025, derivative instruments that provide investment exposure to the investments above or exposure to one or more market risk factors associated with such investments are included in the fund's 80% policy, consistent with the fund's investment policies and limitations with respect to investments in derivatives.

      &#160;
      Managing the fund to have similar overall interest rate risk to the Bloomberg U.S. 1-3 Year Government/Credit Bond Index.
      Normally maintaining a dollar-weighted average maturity of three years or less.
      Allocating assets across different market sectors and maturities.
      Investing in domestic and foreign issuers.
      Analyzing the credit quality of the issuer, security-specific features, current and potential future valuation, and trading opportunities to select investments.
      Engaging in transactions that have a leveraging effect on the fund, including investments in derivatives - such as swaps (interest rate, total return, and credit default), options, and futures contracts - and forward-settling securities, to adjust the fund's risk exposure.


   </oef:StrategyNarrativeTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000069441_contentCd_SST-LDI-PRO_RiskMember_InterestRateChangesMember"
      id="ixv-29433">



      Interest Rate Changes.

     Interest rate increases can cause the price of a debt security to decrease.

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000069441_contentCd_SST-LDI-PRO_RiskMember_ForeignExposureMember"
      id="ixv-29442">



      Foreign Exposure.

     Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market.

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000069441_contentCd_SST-LDI-PRO_RiskMember_PrepaymentMember"
      id="ixv-29451">



      Prepayment.

     The ability of an issuer of a debt security to repay principal prior to a security's maturity can cause greater price volatility if interest rates change.

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000069441_contentCd_SST-LDI-PRO_RiskMember_IssuerSpecificChangesMember"
      id="ixv-29460">



      Issuer-Specific Changes.

     The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole.
     A decline in the credit quality of an issuer or a provider of credit support (such as guarantees) or a maturity-shortening structure (such as demand and put features) for a security can cause the price of a security to decrease.

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000069441_contentCd_SST-LDI-PRO_RiskMember_LeverageRiskMember"
      id="ixv-29475">



      Leverage Risk.

     Leverage can increase market exposure, magnify investment risks, and cause losses to be realized more quickly.



   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000069441_contentCd_SST-LDI-PRO_RiskMember_RiskNotInsuredDepositoryInstitutionMember"
      id="ixv-29485">


     An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency

     .


   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000069441_contentCd_SST-LDI-PRO_RiskMember_RiskLoseMoneyMember"
      id="ixv-29493">


     &#160;

     You could lose money by investing in the fund.


   </oef:RiskTextBlock>
    <oef:BarChartAndPerformanceTableHeading
      contextRef="Pid_S000069441_contentCd_SST-LDI-PRO"
      id="ixv-29502">


     Performance


   </oef:BarChartAndPerformanceTableHeading>
    <oef:PerformanceNarrativeTextBlock
      contextRef="Pid_S000069441_contentCd_SST-LDI-PRO"
      id="ixv-29507">



       The following information is intended to help you understand the risks of investing in the fund.


      The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time.



     The additional index has characteristics relevant to the fund's investment strategies. Index descriptions appear

     in the "Additional Index Information" section of the prospectus.



      Past performance (before and after taxes) is not an indication of future performance.


     Visit



      www.fidelity.com


     for more recent performance information.

   </oef:PerformanceNarrativeTextBlock>
    <oef:PerformanceInformationIllustratesVariabilityOfReturns
      contextRef="Pid_S000069441_contentCd_SST-LDI-PRO"
      id="ixv-29513">

      The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time.

     </oef:PerformanceInformationIllustratesVariabilityOfReturns>
    <oef:PerformancePastDoesNotIndicateFuture
      contextRef="Pid_S000069441_contentCd_SST-LDI-PRO"
      id="ixv-29522">

      Past performance (before and after taxes) is not an indication of future performance.

     </oef:PerformancePastDoesNotIndicateFuture>
    <oef:PerformanceAvailabilityWebSiteAddress
      contextRef="Pid_S000069441_contentCd_SST-LDI-PRO"
      id="ixv-29528">

      www.fidelity.com
     </oef:PerformanceAvailabilityWebSiteAddress>
    <oef:BarChartHeading
      contextRef="Pid_S000069441_contentCd_SST-LDI-PRO"
      id="ixv-29533">


     Year-by-Year Returns

   </oef:BarChartHeading>
    <oef:AnnlRtrPct
      contextRef="Pid_S000069441_Cid_C000221556_2021"
      decimals="INF"
      id="ixv-101682"
      unitRef="pure">-0.0065</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000069441_Cid_C000221556_2022"
      decimals="INF"
      id="ixv-101683"
      unitRef="pure">-0.0347</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000069441_Cid_C000221556_2023"
      decimals="INF"
      id="ixv-101684"
      unitRef="pure">0.0520</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000069441_Cid_C000221556_2024"
      decimals="INF"
      id="ixv-101685"
      unitRef="pure">0.0470</oef:AnnlRtrPct>
    <oef:HighestQuarterlyReturnLabel
      contextRef="Pid_S000069441_contentCd_SST-LDI-PRO"
      id="ixv-29626">
          &#160;&#160;&#160;Highest Quarter Return
        </oef:HighestQuarterlyReturnLabel>
    <oef:BarChartHighestQuarterlyReturn
      contextRef="Pid_S000069441_contentCd_SST-LDI-PRO"
      decimals="4"
      id="ixv-101686"
      unitRef="pure">0.0296</oef:BarChartHighestQuarterlyReturn>
    <oef:BarChartHighestQuarterlyReturnDate
      contextRef="Pid_S000069441_contentCd_SST-LDI-PRO"
      id="ixv-29636">2024-09-30</oef:BarChartHighestQuarterlyReturnDate>
    <oef:LowestQuarterlyReturnLabel
      contextRef="Pid_S000069441_contentCd_SST-LDI-PRO"
      id="ixv-29641">
          &#160;&#160;&#160;Lowest Quarter Return
        </oef:LowestQuarterlyReturnLabel>
    <oef:BarChartLowestQuarterlyReturn
      contextRef="Pid_S000069441_contentCd_SST-LDI-PRO"
      decimals="4"
      id="ixv-101687"
      unitRef="pure">-0.0251</oef:BarChartLowestQuarterlyReturn>
    <oef:BarChartLowestQuarterlyReturnDate
      contextRef="Pid_S000069441_contentCd_SST-LDI-PRO"
      id="ixv-29652">2022-03-31</oef:BarChartLowestQuarterlyReturnDate>
    <oef:YearToDateReturnLabel
      contextRef="Pid_S000069441_contentCd_SST-LDI-PRO"
      id="ixv-29657">
          &#160;&#160;&#160;Year-to-Date Return
        </oef:YearToDateReturnLabel>
    <oef:BarChartYearToDateReturn
      contextRef="Pid_S000069441_contentCd_SST-LDI-PRO"
      decimals="4"
      id="ixv-101688"
      unitRef="pure">0.0440</oef:BarChartYearToDateReturn>
    <oef:BarChartYearToDateReturnDate
      contextRef="Pid_S000069441_contentCd_SST-LDI-PRO"
      id="ixv-29667">2025-09-30</oef:BarChartYearToDateReturnDate>
    <oef:PerformanceTableHeading
      contextRef="Pid_S000069441_contentCd_SST-LDI-PRO"
      id="ixv-29672">


     Average Annual Returns


   </oef:PerformanceTableHeading>
    <oef:PerformanceTableNarrativeTextBlock
      contextRef="Pid_S000069441_contentCd_SST-LDI-PRO"
      id="ixv-29677">




      After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes.



     Actual after-tax returns may differ depending on your individual circumstances.



      The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan).





      Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.




   </oef:PerformanceTableNarrativeTextBlock>
    <oef:PerformanceTableUsesHighestFederalRate
      contextRef="Pid_S000069441_contentCd_SST-LDI-PRO"
      id="ixv-29680">

      After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes.

     </oef:PerformanceTableUsesHighestFederalRate>
    <oef:PerformanceTableNotRelevantToTaxDeferred
      contextRef="Pid_S000069441_contentCd_SST-LDI-PRO"
      id="ixv-29687">

      The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan).

     </oef:PerformanceTableNotRelevantToTaxDeferred>
    <oef:PerformanceTableExplanationAfterTaxHigher
      contextRef="Pid_S000069441_contentCd_SST-LDI-PRO"
      id="ixv-29692">

      Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

     </oef:PerformanceTableExplanationAfterTaxHigher>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000069441_Cid_C000221556_ReturnBeforeTaxes_01"
      id="ixv-29730">
         Return Before Taxes
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000069441_Cid_C000221556_ReturnBeforeTaxes_01"
      decimals="4"
      id="ixv-101689"
      unitRef="pure">0.0470</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000069441_Cid_C000221556_ReturnBeforeTaxes_AverageAnnualReturnSinceInception"
      decimals="4"
      id="footnoteSST-LDI-PROS000069441AAR_A_RBT_loc"
      unitRef="pure">0.0139</oef:AvgAnnlRtrPct>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000069441_Cid_C000221556_AfterTaxesOnDistributions_01"
      id="ixv-29743">
         Return After Taxes on Distributions
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000069441_Cid_C000221556_AfterTaxesOnDistributions_01"
      decimals="4"
      id="ixv-101691"
      unitRef="pure">0.0303</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000069441_Cid_C000221556_AfterTaxesOnDistributions_AverageAnnualReturnSinceInception"
      decimals="4"
      id="footnoteSST-LDI-PROS000069441AAR_A_ATD_loc"
      unitRef="pure">0.0054</oef:AvgAnnlRtrPct>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000069441_Cid_C000221556_AfterTaxesOnDistributionsAndSales_01"
      id="ixv-29756">
         Return After Taxes on Distributions and Sale of Fund Shares
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000069441_Cid_C000221556_AfterTaxesOnDistributionsAndSales_01"
      decimals="4"
      id="ixv-101693"
      unitRef="pure">0.0290</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000069441_Cid_C000221556_AfterTaxesOnDistributionsAndSales_AverageAnnualReturnSinceInception"
      decimals="4"
      id="footnoteSST-LDI-PROS000069441AAR_A_ATDS_loc"
      unitRef="pure">0.0072</oef:AvgAnnlRtrPct>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000069441_Indexid_LB013_contentCd_SST-LDI-PRO_01"
      id="ixv-29770">
         Bloomberg U.S. 1-3 Year Government/Credit Bond Index
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000069441_Indexid_LB013_contentCd_SST-LDI-PRO_01"
      decimals="4"
      id="ixv-101695"
      unitRef="pure">0.0436</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000069441_Indexid_LB013_contentCd_SST-LDI-PRO_AverageAnnualReturnSinceInception"
      decimals="4"
      id="ixv-101696"
      unitRef="pure">0.0111</oef:AvgAnnlRtrPct>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000069441_Indexid_LB001_contentCd_SST-LDI-PRO_01"
      id="ixv-29789">
         Bloomberg U.S. Aggregate Bond Index
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000069441_Indexid_LB001_contentCd_SST-LDI-PRO_01"
      decimals="4"
      id="ixv-101697"
      unitRef="pure">0.0125</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000069441_Indexid_LB001_contentCd_SST-LDI-PRO_AverageAnnualReturnSinceInception"
      decimals="4"
      id="ixv-101698"
      unitRef="pure">-0.0194</oef:AvgAnnlRtrPct>
    <oef:AnnualReturnInceptionDate contextRef="Pid_S000069441_Cid_C000221556" id="ixv-29822">2020-09-15</oef:AnnualReturnInceptionDate>
    <oef:RiskReturnHeading
      contextRef="Pid_S000075287_contentCd_TBF-PRO"
      id="ixv-32324">


     Fund Summary

     Fund /Class:
     Fidelity&#xae; Tactical Bond Fund
     /Fidelity&#xae; Tactical Bond Fund

   </oef:RiskReturnHeading>
    <oef:ObjectiveHeading
      contextRef="Pid_S000075287_contentCd_TBF-PRO"
      id="ixv-32337">


     Investment Objective


   </oef:ObjectiveHeading>
    <oef:ObjectivePrimaryTextBlock
      contextRef="Pid_S000075287_contentCd_TBF-PRO"
      id="ixv-32342">


     Fidelity&#xae; Tactical Bond Fund seeks a high level of current income. Growth of capital may also be considered.


   </oef:ObjectivePrimaryTextBlock>
    <oef:ExpenseHeading
      contextRef="Pid_S000075287_contentCd_TBF-PRO"
      id="ixv-32347">


     Fee Table


   </oef:ExpenseHeading>
    <oef:ExpenseNarrativeTextBlock
      contextRef="Pid_S000075287_contentCd_TBF-PRO"
      id="ixv-32353">


     The following table describes the fees and expenses that may be incurred when you buy, hold, and sell shares of the fund. You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and examples below.

   </oef:ExpenseNarrativeTextBlock>
    <oef:ShareholderFeesCaption
      contextRef="Pid_S000075287_contentCd_TBF-PRO"
      id="ixv-32364">


     Shareholder fees


   </oef:ShareholderFeesCaption>
    <oef:ShareholderFeeOther
      contextRef="Pid_S000075287_contentCd_TBF-PRO"
      decimals="0"
      id="ixv-101699"
      unitRef="usd">0</oef:ShareholderFeeOther>
    <oef:OperatingExpensesCaption
      contextRef="Pid_S000075287_contentCd_TBF-PRO"
      id="ixv-32379">


     Annual Operating Expenses


   </oef:OperatingExpensesCaption>
    <oef:ManagementFeesOverAssets
      contextRef="Pid_S000075287_Cid_C000234189"
      decimals="6"
      id="ixv-101700"
      unitRef="pure">0.0063</oef:ManagementFeesOverAssets>
    <oef:DistributionAndService12b1FeesOverAssets
      contextRef="Pid_S000075287_Cid_C000234189"
      decimals="6"
      id="ixv-101701"
      unitRef="pure">0</oef:DistributionAndService12b1FeesOverAssets>
    <oef:OtherExpensesOverAssets
      contextRef="Pid_S000075287_Cid_C000234189"
      decimals="6"
      id="ixv-101702"
      unitRef="pure">0.0035</oef:OtherExpensesOverAssets>
    <oef:ExpensesOverAssets
      contextRef="Pid_S000075287_Cid_C000234189"
      decimals="6"
      id="ixv-101703"
      unitRef="pure">0.0098</oef:ExpensesOverAssets>
    <oef:FeeWaiverOrReimbursementOverAssets
      contextRef="Pid_S000075287_Cid_C000234189"
      decimals="6"
      id="footnoteS000075287TBF-PROAOE_AC000234189_FW"
      unitRef="pure">-0.0028</oef:FeeWaiverOrReimbursementOverAssets>
    <oef:NetExpensesOverAssets
      contextRef="Pid_S000075287_Cid_C000234189"
      decimals="6"
      id="ixv-101705"
      unitRef="pure">0.0070</oef:NetExpensesOverAssets>
    <oef:FeeWaiverOrReimbursementOverAssetsDateOfTermination
      contextRef="Pid_S000075287_contentCd_TBF-PRO"
      id="ixv-32454">2026-12-31</oef:FeeWaiverOrReimbursementOverAssetsDateOfTermination>
    <oef:ExpenseExampleNarrativeTextBlock
      contextRef="Pid_S000075287_contentCd_TBF-PRO"
      id="ixv-32463">


     This
     example

     helps compare the cost of investing in the fund with the cost of investing in other funds.

     Let's say, hypothetically, that the annual return for shares of the fund is 5% and that the fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated:

   </oef:ExpenseExampleNarrativeTextBlock>
    <oef:ExpenseExampleYear01
      contextRef="Pid_S000075287_Cid_C000234189"
      decimals="0"
      id="ixv-101706"
      unitRef="usd">72</oef:ExpenseExampleYear01>
    <oef:ExpenseExampleYear03
      contextRef="Pid_S000075287_Cid_C000234189"
      decimals="0"
      id="ixv-101707"
      unitRef="usd">274</oef:ExpenseExampleYear03>
    <oef:ExpenseExampleYear05
      contextRef="Pid_S000075287_Cid_C000234189"
      decimals="0"
      id="ixv-101708"
      unitRef="usd">505</oef:ExpenseExampleYear05>
    <oef:ExpenseExampleYear10
      contextRef="Pid_S000075287_Cid_C000234189"
      decimals="0"
      id="ixv-101709"
      unitRef="usd">1167</oef:ExpenseExampleYear10>
    <oef:PortfolioTurnoverHeading
      contextRef="Pid_S000075287_contentCd_TBF-PRO"
      id="ixv-32520">


     Portfolio Turnover


   </oef:PortfolioTurnoverHeading>
    <oef:PortfolioTurnoverTextBlock
      contextRef="Pid_S000075287_contentCd_TBF-PRO"
      id="ixv-32525">


     The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was



       30


     % of the average value of its portfolio.


   </oef:PortfolioTurnoverTextBlock>
    <oef:PortfolioTurnoverRate
      contextRef="Pid_S000075287_contentCd_TBF-PRO"
      decimals="4"
      id="ixv-101710"
      unitRef="pure">0.30</oef:PortfolioTurnoverRate>
    <oef:StrategyHeading
      contextRef="Pid_S000075287_contentCd_TBF-PRO"
      id="ixv-32534">


     Principal Investment Strategies


   </oef:StrategyHeading>
    <oef:StrategyNarrativeTextBlock
      contextRef="Pid_S000075287_contentCd_TBF-PRO"
      id="ixv-32539">




        Normally investing at least 80% of assets in debt securities of all types and repurchase agreements for those securities.

     Debt securities are used by issuers to borrow money. The issuer usually pays a fixed, variable, or floating rate of interest, and must repay the amount borrowed, usually at the maturity of the security. Debt securities include corporate bonds, government securities (including Treasury securities), repurchase agreements, money market securities, mortgage and other asset-backed securities, loans and loan participations, and other securities, such as hybrids and synthetic securities, believed to have debt-like characteristics (e.g., securities classified as Tier 2 Regulatory capital, securities that rank above share capital in an insolvency waterfall, securities with maturity dates and non-cancellable interest payment structures).&#160;
     A repurchase agreement is an agreement to buy a security at one price and a simultaneous agreement to sell it back at an agreed-upon price.
     Effective December 11, 2025, derivative instruments that provide investment exposure to the investments above or exposure to one or more market risk factors associated with such investments are included in the fund's 80% policy, consistent with the fund's investment policies and limitations with respect to investments in derivatives.
     &#160;

      Allocating assets across the full spectrum of the debt market, including investment-grade (those of medium and high quality), high yield and emerging markets debt securities across different maturities. In addition to the debt securities listed above, investments also will normally include lower-quality debt securities (those of less than investment-grade quality, also referred to as high yield debt securities or junk bonds), investment-grade securitized debt securities, floating rate loans and other floating rate securities, inflation-protected debt securities, preferred securities, contingent convertible securities, and securities of foreign issuers, including securities of issuers located in emerging markets. Emerging markets include countries that have an emerging stock market as defined by MSCI, countries or markets with low- to middle-income economies as classified by the World Bank, and other countries or markets that the Adviser identifies as having similar emerging markets characteristics.


      Investing in both U.S. dollar-denominated and non-U.S. dollar-denominated securities, and generally hedging the fund's foreign currency exposures utilizing forward foreign currency exchange contracts.
      Investing in collateralized loan obligations (CLO).
      Analyzing the credit quality of the issuer, security-specific features, current and potential future valuation, and trading opportunities to select investments.
      Engaging in transactions that have a leveraging effect on the fund, including investments in derivatives - such as swaps (interest rate, total return, and credit default), options, and futures contracts - and forward-settling securities, to adjust the fund's risk exposure.
      Investing in Fidelity's Central funds (specialized investment vehicles used by Fidelity&#xae; funds to invest in particular security types or investment disciplines) consistent with the asset classes discussed above.


   </oef:StrategyNarrativeTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000075287_contentCd_TBF-PRO_RiskMember_ImpairmentOfCollateralMember"
      id="ixv-32576">



      Impairment of Collateral.

     A floating rate loan may not be fully collateralized which may cause the floating rate loan to decline significantly in value.

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000075287_contentCd_TBF-PRO_RiskMember_FloatingRateLoanLiquidityMember"
      id="ixv-32585">



      Floating Rate Loan Liquidity.

     Floating rate loans generally are subject to restrictions on resale. Floating rate loans sometimes trade infrequently in the secondary market. As a result, valuing a floating rate loan can be more difficult, and buying and selling a floating rate loan at an acceptable price can be more difficult or delayed, including extended trade settlement periods. Difficulty in selling a floating rate loan can result in a loss.

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000075287_contentCd_TBF-PRO_RiskMember_InterestRateChangesMember"
      id="ixv-32594">



      Interest Rate Changes.

     Interest rate increases can cause the price of a debt security to decrease.

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000075287_contentCd_TBF-PRO_RiskMember_ForeignAndEmergingMarketsRiskMember"
      id="ixv-32603">



      Foreign and Emerging Markets Risk.

     Foreign markets, particularly emerging markets, can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market.
     The extent of economic development; political stability; market depth, infrastructure, and capitalization; and regulatory oversight can be less than in more developed markets. Emerging markets typically have less established legal, accounting and financial reporting systems than those in more developed markets, which may reduce the scope or quality of financial information available to investors.
     Emerging markets can be subject to greater social, economic, regulatory, and political uncertainties and can be extremely volatile.
     Foreign exchange rates also can be extremely volatile.

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000075287_contentCd_TBF-PRO_RiskMember_ForeignCurrencyTransactionsMember"
      id="ixv-32618">



      Foreign Currency Transactions.

     Although a forward foreign currency exchange contract is used to reduce or hedge a fund's exposure to changes in the value of the currency, suitable hedging transactions may not be available in all circumstances, may not be successful, and may eliminate any chance for the fund to benefit from favorable fluctuations in relevant foreign currencies.

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000075287_contentCd_TBF-PRO_RiskMember_PrepaymentMember"
      id="ixv-32627">



      Prepayment.

     The ability of an issuer of a debt security to repay principal prior to a security's maturity can cause greater price volatility if interest rates change.

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000075287_contentCd_TBF-PRO_RiskMember_IssuerSpecificChangesMember"
      id="ixv-32636">



      Issuer-Specific Changes.

     The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole.
     A decline in the credit quality of an issuer or a provider of credit support (such as guarantees) or a maturity-shortening structure (such as demand and put features) for a security can cause the price of a security to decrease.
     Lower-quality debt securities (those of less than investment-grade quality, also referred to as high yield debt securities or junk bonds) and certain types of other securities involve greater risk of default or price changes due to changes in the credit quality of the issuer. The value of lower-quality debt securities and certain types of other securities can be more volatile due to increased sensitivity to adverse issuer, political, regulatory, market, or economic developments and can be difficult to resell.
     CLO tranches can experience substantial losses due to actual and anticipated defaults, as well as aversion to CLO securities as a class.

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000075287_contentCd_TBF-PRO_RiskMember_ContingentConvertibleSecuritiesRiskMember"
      id="ixv-32655">



      Contingent Convertible Securities Risk.

     Contingent convertible securities have unique equity conversion or principal write-down features that involve additional risks, which may include cancellation of interest payments by the issuer or a regulatory authority; subordination to other creditors due to either a liquidation or other bankruptcy-related event or a conversion of the security from debt to equity; and a write-down of the security's principal amount.

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000075287_contentCd_TBF-PRO_RiskMember_LeverageRiskMember"
      id="ixv-32664">



      Leverage Risk.

     Leverage can increase market exposure, magnify investment risks, and cause losses to be realized more quickly.

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000075287_contentCd_TBF-PRO_RiskMember_InflationProtectedDebtExposureMember"
      id="ixv-32673">



      Inflation-Protected Debt Exposure.

     Increases in real interest rates can cause the price of inflation-protected debt securities to decrease. Interest payments on inflation-protected debt securities can be unpredictable.



   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000075287_contentCd_TBF-PRO_RiskMember_RiskNotInsuredDepositoryInstitutionMember"
      id="ixv-32683">


     An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency

     .


   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000075287_contentCd_TBF-PRO_RiskMember_RiskLoseMoneyMember"
      id="ixv-32691">


     &#160;

     You could lose money by investing in the fund.


   </oef:RiskTextBlock>
    <oef:BarChartAndPerformanceTableHeading
      contextRef="Pid_S000075287_contentCd_TBF-PRO"
      id="ixv-32700">


     Performance


   </oef:BarChartAndPerformanceTableHeading>
    <oef:PerformanceNarrativeTextBlock
      contextRef="Pid_S000075287_contentCd_TBF-PRO"
      id="ixv-32705">



       The following information is intended to help you understand the risks of investing in the fund.


      The information illustrates the
      changes in the
      performance of the fund's shares


      from year to
       year and compares the performance of the fund's shares to the performance of a securities market index over various periods of time.



     The index description appears in the "Additional Index Information" section of the prospectus.


      Past performance (before and after taxes) is not an indication of future performance.


     Visit



      www.fidelity.com


     for more recent performance information.

   </oef:PerformanceNarrativeTextBlock>
    <oef:PerformanceInformationIllustratesVariabilityOfReturns
      contextRef="Pid_S000075287_contentCd_TBF-PRO"
      id="ixv-32711">

      The information illustrates the
      changes in the
      performance of the fund's shares


      from year to
       year and compares the performance of the fund's shares to the performance of a securities market index over various periods of time.

     </oef:PerformanceInformationIllustratesVariabilityOfReturns>
    <oef:PerformancePastDoesNotIndicateFuture
      contextRef="Pid_S000075287_contentCd_TBF-PRO"
      id="ixv-32722">

      Past performance (before and after taxes) is not an indication of future performance.

     </oef:PerformancePastDoesNotIndicateFuture>
    <oef:PerformanceAvailabilityWebSiteAddress
      contextRef="Pid_S000075287_contentCd_TBF-PRO"
      id="ixv-32728">

      www.fidelity.com
     </oef:PerformanceAvailabilityWebSiteAddress>
    <oef:BarChartHeading
      contextRef="Pid_S000075287_contentCd_TBF-PRO"
      id="ixv-32733">


     Year-by-Year Returns

   </oef:BarChartHeading>
    <oef:AnnlRtrPct
      contextRef="Pid_S000075287_Cid_C000234189_2023"
      decimals="INF"
      id="ixv-101711"
      unitRef="pure">0.0704</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000075287_Cid_C000234189_2024"
      decimals="INF"
      id="ixv-101712"
      unitRef="pure">0.0147</oef:AnnlRtrPct>
    <oef:HighestQuarterlyReturnLabel
      contextRef="Pid_S000075287_contentCd_TBF-PRO"
      id="ixv-32818">
          &#160;&#160;&#160;Highest Quarter Return
        </oef:HighestQuarterlyReturnLabel>
    <oef:BarChartHighestQuarterlyReturn
      contextRef="Pid_S000075287_contentCd_TBF-PRO"
      decimals="4"
      id="ixv-101713"
      unitRef="pure">0.0690</oef:BarChartHighestQuarterlyReturn>
    <oef:BarChartHighestQuarterlyReturnDate
      contextRef="Pid_S000075287_contentCd_TBF-PRO"
      id="ixv-32828">2023-12-31</oef:BarChartHighestQuarterlyReturnDate>
    <oef:LowestQuarterlyReturnLabel
      contextRef="Pid_S000075287_contentCd_TBF-PRO"
      id="ixv-32833">
          &#160;&#160;&#160;Lowest Quarter Return
        </oef:LowestQuarterlyReturnLabel>
    <oef:BarChartLowestQuarterlyReturn
      contextRef="Pid_S000075287_contentCd_TBF-PRO"
      decimals="4"
      id="ixv-101714"
      unitRef="pure">-0.0324</oef:BarChartLowestQuarterlyReturn>
    <oef:BarChartLowestQuarterlyReturnDate
      contextRef="Pid_S000075287_contentCd_TBF-PRO"
      id="ixv-32844">2024-12-31</oef:BarChartLowestQuarterlyReturnDate>
    <oef:YearToDateReturnLabel
      contextRef="Pid_S000075287_contentCd_TBF-PRO"
      id="ixv-32849">
          &#160;&#160;&#160;Year-to-Date Return
        </oef:YearToDateReturnLabel>
    <oef:BarChartYearToDateReturn
      contextRef="Pid_S000075287_contentCd_TBF-PRO"
      decimals="4"
      id="ixv-101715"
      unitRef="pure">0.0678</oef:BarChartYearToDateReturn>
    <oef:BarChartYearToDateReturnDate
      contextRef="Pid_S000075287_contentCd_TBF-PRO"
      id="ixv-32859">2025-09-30</oef:BarChartYearToDateReturnDate>
    <oef:PerformanceTableHeading
      contextRef="Pid_S000075287_contentCd_TBF-PRO"
      id="ixv-32864">


     Average Annual Returns


   </oef:PerformanceTableHeading>
    <oef:PerformanceTableNarrativeTextBlock
      contextRef="Pid_S000075287_contentCd_TBF-PRO"
      id="ixv-32869">




      After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes.



     Actual after-tax returns may differ depending on your individual circumstances.



      The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan).





      Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.




   </oef:PerformanceTableNarrativeTextBlock>
    <oef:PerformanceTableUsesHighestFederalRate
      contextRef="Pid_S000075287_contentCd_TBF-PRO"
      id="ixv-32872">

      After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes.

     </oef:PerformanceTableUsesHighestFederalRate>
    <oef:PerformanceTableNotRelevantToTaxDeferred
      contextRef="Pid_S000075287_contentCd_TBF-PRO"
      id="ixv-32879">

      The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan).

     </oef:PerformanceTableNotRelevantToTaxDeferred>
    <oef:PerformanceTableExplanationAfterTaxHigher
      contextRef="Pid_S000075287_contentCd_TBF-PRO"
      id="ixv-32884">

      Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

     </oef:PerformanceTableExplanationAfterTaxHigher>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000075287_Cid_C000234189_ReturnBeforeTaxes_01"
      id="ixv-32923">
         Return Before Taxes
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000075287_Cid_C000234189_ReturnBeforeTaxes_01"
      decimals="4"
      id="ixv-101716"
      unitRef="pure">0.0147</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000075287_Cid_C000234189_ReturnBeforeTaxes_AverageAnnualReturnSinceInception"
      decimals="4"
      id="footnoteTBF-PROS000075287AAR_A_RBT_loc"
      unitRef="pure">-0.0051</oef:AvgAnnlRtrPct>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000075287_Cid_C000234189_AfterTaxesOnDistributions_01"
      id="ixv-32937">
         Return After Taxes on Distributions
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000075287_Cid_C000234189_AfterTaxesOnDistributions_01"
      decimals="4"
      id="ixv-101718"
      unitRef="pure">-0.0033</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000075287_Cid_C000234189_AfterTaxesOnDistributions_AverageAnnualReturnSinceInception"
      decimals="4"
      id="footnoteTBF-PROS000075287AAR_A_ATD_loc"
      unitRef="pure">-0.0226</oef:AvgAnnlRtrPct>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000075287_Cid_C000234189_AfterTaxesOnDistributionsAndSales_01"
      id="ixv-32952">
         Return After Taxes on Distributions and Sale of Fund Shares
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000075287_Cid_C000234189_AfterTaxesOnDistributionsAndSales_01"
      decimals="4"
      id="ixv-101720"
      unitRef="pure">0.0096</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000075287_Cid_C000234189_AfterTaxesOnDistributionsAndSales_AverageAnnualReturnSinceInception"
      decimals="4"
      id="footnoteTBF-PROS000075287AAR_A_ATDS_loc"
      unitRef="pure">-0.0111</oef:AvgAnnlRtrPct>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000075287_Indexid_LB001_contentCd_TBF-PRO_01"
      id="ixv-32967">
         Bloomberg U.S. Aggregate Bond Index
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000075287_Indexid_LB001_contentCd_TBF-PRO_01"
      decimals="4"
      id="ixv-101722"
      unitRef="pure">0.0125</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000075287_Indexid_LB001_contentCd_TBF-PRO_AverageAnnualReturnSinceInception"
      decimals="4"
      id="ixv-101723"
      unitRef="pure">-0.0109</oef:AvgAnnlRtrPct>
    <oef:AnnualReturnInceptionDate contextRef="Pid_S000075287_Cid_C000234189" id="ixv-33000">2022-02-10</oef:AnnualReturnInceptionDate>
    <oef:RiskReturnHeading
      contextRef="Pid_S000075287_contentCd_ATBF-PRO"
      id="ixv-35004">


     Fund Summary

     Fund /Class:
     Fidelity&#xae; Tactical Bond Fund
     /Fidelity Advisor&#xae; Tactical Bond Fund A, M, C, I, Z &#160;

   </oef:RiskReturnHeading>
    <oef:ObjectiveHeading
      contextRef="Pid_S000075287_contentCd_ATBF-PRO"
      id="ixv-35019">


     Investment Objective


   </oef:ObjectiveHeading>
    <oef:ObjectivePrimaryTextBlock
      contextRef="Pid_S000075287_contentCd_ATBF-PRO"
      id="ixv-35024">


     Fidelity&#xae; Tactical

     Bond Fund seeks a high level of current income.

     Growth of capital may also be considered.


   </oef:ObjectivePrimaryTextBlock>
    <oef:ExpenseHeading
      contextRef="Pid_S000075287_contentCd_ATBF-PRO"
      id="ixv-35033">


     Fee Table


   </oef:ExpenseHeading>
    <oef:ExpenseNarrativeTextBlock
      contextRef="Pid_S000075287_contentCd_ATBF-PRO"
      id="ixv-35039">


     The following table describes the fees and expenses that may be incurred when you buy, hold, and sell shares of the fund. You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and examples below.


      You may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $



       50,000



      in the fund or certain other Fidelity

      &#xae;

      funds. More information about these and other discounts is available from your investment professional and in the "Fund Distribution" section beginning on page 39

      of the prospectus



     and in

     the sales charge

     waiver appendix to

     the prospectus.

   </oef:ExpenseNarrativeTextBlock>
    <oef:ExpenseBreakpointDiscounts
      contextRef="Pid_S000075287_contentCd_ATBF-PRO"
      id="ixv-35045">

      You may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $



       50,000



      in the fund or certain other Fidelity

      &#xae;

      funds. More information about these and other discounts is available from your investment professional and in the "Fund Distribution" section beginning on page 39

      of the prospectus

     </oef:ExpenseBreakpointDiscounts>
    <oef:ExpenseBreakpointMinimumInvestmentRequiredAmount
      contextRef="Pid_S000075287_contentCd_ATBF-PRO"
      decimals="0"
      id="ixv-101724"
      unitRef="usd">50000</oef:ExpenseBreakpointMinimumInvestmentRequiredAmount>
    <oef:ShareholderFeesCaption
      contextRef="Pid_S000075287_contentCd_ATBF-PRO"
      id="ixv-35068">


     Shareholder fees


   </oef:ShareholderFeesCaption>
    <oef:MaximumCumulativeSalesChargeOverOfferingPrice
      contextRef="Pid_S000075287_Cid_C000234191"
      decimals="4"
      id="ixv-101725"
      unitRef="pure">0.0400</oef:MaximumCumulativeSalesChargeOverOfferingPrice>
    <oef:MaximumCumulativeSalesChargeOverOfferingPrice
      contextRef="Pid_S000075287_Cid_C000234193"
      decimals="4"
      id="ixv-101726"
      unitRef="pure">0.0400</oef:MaximumCumulativeSalesChargeOverOfferingPrice>
    <oef:MaximumCumulativeSalesChargeOverOfferingPrice
      contextRef="Pid_S000075287_Cid_C000234192"
      decimals="4"
      id="ixv-101727"
      unitRef="pure">0</oef:MaximumCumulativeSalesChargeOverOfferingPrice>
    <oef:MaximumCumulativeSalesChargeOverOfferingPrice
      contextRef="Pid_S000075287_Cid_C000234194"
      decimals="4"
      id="ixv-101728"
      unitRef="pure">0</oef:MaximumCumulativeSalesChargeOverOfferingPrice>
    <oef:MaximumCumulativeSalesChargeOverOfferingPrice
      contextRef="Pid_S000075287_Cid_C000234190"
      decimals="4"
      id="ixv-101729"
      unitRef="pure">0</oef:MaximumCumulativeSalesChargeOverOfferingPrice>
    <oef:MaximumDeferredSalesChargeOverOther
      contextRef="Pid_S000075287_Cid_C000234191"
      decimals="4"
      id="footnoteATBF-PROS000075287SHF_AC000234191"
      unitRef="pure">0</oef:MaximumDeferredSalesChargeOverOther>
    <oef:MaximumDeferredSalesChargeOverOther
      contextRef="Pid_S000075287_Cid_C000234193"
      decimals="4"
      id="footnoteATBF-PROS000075287SHF_AC000234193"
      unitRef="pure">0</oef:MaximumDeferredSalesChargeOverOther>
    <oef:MaximumDeferredSalesChargeOverOther
      contextRef="Pid_S000075287_Cid_C000234192"
      decimals="4"
      id="footnoteATBF-PROS000075287SHF_BC000234192"
      unitRef="pure">0.0100</oef:MaximumDeferredSalesChargeOverOther>
    <oef:MaximumDeferredSalesChargeOverOther
      contextRef="Pid_S000075287_Cid_C000234194"
      decimals="4"
      id="ixv-101733"
      unitRef="pure">0</oef:MaximumDeferredSalesChargeOverOther>
    <oef:MaximumDeferredSalesChargeOverOther
      contextRef="Pid_S000075287_Cid_C000234190"
      decimals="4"
      id="ixv-101734"
      unitRef="pure">0</oef:MaximumDeferredSalesChargeOverOther>
    <oef:ExpensesDeferredChargesTextBlock
      contextRef="Pid_S000075287_contentCd_ATBF-PRO"
      id="ixv-35174">

      Class A and Class M purchases of $1 million or more will not be subject to a front-end sales charge. Such Class A and Class M purchases may be subject, upon redemption, to a contingent deferred sales charge (CDSC) of 0.75% and 0.25%, respectively.

     </oef:ExpensesDeferredChargesTextBlock>
    <oef:ExpensesDeferredChargesTextBlock contextRef="Pid_S000075287_Cid_C000234192" id="ixv-35184">

      On Class C shares redeemed less than one year after purchase.

     </oef:ExpensesDeferredChargesTextBlock>
    <oef:OperatingExpensesCaption
      contextRef="Pid_S000075287_contentCd_ATBF-PRO"
      id="ixv-35189">


     Annual Operating Expenses


   </oef:OperatingExpensesCaption>
    <oef:ManagementFeesOverAssets
      contextRef="Pid_S000075287_Cid_C000234191"
      decimals="6"
      id="ixv-101735"
      unitRef="pure">0.0068</oef:ManagementFeesOverAssets>
    <oef:ManagementFeesOverAssets
      contextRef="Pid_S000075287_Cid_C000234193"
      decimals="6"
      id="ixv-101736"
      unitRef="pure">0.0071</oef:ManagementFeesOverAssets>
    <oef:ManagementFeesOverAssets
      contextRef="Pid_S000075287_Cid_C000234192"
      decimals="6"
      id="ixv-101737"
      unitRef="pure">0.0071</oef:ManagementFeesOverAssets>
    <oef:ManagementFeesOverAssets
      contextRef="Pid_S000075287_Cid_C000234194"
      decimals="6"
      id="ixv-101738"
      unitRef="pure">0.0071</oef:ManagementFeesOverAssets>
    <oef:ManagementFeesOverAssets
      contextRef="Pid_S000075287_Cid_C000234190"
      decimals="6"
      id="ixv-101739"
      unitRef="pure">0.0061</oef:ManagementFeesOverAssets>
    <oef:DistributionAndService12b1FeesOverAssets
      contextRef="Pid_S000075287_Cid_C000234191"
      decimals="6"
      id="ixv-101740"
      unitRef="pure">0.0025</oef:DistributionAndService12b1FeesOverAssets>
    <oef:DistributionAndService12b1FeesOverAssets
      contextRef="Pid_S000075287_Cid_C000234193"
      decimals="6"
      id="ixv-101741"
      unitRef="pure">0.0025</oef:DistributionAndService12b1FeesOverAssets>
    <oef:DistributionAndService12b1FeesOverAssets
      contextRef="Pid_S000075287_Cid_C000234192"
      decimals="6"
      id="ixv-101742"
      unitRef="pure">0.0100</oef:DistributionAndService12b1FeesOverAssets>
    <oef:DistributionAndService12b1FeesOverAssets
      contextRef="Pid_S000075287_Cid_C000234194"
      decimals="6"
      id="ixv-101743"
      unitRef="pure">0</oef:DistributionAndService12b1FeesOverAssets>
    <oef:DistributionAndService12b1FeesOverAssets
      contextRef="Pid_S000075287_Cid_C000234190"
      decimals="6"
      id="ixv-101744"
      unitRef="pure">0</oef:DistributionAndService12b1FeesOverAssets>
    <oef:OtherExpensesOverAssets
      contextRef="Pid_S000075287_Cid_C000234191"
      decimals="6"
      id="ixv-101745"
      unitRef="pure">0.0035</oef:OtherExpensesOverAssets>
    <oef:OtherExpensesOverAssets
      contextRef="Pid_S000075287_Cid_C000234193"
      decimals="6"
      id="ixv-101746"
      unitRef="pure">0.0035</oef:OtherExpensesOverAssets>
    <oef:OtherExpensesOverAssets
      contextRef="Pid_S000075287_Cid_C000234192"
      decimals="6"
      id="ixv-101747"
      unitRef="pure">0.0035</oef:OtherExpensesOverAssets>
    <oef:OtherExpensesOverAssets
      contextRef="Pid_S000075287_Cid_C000234194"
      decimals="6"
      id="ixv-101748"
      unitRef="pure">0.0040</oef:OtherExpensesOverAssets>
    <oef:OtherExpensesOverAssets
      contextRef="Pid_S000075287_Cid_C000234190"
      decimals="6"
      id="ixv-101749"
      unitRef="pure">0.0036</oef:OtherExpensesOverAssets>
    <oef:ExpensesOverAssets
      contextRef="Pid_S000075287_Cid_C000234191"
      decimals="6"
      id="ixv-101750"
      unitRef="pure">0.0128</oef:ExpensesOverAssets>
    <oef:ExpensesOverAssets
      contextRef="Pid_S000075287_Cid_C000234193"
      decimals="6"
      id="ixv-101751"
      unitRef="pure">0.0131</oef:ExpensesOverAssets>
    <oef:ExpensesOverAssets
      contextRef="Pid_S000075287_Cid_C000234192"
      decimals="6"
      id="ixv-101752"
      unitRef="pure">0.0206</oef:ExpensesOverAssets>
    <oef:ExpensesOverAssets
      contextRef="Pid_S000075287_Cid_C000234194"
      decimals="6"
      id="ixv-101753"
      unitRef="pure">0.0111</oef:ExpensesOverAssets>
    <oef:ExpensesOverAssets
      contextRef="Pid_S000075287_Cid_C000234190"
      decimals="6"
      id="ixv-101754"
      unitRef="pure">0.0097</oef:ExpensesOverAssets>
    <oef:FeeWaiverOrReimbursementOverAssets
      contextRef="Pid_S000075287_Cid_C000234191"
      decimals="6"
      id="footnoteS000075287ATBF-PROAOE_AC000234191_FW"
      unitRef="pure">-0.0033</oef:FeeWaiverOrReimbursementOverAssets>
    <oef:FeeWaiverOrReimbursementOverAssets
      contextRef="Pid_S000075287_Cid_C000234193"
      decimals="6"
      id="footnoteS000075287ATBF-PROAOE_AC000234193_FW"
      unitRef="pure">-0.0036</oef:FeeWaiverOrReimbursementOverAssets>
    <oef:FeeWaiverOrReimbursementOverAssets
      contextRef="Pid_S000075287_Cid_C000234192"
      decimals="6"
      id="footnoteS000075287ATBF-PROAOE_AC000234192_FW"
      unitRef="pure">-0.0036</oef:FeeWaiverOrReimbursementOverAssets>
    <oef:FeeWaiverOrReimbursementOverAssets
      contextRef="Pid_S000075287_Cid_C000234194"
      decimals="6"
      id="footnoteS000075287ATBF-PROAOE_AC000234194_FW"
      unitRef="pure">-0.0040</oef:FeeWaiverOrReimbursementOverAssets>
    <oef:FeeWaiverOrReimbursementOverAssets
      contextRef="Pid_S000075287_Cid_C000234190"
      decimals="6"
      id="footnoteS000075287ATBF-PROAOE_AC000234190_FW"
      unitRef="pure">-0.0035</oef:FeeWaiverOrReimbursementOverAssets>
    <oef:NetExpensesOverAssets
      contextRef="Pid_S000075287_Cid_C000234191"
      decimals="6"
      id="ixv-101760"
      unitRef="pure">0.0095</oef:NetExpensesOverAssets>
    <oef:NetExpensesOverAssets
      contextRef="Pid_S000075287_Cid_C000234193"
      decimals="6"
      id="ixv-101761"
      unitRef="pure">0.0095</oef:NetExpensesOverAssets>
    <oef:NetExpensesOverAssets
      contextRef="Pid_S000075287_Cid_C000234192"
      decimals="6"
      id="ixv-101762"
      unitRef="pure">0.0170</oef:NetExpensesOverAssets>
    <oef:NetExpensesOverAssets
      contextRef="Pid_S000075287_Cid_C000234194"
      decimals="6"
      id="footnoteS000075287ATBF-PROAOE_BC000234194_TW"
      unitRef="pure">0.0071</oef:NetExpensesOverAssets>
    <oef:NetExpensesOverAssets
      contextRef="Pid_S000075287_Cid_C000234190"
      decimals="6"
      id="footnoteS000075287ATBF-PROAOE_BC000234190_TW"
      unitRef="pure">0.0062</oef:NetExpensesOverAssets>
    <oef:FeeWaiverOrReimbursementOverAssetsDateOfTermination
      contextRef="Pid_S000075287_contentCd_ATBF-PRO"
      id="ixv-35436">2026-12-31</oef:FeeWaiverOrReimbursementOverAssetsDateOfTermination>
    <oef:ExpensesNotCorrelatedToRatioDueToAcquiredFundFees
      contextRef="Pid_S000075287_contentCd_ATBF-PRO"
      id="ixv-35454">

      Differs from the ratios of expenses to average net assets in the Financial Highlights section of the prospectus because of acquired fund fees and expenses. For the period, acquired fund fees and expenses are less than 0.01% and are included in other expenses. As a result, the total annual operating expenses after fee waiver and/or expense reimbursement in the fee table exceed the contractual expense limitation of the class.

     </oef:ExpensesNotCorrelatedToRatioDueToAcquiredFundFees>
    <oef:ExpenseExampleNarrativeTextBlock
      contextRef="Pid_S000075287_contentCd_ATBF-PRO"
      id="ixv-35459">


     This
     example

     helps compare the cost of investing in the fund with the cost of investing in other funds.

     Let's say, hypothetically, that the annual return for shares of the fund is 5% and that the fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated and if you hold your shares:

   </oef:ExpenseExampleNarrativeTextBlock>
    <oef:ExpenseExampleYear01
      contextRef="Pid_S000075287_Cid_C000234191"
      decimals="0"
      id="ixv-101765"
      unitRef="usd">493</oef:ExpenseExampleYear01>
    <oef:ExpenseExampleNoRedemptionYear01
      contextRef="Pid_S000075287_Cid_C000234191"
      decimals="0"
      id="ixv-101766"
      unitRef="usd">493</oef:ExpenseExampleNoRedemptionYear01>
    <oef:ExpenseExampleYear01
      contextRef="Pid_S000075287_Cid_C000234193"
      decimals="0"
      id="ixv-101767"
      unitRef="usd">493</oef:ExpenseExampleYear01>
    <oef:ExpenseExampleNoRedemptionYear01
      contextRef="Pid_S000075287_Cid_C000234193"
      decimals="0"
      id="ixv-101768"
      unitRef="usd">493</oef:ExpenseExampleNoRedemptionYear01>
    <oef:ExpenseExampleYear01
      contextRef="Pid_S000075287_Cid_C000234192"
      decimals="0"
      id="ixv-101769"
      unitRef="usd">273</oef:ExpenseExampleYear01>
    <oef:ExpenseExampleNoRedemptionYear01
      contextRef="Pid_S000075287_Cid_C000234192"
      decimals="0"
      id="ixv-101770"
      unitRef="usd">173</oef:ExpenseExampleNoRedemptionYear01>
    <oef:ExpenseExampleYear01
      contextRef="Pid_S000075287_Cid_C000234194"
      decimals="0"
      id="ixv-101771"
      unitRef="usd">73</oef:ExpenseExampleYear01>
    <oef:ExpenseExampleNoRedemptionYear01
      contextRef="Pid_S000075287_Cid_C000234194"
      decimals="0"
      id="ixv-101772"
      unitRef="usd">73</oef:ExpenseExampleNoRedemptionYear01>
    <oef:ExpenseExampleYear01
      contextRef="Pid_S000075287_Cid_C000234190"
      decimals="0"
      id="ixv-101773"
      unitRef="usd">63</oef:ExpenseExampleYear01>
    <oef:ExpenseExampleNoRedemptionYear01
      contextRef="Pid_S000075287_Cid_C000234190"
      decimals="0"
      id="ixv-101774"
      unitRef="usd">63</oef:ExpenseExampleNoRedemptionYear01>
    <oef:ExpenseExampleYear03
      contextRef="Pid_S000075287_Cid_C000234191"
      decimals="0"
      id="ixv-101775"
      unitRef="usd">747</oef:ExpenseExampleYear03>
    <oef:ExpenseExampleNoRedemptionYear03
      contextRef="Pid_S000075287_Cid_C000234191"
      decimals="0"
      id="ixv-101776"
      unitRef="usd">747</oef:ExpenseExampleNoRedemptionYear03>
    <oef:ExpenseExampleYear03
      contextRef="Pid_S000075287_Cid_C000234193"
      decimals="0"
      id="ixv-101777"
      unitRef="usd">753</oef:ExpenseExampleYear03>
    <oef:ExpenseExampleNoRedemptionYear03
      contextRef="Pid_S000075287_Cid_C000234193"
      decimals="0"
      id="ixv-101778"
      unitRef="usd">753</oef:ExpenseExampleNoRedemptionYear03>
    <oef:ExpenseExampleYear03
      contextRef="Pid_S000075287_Cid_C000234192"
      decimals="0"
      id="ixv-101779"
      unitRef="usd">599</oef:ExpenseExampleYear03>
    <oef:ExpenseExampleNoRedemptionYear03
      contextRef="Pid_S000075287_Cid_C000234192"
      decimals="0"
      id="ixv-101780"
      unitRef="usd">599</oef:ExpenseExampleNoRedemptionYear03>
    <oef:ExpenseExampleYear03
      contextRef="Pid_S000075287_Cid_C000234194"
      decimals="0"
      id="ixv-101781"
      unitRef="usd">299</oef:ExpenseExampleYear03>
    <oef:ExpenseExampleNoRedemptionYear03
      contextRef="Pid_S000075287_Cid_C000234194"
      decimals="0"
      id="ixv-101782"
      unitRef="usd">299</oef:ExpenseExampleNoRedemptionYear03>
    <oef:ExpenseExampleYear03
      contextRef="Pid_S000075287_Cid_C000234190"
      decimals="0"
      id="ixv-101783"
      unitRef="usd">262</oef:ExpenseExampleYear03>
    <oef:ExpenseExampleNoRedemptionYear03
      contextRef="Pid_S000075287_Cid_C000234190"
      decimals="0"
      id="ixv-101784"
      unitRef="usd">262</oef:ExpenseExampleNoRedemptionYear03>
    <oef:ExpenseExampleYear05
      contextRef="Pid_S000075287_Cid_C000234191"
      decimals="0"
      id="ixv-101785"
      unitRef="usd">1033</oef:ExpenseExampleYear05>
    <oef:ExpenseExampleNoRedemptionYear05
      contextRef="Pid_S000075287_Cid_C000234191"
      decimals="0"
      id="ixv-101786"
      unitRef="usd">1033</oef:ExpenseExampleNoRedemptionYear05>
    <oef:ExpenseExampleYear05
      contextRef="Pid_S000075287_Cid_C000234193"
      decimals="0"
      id="ixv-101787"
      unitRef="usd">1045</oef:ExpenseExampleYear05>
    <oef:ExpenseExampleNoRedemptionYear05
      contextRef="Pid_S000075287_Cid_C000234193"
      decimals="0"
      id="ixv-101788"
      unitRef="usd">1045</oef:ExpenseExampleNoRedemptionYear05>
    <oef:ExpenseExampleYear05
      contextRef="Pid_S000075287_Cid_C000234192"
      decimals="0"
      id="ixv-101789"
      unitRef="usd">1064</oef:ExpenseExampleYear05>
    <oef:ExpenseExampleNoRedemptionYear05
      contextRef="Pid_S000075287_Cid_C000234192"
      decimals="0"
      id="ixv-101790"
      unitRef="usd">1064</oef:ExpenseExampleNoRedemptionYear05>
    <oef:ExpenseExampleYear05
      contextRef="Pid_S000075287_Cid_C000234194"
      decimals="0"
      id="ixv-101791"
      unitRef="usd">559</oef:ExpenseExampleYear05>
    <oef:ExpenseExampleNoRedemptionYear05
      contextRef="Pid_S000075287_Cid_C000234194"
      decimals="0"
      id="ixv-101792"
      unitRef="usd">559</oef:ExpenseExampleNoRedemptionYear05>
    <oef:ExpenseExampleYear05
      contextRef="Pid_S000075287_Cid_C000234190"
      decimals="0"
      id="ixv-101793"
      unitRef="usd">490</oef:ExpenseExampleYear05>
    <oef:ExpenseExampleNoRedemptionYear05
      contextRef="Pid_S000075287_Cid_C000234190"
      decimals="0"
      id="ixv-101794"
      unitRef="usd">490</oef:ExpenseExampleNoRedemptionYear05>
    <oef:ExpenseExampleYear10
      contextRef="Pid_S000075287_Cid_C000234191"
      decimals="0"
      id="ixv-101795"
      unitRef="usd">1846</oef:ExpenseExampleYear10>
    <oef:ExpenseExampleNoRedemptionYear10
      contextRef="Pid_S000075287_Cid_C000234191"
      decimals="0"
      id="ixv-101796"
      unitRef="usd">1846</oef:ExpenseExampleNoRedemptionYear10>
    <oef:ExpenseExampleYear10
      contextRef="Pid_S000075287_Cid_C000234193"
      decimals="0"
      id="ixv-101797"
      unitRef="usd">1875</oef:ExpenseExampleYear10>
    <oef:ExpenseExampleNoRedemptionYear10
      contextRef="Pid_S000075287_Cid_C000234193"
      decimals="0"
      id="ixv-101798"
      unitRef="usd">1875</oef:ExpenseExampleNoRedemptionYear10>
    <oef:ExpenseExampleYear10
      contextRef="Pid_S000075287_Cid_C000234192"
      decimals="0"
      id="ixv-101799"
      unitRef="usd">2150</oef:ExpenseExampleYear10>
    <oef:ExpenseExampleNoRedemptionYear10
      contextRef="Pid_S000075287_Cid_C000234192"
      decimals="0"
      id="ixv-101800"
      unitRef="usd">2150</oef:ExpenseExampleNoRedemptionYear10>
    <oef:ExpenseExampleYear10
      contextRef="Pid_S000075287_Cid_C000234194"
      decimals="0"
      id="ixv-101801"
      unitRef="usd">1303</oef:ExpenseExampleYear10>
    <oef:ExpenseExampleNoRedemptionYear10
      contextRef="Pid_S000075287_Cid_C000234194"
      decimals="0"
      id="ixv-101802"
      unitRef="usd">1303</oef:ExpenseExampleNoRedemptionYear10>
    <oef:ExpenseExampleYear10
      contextRef="Pid_S000075287_Cid_C000234190"
      decimals="0"
      id="ixv-101803"
      unitRef="usd">1147</oef:ExpenseExampleYear10>
    <oef:ExpenseExampleNoRedemptionYear10
      contextRef="Pid_S000075287_Cid_C000234190"
      decimals="0"
      id="ixv-101804"
      unitRef="usd">1147</oef:ExpenseExampleNoRedemptionYear10>
    <oef:PortfolioTurnoverHeading
      contextRef="Pid_S000075287_contentCd_ATBF-PRO"
      id="ixv-35767">


     Portfolio Turnover


   </oef:PortfolioTurnoverHeading>
    <oef:PortfolioTurnoverTextBlock
      contextRef="Pid_S000075287_contentCd_ATBF-PRO"
      id="ixv-35772">


     The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was



       30


     % of the average value of its portfolio.


   </oef:PortfolioTurnoverTextBlock>
    <oef:PortfolioTurnoverRate
      contextRef="Pid_S000075287_contentCd_ATBF-PRO"
      decimals="4"
      id="ixv-101805"
      unitRef="pure">0.30</oef:PortfolioTurnoverRate>
    <oef:StrategyHeading
      contextRef="Pid_S000075287_contentCd_ATBF-PRO"
      id="ixv-35781">


     Principal Investment Strategies


   </oef:StrategyHeading>
    <oef:StrategyNarrativeTextBlock
      contextRef="Pid_S000075287_contentCd_ATBF-PRO"
      id="ixv-35786">




        Normally investing at least 80% of assets in debt securities of all types and repurchase agreements for those securities.

     Debt securities are used by issuers to borrow money. The issuer usually pays a fixed, variable, or floating rate of interest, and must repay the amount borrowed, usually at the maturity of the security. Debt securities include corporate bonds, government securities (including Treasury securities), repurchase agreements, money market securities, mortgage and other asset-backed securities, loans and loan participations, and other securities, such as hybrids and synthetic securities, believed to have debt-like characteristics (e.g., securities classified as Tier 2 Regulatory capital, securities that rank above share capital in an insolvency waterfall, securities with maturity dates and non-cancellable interest payment structures).&#160;
     A repurchase agreement is an agreement to buy a security at one price and a simultaneous agreement to sell it back at an agreed-upon price.
     Effective December 11, 2025, derivative instruments that provide investment exposure to the investments above or exposure to one or more market risk factors associated with such investments are included in the fund's 80% policy, consistent with the fund's investment policies and limitations with respect to investments in derivatives.
     &#160;

      Allocating assets across the full spectrum of the debt market, including investment-grade (those of medium and high quality), high yield and emerging markets debt securities across different maturities. In addition to the debt securities listed above, investments also will normally include lower-quality debt securities (those of less than investment-grade quality, also referred to as high yield debt securities or junk bonds), investment-grade securitized debt securities, floating rate loans and other floating rate securities, inflation-protected debt securities, preferred securities, contingent convertible securities, and securities of foreign issuers, including securities of issuers located in emerging markets. Emerging markets include countries that have an emerging stock market as defined by MSCI, countries or markets with low- to middle-income economies as classified by the World Bank, and other countries or markets that the Adviser identifies as having similar emerging markets characteristics.
      Investing in both U.S. dollar-denominated and non-U.S. dollar-denominated securities, and generally hedging the fund's foreign currency exposures utilizing forward foreign currency exchange contracts.
      Investing in collateralized loan obligations (CLO).
      Analyzing the credit quality of the issuer, security-specific features, current and potential future valuation, and trading opportunities to select investments.
      Engaging in transactions that have a leveraging effect on the fund, including investments in derivatives - such as swaps (interest rate, total return, and credit default), options, and futures contracts - and forward-settling securities, to adjust the fund's risk exposure.
      Investing in Fidelity's Central funds (specialized investment vehicles used by Fidelity&#xae; funds to invest in particular security types or investment disciplines) consistent with the asset classes discussed above.


   </oef:StrategyNarrativeTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000075287_contentCd_ATBF-PRO_RiskMember_ImpairmentOfCollateralMember"
      id="ixv-35822">



      Impairment of Collateral.

     A floating rate loan may not be fully collateralized which may cause the floating rate loan to decline significantly in value.

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000075287_contentCd_ATBF-PRO_RiskMember_FloatingRateLoanLiquidityMember"
      id="ixv-35831">



      Floating Rate Loan Liquidity.

     Floating rate loans generally are subject to restrictions on resale. Floating rate loans sometimes trade infrequently in the secondary market. As a result, valuing a floating rate loan can be more difficult, and buying and selling a floating rate loan at an acceptable price can be more difficult or delayed, including extended trade settlement periods. Difficulty in selling a floating rate loan can result in a loss.

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000075287_contentCd_ATBF-PRO_RiskMember_InterestRateChangesMember"
      id="ixv-35840">



      Interest Rate Changes.

     Interest rate increases can cause the price of a debt security to decrease.

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000075287_contentCd_ATBF-PRO_RiskMember_ForeignAndEmergingMarketsRiskMember"
      id="ixv-35849">



      Foreign and Emerging Markets Risk.

     Foreign markets, particularly emerging markets, can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market.
     The extent of economic development; political stability; market depth, infrastructure, and capitalization; and regulatory oversight can be less than in more developed markets. Emerging markets typically have less established legal, accounting and financial reporting systems than those in more developed markets, which may reduce the scope or quality of financial information available to investors.
     Emerging markets can be subject to greater social, economic, regulatory, and political uncertainties and can be extremely volatile.
     Foreign exchange rates also can be extremely volatile.

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000075287_contentCd_ATBF-PRO_RiskMember_ForeignCurrencyTransactionsMember"
      id="ixv-35864">



      Foreign Currency Transactions.

     Although a forward foreign currency exchange contract is used to reduce or hedge a fund's exposure to changes in the value of the currency, suitable hedging transactions may not be available in all circumstances, may not be successful, and may eliminate any chance for the fund to benefit from favorable fluctuations in relevant foreign currencies.

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000075287_contentCd_ATBF-PRO_RiskMember_PrepaymentMember"
      id="ixv-35873">



      Prepayment.

     The ability of an issuer of a debt security to repay principal prior to a security's maturity can cause greater price volatility if interest rates change.

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000075287_contentCd_ATBF-PRO_RiskMember_IssuerSpecificChangesMember"
      id="ixv-35882">



      Issuer-Specific Changes.

     The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole.
     A decline in the credit quality of an issuer or a provider of credit support (such as guarantees) or a maturity-shortening structure (such as demand and put features) for a security can cause the price of a security to decrease.
     Lower-quality debt securities (those of less than investment-grade quality, also referred to as high yield debt securities or junk bonds) and certain types of other securities involve greater risk of default or price changes due to changes in the credit quality of the issuer. The value of lower-quality debt securities and certain types of other securities can be more volatile due to increased sensitivity to adverse issuer, political, regulatory, market, or economic developments and can be difficult to resell.
     CLO tranches can experience substantial losses due to actual and anticipated defaults, as well as aversion to CLO securities as a class.

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000075287_contentCd_ATBF-PRO_RiskMember_ContingentConvertibleSecuritiesRiskMember"
      id="ixv-35901">



      Contingent Convertible Securities Risk.

     Contingent convertible securities have unique equity conversion or principal write-down features that involve additional risks, which may include cancellation of interest payments by the issuer or a regulatory authority; subordination to other creditors due to either a liquidation or other bankruptcy-related event or a conversion of the security from debt to equity; and a write-down of the security's principal amount.

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000075287_contentCd_ATBF-PRO_RiskMember_LeverageRiskMember"
      id="ixv-35910">



      Leverage Risk.

     Leverage can increase market exposure, magnify investment risks, and cause losses to be realized more quickly.

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000075287_contentCd_ATBF-PRO_RiskMember_InflationProtectedDebtExposureMember"
      id="ixv-35919">



      Inflation-Protected Debt Exposure.

     Increases in real interest rates can cause the price of inflation-protected debt securities to decrease. Interest payments on inflation-protected debt securities can be unpredictable.



   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000075287_contentCd_ATBF-PRO_RiskMember_RiskNotInsuredDepositoryInstitutionMember"
      id="ixv-35929">


     An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency

     .


   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000075287_contentCd_ATBF-PRO_RiskMember_RiskLoseMoneyMember"
      id="ixv-35937">


     &#160;

     You could lose money by investing in the fund.


   </oef:RiskTextBlock>
    <oef:BarChartAndPerformanceTableHeading
      contextRef="Pid_S000075287_contentCd_ATBF-PRO"
      id="ixv-35946">


     Performance


   </oef:BarChartAndPerformanceTableHeading>
    <oef:PerformanceNarrativeTextBlock
      contextRef="Pid_S000075287_contentCd_ATBF-PRO"
      id="ixv-35951">



       The following information is intended to help you understand the risks of investing in the fund.


      The information illustrates the
      changes in the
      performance of the fund's shares


      from year to

      year and compares the performance of the fund's shares to the performance of a securities market index over various periods of time.



     The index description appears

     in the "Additional Index Information" section of the prospectus.



      Past performance (before and after taxes) is not an indication of future performance.


     Visit



      institutional.fidelity.com


     for more recent performance information.

   </oef:PerformanceNarrativeTextBlock>
    <oef:PerformanceInformationIllustratesVariabilityOfReturns
      contextRef="Pid_S000075287_contentCd_ATBF-PRO"
      id="ixv-35957">

      The information illustrates the
      changes in the
      performance of the fund's shares


      from year to

      year and compares the performance of the fund's shares to the performance of a securities market index over various periods of time.

     </oef:PerformanceInformationIllustratesVariabilityOfReturns>
    <oef:PerformancePastDoesNotIndicateFuture
      contextRef="Pid_S000075287_contentCd_ATBF-PRO"
      id="ixv-35972">

      Past performance (before and after taxes) is not an indication of future performance.

     </oef:PerformancePastDoesNotIndicateFuture>
    <oef:PerformanceAvailabilityWebSiteAddress
      contextRef="Pid_S000075287_contentCd_ATBF-PRO"
      id="ixv-35978">

      institutional.fidelity.com
     </oef:PerformanceAvailabilityWebSiteAddress>
    <oef:BarChartHeading
      contextRef="Pid_S000075287_contentCd_ATBF-PRO"
      id="ixv-35983">


     Year-by-Year Returns

   </oef:BarChartHeading>
    <oef:BarChartNarrativeTextBlock
      contextRef="Pid_S000075287_contentCd_ATBF-PRO"
      id="ixv-35987">




      The returns in the bar chart do not reflect any applicable sales charges; if sales charges were reflected, returns would be lower than those shown.




   </oef:BarChartNarrativeTextBlock>
    <oef:BarChartDoesNotReflectSalesLoads
      contextRef="Pid_S000075287_contentCd_ATBF-PRO"
      id="ixv-35990">

      The returns in the bar chart do not reflect any applicable sales charges; if sales charges were reflected, returns would be lower than those shown.

     </oef:BarChartDoesNotReflectSalesLoads>
    <oef:AnnlRtrPct
      contextRef="Pid_S000075287_Cid_C000234191_2023"
      decimals="INF"
      id="ixv-101806"
      unitRef="pure">0.0678</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000075287_Cid_C000234191_2024"
      decimals="INF"
      id="ixv-101807"
      unitRef="pure">0.0122</oef:AnnlRtrPct>
    <oef:HighestQuarterlyReturnLabel
      contextRef="Pid_S000075287_contentCd_ATBF-PRO"
      id="ixv-36076">
          &#160;&#160;&#160;Highest Quarter Return
        </oef:HighestQuarterlyReturnLabel>
    <oef:BarChartHighestQuarterlyReturn
      contextRef="Pid_S000075287_contentCd_ATBF-PRO"
      decimals="4"
      id="ixv-101808"
      unitRef="pure">0.0683</oef:BarChartHighestQuarterlyReturn>
    <oef:BarChartHighestQuarterlyReturnDate
      contextRef="Pid_S000075287_contentCd_ATBF-PRO"
      id="ixv-36086">2023-12-31</oef:BarChartHighestQuarterlyReturnDate>
    <oef:LowestQuarterlyReturnLabel
      contextRef="Pid_S000075287_contentCd_ATBF-PRO"
      id="ixv-36091">
          &#160;&#160;&#160;Lowest Quarter Return
        </oef:LowestQuarterlyReturnLabel>
    <oef:BarChartLowestQuarterlyReturn
      contextRef="Pid_S000075287_contentCd_ATBF-PRO"
      decimals="4"
      id="ixv-101809"
      unitRef="pure">-0.0330</oef:BarChartLowestQuarterlyReturn>
    <oef:BarChartLowestQuarterlyReturnDate
      contextRef="Pid_S000075287_contentCd_ATBF-PRO"
      id="ixv-36102">2024-12-31</oef:BarChartLowestQuarterlyReturnDate>
    <oef:YearToDateReturnLabel
      contextRef="Pid_S000075287_contentCd_ATBF-PRO"
      id="ixv-36107">
          &#160;&#160;&#160;Year-to-Date Return
        </oef:YearToDateReturnLabel>
    <oef:BarChartYearToDateReturn
      contextRef="Pid_S000075287_contentCd_ATBF-PRO"
      decimals="4"
      id="ixv-101810"
      unitRef="pure">0.0658</oef:BarChartYearToDateReturn>
    <oef:BarChartYearToDateReturnDate
      contextRef="Pid_S000075287_contentCd_ATBF-PRO"
      id="ixv-36117">2025-09-30</oef:BarChartYearToDateReturnDate>
    <oef:PerformanceTableHeading
      contextRef="Pid_S000075287_contentCd_ATBF-PRO"
      id="ixv-36122">


     Average Annual Returns


   </oef:PerformanceTableHeading>
    <oef:PerformanceTableNarrativeTextBlock
      contextRef="Pid_S000075287_contentCd_ATBF-PRO"
      id="ixv-36128">




      Unlike the returns in the bar chart, the returns in the table reflect the maximum applicable sales charges.





      After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes.





      After-tax returns for Class A are shown in the table below and after-tax returns for other classes will vary.



     Actual after-tax returns may differ depending on your individual circumstances.


      The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan).




      Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.




   </oef:PerformanceTableNarrativeTextBlock>
    <oef:PerformanceTableDoesReflectSalesLoads
      contextRef="Pid_S000075287_contentCd_ATBF-PRO"
      id="ixv-36131">

      Unlike the returns in the bar chart, the returns in the table reflect the maximum applicable sales charges.

     </oef:PerformanceTableDoesReflectSalesLoads>
    <oef:PerformanceTableUsesHighestFederalRate
      contextRef="Pid_S000075287_contentCd_ATBF-PRO"
      id="ixv-36136">

      After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes.

     </oef:PerformanceTableUsesHighestFederalRate>
    <oef:PerformanceTableOneClassOfAfterTaxShown
      contextRef="Pid_S000075287_contentCd_ATBF-PRO"
      id="ixv-36141">

      After-tax returns for Class A are shown in the table below and after-tax returns for other classes will vary.

     </oef:PerformanceTableOneClassOfAfterTaxShown>
    <oef:PerformanceTableNotRelevantToTaxDeferred
      contextRef="Pid_S000075287_contentCd_ATBF-PRO"
      id="ixv-36147">

      The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan).
     </oef:PerformanceTableNotRelevantToTaxDeferred>
    <oef:PerformanceTableExplanationAfterTaxHigher
      contextRef="Pid_S000075287_contentCd_ATBF-PRO"
      id="ixv-36151">

      Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

     </oef:PerformanceTableExplanationAfterTaxHigher>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000075287_Cid_C000234191_ReturnBeforeTaxes_01"
      id="ixv-36177">
         Return Before Taxes
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000075287_Cid_C000234191_ReturnBeforeTaxes_01"
      decimals="4"
      id="ixv-101811"
      unitRef="pure">-0.0283</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000075287_Cid_C000234191_ReturnBeforeTaxes_AverageAnnualReturnSinceInception"
      decimals="4"
      id="footnoteATBF-PROS000075287AAR_A_RBT_loc"
      unitRef="pure">-0.0215</oef:AvgAnnlRtrPct>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000075287_Cid_C000234191_AfterTaxesOnDistributions_01"
      id="ixv-36194">
         Return After Taxes on Distributions
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000075287_Cid_C000234191_AfterTaxesOnDistributions_01"
      decimals="4"
      id="ixv-101813"
      unitRef="pure">-0.0452</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000075287_Cid_C000234191_AfterTaxesOnDistributions_AverageAnnualReturnSinceInception"
      decimals="4"
      id="footnoteATBF-PROS000075287AAR_A_ATD_loc"
      unitRef="pure">-0.0379</oef:AvgAnnlRtrPct>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000075287_Cid_C000234191_AfterTaxesOnDistributionsAndSales_01"
      id="ixv-36209">
          Return After Taxes on Distributions and Sale of Fund Shares
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000075287_Cid_C000234191_AfterTaxesOnDistributionsAndSales_01"
      decimals="4"
      id="ixv-101815"
      unitRef="pure">-0.0165</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000075287_Cid_C000234191_AfterTaxesOnDistributionsAndSales_AverageAnnualReturnSinceInception"
      decimals="4"
      id="footnoteATBF-PROS000075287AAR_A_ATDS_loc"
      unitRef="pure">-0.0231</oef:AvgAnnlRtrPct>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000075287_Cid_C000234193_ReturnBeforeTaxes_01"
      id="ixv-36224">
         Return Before Taxes
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000075287_Cid_C000234193_ReturnBeforeTaxes_01"
      decimals="4"
      id="ixv-101817"
      unitRef="pure">-0.0283</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000075287_Cid_C000234193_ReturnBeforeTaxes_AverageAnnualReturnSinceInception"
      decimals="4"
      id="footnoteATBF-PROS000075287AAR_B_RBT_loc"
      unitRef="pure">-0.0215</oef:AvgAnnlRtrPct>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000075287_Cid_C000234192_ReturnBeforeTaxes_01"
      id="ixv-36239">
         Return Before Taxes
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000075287_Cid_C000234192_ReturnBeforeTaxes_01"
      decimals="4"
      id="ixv-101819"
      unitRef="pure">-0.0051</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000075287_Cid_C000234192_ReturnBeforeTaxes_AverageAnnualReturnSinceInception"
      decimals="4"
      id="footnoteATBF-PROS000075287AAR_C_RBT_loc"
      unitRef="pure">-0.0149</oef:AvgAnnlRtrPct>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000075287_Cid_C000234194_ReturnBeforeTaxes_01"
      id="ixv-36254">
         Return Before Taxes
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000075287_Cid_C000234194_ReturnBeforeTaxes_01"
      decimals="4"
      id="ixv-101821"
      unitRef="pure">0.0147</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000075287_Cid_C000234194_ReturnBeforeTaxes_AverageAnnualReturnSinceInception"
      decimals="4"
      id="footnoteATBF-PROS000075287AAR_D_RBT_loc"
      unitRef="pure">-0.0051</oef:AvgAnnlRtrPct>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000075287_Cid_C000234190_ReturnBeforeTaxes_01"
      id="ixv-36268">
         Return Before Taxes
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000075287_Cid_C000234190_ReturnBeforeTaxes_01"
      decimals="4"
      id="ixv-101823"
      unitRef="pure">0.0156</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000075287_Cid_C000234190_ReturnBeforeTaxes_AverageAnnualReturnSinceInception"
      decimals="4"
      id="footnoteATBF-PROS000075287AAR_E_RBT_loc"
      unitRef="pure">-0.0042</oef:AvgAnnlRtrPct>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000075287_Indexid_LB001_contentCd_ATBF-PRO_01"
      id="ixv-36281">
         Bloomberg U.S. Aggregate Bond Index
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000075287_Indexid_LB001_contentCd_ATBF-PRO_01"
      decimals="4"
      id="ixv-101825"
      unitRef="pure">0.0125</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000075287_Indexid_LB001_contentCd_ATBF-PRO_AverageAnnualReturnSinceInception"
      decimals="4"
      id="ixv-101826"
      unitRef="pure">-0.0109</oef:AvgAnnlRtrPct>
    <oef:AnnualReturnInceptionDate contextRef="Pid_S000075287_Cid_C000234191" id="ixv-36314">2022-02-10</oef:AnnualReturnInceptionDate>
    <oef:AnnualReturnInceptionDate contextRef="Pid_S000075287_Cid_C000234193" id="ixv-36328">2022-02-10</oef:AnnualReturnInceptionDate>
    <oef:AnnualReturnInceptionDate contextRef="Pid_S000075287_Cid_C000234192" id="ixv-36341">2022-02-10</oef:AnnualReturnInceptionDate>
    <oef:AnnualReturnInceptionDate contextRef="Pid_S000075287_Cid_C000234194" id="ixv-36354">2022-02-10</oef:AnnualReturnInceptionDate>
    <oef:AnnualReturnInceptionDate contextRef="Pid_S000075287_Cid_C000234190" id="ixv-36367">2022-02-10</oef:AnnualReturnInceptionDate>
    <oef:RiskReturnHeading
      contextRef="Pid_S000075889_contentCd_SSU-PRO"
      id="ixv-42329">


     Fund Summary

     Fund:
     Fidelity&#xae; SAI Sustainable Core Plus Bond Fund

   </oef:RiskReturnHeading>
    <oef:ObjectiveHeading
      contextRef="Pid_S000075889_contentCd_SSU-PRO"
      id="ixv-42338">


     Investment Objective


   </oef:ObjectiveHeading>
    <oef:ObjectivePrimaryTextBlock
      contextRef="Pid_S000075889_contentCd_SSU-PRO"
      id="ixv-42343">


     Fidelity&#xae; SAI Sustainable Core Plus Bond Fund seeks a high level of current income.


   </oef:ObjectivePrimaryTextBlock>
    <oef:ExpenseHeading
      contextRef="Pid_S000075889_contentCd_SSU-PRO"
      id="ixv-42348">


     Fee Table


   </oef:ExpenseHeading>
    <oef:ExpenseNarrativeTextBlock
      contextRef="Pid_S000075889_contentCd_SSU-PRO"
      id="ixv-42354">


     The following table describes the fees and expenses that may be incurred when you buy, hold, and sell shares of the fund.

   </oef:ExpenseNarrativeTextBlock>
    <oef:ShareholderFeesCaption
      contextRef="Pid_S000075889_contentCd_SSU-PRO"
      id="ixv-42364">


     Shareholder fees


   </oef:ShareholderFeesCaption>
    <oef:ShareholderFeeOther
      contextRef="Pid_S000075889_contentCd_SSU-PRO"
      decimals="0"
      id="ixv-101827"
      unitRef="usd">0</oef:ShareholderFeeOther>
    <oef:OperatingExpensesCaption
      contextRef="Pid_S000075889_contentCd_SSU-PRO"
      id="ixv-42379">


     Annual Operating Expenses


   </oef:OperatingExpensesCaption>
    <oef:ManagementFeesOverAssets
      contextRef="Pid_S000075889_Cid_C000235214"
      decimals="6"
      id="ixv-101828"
      unitRef="pure">0.0028</oef:ManagementFeesOverAssets>
    <oef:DistributionAndService12b1FeesOverAssets
      contextRef="Pid_S000075889_Cid_C000235214"
      decimals="6"
      id="ixv-101829"
      unitRef="pure">0</oef:DistributionAndService12b1FeesOverAssets>
    <oef:OtherExpensesOverAssets
      contextRef="Pid_S000075889_Cid_C000235214"
      decimals="6"
      id="ixv-101830"
      unitRef="pure">0.0021</oef:OtherExpensesOverAssets>
    <oef:ExpensesOverAssets
      contextRef="Pid_S000075889_Cid_C000235214"
      decimals="6"
      id="ixv-101831"
      unitRef="pure">0.0049</oef:ExpensesOverAssets>
    <oef:FeeWaiverOrReimbursementOverAssets
      contextRef="Pid_S000075889_Cid_C000235214"
      decimals="6"
      id="footnoteS000075889SSU-PROAOE_AC000235214_FW"
      unitRef="pure">-0.0013</oef:FeeWaiverOrReimbursementOverAssets>
    <oef:NetExpensesOverAssets
      contextRef="Pid_S000075889_Cid_C000235214"
      decimals="6"
      id="ixv-101833"
      unitRef="pure">0.0036</oef:NetExpensesOverAssets>
    <oef:FeeWaiverOrReimbursementOverAssetsDateOfTermination
      contextRef="Pid_S000075889_contentCd_SSU-PRO"
      id="ixv-42454">2026-12-31</oef:FeeWaiverOrReimbursementOverAssetsDateOfTermination>
    <oef:ExpenseExampleNarrativeTextBlock
      contextRef="Pid_S000075889_contentCd_SSU-PRO"
      id="ixv-42463">


     This
     example

     helps compare the cost of investing in the fund with the cost of investing in other funds.

     Let's say, hypothetically, that the annual return for shares of the fund is 5% and that the fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated:

   </oef:ExpenseExampleNarrativeTextBlock>
    <oef:ExpenseExampleYear01
      contextRef="Pid_S000075889_Cid_C000235214"
      decimals="0"
      id="ixv-101834"
      unitRef="usd">37</oef:ExpenseExampleYear01>
    <oef:ExpenseExampleYear03
      contextRef="Pid_S000075889_Cid_C000235214"
      decimals="0"
      id="ixv-101835"
      unitRef="usd">139</oef:ExpenseExampleYear03>
    <oef:ExpenseExampleYear05
      contextRef="Pid_S000075889_Cid_C000235214"
      decimals="0"
      id="ixv-101836"
      unitRef="usd">257</oef:ExpenseExampleYear05>
    <oef:ExpenseExampleYear10
      contextRef="Pid_S000075889_Cid_C000235214"
      decimals="0"
      id="ixv-101837"
      unitRef="usd">599</oef:ExpenseExampleYear10>
    <oef:PortfolioTurnoverHeading
      contextRef="Pid_S000075889_contentCd_SSU-PRO"
      id="ixv-42520">


     Portfolio Turnover


   </oef:PortfolioTurnoverHeading>
    <oef:PortfolioTurnoverTextBlock
      contextRef="Pid_S000075889_contentCd_SSU-PRO"
      id="ixv-42525">


     The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was



       210


     % of the average value of its portfolio.


   </oef:PortfolioTurnoverTextBlock>
    <oef:PortfolioTurnoverRate
      contextRef="Pid_S000075889_contentCd_SSU-PRO"
      decimals="4"
      id="ixv-101838"
      unitRef="pure">2.10</oef:PortfolioTurnoverRate>
    <oef:StrategyHeading
      contextRef="Pid_S000075889_contentCd_SSU-PRO"
      id="ixv-42534">


     Principal Investment Strategies


   </oef:StrategyHeading>
    <oef:StrategyNarrativeTextBlock
      contextRef="Pid_S000075889_contentCd_SSU-PRO"
      id="ixv-42539">




        Normally investing at least 80% of assets in debt securities of all types that Fidelity Management &amp; Research Company LLC (FMR) (the Adviser) believes have positive environmental, social and governance (ESG) characteristics and repurchase agreements for those securities.

     Debt securities are used by issuers to borrow money. The issuer usually pays a fixed, variable, or floating rate of interest, and must repay the amount borrowed, usually at the maturity of the security. Debt securities include corporate bonds, government securities (including Treasury securities), repurchase agreements, money market securities, mortgage and other asset-backed securities, loans and loan participations, and other securities, such as hybrids and synthetic securities, believed to have debt-like characteristics (e.g., securities classified as Tier 2 Regulatory capital, securities that rank above share capital in an insolvency waterfall, securities with maturity dates and non-cancellable interest payment structures).&#160;
     A repurchase agreement is an agreement to buy a security at one price and a simultaneous agreement to sell it back at an agreed-upon price.
     Effective December 11, 2025, derivative instruments that provide investment exposure to the investments above or exposure to one or more market risk factors associated with such investments are included in the fund's 80% policy, consistent with the fund's investment policies and limitations with respect to investments in derivatives.
     &#160;

      Evaluating each security in which the fund invests using both a traditional bond credit, structure and relative value analysis and a consideration of the Adviser's judgment about the security's ESG characteristics. When assessing a security's ESG characteristics and its eligibility for purchase, the Adviser considers the following, where available: (i) the sustainability practices of the security's issuer or sponsor, as applicable (each, an "issuer"), based on an evaluation of such issuer's individual ESG profile; (ii) ESG factors related to the security's underlying pool of assets; and (iii) any third-party designation as a green, sustainable or sustainability-linked bond. A security's positive ESG characteristics can be determined under any of those three factors.
      Using the Adviser's proprietary ESG ratings process to evaluate the current state of an issuer's sustainability practices using a data-driven framework that includes both proprietary and third-party data, and also provide a qualitative forward-looking assessment of an issuer's sustainability outlook provided by the Adviser's fundamental research analysts and ESG team.
      The Adviser's ESG ratings of issuers are derived from multiple factors, including an issuer's environmental profile, which may include, but is not limited to, carbon and toxic emissions, water management, waste management, vulnerability to the physical impacts of climate change, and research and investment into products, services, and energies that reduce emissions and/or provide opportunities to transition to less carbon-intensive products or operations. An assessment of an issuer's social profile includes, but is not limited to, its approach to diversity and inclusion, human capital management, data privacy, product safety and human rights. With respect to governance, the independence and diversity of an issuer's board, its compensation practices and board oversight of critical ESG issues are considered as part of the assessment. These factors are weighted based on how material the Adviser believes each factor is to an issuer's financial outlook, and not all factors may be applicable to all issuers. Issuers with an above average ESG rating as determined by the Adviser are considered to have positive ESG characteristics and well-managed ESG risks.
      Investing in debt securities of issuers that the Adviser believes deliver tangible environmental or social impact through core business operations. An assessment of the impact characteristics of an issuer may involve corporate engagement and an analysis of issuer alignment with the United Nations Sustainable Development Goals using qualitative analysis as well as proprietary or third-party data. For example, issuers that provide access to clean water, education, or clean energy through their core business may be considered to deliver tangible impact.
      When evaluating securitized debt securities (including mortgage-backed securities, commercial mortgage-backed securities, and other asset-backed securities), generally considering the issuer's ESG rating along with ESG factors related to the underlying pool of assets, such as energy efficiency and environmental impact of the underlying assets; providing access to affordable housing or opportunities for first time home ownership; and compliance with fair lending laws.
      In addition to its focus on debt securities with positive ESG characteristics, analyzing the credit quality of the issuer, the issuer's potential for success, the credit, currency, and economic risks of the security and its issuer, security-specific features, current and potential future valuation, and trading opportunities to select investments.
      Allocating assets across investment-grade, high yield, and emerging market debt securities. Emerging markets include countries that have an emerging stock market as defined by MSCI, countries or markets with low- to middle-income economies as classified by the World Bank, and other countries or markets that the Adviser identifies as having similar emerging markets characteristics.
      Investing up to 20% of assets in lower-quality debt securities (those of less than investment-grade quality, also referred to as high yield debt securities or junk bonds).
      Managing the fund to have similar overall interest rate risk to the Bloomberg MSCI U.S. Aggregate ESG Choice Bond Index.
      Investing in domestic and foreign issuers.
      Allocating assets across different asset classes, market sectors, and maturities.
      Engaging in transactions that have a leveraging effect on the fund, including investments in derivatives - such as swaps (interest rate, total return, and credit default), options, and futures contracts - and forward-settling securities, to adjust the fund's risk exposure.
      Employing sustainable investing exclusion criteria to avoid investments in issuers that are directly engaged in, and/or derive significant revenue from, certain industries. Please see "Fund Basics - Investment Details - Sustainable Investing Exclusions" for additional information.


   </oef:StrategyNarrativeTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000075889_contentCd_SSU-PRO_RiskMember_SustainabilityRiskMember"
      id="ixv-42584">



      Sustainability Risk.

     Application of Fidelity Management &amp; Research Company LLC's (FMR) (the Adviser) 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 depending on whether certain investments are in or out of favor. The criteria related to the fund's ESG ratings process and/or adherence to its sustainable investing exclusion criteria may result in the fund forgoing opportunities to buy certain securities when it might otherwise be advantageous to do so, or selling securities for ESG reasons when it might be otherwise disadvantageous for it to do so. As a result, the fund's performance may at times be better or worse than the performance of funds that do not use ESG or sustainability criteria. There are significant differences in interpretations of what it means for an issuer to have positive ESG factors. While the Adviser believes its definitions are reasonable, the portfolio decisions it makes may differ with other investors' or advisers' views. When evaluating an issuer, the Adviser is dependent on information or data obtained through voluntary or third-party reporting that may be incomplete, inaccurate, or unavailable, which could cause the Adviser to incorrectly assess an issuer's business practices.

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000075889_contentCd_SSU-PRO_RiskMember_InterestRateChangesMember"
      id="ixv-42593">



      Interest Rate Changes.

     Interest rate increases can cause the price of a debt security to decrease.

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000075889_contentCd_SSU-PRO_RiskMember_ForeignExposureMember"
      id="ixv-42602">



      Foreign Exposure.

     Foreign markets, particularly emerging markets, can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market.
     Foreign exchange rates also can be extremely volatile.

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000075889_contentCd_SSU-PRO_RiskMember_PrepaymentMember"
      id="ixv-42613">



      Prepayment.

     The ability of an issuer of a debt security to repay principal prior to a security's maturity can cause greater price volatility if interest rates change.

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000075889_contentCd_SSU-PRO_RiskMember_IssuerSpecificChangesMember"
      id="ixv-42622">



      Issuer-Specific Changes.

     The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole.
     A decline in the credit quality of an issuer or a provider of credit support (such as guarantees) or a maturity-shortening structure (such as demand and put features) for a security can cause the price of a security to decrease.
     Lower-quality debt securities (those of less than investment-grade quality, also referred to as high yield debt securities or junk bonds) and certain types of other securities involve greater risk of default or price changes due to changes in the credit quality of the issuer. The value of lower-quality debt securities and certain types of other securities can be more volatile due to increased sensitivity to adverse issuer, political, regulatory, market, or economic developments and can be difficult to resell.

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000075889_contentCd_SSU-PRO_RiskMember_LeverageRiskMember"
      id="ixv-42639">



      Leverage Risk.

     Leverage can increase market exposure, magnify investment risks, and cause losses to be realized more quickly.

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000075889_contentCd_SSU-PRO_RiskMember_ManagementRiskMember"
      id="ixv-42648">



      Management Risk.

     The Adviser's application of the fund's strategy criteria may not achieve its intended results. The fund could underperform in comparison to other funds with a similar benchmark or similar objectives and investment strategies .

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000075889_contentCd_SSU-PRO_RiskMember_HighPortfolioTurnoverMember"
      id="ixv-42659">



      High Portfolio Turnover.

     High portfolio turnover (more than 100%) may result in increased transaction costs and potentially higher capital gains or losses. The effects of higher than normal portfolio turnover may adversely affect the fund's performance.



   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000075889_contentCd_SSU-PRO_RiskMember_RiskNotInsuredDepositoryInstitutionMember"
      id="ixv-42669">


     An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency

     .


   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000075889_contentCd_SSU-PRO_RiskMember_RiskLoseMoneyMember"
      id="ixv-42677">


     &#160;

     You could lose money by investing in the fund.


   </oef:RiskTextBlock>
    <oef:BarChartAndPerformanceTableHeading
      contextRef="Pid_S000075889_contentCd_SSU-PRO"
      id="ixv-42686">


     Performance


   </oef:BarChartAndPerformanceTableHeading>
    <oef:PerformanceNarrativeTextBlock
      contextRef="Pid_S000075889_contentCd_SSU-PRO"
      id="ixv-42691">



       The following information is intended to help you understand the risks of investing in the fund.


      The information illustrates the
      changes in the
      performance of the fund's shares


      from year to
       year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time.



     The additional index has characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus.



      Past performance (before and after taxes) is not an indication of future performance.


     Visit



      www.fidelity.com


     for more recent performance information.

   </oef:PerformanceNarrativeTextBlock>
    <oef:PerformanceInformationIllustratesVariabilityOfReturns
      contextRef="Pid_S000075889_contentCd_SSU-PRO"
      id="ixv-42697">

      The information illustrates the
      changes in the
      performance of the fund's shares


      from year to
       year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time.

     </oef:PerformanceInformationIllustratesVariabilityOfReturns>
    <oef:PerformancePastDoesNotIndicateFuture
      contextRef="Pid_S000075889_contentCd_SSU-PRO"
      id="ixv-42709">

      Past performance (before and after taxes) is not an indication of future performance.

     </oef:PerformancePastDoesNotIndicateFuture>
    <oef:PerformanceAvailabilityWebSiteAddress
      contextRef="Pid_S000075889_contentCd_SSU-PRO"
      id="ixv-42715">

      www.fidelity.com
     </oef:PerformanceAvailabilityWebSiteAddress>
    <oef:BarChartHeading
      contextRef="Pid_S000075889_contentCd_SSU-PRO"
      id="ixv-42720">


     Year-by-Year Returns

   </oef:BarChartHeading>
    <oef:AnnlRtrPct
      contextRef="Pid_S000075889_Cid_C000235214_2023"
      decimals="INF"
      id="ixv-101839"
      unitRef="pure">0.0620</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000075889_Cid_C000235214_2024"
      decimals="INF"
      id="ixv-101840"
      unitRef="pure">0.0129</oef:AnnlRtrPct>
    <oef:HighestQuarterlyReturnLabel
      contextRef="Pid_S000075889_contentCd_SSU-PRO"
      id="ixv-42805">
          &#160;&#160;&#160;Highest Quarter Return
        </oef:HighestQuarterlyReturnLabel>
    <oef:BarChartHighestQuarterlyReturn
      contextRef="Pid_S000075889_contentCd_SSU-PRO"
      decimals="4"
      id="ixv-101841"
      unitRef="pure">0.0673</oef:BarChartHighestQuarterlyReturn>
    <oef:BarChartHighestQuarterlyReturnDate
      contextRef="Pid_S000075889_contentCd_SSU-PRO"
      id="ixv-42815">2023-12-31</oef:BarChartHighestQuarterlyReturnDate>
    <oef:LowestQuarterlyReturnLabel
      contextRef="Pid_S000075889_contentCd_SSU-PRO"
      id="ixv-42820">
          &#160;&#160;&#160;Lowest Quarter Return
        </oef:LowestQuarterlyReturnLabel>
    <oef:BarChartLowestQuarterlyReturn
      contextRef="Pid_S000075889_contentCd_SSU-PRO"
      decimals="4"
      id="ixv-101842"
      unitRef="pure">-0.0316</oef:BarChartLowestQuarterlyReturn>
    <oef:BarChartLowestQuarterlyReturnDate
      contextRef="Pid_S000075889_contentCd_SSU-PRO"
      id="ixv-42831">2024-12-31</oef:BarChartLowestQuarterlyReturnDate>
    <oef:YearToDateReturnLabel
      contextRef="Pid_S000075889_contentCd_SSU-PRO"
      id="ixv-42836">
          &#160;&#160;&#160;Year-to-Date Return
        </oef:YearToDateReturnLabel>
    <oef:BarChartYearToDateReturn
      contextRef="Pid_S000075889_contentCd_SSU-PRO"
      decimals="4"
      id="ixv-101843"
      unitRef="pure">0.0626</oef:BarChartYearToDateReturn>
    <oef:BarChartYearToDateReturnDate
      contextRef="Pid_S000075889_contentCd_SSU-PRO"
      id="ixv-42846">2025-09-30</oef:BarChartYearToDateReturnDate>
    <oef:PerformanceTableHeading
      contextRef="Pid_S000075889_contentCd_SSU-PRO"
      id="ixv-42851">


     Average Annual Returns


   </oef:PerformanceTableHeading>
    <oef:PerformanceTableNarrativeTextBlock
      contextRef="Pid_S000075889_contentCd_SSU-PRO"
      id="ixv-42856">




      After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes.



     Actual after-tax returns may differ depending on your individual circumstances.



      The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan).





      Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.




   </oef:PerformanceTableNarrativeTextBlock>
    <oef:PerformanceTableUsesHighestFederalRate
      contextRef="Pid_S000075889_contentCd_SSU-PRO"
      id="ixv-42859">

      After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes.

     </oef:PerformanceTableUsesHighestFederalRate>
    <oef:PerformanceTableNotRelevantToTaxDeferred
      contextRef="Pid_S000075889_contentCd_SSU-PRO"
      id="ixv-42866">

      The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan).

     </oef:PerformanceTableNotRelevantToTaxDeferred>
    <oef:PerformanceTableExplanationAfterTaxHigher
      contextRef="Pid_S000075889_contentCd_SSU-PRO"
      id="ixv-42871">

      Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

     </oef:PerformanceTableExplanationAfterTaxHigher>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000075889_Cid_C000235214_ReturnBeforeTaxes_01"
      id="ixv-42909">
         Return Before Taxes
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000075889_Cid_C000235214_ReturnBeforeTaxes_01"
      decimals="4"
      id="ixv-101844"
      unitRef="pure">0.0129</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000075889_Cid_C000235214_ReturnBeforeTaxes_AverageAnnualReturnSinceInception"
      decimals="4"
      id="footnoteSSU-PROS000075889AAR_A_RBT_loc"
      unitRef="pure">0.0023</oef:AvgAnnlRtrPct>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000075889_Cid_C000235214_AfterTaxesOnDistributions_01"
      id="ixv-42922">
         Return After Taxes on Distributions
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000075889_Cid_C000235214_AfterTaxesOnDistributions_01"
      decimals="4"
      id="ixv-101846"
      unitRef="pure">-0.0033</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000075889_Cid_C000235214_AfterTaxesOnDistributions_AverageAnnualReturnSinceInception"
      decimals="4"
      id="footnoteSSU-PROS000075889AAR_A_ATD_loc"
      unitRef="pure">-0.0128</oef:AvgAnnlRtrPct>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000075889_Cid_C000235214_AfterTaxesOnDistributionsAndSales_01"
      id="ixv-42937">
         Return After Taxes on Distributions and Sale of Fund Shares
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000075889_Cid_C000235214_AfterTaxesOnDistributionsAndSales_01"
      decimals="4"
      id="ixv-101848"
      unitRef="pure">0.0078</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000075889_Cid_C000235214_AfterTaxesOnDistributionsAndSales_AverageAnnualReturnSinceInception"
      decimals="4"
      id="footnoteSSU-PROS000075889AAR_A_ATDS_loc"
      unitRef="pure">-0.0046</oef:AvgAnnlRtrPct>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000075889_Indexid_IXYQV_contentCd_SSU-PRO_01"
      id="ixv-42952">
         Bloomberg MSCI U.S. Aggregate ESG Choice Bond Index
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000075889_Indexid_IXYQV_contentCd_SSU-PRO_01"
      decimals="4"
      id="ixv-101850"
      unitRef="pure">0.0127</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000075889_Indexid_IXYQV_contentCd_SSU-PRO_AverageAnnualReturnSinceInception"
      decimals="4"
      id="ixv-101851"
      unitRef="pure">0.0039</oef:AvgAnnlRtrPct>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000075889_Indexid_LB001_contentCd_SSU-PRO_01"
      id="ixv-42971">
         Bloomberg U.S. Aggregate Bond Index
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000075889_Indexid_LB001_contentCd_SSU-PRO_01"
      decimals="4"
      id="ixv-101852"
      unitRef="pure">0.0125</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000075889_Indexid_LB001_contentCd_SSU-PRO_AverageAnnualReturnSinceInception"
      decimals="4"
      id="ixv-101853"
      unitRef="pure">0.0036</oef:AvgAnnlRtrPct>
    <oef:AnnualReturnInceptionDate contextRef="Pid_S000075889_Cid_C000235214" id="ixv-43003">2022-04-13</oef:AnnualReturnInceptionDate>
    <oef:RiskReturnHeading
      contextRef="Pid_S000090603_contentCd_ECB-PRO"
      id="ixv-44533">


     Fund Summary

     Fund:
     Fidelity&#xae; SAI Enhanced Core Bond Fund

   </oef:RiskReturnHeading>
    <oef:ObjectiveHeading
      contextRef="Pid_S000090603_contentCd_ECB-PRO"
      id="ixv-44542">


     Investment Objective


   </oef:ObjectiveHeading>
    <oef:ObjectivePrimaryTextBlock
      contextRef="Pid_S000090603_contentCd_ECB-PRO"
      id="ixv-44547">


     Fidelity&#xae; SAI Enhanced Core Bond Fund seeks a high level of current income.


   </oef:ObjectivePrimaryTextBlock>
    <oef:ExpenseHeading
      contextRef="Pid_S000090603_contentCd_ECB-PRO"
      id="ixv-44552">


     Fee Table


   </oef:ExpenseHeading>
    <oef:ExpenseNarrativeTextBlock
      contextRef="Pid_S000090603_contentCd_ECB-PRO"
      id="ixv-44558">


     The following table describes the fees and expenses that may be incurred when you buy, hold, and sell shares of the fund.

   </oef:ExpenseNarrativeTextBlock>
    <oef:ShareholderFeesCaption
      contextRef="Pid_S000090603_contentCd_ECB-PRO"
      id="ixv-44568">


     Shareholder fees


   </oef:ShareholderFeesCaption>
    <oef:ShareholderFeeOther
      contextRef="Pid_S000090603_contentCd_ECB-PRO"
      decimals="0"
      id="ixv-101854"
      unitRef="usd">0</oef:ShareholderFeeOther>
    <oef:OperatingExpensesCaption
      contextRef="Pid_S000090603_contentCd_ECB-PRO"
      id="ixv-44583">


     Annual Operating Expenses


   </oef:OperatingExpensesCaption>
    <oef:ManagementFeesOverAssets
      contextRef="Pid_S000090603_Cid_C000257875"
      decimals="6"
      id="ixv-101855"
      unitRef="pure">0.0020</oef:ManagementFeesOverAssets>
    <oef:DistributionAndService12b1FeesOverAssets
      contextRef="Pid_S000090603_Cid_C000257875"
      decimals="6"
      id="ixv-101856"
      unitRef="pure">0</oef:DistributionAndService12b1FeesOverAssets>
    <oef:OtherExpensesOverAssets
      contextRef="Pid_S000090603_Cid_C000257875"
      decimals="6"
      id="footnoteS000090603ECB-PROAOE_AC000257875_OE"
      unitRef="pure">0.0004</oef:OtherExpensesOverAssets>
    <oef:ExpensesOverAssets
      contextRef="Pid_S000090603_Cid_C000257875"
      decimals="6"
      id="ixv-101858"
      unitRef="pure">0.0024</oef:ExpensesOverAssets>
    <oef:FeeWaiverOrReimbursementOverAssets
      contextRef="Pid_S000090603_Cid_C000257875"
      decimals="6"
      id="footnoteS000090603ECB-PROAOE_BC000257875_FW"
      unitRef="pure">-0.0009</oef:FeeWaiverOrReimbursementOverAssets>
    <oef:NetExpensesOverAssets
      contextRef="Pid_S000090603_Cid_C000257875"
      decimals="6"
      id="ixv-101860"
      unitRef="pure">0.0015</oef:NetExpensesOverAssets>
    <oef:OtherExpensesNewFundBasedOnEstimates
      contextRef="Pid_S000090603_contentCd_ECB-PRO"
      id="ixv-44658">

      Based on estimated amounts for the current fiscal year.

     </oef:OtherExpensesNewFundBasedOnEstimates>
    <oef:FeeWaiverOrReimbursementOverAssetsDateOfTermination
      contextRef="Pid_S000090603_contentCd_ECB-PRO"
      id="ixv-44669">2026-12-31</oef:FeeWaiverOrReimbursementOverAssetsDateOfTermination>
    <oef:ExpenseExampleNarrativeTextBlock
      contextRef="Pid_S000090603_contentCd_ECB-PRO"
      id="ixv-44676">


     This
     example

     helps compare the cost of investing in the fund with the cost of investing in other funds.

     Let's say, hypothetically, that the annual return for shares of the fund is 5% and that the fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated:

   </oef:ExpenseExampleNarrativeTextBlock>
    <oef:ExpenseExampleYear01
      contextRef="Pid_S000090603_Cid_C000257875"
      decimals="0"
      id="ixv-101861"
      unitRef="usd">15</oef:ExpenseExampleYear01>
    <oef:ExpenseExampleYear03
      contextRef="Pid_S000090603_Cid_C000257875"
      decimals="0"
      id="ixv-101862"
      unitRef="usd">65</oef:ExpenseExampleYear03>
    <oef:PortfolioTurnoverHeading
      contextRef="Pid_S000090603_contentCd_ECB-PRO"
      id="ixv-44716">


     Portfolio Turnover


   </oef:PortfolioTurnoverHeading>
    <oef:PortfolioTurnoverTextBlock
      contextRef="Pid_S000090603_contentCd_ECB-PRO"
      id="ixv-44721">


     The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. For the period from March 18, 2025 to August 31, 2025, the fund's portfolio turnover rate was



       180


     % of the average value of its portfolio.


   </oef:PortfolioTurnoverTextBlock>
    <oef:PortfolioTurnoverRate
      contextRef="Pid_S000090603_contentCd_ECB-PRO"
      decimals="4"
      id="ixv-101863"
      unitRef="pure">1.80</oef:PortfolioTurnoverRate>
    <oef:StrategyHeading
      contextRef="Pid_S000090603_contentCd_ECB-PRO"
      id="ixv-44730">


     Principal Investment Strategies


   </oef:StrategyHeading>
    <oef:StrategyNarrativeTextBlock
      contextRef="Pid_S000090603_contentCd_ECB-PRO"
      id="ixv-44735">




        Normally investing at least 80% of assets in investment-grade debt securities (those of medium and high quality) of all types and repurchase agreements for those securities.

     Debt securities are used by issuers to borrow money. The issuer usually pays a fixed, variable, or floating rate of interest, and must repay the amount borrowed, usually at the maturity of the security. Debt securities include corporate bonds, government securities (including Treasury securities), repurchase agreements, money market securities, mortgage and other asset-backed securities, loans and loan participations, and other securities, such as hybrids and synthetic securities, believed to have debt-like characteristics (e.g., securities classified as Tier 2 Regulatory capital, securities that rank above share capital in an insolvency waterfall, securities with maturity dates and non-cancellable interest payment structures).&#160;
     Investment grade securities in which the fund invests include securities or issuers rated at least BBB- or its equivalent by at least one nationally recognized statistical ratings organization (NRSRO), or, if unrated, determined by the Adviser to be of comparable quality.
     A repurchase agreement is an agreement to buy a security at one price and a simultaneous agreement to sell it back at an agreed-upon price.
     Effective December 11, 2025, derivative instruments that provide investment exposure to the investments above or exposure to one or more market risk factors associated with such investments are included in the fund's 80% policy, consistent with the fund's investment policies and limitations with respect to investments in derivatives.
     &#160;

      Using the Bloomberg U.S. Aggregate Bond Index as a guide in structuring the fund and selecting its investments as it relates to credit quality distribution and risk characteristics.
      Investing in domestic and foreign issuers.
      Engaging in transactions that have a leveraging effect on the fund, including investments in derivatives - such as swaps (interest rate, total return, and credit default), options, and futures contracts - and forward-settling securities, to adjust the fund's risk exposure.
      Generally utilizing a research-driven approach identifying long-term drivers of debt security returns that may include, but are not limited to, valuation, quality, momentum, and other factors. The research is systematically applied alongside a proprietary portfolio construction and risk management framework to select a broadly diversified group of debt securities that may have the potential to provide a higher total return than that of the Bloomberg U.S. Aggregate Bond Index.


   </oef:StrategyNarrativeTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000090603_contentCd_ECB-PRO_RiskMember_InterestRateChangesMember"
      id="ixv-44764">



      Interest Rate Changes.

     Interest rate increases can cause the price of a debt security to decrease.

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000090603_contentCd_ECB-PRO_RiskMember_ForeignExposureMember"
      id="ixv-44773">



      Foreign Exposure.

     Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market.

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000090603_contentCd_ECB-PRO_RiskMember_PrepaymentMember"
      id="ixv-44782">



      Prepayment.

     The ability of an issuer of a debt security to repay principal prior to a security's maturity can cause greater price volatility if interest rates change.

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000090603_contentCd_ECB-PRO_RiskMember_IssuerSpecificChangesMember"
      id="ixv-44791">



      Issuer-Specific Changes.

     The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole.
     A decline in the credit quality of an issuer or a provider of credit support (such as guarantees) or a maturity-shortening structure (such as demand and put features) for a security can cause the price of a security to decrease.
     Lower-quality debt securities (those of less than investment-grade quality, also referred to as high yield debt securities or junk bonds) and certain types of other securities involve greater risk of default or price changes due to changes in the credit quality of the issuer. The value of lower-quality debt securities and certain types of other securities can be more volatile due to increased sensitivity to adverse issuer, political, regulatory, market, or economic developments and can be difficult to resell.

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000090603_contentCd_ECB-PRO_RiskMember_LeverageRiskMember"
      id="ixv-44804">



      Leverage Risk.

     Leverage can increase market exposure, magnify investment risks, and cause losses to be realized more quickly.

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000090603_contentCd_ECB-PRO_RiskMember_QuantitativeInvestingMember"
      id="ixv-44813">



      Quantitative Investing.

     Securities selected using quantitative analysis can perform differently from the market as a whole as a result of the factors used in the analysis, the weight placed on each factor, and changes in the factors' historical trends.

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000090603_contentCd_ECB-PRO_RiskMember_HighPortfolioTurnoverMember"
      id="ixv-44822">




        High Portfolio Turnover.

     High portfolio turnover (more than 100%) may result in increased transaction costs and potentially higher capital gains or losses. The effects of higher than normal portfolio turnover may adversely affect the fund's performance.

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000090603_contentCd_ECB-PRO_RiskMember_RiskNotInsuredDepositoryInstitutionMember"
      id="ixv-44832">


     An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency

     .


   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000090603_contentCd_ECB-PRO_RiskMember_RiskLoseMoneyMember"
      id="ixv-44840">


     &#160;

     You could lose money by investing in the fund.


   </oef:RiskTextBlock>
    <oef:BarChartAndPerformanceTableHeading
      contextRef="Pid_S000090603_contentCd_ECB-PRO"
      id="ixv-44849">


     Performance


   </oef:BarChartAndPerformanceTableHeading>
    <oef:PerformanceNarrativeTextBlock
      contextRef="Pid_S000090603_contentCd_ECB-PRO"
      id="ixv-44854">






      Performance history will be available for the fund after the fund has been in operation for one calendar year.



   </oef:PerformanceNarrativeTextBlock>
    <oef:PerformanceOneYearOrLess
      contextRef="Pid_S000090603_contentCd_ECB-PRO"
      id="ixv-44858">

      Performance history will be available for the fund after the fund has been in operation for one calendar year.

     </oef:PerformanceOneYearOrLess>
    <link:footnoteLink
      xlink:role="http://www.xbrl.org/2003/role/link"
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        <link:footnote id="footnoteASTP-PROS000007007SHF_A" xlink:label="footnoteASTP-PROS000007007SHF_A" xlink:role="http://www.xbrl.org/2003/role/footnote" xlink:type="resource" xml:lang="en-US"><xhtml:div style="padding:2px"><xhtml:span> </xhtml:span><xhtml:span style="font-family:Arial; font-size:4.67pt; vertical-align:super">A</xhtml:span><xhtml:span> </xhtml:span><xhtml:span> </xhtml:span><xhtml:span style="font-family:Arial; font-size:8.5pt">Purchases of $250,000 or more will not be subject to a front-end sales charge, but may be subject to a 0.50% contingent deferred sales charge (CDSC) if the intermediary firm has elected an upfront finder's fee at the time the shares are purchased, or a 0.75% CDSC if the shares purchased are recordkept in a Fidelity Advisor</xhtml:span><xhtml:span> </xhtml:span><xhtml:span style="font-family:Arial; font-size:7pt">&#xae; </xhtml:span><xhtml:span style="font-family:Arial; font-size:8.5pt">401(k) Retirement Plan.</xhtml:span><xhtml:span> </xhtml:span><xhtml:span> </xhtml:span></xhtml:div></link:footnote>
        <link:footnoteArc
          xlink:arcrole="http://www.xbrl.org/2003/arcrole/fact-footnote"
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        <link:loc
          xlink:href="#footnoteASTP-PROS000007007SHF_BC000171438"
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        <link:footnote id="footnoteASTP-PROS000007007SHF_B" xlink:label="footnoteASTP-PROS000007007SHF_B" xlink:role="http://www.xbrl.org/2003/role/footnote" xlink:type="resource" xml:lang="en-US"><xhtml:div style="padding:2px"><xhtml:span> </xhtml:span><xhtml:span style="font-family:Arial; font-size:4.67pt; vertical-align:super">B</xhtml:span><xhtml:span> </xhtml:span><xhtml:span> </xhtml:span><xhtml:span style="font-family:Arial; font-size:8.5pt">Purchases of $250,000 or more will not be subject to a front-end sales charge but may be subject to a 0.25% CDSC if a finder's fee is paid at the time the shares are purchased.</xhtml:span><xhtml:span> </xhtml:span><xhtml:span> </xhtml:span></xhtml:div></link:footnote>
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          xlink:arcrole="http://www.xbrl.org/2003/arcrole/fact-footnote"
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        <link:loc
          xlink:href="#footnoteASTP-PROS000007007SHF_CC000171439"
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        <link:footnote id="footnoteASTP-PROS000007007SHF_C" xlink:label="footnoteASTP-PROS000007007SHF_C" xlink:role="http://www.xbrl.org/2003/role/footnote" xlink:type="resource" xml:lang="en-US"><xhtml:div style="padding:2px"><xhtml:span> </xhtml:span><xhtml:span style="font-family:Arial; font-size:4.67pt; vertical-align:super">C</xhtml:span><xhtml:span> </xhtml:span><xhtml:span> </xhtml:span><xhtml:span style="font-family:Arial; font-size:8.5pt">On Class C shares redeemed less than one year after purchase.</xhtml:span><xhtml:span> </xhtml:span><xhtml:span> </xhtml:span></xhtml:div></link:footnote>
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          xlink:arcrole="http://www.xbrl.org/2003/arcrole/fact-footnote"
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        <link:loc
          xlink:href="#footnoteS000007007ASTP-PROAOE_AC000171440_FW"
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          xlink:type="locator"/>
        <link:footnote id="footnoteS000007007ASTP-PROAOE_A" xlink:label="footnoteS000007007ASTP-PROAOE_A" xlink:role="http://www.xbrl.org/2003/role/footnote" xlink:type="resource" xml:lang="en-US"><xhtml:div style="padding:2px"><xhtml:span> </xhtml:span><xhtml:span style="font-family:Arial; font-size:4.67pt; vertical-align:super">A</xhtml:span><xhtml:span> </xhtml:span><xhtml:span style="font-family:Arial; font-size:8.5pt">Fidelity Management &amp; Research Company LLC (FMR) has contractually agreed to reimburse Class I of the fund to the extent that total operating expenses (excluding interest, certain taxes, fees and expenses of the Independent Trustees, proxy and shareholder meeting expenses, extraordinary expenses, and acquired fund fees and expenses (including fees and expenses associated with a wholly owned subsidiary), if any, as well as non-operating expenses such as brokerage commissions and fees and expenses associated with the fund's securities lending program, if applicable), as a percentage of its average net assets, exceed 0.30% (the Expense Cap). If at any time during the current fiscal year expenses for Class I of the fund fall below the Expense Cap, FMR reserves the right to recoup through the end of the fiscal year any expenses that were reimbursed during the current fiscal year up to, but not in excess of, the Expense Cap. This arrangement will remain in effect through </xhtml:span><xhtml:span> </xhtml:span><xhtml:span style="font-family:Arial; font-size:8.5pt">December 31, </xhtml:span><xhtml:span class="delClass" style="color:#ff0000; display:none;">
       </xhtml:span><xhtml:span
      class="redlineClass"
      style="font-family:Arial; font-size:8.5pt; ">2026</xhtml:span><xhtml:span> </xhtml:span><xhtml:span> </xhtml:span><xhtml:span style="font-family:Arial; font-size:8.5pt">. FMR may not terminate this arrangement before the expiration date without the approval of the Board of Trustees and may extend it</xhtml:span><xhtml:span> </xhtml:span><xhtml:span style="font-family:Arial; font-size:8.5pt">in its discretion after that date.</xhtml:span><xhtml:span> </xhtml:span></xhtml:div></link:footnote>
        <link:footnoteArc
          xlink:arcrole="http://www.xbrl.org/2003/arcrole/fact-footnote"
          xlink:from="footnoteS000007007ASTP-PROAOE_AC000171440_FW"
          xlink:to="footnoteS000007007ASTP-PROAOE_A"
          xlink:type="arc"/>
        <link:loc
          xlink:href="#footnoteASTP-PROS000007007AAR_A_RBT_loc"
          xlink:label="footnoteASTP-PROS000007007AAR_A_RBT_loc"
          xlink:type="locator"/>
        <link:footnote id="footnoteASTP-PROS000007007AAR_A" xlink:label="footnoteASTP-PROS000007007AAR_A" xlink:role="http://www.xbrl.org/2003/role/footnote" xlink:type="resource" xml:lang="en-US"><xhtml:div style="padding:2px"><xhtml:span> </xhtml:span><xhtml:span
      class="redlineClass"
      style="font-family:Arial; font-size:4.5pt; vertical-align:3pt; ">A</xhtml:span><xhtml:span> </xhtml:span><xhtml:span
      class="redlineClass"
      style="font-family:Arial; font-size:8.5pt; font-style:italic; ">From </xhtml:span><xhtml:span> </xhtml:span><xhtml:span
      class="redlineClass"
      style="font-family:Arial; font-size:8.5pt; font-style:italic; ">July 12, 2016</xhtml:span><xhtml:span> </xhtml:span><xhtml:span> </xhtml:span><xhtml:span
      class="redlineClass"
      style="font-family:Arial; font-size:8.5pt; font-style:italic; ">.</xhtml:span><xhtml:span> </xhtml:span></xhtml:div></link:footnote>
        <link:footnoteArc
          xlink:arcrole="http://www.xbrl.org/2003/arcrole/fact-footnote"
          xlink:from="footnoteASTP-PROS000007007AAR_A_RBT_loc"
          xlink:to="footnoteASTP-PROS000007007AAR_A"
          xlink:type="arc"/>
        <link:loc
          xlink:href="#footnoteASTP-PROS000007007AAR_A_ATD_loc"
          xlink:label="footnoteASTP-PROS000007007AAR_A_ATD_loc"
          xlink:type="locator"/>
        <link:footnoteArc
          xlink:arcrole="http://www.xbrl.org/2003/arcrole/fact-footnote"
          xlink:from="footnoteASTP-PROS000007007AAR_A_ATD_loc"
          xlink:to="footnoteASTP-PROS000007007AAR_A"
          xlink:type="arc"/>
        <link:loc
          xlink:href="#footnoteASTP-PROS000007007AAR_A_ATDS_loc"
          xlink:label="footnoteASTP-PROS000007007AAR_A_ATDS_loc"
          xlink:type="locator"/>
        <link:footnoteArc
          xlink:arcrole="http://www.xbrl.org/2003/arcrole/fact-footnote"
          xlink:from="footnoteASTP-PROS000007007AAR_A_ATDS_loc"
          xlink:to="footnoteASTP-PROS000007007AAR_A"
          xlink:type="arc"/>
        <link:loc
          xlink:href="#footnoteASTP-PROS000007007AAR_B_RBT_loc"
          xlink:label="footnoteASTP-PROS000007007AAR_B_RBT_loc"
          xlink:type="locator"/>
        <link:footnote id="footnoteASTP-PROS000007007AAR_B" xlink:label="footnoteASTP-PROS000007007AAR_B" xlink:role="http://www.xbrl.org/2003/role/footnote" xlink:type="resource" xml:lang="en-US"><xhtml:div style="padding:2px"><xhtml:span> </xhtml:span><xhtml:span
      class="redlineClass"
      style="font-family:Arial; font-size:4.5pt; vertical-align:3pt; ">B</xhtml:span><xhtml:span> </xhtml:span><xhtml:span
      class="redlineClass"
      style="font-family:Arial; font-size:8.5pt; font-style:italic; ">From </xhtml:span><xhtml:span> </xhtml:span><xhtml:span
      class="redlineClass"
      style="font-family:Arial; font-size:8.5pt; font-style:italic; ">July 12, 2016</xhtml:span><xhtml:span> </xhtml:span><xhtml:span> </xhtml:span><xhtml:span
      class="redlineClass"
      style="font-family:Arial; font-size:8.5pt; font-style:italic; ">.</xhtml:span><xhtml:span> </xhtml:span></xhtml:div></link:footnote>
        <link:footnoteArc
          xlink:arcrole="http://www.xbrl.org/2003/arcrole/fact-footnote"
          xlink:from="footnoteASTP-PROS000007007AAR_B_RBT_loc"
          xlink:to="footnoteASTP-PROS000007007AAR_B"
          xlink:type="arc"/>
        <link:loc
          xlink:href="#footnoteASTP-PROS000007007AAR_C_RBT_loc"
          xlink:label="footnoteASTP-PROS000007007AAR_C_RBT_loc"
          xlink:type="locator"/>
        <link:footnote id="footnoteASTP-PROS000007007AAR_C" xlink:label="footnoteASTP-PROS000007007AAR_C" xlink:role="http://www.xbrl.org/2003/role/footnote" xlink:type="resource" xml:lang="en-US"><xhtml:div style="padding:2px"><xhtml:span> </xhtml:span><xhtml:span
      class="redlineClass"
      style="font-family:Arial; font-size:4.5pt; vertical-align:3pt; ">C</xhtml:span><xhtml:span> </xhtml:span><xhtml:span
      class="redlineClass"
      style="font-family:Arial; font-size:8.5pt; font-style:italic; ">From </xhtml:span><xhtml:span> </xhtml:span><xhtml:span
      class="redlineClass"
      style="font-family:Arial; font-size:8.5pt; font-style:italic; ">July 12, 2016</xhtml:span><xhtml:span> </xhtml:span><xhtml:span> </xhtml:span><xhtml:span
      class="redlineClass"
      style="font-family:Arial; font-size:8.5pt; font-style:italic; ">.</xhtml:span><xhtml:span> </xhtml:span></xhtml:div></link:footnote>
        <link:footnoteArc
          xlink:arcrole="http://www.xbrl.org/2003/arcrole/fact-footnote"
          xlink:from="footnoteASTP-PROS000007007AAR_C_RBT_loc"
          xlink:to="footnoteASTP-PROS000007007AAR_C"
          xlink:type="arc"/>
        <link:loc
          xlink:href="#footnoteASTP-PROS000007007AAR_D_RBT_loc"
          xlink:label="footnoteASTP-PROS000007007AAR_D_RBT_loc"
          xlink:type="locator"/>
        <link:footnote id="footnoteASTP-PROS000007007AAR_D" xlink:label="footnoteASTP-PROS000007007AAR_D" xlink:role="http://www.xbrl.org/2003/role/footnote" xlink:type="resource" xml:lang="en-US"><xhtml:div style="padding:2px"><xhtml:span> </xhtml:span><xhtml:span
      class="redlineClass"
      style="font-family:Arial; font-size:4.5pt; vertical-align:3pt; ">D</xhtml:span><xhtml:span> </xhtml:span><xhtml:span
      class="redlineClass"
      style="font-family:Arial; font-size:8.5pt; font-style:italic; ">From </xhtml:span><xhtml:span> </xhtml:span><xhtml:span
      class="redlineClass"
      style="font-family:Arial; font-size:8.5pt; font-style:italic; ">July 12, 2016</xhtml:span><xhtml:span> </xhtml:span><xhtml:span> </xhtml:span><xhtml:span
      class="redlineClass"
      style="font-family:Arial; font-size:8.5pt; font-style:italic; ">.</xhtml:span><xhtml:span> </xhtml:span></xhtml:div></link:footnote>
        <link:footnoteArc
          xlink:arcrole="http://www.xbrl.org/2003/arcrole/fact-footnote"
          xlink:from="footnoteASTP-PROS000007007AAR_D_RBT_loc"
          xlink:to="footnoteASTP-PROS000007007AAR_D"
          xlink:type="arc"/>
        <link:loc
          xlink:href="#footnoteASTP-PROS000007007AAR_E_RBT_loc"
          xlink:label="footnoteASTP-PROS000007007AAR_E_RBT_loc"
          xlink:type="locator"/>
        <link:footnote id="footnoteASTP-PROS000007007AAR_E" xlink:label="footnoteASTP-PROS000007007AAR_E" xlink:role="http://www.xbrl.org/2003/role/footnote" xlink:type="resource" xml:lang="en-US"><xhtml:div style="padding:2px"><xhtml:span> </xhtml:span><xhtml:span
      class="redlineClass"
      style="font-family:Arial; font-size:4.5pt; vertical-align:3pt; ">E</xhtml:span><xhtml:span> </xhtml:span><xhtml:span
      class="redlineClass"
      style="font-family:Arial; font-size:8.5pt; font-style:italic; ">From </xhtml:span><xhtml:span> </xhtml:span><xhtml:span
      class="redlineClass"
      style="font-family:Arial; font-size:8.5pt; font-style:italic; ">October 2, 2018</xhtml:span><xhtml:span> </xhtml:span><xhtml:span> </xhtml:span><xhtml:span
      class="redlineClass"
      style="font-family:Arial; font-size:8.5pt; font-style:italic; ">.</xhtml:span><xhtml:span> </xhtml:span></xhtml:div></link:footnote>
        <link:footnoteArc
          xlink:arcrole="http://www.xbrl.org/2003/arcrole/fact-footnote"
          xlink:from="footnoteASTP-PROS000007007AAR_E_RBT_loc"
          xlink:to="footnoteASTP-PROS000007007AAR_E"
          xlink:type="arc"/>
        <link:loc
          xlink:href="#footnoteSTB-PROS000062237AAR_A_RBT_loc"
          xlink:label="footnoteSTB-PROS000062237AAR_A_RBT_loc"
          xlink:type="locator"/>
        <link:footnote id="footnoteSTB-PROS000062237AAR_A" xlink:label="footnoteSTB-PROS000062237AAR_A" xlink:role="http://www.xbrl.org/2003/role/footnote" xlink:type="resource" xml:lang="en-US"><xhtml:div style="padding:2px"><xhtml:span> </xhtml:span><xhtml:span style="font-family:Arial; font-size:4.67pt; vertical-align:super">A</xhtml:span><xhtml:span> </xhtml:span><xhtml:span style="font-family:Arial; font-size:8.5pt; font-style:italic">From </xhtml:span><xhtml:span> </xhtml:span><xhtml:span style="font-family:Arial; font-size:8.5pt; font-style:italic">October 25, 2018</xhtml:span><xhtml:span> </xhtml:span><xhtml:span> </xhtml:span><xhtml:span style="font-family:Arial; font-size:8.5pt; font-style:italic">.</xhtml:span><xhtml:span> </xhtml:span></xhtml:div></link:footnote>
        <link:footnoteArc
          xlink:arcrole="http://www.xbrl.org/2003/arcrole/fact-footnote"
          xlink:from="footnoteSTB-PROS000062237AAR_A_RBT_loc"
          xlink:to="footnoteSTB-PROS000062237AAR_A"
          xlink:type="arc"/>
        <link:loc
          xlink:href="#footnoteSTB-PROS000062237AAR_A_ATD_loc"
          xlink:label="footnoteSTB-PROS000062237AAR_A_ATD_loc"
          xlink:type="locator"/>
        <link:footnoteArc
          xlink:arcrole="http://www.xbrl.org/2003/arcrole/fact-footnote"
          xlink:from="footnoteSTB-PROS000062237AAR_A_ATD_loc"
          xlink:to="footnoteSTB-PROS000062237AAR_A"
          xlink:type="arc"/>
        <link:loc
          xlink:href="#footnoteSTB-PROS000062237AAR_A_ATDS_loc"
          xlink:label="footnoteSTB-PROS000062237AAR_A_ATDS_loc"
          xlink:type="locator"/>
        <link:footnoteArc
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          xlink:from="footnoteSTB-PROS000062237AAR_A_ATDS_loc"
          xlink:to="footnoteSTB-PROS000062237AAR_A"
          xlink:type="arc"/>
        <link:loc
          xlink:href="#footnoteAIGB-PROS000007004SHF_AC000019121"
          xlink:label="footnoteAIGB-PROS000007004SHF_AC000019121"
          xlink:type="locator"/>
        <link:footnote id="footnoteAIGB-PROS000007004SHF_A" xlink:label="footnoteAIGB-PROS000007004SHF_A" xlink:role="http://www.xbrl.org/2003/role/footnote" xlink:type="resource" xml:lang="en-US"><xhtml:div style="padding:2px"><xhtml:span> </xhtml:span><xhtml:span style="font-family:Arial; font-size:4.67pt; vertical-align:super">A</xhtml:span><xhtml:span> </xhtml:span><xhtml:span> </xhtml:span><xhtml:span style="font-family:Arial; font-size:8.5pt">Class A and Class M purchases of $1 million or more will not be subject to a front-end sales charge. Such Class A and Class M purchases may be subject, upon redemption, to a contingent deferred sales charge (CDSC) of 0.75% and 0.25%, respectively.</xhtml:span><xhtml:span> </xhtml:span><xhtml:span> </xhtml:span></xhtml:div></link:footnote>
        <link:footnoteArc
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          xlink:type="arc"/>
        <link:loc
          xlink:href="#footnoteAIGB-PROS000007004SHF_AC000019124"
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        <link:footnoteArc
          xlink:arcrole="http://www.xbrl.org/2003/arcrole/fact-footnote"
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        <link:loc
          xlink:href="#footnoteAIGB-PROS000007004SHF_BC000019123"
          xlink:label="footnoteAIGB-PROS000007004SHF_BC000019123"
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        <link:footnote id="footnoteAIGB-PROS000007004SHF_B" xlink:label="footnoteAIGB-PROS000007004SHF_B" xlink:role="http://www.xbrl.org/2003/role/footnote" xlink:type="resource" xml:lang="en-US"><xhtml:div style="padding:2px"><xhtml:span> </xhtml:span><xhtml:span style="font-family:Arial; font-size:4.67pt; vertical-align:super">B</xhtml:span><xhtml:span> </xhtml:span><xhtml:span> </xhtml:span><xhtml:span style="font-family:Arial; font-size:8.5pt">On Class C shares redeemed less than one year after purchase.</xhtml:span><xhtml:span> </xhtml:span><xhtml:span> </xhtml:span></xhtml:div></link:footnote>
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          xlink:from="footnoteAIGB-PROS000007004SHF_BC000019123"
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        <link:loc
          xlink:href="#footnoteS000007004AIGB-PROAOE_AC000205019_FW"
          xlink:label="footnoteS000007004AIGB-PROAOE_AC000205019_FW"
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        <link:footnote id="footnoteS000007004AIGB-PROAOE_A" xlink:label="footnoteS000007004AIGB-PROAOE_A" xlink:role="http://www.xbrl.org/2003/role/footnote" xlink:type="resource" xml:lang="en-US"><xhtml:div style="padding:2px"><xhtml:span> </xhtml:span><xhtml:span class="delClass" style="color:#ff0000; display:none;">
      </xhtml:span><xhtml:span
      class="redlineClass"
      style="font-family:Arial; font-size:4.5pt; vertical-align:3pt; ">A</xhtml:span><xhtml:span> </xhtml:span><xhtml:span style="font-family:Arial; font-size:8.5pt">Fidelity Management &amp; Research Company LLC (FMR) has contractually agreed to reimburse Class Z of the fund to the extent that total operating expenses (excluding interest, certain taxes, fees and expenses of the Independent Trustees, extraordinary expenses, and acquired fund fees and expenses (including fees and expenses associated with a wholly owned subsidiary), if any, as well as non-operating expenses such as brokerage commissions and fees and expenses associated with the fund's securities lending program, if applicable), as a percentage of its average net assets, exceed 0.36% (the Expense Cap). If at any time during the current fiscal year expenses for Class Z of the fund fall below the Expense Cap, FMR reserves the right to recoup through the end of the fiscal year any expenses that were reimbursed during the current fiscal year up to, but not in excess of, the Expense Cap. This arrangement will remain in effect through </xhtml:span><xhtml:span> </xhtml:span><xhtml:span style="font-family:Arial; font-size:8.5pt">December 31, </xhtml:span><xhtml:span class="delClass" style="color:#ff0000; display:none;">
       </xhtml:span><xhtml:span
      class="redlineClass"
      style="font-family:Arial; font-size:8.5pt; ">2026</xhtml:span><xhtml:span> </xhtml:span><xhtml:span> </xhtml:span><xhtml:span style="font-family:Arial; font-size:8.5pt">. FMR may not terminate this arrangement before the expiration date without the approval of the Board of Trustees and may extend it in its discretion after that date.</xhtml:span><xhtml:span> </xhtml:span></xhtml:div></link:footnote>
        <link:footnoteArc
          xlink:arcrole="http://www.xbrl.org/2003/arcrole/fact-footnote"
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        <link:loc
          xlink:href="#footnoteAIGB-PROS000007004AAR_A_RBT_loc"
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        <link:footnote id="footnoteAIGB-PROS000007004AAR_A" xlink:label="footnoteAIGB-PROS000007004AAR_A" xlink:role="http://www.xbrl.org/2003/role/footnote" xlink:type="resource" xml:lang="en-US"><xhtml:div style="padding:2px"><xhtml:span> </xhtml:span><xhtml:span
      class="redlineClass"
      style="font-family:Arial; font-size:4.5pt; vertical-align:3pt; ">A</xhtml:span><xhtml:span> </xhtml:span><xhtml:span
      class="redlineClass"
      style="font-family:Arial; font-size:8.5pt; font-style:italic; ">From </xhtml:span><xhtml:span> </xhtml:span><xhtml:span
      class="redlineClass"
      style="font-family:Arial; font-size:8.5pt; font-style:italic; ">October 2, 2018</xhtml:span><xhtml:span> </xhtml:span><xhtml:span> </xhtml:span><xhtml:span
      class="redlineClass"
      style="font-family:Arial; font-size:8.5pt; font-style:italic; ">.</xhtml:span><xhtml:span> </xhtml:span></xhtml:div></link:footnote>
        <link:footnoteArc
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          xlink:from="footnoteAIGB-PROS000007004AAR_A_RBT_loc"
          xlink:to="footnoteAIGB-PROS000007004AAR_A"
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        <link:loc
          xlink:href="#footnoteS000062001ZCI-PROAOE_AC000200823_TE"
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          xlink:type="locator"/>
        <link:footnote id="footnoteS000062001ZCI-PROAOE_A" xlink:label="footnoteS000062001ZCI-PROAOE_A" xlink:role="http://www.xbrl.org/2003/role/footnote" xlink:type="resource" xml:lang="en-US"><xhtml:div style="padding:2px"><xhtml:span> </xhtml:span><xhtml:span style="font-family:Arial; font-size:4.67pt; vertical-align:super">A</xhtml:span><xhtml:span> </xhtml:span><xhtml:span style="font-family:Arial; font-size:8.5pt; font-style:italic">The fund is available only to certain fee-based accounts and advisory programs offered by Fidelity. Advisory account clients, retirement plans, plan sponsors and/or plan participants typically pay an advisory fee that generally covers investment advisory and administrative services.</xhtml:span><xhtml:span> </xhtml:span></xhtml:div></link:footnote>
        <link:footnoteArc
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          xlink:from="footnoteS000062001ZCI-PROAOE_AC000200823_TE"
          xlink:to="footnoteS000062001ZCI-PROAOE_A"
          xlink:type="arc"/>
        <link:loc
          xlink:href="#footnoteZCI-PROS000062001AAR_A_RBT_loc"
          xlink:label="footnoteZCI-PROS000062001AAR_A_RBT_loc"
          xlink:type="locator"/>
        <link:footnote id="footnoteZCI-PROS000062001AAR_A" xlink:label="footnoteZCI-PROS000062001AAR_A" xlink:role="http://www.xbrl.org/2003/role/footnote" xlink:type="resource" xml:lang="en-US"><xhtml:div style="padding:2px"><xhtml:span> </xhtml:span><xhtml:span style="font-family:Arial; font-size:4.67pt; vertical-align:super">A</xhtml:span><xhtml:span> </xhtml:span><xhtml:span style="font-family:Arial; font-size:8.5pt; font-style:italic">From </xhtml:span><xhtml:span> </xhtml:span><xhtml:span style="font-family:Arial; font-size:8.5pt; font-style:italic">May 31, 2018</xhtml:span><xhtml:span> </xhtml:span><xhtml:span> </xhtml:span><xhtml:span style="font-family:Arial; font-size:8.5pt; font-style:italic">.</xhtml:span><xhtml:span> </xhtml:span></xhtml:div></link:footnote>
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          xlink:from="footnoteZCI-PROS000062001AAR_A_RBT_loc"
          xlink:to="footnoteZCI-PROS000062001AAR_A"
          xlink:type="arc"/>
        <link:loc
          xlink:href="#footnoteZCI-PROS000062001AAR_A_ATD_loc"
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          xlink:type="locator"/>
        <link:footnoteArc
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          xlink:to="footnoteZCI-PROS000062001AAR_A"
          xlink:type="arc"/>
        <link:loc
          xlink:href="#footnoteZCI-PROS000062001AAR_A_ATDS_loc"
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          xlink:type="locator"/>
        <link:footnoteArc
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          xlink:type="arc"/>
        <link:loc
          xlink:href="#footnoteS000069440SST-LDI-PROAOE_AC000221555_FW"
          xlink:label="footnoteS000069440SST-LDI-PROAOE_AC000221555_FW"
          xlink:type="locator"/>
        <link:footnote id="footnoteS000069440SST-LDI-PROAOE_A" xlink:label="footnoteS000069440SST-LDI-PROAOE_A" xlink:role="http://www.xbrl.org/2003/role/footnote" xlink:type="resource" xml:lang="en-US"><xhtml:div style="padding:2px"><xhtml:span> </xhtml:span><xhtml:span style="font-family:Arial; font-size:4.67pt; vertical-align:super">A</xhtml:span><xhtml:span> </xhtml:span><xhtml:span style="font-family:Arial; font-size:8.5pt">Fidelity Management &amp; Research Company LLC (FMR) has contractually agreed to reimburse the fund to the extent that total operating expenses (excluding interest, certain taxes, fees and expenses of the Independent Trustees, proxy and shareholder meeting expenses, extraordinary expenses, and acquired fund fees and expenses (including fees and expenses associated with a wholly owned subsidiary), if any, as well as non-operating expenses such as brokerage commissions and fees and expenses associated with the fund's securities lending program, if applicable), as a percentage of its average net assets, exceed 0.20% (the Expense Cap). If at any time during the current fiscal year expenses for the fund fall below the Expense Cap, FMR reserves the right to recoup through the end of the fiscal year any expenses that were reimbursed during the current fiscal year up to, but not in excess of, the Expense Cap. This arrangement will remain in effect through </xhtml:span><xhtml:span> </xhtml:span><xhtml:span style="font-family:Arial; font-size:8.5pt">December 31, </xhtml:span><xhtml:span class="delClass" style="color:#ff0000; display:none;">
       </xhtml:span><xhtml:span
      class="redlineClass"
      style="font-family:Arial; font-size:8.5pt; ">2026</xhtml:span><xhtml:span> </xhtml:span><xhtml:span> </xhtml:span><xhtml:span style="font-family:Arial; font-size:8.5pt">. FMR may not terminate this arrangement before the expiration date without the approval of the Board of Trustees and may extend it in its discretion after that date.</xhtml:span><xhtml:span> </xhtml:span></xhtml:div></link:footnote>
        <link:footnoteArc
          xlink:arcrole="http://www.xbrl.org/2003/arcrole/fact-footnote"
          xlink:from="footnoteS000069440SST-LDI-PROAOE_AC000221555_FW"
          xlink:to="footnoteS000069440SST-LDI-PROAOE_A"
          xlink:type="arc"/>
        <link:loc
          xlink:href="#footnoteSST-LDI-PROS000069440AAR_A_RBT_loc"
          xlink:label="footnoteSST-LDI-PROS000069440AAR_A_RBT_loc"
          xlink:type="locator"/>
        <link:footnote id="footnoteSST-LDI-PROS000069440AAR_A" xlink:label="footnoteSST-LDI-PROS000069440AAR_A" xlink:role="http://www.xbrl.org/2003/role/footnote" xlink:type="resource" xml:lang="en-US"><xhtml:div style="padding:2px"><xhtml:span> </xhtml:span><xhtml:span style="font-family:Arial; font-size:4.67pt; vertical-align:super">A</xhtml:span><xhtml:span> </xhtml:span><xhtml:span style="font-family:Arial; font-size:8.5pt; font-style:italic">From </xhtml:span><xhtml:span> </xhtml:span><xhtml:span style="font-family:Arial; font-size:8.5pt; font-style:italic">September 15, 2020</xhtml:span><xhtml:span> </xhtml:span><xhtml:span> </xhtml:span><xhtml:span style="font-family:Arial; font-size:8.5pt; font-style:italic">.</xhtml:span><xhtml:span> </xhtml:span></xhtml:div></link:footnote>
        <link:footnoteArc
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          xlink:from="footnoteSST-LDI-PROS000069440AAR_A_RBT_loc"
          xlink:to="footnoteSST-LDI-PROS000069440AAR_A"
          xlink:type="arc"/>
        <link:loc
          xlink:href="#footnoteSST-LDI-PROS000069440AAR_A_ATD_loc"
          xlink:label="footnoteSST-LDI-PROS000069440AAR_A_ATD_loc"
          xlink:type="locator"/>
        <link:footnoteArc
          xlink:arcrole="http://www.xbrl.org/2003/arcrole/fact-footnote"
          xlink:from="footnoteSST-LDI-PROS000069440AAR_A_ATD_loc"
          xlink:to="footnoteSST-LDI-PROS000069440AAR_A"
          xlink:type="arc"/>
        <link:loc
          xlink:href="#footnoteSST-LDI-PROS000069440AAR_A_ATDS_loc"
          xlink:label="footnoteSST-LDI-PROS000069440AAR_A_ATDS_loc"
          xlink:type="locator"/>
        <link:footnoteArc
          xlink:arcrole="http://www.xbrl.org/2003/arcrole/fact-footnote"
          xlink:from="footnoteSST-LDI-PROS000069440AAR_A_ATDS_loc"
          xlink:to="footnoteSST-LDI-PROS000069440AAR_A"
          xlink:type="arc"/>
        <link:loc
          xlink:href="#footnoteSST-LDI-PROS000069441AAR_A_RBT_loc"
          xlink:label="footnoteSST-LDI-PROS000069441AAR_A_RBT_loc"
          xlink:type="locator"/>
        <link:footnote id="footnoteSST-LDI-PROS000069441AAR_A" xlink:label="footnoteSST-LDI-PROS000069441AAR_A" xlink:role="http://www.xbrl.org/2003/role/footnote" xlink:type="resource" xml:lang="en-US"><xhtml:div style="padding:2px"><xhtml:span> </xhtml:span><xhtml:span style="font-family:Arial; font-size:4.67pt; vertical-align:super">A</xhtml:span><xhtml:span> </xhtml:span><xhtml:span style="font-family:Arial; font-size:8.5pt; font-style:italic">From </xhtml:span><xhtml:span> </xhtml:span><xhtml:span style="font-family:Arial; font-size:8.5pt; font-style:italic">September 15, 2020</xhtml:span><xhtml:span> </xhtml:span><xhtml:span> </xhtml:span><xhtml:span style="font-family:Arial; font-size:8.5pt; font-style:italic">.</xhtml:span><xhtml:span> </xhtml:span></xhtml:div></link:footnote>
        <link:footnoteArc
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          xlink:from="footnoteSST-LDI-PROS000069441AAR_A_RBT_loc"
          xlink:to="footnoteSST-LDI-PROS000069441AAR_A"
          xlink:type="arc"/>
        <link:loc
          xlink:href="#footnoteSST-LDI-PROS000069441AAR_A_ATD_loc"
          xlink:label="footnoteSST-LDI-PROS000069441AAR_A_ATD_loc"
          xlink:type="locator"/>
        <link:footnoteArc
          xlink:arcrole="http://www.xbrl.org/2003/arcrole/fact-footnote"
          xlink:from="footnoteSST-LDI-PROS000069441AAR_A_ATD_loc"
          xlink:to="footnoteSST-LDI-PROS000069441AAR_A"
          xlink:type="arc"/>
        <link:loc
          xlink:href="#footnoteSST-LDI-PROS000069441AAR_A_ATDS_loc"
          xlink:label="footnoteSST-LDI-PROS000069441AAR_A_ATDS_loc"
          xlink:type="locator"/>
        <link:footnoteArc
          xlink:arcrole="http://www.xbrl.org/2003/arcrole/fact-footnote"
          xlink:from="footnoteSST-LDI-PROS000069441AAR_A_ATDS_loc"
          xlink:to="footnoteSST-LDI-PROS000069441AAR_A"
          xlink:type="arc"/>
        <link:loc
          xlink:href="#footnoteS000075287TBF-PROAOE_AC000234189_FW"
          xlink:label="footnoteS000075287TBF-PROAOE_AC000234189_FW"
          xlink:type="locator"/>
        <link:footnote id="footnoteS000075287TBF-PROAOE_A" xlink:label="footnoteS000075287TBF-PROAOE_A" xlink:role="http://www.xbrl.org/2003/role/footnote" xlink:type="resource" xml:lang="en-US"><xhtml:div style="padding:2px"><xhtml:span> </xhtml:span><xhtml:span class="delClass" style="color:#ff0000; display:none;">
      </xhtml:span><xhtml:span
      class="redlineClass"
      style="font-family:Arial; font-size:4.5pt; vertical-align:3pt; ">A</xhtml:span><xhtml:span> </xhtml:span><xhtml:span style="font-family:Arial; font-size:8.5pt; font-style:italic">Fidelity Management &amp; Research Company LLC (FMR) has contractually agreed to reimburse the class of shares of the fund to the extent that total operating expenses (excluding interest, certain taxes, fees and expenses of the Independent Trustees, proxy and shareholder meeting expenses, extraordinary expenses, and acquired fund fees and expenses (including fees and expenses associated with a wholly owned subsidiary), if any, as well as non-operating expenses such as brokerage commissions and fees and expenses associated with the fund's securities lending program, if applicable), as a percentage of its average net assets, exceed 0.70% (the Expense Cap). If at any time during the current fiscal year expenses for the class of shares of the fund fall below the Expense Cap, FMR reserves the right to recoup through the end of the fiscal year any expenses that were reimbursed during the current fiscal year up to, but not in excess of, the Expense Cap. This arrangement will remain in effect through </xhtml:span><xhtml:span> </xhtml:span><xhtml:span style="font-family:Arial; font-size:8.5pt; font-style:italic">December 31, </xhtml:span><xhtml:span class="delClass" style="color:#ff0000; display:none;">
       </xhtml:span><xhtml:span
      class="redlineClass"
      style="font-family:Arial; font-size:8.5pt; font-style:italic; ">2026</xhtml:span><xhtml:span> </xhtml:span><xhtml:span> </xhtml:span><xhtml:span style="font-family:Arial; font-size:8.5pt; font-style:italic">. FMR may not terminate this arrangement before the expiration date without the approval of the Board of Trustees and may extend it in its discretion after that date.</xhtml:span><xhtml:span> </xhtml:span></xhtml:div></link:footnote>
        <link:footnoteArc
          xlink:arcrole="http://www.xbrl.org/2003/arcrole/fact-footnote"
          xlink:from="footnoteS000075287TBF-PROAOE_AC000234189_FW"
          xlink:to="footnoteS000075287TBF-PROAOE_A"
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        <link:loc
          xlink:href="#footnoteTBF-PROS000075287AAR_A_RBT_loc"
          xlink:label="footnoteTBF-PROS000075287AAR_A_RBT_loc"
          xlink:type="locator"/>
        <link:footnote id="footnoteTBF-PROS000075287AAR_A" xlink:label="footnoteTBF-PROS000075287AAR_A" xlink:role="http://www.xbrl.org/2003/role/footnote" xlink:type="resource" xml:lang="en-US"><xhtml:div style="padding:2px"><xhtml:span> </xhtml:span><xhtml:span style="font-family:Arial; font-size:4.67pt; vertical-align:super">A</xhtml:span><xhtml:span> </xhtml:span><xhtml:span style="font-family:Arial; font-size:8.5pt; font-style:italic">From </xhtml:span><xhtml:span> </xhtml:span><xhtml:span style="font-family:Arial; font-size:8.5pt; font-style:italic">February 10, 2022</xhtml:span><xhtml:span> </xhtml:span><xhtml:span> </xhtml:span><xhtml:span style="font-family:Arial; font-size:8.5pt; font-style:italic">.</xhtml:span><xhtml:span> </xhtml:span></xhtml:div></link:footnote>
        <link:footnoteArc
          xlink:arcrole="http://www.xbrl.org/2003/arcrole/fact-footnote"
          xlink:from="footnoteTBF-PROS000075287AAR_A_RBT_loc"
          xlink:to="footnoteTBF-PROS000075287AAR_A"
          xlink:type="arc"/>
        <link:loc
          xlink:href="#footnoteTBF-PROS000075287AAR_A_ATD_loc"
          xlink:label="footnoteTBF-PROS000075287AAR_A_ATD_loc"
          xlink:type="locator"/>
        <link:footnoteArc
          xlink:arcrole="http://www.xbrl.org/2003/arcrole/fact-footnote"
          xlink:from="footnoteTBF-PROS000075287AAR_A_ATD_loc"
          xlink:to="footnoteTBF-PROS000075287AAR_A"
          xlink:type="arc"/>
        <link:loc
          xlink:href="#footnoteTBF-PROS000075287AAR_A_ATDS_loc"
          xlink:label="footnoteTBF-PROS000075287AAR_A_ATDS_loc"
          xlink:type="locator"/>
        <link:footnoteArc
          xlink:arcrole="http://www.xbrl.org/2003/arcrole/fact-footnote"
          xlink:from="footnoteTBF-PROS000075287AAR_A_ATDS_loc"
          xlink:to="footnoteTBF-PROS000075287AAR_A"
          xlink:type="arc"/>
        <link:loc
          xlink:href="#footnoteATBF-PROS000075287SHF_AC000234191"
          xlink:label="footnoteATBF-PROS000075287SHF_AC000234191"
          xlink:type="locator"/>
        <link:footnote id="footnoteATBF-PROS000075287SHF_A" xlink:label="footnoteATBF-PROS000075287SHF_A" xlink:role="http://www.xbrl.org/2003/role/footnote" xlink:type="resource" xml:lang="en-US"><xhtml:div style="padding:2px"><xhtml:span> </xhtml:span><xhtml:span style="font-family:Arial; font-size:4.67pt; vertical-align:super">A</xhtml:span><xhtml:span> </xhtml:span><xhtml:span> </xhtml:span><xhtml:span style="font-family:Arial; font-size:8.5pt">Class A and Class M purchases of $1 million or more will not be subject to a front-end sales charge. Such Class A and Class M purchases may be subject, upon redemption, to a contingent deferred sales charge (CDSC) of 0.75% and 0.25%, respectively.</xhtml:span><xhtml:span> </xhtml:span><xhtml:span> </xhtml:span></xhtml:div></link:footnote>
        <link:footnoteArc
          xlink:arcrole="http://www.xbrl.org/2003/arcrole/fact-footnote"
          xlink:from="footnoteATBF-PROS000075287SHF_AC000234191"
          xlink:to="footnoteATBF-PROS000075287SHF_A"
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        <link:loc
          xlink:href="#footnoteATBF-PROS000075287SHF_AC000234193"
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        <link:loc
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        <link:footnote id="footnoteATBF-PROS000075287SHF_B" xlink:label="footnoteATBF-PROS000075287SHF_B" xlink:role="http://www.xbrl.org/2003/role/footnote" xlink:type="resource" xml:lang="en-US"><xhtml:div style="padding:2px"><xhtml:span> </xhtml:span><xhtml:span style="font-family:Arial; font-size:4.67pt; vertical-align:super">B</xhtml:span><xhtml:span> </xhtml:span><xhtml:span> </xhtml:span><xhtml:span style="font-family:Arial; font-size:8.5pt">On Class C shares redeemed less than one year after purchase.</xhtml:span><xhtml:span> </xhtml:span><xhtml:span> </xhtml:span></xhtml:div></link:footnote>
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        <link:loc
          xlink:href="#footnoteS000075287ATBF-PROAOE_AC000234191_FW"
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        <link:footnote id="footnoteS000075287ATBF-PROAOE_A" xlink:label="footnoteS000075287ATBF-PROAOE_A" xlink:role="http://www.xbrl.org/2003/role/footnote" xlink:type="resource" xml:lang="en-US"><xhtml:div style="padding:2px"><xhtml:span> </xhtml:span><xhtml:span class="delClass" style="color:#ff0000; display:none;">
      </xhtml:span><xhtml:span
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      style="font-family:Arial; font-size:4.5pt; vertical-align:3pt; ">A</xhtml:span><xhtml:span> </xhtml:span><xhtml:span style="font-family:Arial; font-size:8.5pt">Fidelity Management &amp; Research Company LLC (FMR) has contractually agreed to reimburse Class A, Class M, Class C, Class I, and Class Z of the fund to the extent that total operating expenses (excluding interest, certain taxes, fees and expenses of the Independent Trustees, proxy and shareholder meeting expenses, extraordinary expenses, and acquired fund fees and expenses (including fees and expenses associated with a wholly owned subsidiary), if any, as well as non-operating expenses such as brokerage commissions and fees and expenses associated with the fund's securities lending program, if applicable), as a percentage of their respective</xhtml:span><xhtml:span> </xhtml:span><xhtml:span style="font-family:Arial; font-size:8.5pt">average net assets, exceed 0.95%, 0.95%, 1.70%, 0.70%, and 0.61%</xhtml:span><xhtml:span> </xhtml:span><xhtml:span style="font-family:Arial; font-size:8.5pt">(the Expense Caps). If at any time during the current fiscal year expenses for Class A, Class M, Class C, Class I, or Class Z of the fund fall below the Expense Caps, FMR reserves the right to recoup through the end of the fiscal year any expenses that were reimbursed during the current fiscal year up to, but not in excess of, the Expense Caps. These arrangements</xhtml:span><xhtml:span> </xhtml:span><xhtml:span style="font-family:Arial; font-size:8.5pt">will remain in effect through </xhtml:span><xhtml:span> </xhtml:span><xhtml:span style="font-family:Arial; font-size:8.5pt">December 31, </xhtml:span><xhtml:span class="delClass" style="color:#ff0000; display:none;">
       </xhtml:span><xhtml:span
      class="redlineClass"
      style="font-family:Arial; font-size:8.5pt; ">2026</xhtml:span><xhtml:span> </xhtml:span><xhtml:span> </xhtml:span><xhtml:span style="font-family:Arial; font-size:8.5pt">. FMR may not terminate these arrangements</xhtml:span><xhtml:span> </xhtml:span><xhtml:span style="font-family:Arial; font-size:8.5pt">before the expiration date without the approval of the Board of Trustees and may extend them</xhtml:span><xhtml:span> </xhtml:span><xhtml:span style="font-family:Arial; font-size:8.5pt">in its discretion after that date.</xhtml:span><xhtml:span> </xhtml:span></xhtml:div></link:footnote>
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          xlink:href="#footnoteS000075287ATBF-PROAOE_AC000234190_FW"
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        <link:loc
          xlink:href="#footnoteS000075287ATBF-PROAOE_BC000234194_TW"
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        <link:footnote id="footnoteS000075287ATBF-PROAOE_B" xlink:label="footnoteS000075287ATBF-PROAOE_B" xlink:role="http://www.xbrl.org/2003/role/footnote" xlink:type="resource" xml:lang="en-US"><xhtml:div style="padding:2px"><xhtml:span> </xhtml:span><xhtml:span
      class="redlineClass"
      style="font-family:Arial; font-size:4.5pt; vertical-align:3pt; ">B</xhtml:span><xhtml:span> </xhtml:span><xhtml:span> </xhtml:span><xhtml:span
      class="redlineClass"
      style="font-family:Arial; font-size:8.5pt; ">Differs from the ratios of expenses to average net assets in the Financial Highlights section of the prospectus because of acquired fund fees and expenses. For the period, acquired fund fees and expenses are less than 0.01% and are included in other expenses. As a result, the total annual operating expenses after fee waiver and/or expense reimbursement in the fee table exceed the contractual expense limitation of the class.</xhtml:span><xhtml:span> </xhtml:span><xhtml:span> </xhtml:span></xhtml:div></link:footnote>
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        <link:loc
          xlink:href="#footnoteS000075287ATBF-PROAOE_BC000234190_TW"
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        <link:footnoteArc
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        <link:loc
          xlink:href="#footnoteATBF-PROS000075287AAR_A_RBT_loc"
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        <link:footnote id="footnoteATBF-PROS000075287AAR_A" xlink:label="footnoteATBF-PROS000075287AAR_A" xlink:role="http://www.xbrl.org/2003/role/footnote" xlink:type="resource" xml:lang="en-US"><xhtml:div style="padding:2px"><xhtml:span> </xhtml:span><xhtml:span
      class="redlineClass"
      style="font-family:Arial; font-size:4.5pt; vertical-align:3pt; ">A</xhtml:span><xhtml:span> </xhtml:span><xhtml:span
      class="redlineClass"
      style="font-family:Arial; font-size:8.5pt; font-style:italic; ">From </xhtml:span><xhtml:span> </xhtml:span><xhtml:span
      class="redlineClass"
      style="font-family:Arial; font-size:8.5pt; font-style:italic; ">February 10, 2022</xhtml:span><xhtml:span> </xhtml:span><xhtml:span> </xhtml:span><xhtml:span
      class="redlineClass"
      style="font-family:Arial; font-size:8.5pt; font-style:italic; ">.</xhtml:span><xhtml:span> </xhtml:span></xhtml:div></link:footnote>
        <link:footnoteArc
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          xlink:from="footnoteATBF-PROS000075287AAR_A_RBT_loc"
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          xlink:type="arc"/>
        <link:loc
          xlink:href="#footnoteATBF-PROS000075287AAR_A_ATD_loc"
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          xlink:type="locator"/>
        <link:footnoteArc
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          xlink:from="footnoteATBF-PROS000075287AAR_A_ATD_loc"
          xlink:to="footnoteATBF-PROS000075287AAR_A"
          xlink:type="arc"/>
        <link:loc
          xlink:href="#footnoteATBF-PROS000075287AAR_A_ATDS_loc"
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          xlink:type="locator"/>
        <link:footnoteArc
          xlink:arcrole="http://www.xbrl.org/2003/arcrole/fact-footnote"
          xlink:from="footnoteATBF-PROS000075287AAR_A_ATDS_loc"
          xlink:to="footnoteATBF-PROS000075287AAR_A"
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        <link:loc
          xlink:href="#footnoteATBF-PROS000075287AAR_B_RBT_loc"
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          xlink:type="locator"/>
        <link:footnote id="footnoteATBF-PROS000075287AAR_B" xlink:label="footnoteATBF-PROS000075287AAR_B" xlink:role="http://www.xbrl.org/2003/role/footnote" xlink:type="resource" xml:lang="en-US"><xhtml:div style="padding:2px"><xhtml:span> </xhtml:span><xhtml:span
      class="redlineClass"
      style="font-family:Arial; font-size:4.5pt; vertical-align:3pt; ">B</xhtml:span><xhtml:span> </xhtml:span><xhtml:span
      class="redlineClass"
      style="font-family:Arial; font-size:8.5pt; font-style:italic; ">From </xhtml:span><xhtml:span> </xhtml:span><xhtml:span
      class="redlineClass"
      style="font-family:Arial; font-size:8.5pt; font-style:italic; ">February 10, 2022</xhtml:span><xhtml:span> </xhtml:span><xhtml:span> </xhtml:span><xhtml:span
      class="redlineClass"
      style="font-family:Arial; font-size:8.5pt; font-style:italic; ">.</xhtml:span><xhtml:span> </xhtml:span></xhtml:div></link:footnote>
        <link:footnoteArc
          xlink:arcrole="http://www.xbrl.org/2003/arcrole/fact-footnote"
          xlink:from="footnoteATBF-PROS000075287AAR_B_RBT_loc"
          xlink:to="footnoteATBF-PROS000075287AAR_B"
          xlink:type="arc"/>
        <link:loc
          xlink:href="#footnoteATBF-PROS000075287AAR_C_RBT_loc"
          xlink:label="footnoteATBF-PROS000075287AAR_C_RBT_loc"
          xlink:type="locator"/>
        <link:footnote id="footnoteATBF-PROS000075287AAR_C" xlink:label="footnoteATBF-PROS000075287AAR_C" xlink:role="http://www.xbrl.org/2003/role/footnote" xlink:type="resource" xml:lang="en-US"><xhtml:div style="padding:2px"><xhtml:span> </xhtml:span><xhtml:span
      class="redlineClass"
      style="font-family:Arial; font-size:4.5pt; vertical-align:3pt; ">C</xhtml:span><xhtml:span> </xhtml:span><xhtml:span
      class="redlineClass"
      style="font-family:Arial; font-size:8.5pt; font-style:italic; ">From </xhtml:span><xhtml:span> </xhtml:span><xhtml:span
      class="redlineClass"
      style="font-family:Arial; font-size:8.5pt; font-style:italic; ">February 10, 2022</xhtml:span><xhtml:span> </xhtml:span><xhtml:span> </xhtml:span><xhtml:span
      class="redlineClass"
      style="font-family:Arial; font-size:8.5pt; font-style:italic; ">.</xhtml:span><xhtml:span> </xhtml:span></xhtml:div></link:footnote>
        <link:footnoteArc
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          xlink:from="footnoteATBF-PROS000075287AAR_C_RBT_loc"
          xlink:to="footnoteATBF-PROS000075287AAR_C"
          xlink:type="arc"/>
        <link:loc
          xlink:href="#footnoteATBF-PROS000075287AAR_D_RBT_loc"
          xlink:label="footnoteATBF-PROS000075287AAR_D_RBT_loc"
          xlink:type="locator"/>
        <link:footnote id="footnoteATBF-PROS000075287AAR_D" xlink:label="footnoteATBF-PROS000075287AAR_D" xlink:role="http://www.xbrl.org/2003/role/footnote" xlink:type="resource" xml:lang="en-US"><xhtml:div style="padding:2px"><xhtml:span> </xhtml:span><xhtml:span
      class="redlineClass"
      style="font-family:Arial; font-size:4.5pt; vertical-align:3pt; ">D</xhtml:span><xhtml:span> </xhtml:span><xhtml:span
      class="redlineClass"
      style="font-family:Arial; font-size:8.5pt; font-style:italic; ">From </xhtml:span><xhtml:span> </xhtml:span><xhtml:span
      class="redlineClass"
      style="font-family:Arial; font-size:8.5pt; font-style:italic; ">February 10, 2022</xhtml:span><xhtml:span> </xhtml:span><xhtml:span> </xhtml:span><xhtml:span
      class="redlineClass"
      style="font-family:Arial; font-size:8.5pt; font-style:italic; ">.</xhtml:span><xhtml:span> </xhtml:span></xhtml:div></link:footnote>
        <link:footnoteArc
          xlink:arcrole="http://www.xbrl.org/2003/arcrole/fact-footnote"
          xlink:from="footnoteATBF-PROS000075287AAR_D_RBT_loc"
          xlink:to="footnoteATBF-PROS000075287AAR_D"
          xlink:type="arc"/>
        <link:loc
          xlink:href="#footnoteATBF-PROS000075287AAR_E_RBT_loc"
          xlink:label="footnoteATBF-PROS000075287AAR_E_RBT_loc"
          xlink:type="locator"/>
        <link:footnote id="footnoteATBF-PROS000075287AAR_E" xlink:label="footnoteATBF-PROS000075287AAR_E" xlink:role="http://www.xbrl.org/2003/role/footnote" xlink:type="resource" xml:lang="en-US"><xhtml:div style="padding:2px"><xhtml:span> </xhtml:span><xhtml:span
      class="redlineClass"
      style="font-family:Arial; font-size:4.5pt; vertical-align:3pt; ">E</xhtml:span><xhtml:span> </xhtml:span><xhtml:span
      class="redlineClass"
      style="font-family:Arial; font-size:8.5pt; font-style:italic; ">From </xhtml:span><xhtml:span> </xhtml:span><xhtml:span
      class="redlineClass"
      style="font-family:Arial; font-size:8.5pt; font-style:italic; ">February 10, 2022</xhtml:span><xhtml:span> </xhtml:span><xhtml:span> </xhtml:span><xhtml:span
      class="redlineClass"
      style="font-family:Arial; font-size:8.5pt; font-style:italic; ">.</xhtml:span><xhtml:span> </xhtml:span></xhtml:div></link:footnote>
        <link:footnoteArc
          xlink:arcrole="http://www.xbrl.org/2003/arcrole/fact-footnote"
          xlink:from="footnoteATBF-PROS000075287AAR_E_RBT_loc"
          xlink:to="footnoteATBF-PROS000075287AAR_E"
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        <link:loc
          xlink:href="#footnoteS000075889SSU-PROAOE_AC000235214_FW"
          xlink:label="footnoteS000075889SSU-PROAOE_AC000235214_FW"
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        <link:footnote id="footnoteS000075889SSU-PROAOE_A" xlink:label="footnoteS000075889SSU-PROAOE_A" xlink:role="http://www.xbrl.org/2003/role/footnote" xlink:type="resource" xml:lang="en-US"><xhtml:div style="padding:2px"><xhtml:span> </xhtml:span><xhtml:span class="delClass" style="color:#ff0000; display:none;">
      </xhtml:span><xhtml:span
      class="redlineClass"
      style="font-family:Arial; font-size:4.5pt; vertical-align:3pt; ">A</xhtml:span><xhtml:span> </xhtml:span><xhtml:span style="font-family:Arial; font-size:8.5pt; font-style:italic">Fidelity Management &amp; Research Company LLC (FMR) has contractually agreed to reimburse the fund to the extent that total operating expenses (excluding interest, certain taxes, fees and expenses of the Independent Trustees, proxy and shareholder meeting expenses, extraordinary expenses, and acquired fund fees and expenses (including fees and expenses associated with a wholly owned subsidiary), if any, as well as non-operating expenses such as brokerage commissions and fees and expenses associated with the fund's securities lending program, if applicable), as a percentage of its average net assets, exceed 0.36% (the Expense Cap). If at any time during the current fiscal year expenses for the fund fall below the Expense Cap, FMR reserves the right to recoup through the end of the fiscal year any expenses that were reimbursed during the current fiscal year up to, but not in excess of, the Expense Cap. This arrangement will remain in effect through </xhtml:span><xhtml:span> </xhtml:span><xhtml:span style="font-family:Arial; font-size:8.5pt; font-style:italic">December 31, </xhtml:span><xhtml:span class="delClass" style="color:#ff0000; display:none;">
       </xhtml:span><xhtml:span
      class="redlineClass"
      style="font-family:Arial; font-size:8.5pt; font-style:italic; ">2026</xhtml:span><xhtml:span> </xhtml:span><xhtml:span> </xhtml:span><xhtml:span style="font-family:Arial; font-size:8.5pt; font-style:italic">. FMR may not terminate this arrangement before the expiration date without the approval of the Board of Trustees and may extend it in its discretion after that date.</xhtml:span><xhtml:span> </xhtml:span></xhtml:div></link:footnote>
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        <link:loc
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        <link:footnote id="footnoteSSU-PROS000075889AAR_A" xlink:label="footnoteSSU-PROS000075889AAR_A" xlink:role="http://www.xbrl.org/2003/role/footnote" xlink:type="resource" xml:lang="en-US"><xhtml:div style="padding:2px"><xhtml:span> </xhtml:span><xhtml:span style="font-family:Arial; font-size:4.67pt; vertical-align:super">A</xhtml:span><xhtml:span> </xhtml:span><xhtml:span style="font-family:Arial; font-size:8.5pt; font-style:italic">From </xhtml:span><xhtml:span> </xhtml:span><xhtml:span style="font-family:Arial; font-size:8.5pt; font-style:italic">April 13, 2022</xhtml:span><xhtml:span> </xhtml:span><xhtml:span> </xhtml:span><xhtml:span style="font-family:Arial; font-size:8.5pt; font-style:italic">.</xhtml:span><xhtml:span> </xhtml:span></xhtml:div></link:footnote>
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          xlink:to="footnoteSSU-PROS000075889AAR_A"
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        <link:loc
          xlink:href="#footnoteSSU-PROS000075889AAR_A_ATD_loc"
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        <link:footnoteArc
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          xlink:href="#footnoteSSU-PROS000075889AAR_A_ATDS_loc"
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        <link:footnoteArc
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        <link:loc
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        <link:footnote id="footnoteS000090603ECB-PROAOE_A" xlink:label="footnoteS000090603ECB-PROAOE_A" xlink:role="http://www.xbrl.org/2003/role/footnote" xlink:type="resource" xml:lang="en-US"><xhtml:div style="padding:2px"><xhtml:span> </xhtml:span><xhtml:span style="font-family:Arial; font-size:4.5pt; vertical-align:3pt">A</xhtml:span><xhtml:span> </xhtml:span><xhtml:span> </xhtml:span><xhtml:span style="font-family:Arial; font-size:8.5pt">Based on estimated amounts for the current fiscal year.</xhtml:span><xhtml:span> </xhtml:span><xhtml:span> </xhtml:span></xhtml:div></link:footnote>
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        <link:footnote id="footnoteS000090603ECB-PROAOE_B" xlink:label="footnoteS000090603ECB-PROAOE_B" xlink:role="http://www.xbrl.org/2003/role/footnote" xlink:type="resource" xml:lang="en-US"><xhtml:div style="padding:2px"><xhtml:span> </xhtml:span><xhtml:span style="font-family:Arial; font-size:4.5pt; vertical-align:3pt">B</xhtml:span><xhtml:span> </xhtml:span><xhtml:span style="font-family:Arial; font-size:8.5pt; font-style:italic">Fidelity Management &amp; Research Company LLC (FMR) has contractually agreed to reimburse the fund to the extent that total operating expenses (excluding interest, certain taxes, fees and expenses of the Independent Trustees, proxy and shareholder meeting expenses, extraordinary expenses, and acquired fund fees and expenses (including fees and expenses associated with a wholly owned subsidiary), if any, as well as non-operating expenses such as brokerage commissions and fees and expenses associated with the fund's securities lending program, if applicable), as a percentage of its average net assets, exceed 0.15% (the Expense Cap). If at any time during the current fiscal year expenses for the fund fall below the Expense Cap, FMR reserves the right to recoup through the end of the fiscal year any expenses that were reimbursed during the current fiscal year up to, but not in excess of, the Expense Cap. This arrangement will remain in effect through </xhtml:span><xhtml:span> </xhtml:span><xhtml:span style="font-family:Arial; font-size:8.5pt; font-style:italic">December 31, 2026</xhtml:span><xhtml:span> </xhtml:span><xhtml:span> </xhtml:span><xhtml:span style="font-family:Arial; font-size:8.5pt; font-style:italic">. FMR may not terminate this arrangement before the expiration date without the approval of the Board of Trustees and may extend it in its discretion after that date.</xhtml:span><xhtml:span> </xhtml:span></xhtml:div></link:footnote>
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