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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>
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    <dei:AmendmentFlag contextRef="Trust" id="ixv-86085">false</dei:AmendmentFlag>
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    <dei:EntityInvCompanyType contextRef="Trust" id="ixv-86087">N-1A</dei:EntityInvCompanyType>
    <dei:EntityRegistrantName contextRef="Trust" id="ixv-86088">Fidelity Income Fund</dei:EntityRegistrantName>
    <oef:RiskReturnHeading
      contextRef="Pid_S000057288_contentCd_TBDK6-PRO"
      id="ixv-211">


     Fund Summary

     Fund:
     Fidelity&#xae; Total Bond K6 Fund

   </oef:RiskReturnHeading>
    <oef:ObjectiveHeading
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     Investment Objective


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     Fidelity&#xae; Total Bond K6 Fund seeks a high level of current income.


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      contextRef="Pid_S000057288_contentCd_TBDK6-PRO"
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     Fee Table


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      id="ixv-236">


     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.

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      id="ixv-247">


     Shareholder fees


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    <oef:ShareholderFeeOther
      contextRef="Pid_S000057288_contentCd_TBDK6-PRO"
      decimals="0"
      id="ixv-89397"
      unitRef="usd">0</oef:ShareholderFeeOther>
    <oef:OperatingExpensesCaption
      contextRef="Pid_S000057288_contentCd_TBDK6-PRO"
      id="ixv-262">


     Annual Operating Expenses


   </oef:OperatingExpensesCaption>
    <oef:ManagementFeesOverAssets
      contextRef="Pid_S000057288_Cid_C000182864"
      decimals="6"
      id="ixv-89398"
      unitRef="pure">0.0030</oef:ManagementFeesOverAssets>
    <oef:DistributionAndService12b1FeesOverAssets
      contextRef="Pid_S000057288_Cid_C000182864"
      decimals="6"
      id="ixv-89399"
      unitRef="pure">0</oef:DistributionAndService12b1FeesOverAssets>
    <oef:OtherExpensesOverAssets
      contextRef="Pid_S000057288_Cid_C000182864"
      decimals="6"
      id="ixv-89400"
      unitRef="pure">0.0000</oef:OtherExpensesOverAssets>
    <oef:ExpensesOverAssets
      contextRef="Pid_S000057288_Cid_C000182864"
      decimals="6"
      id="ixv-89401"
      unitRef="pure">0.0030</oef:ExpensesOverAssets>
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      contextRef="Pid_S000057288_contentCd_TBDK6-PRO"
      id="ixv-309">


     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_S000057288_Cid_C000182864"
      decimals="0"
      id="ixv-89402"
      unitRef="usd">31</oef:ExpenseExampleYear01>
    <oef:ExpenseExampleYear03
      contextRef="Pid_S000057288_Cid_C000182864"
      decimals="0"
      id="ixv-89403"
      unitRef="usd">97</oef:ExpenseExampleYear03>
    <oef:ExpenseExampleYear05
      contextRef="Pid_S000057288_Cid_C000182864"
      decimals="0"
      id="ixv-89404"
      unitRef="usd">169</oef:ExpenseExampleYear05>
    <oef:ExpenseExampleYear10
      contextRef="Pid_S000057288_Cid_C000182864"
      decimals="0"
      id="ixv-89405"
      unitRef="usd">381</oef:ExpenseExampleYear10>
    <oef:PortfolioTurnoverHeading
      contextRef="Pid_S000057288_contentCd_TBDK6-PRO"
      id="ixv-366">


     Portfolio Turnover


   </oef:PortfolioTurnoverHeading>
    <oef:PortfolioTurnoverTextBlock
      contextRef="Pid_S000057288_contentCd_TBDK6-PRO"
      id="ixv-371">


     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



       228


     % of the average value of its portfolio.


   </oef:PortfolioTurnoverTextBlock>
    <oef:PortfolioTurnoverRate
      contextRef="Pid_S000057288_contentCd_TBDK6-PRO"
      decimals="4"
      id="ixv-89406"
      unitRef="pure">2.28</oef:PortfolioTurnoverRate>
    <oef:StrategyHeading
      contextRef="Pid_S000057288_contentCd_TBDK6-PRO"
      id="ixv-380">


     Principal Investment Strategies


   </oef:StrategyHeading>
    <oef:StrategyNarrativeTextBlock
      contextRef="Pid_S000057288_contentCd_TBDK6-PRO"
      id="ixv-385">




        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.
      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_S000057288_contentCd_TBDK6-PRO_RiskMember_InterestRateChangesMember"
      id="ixv-424">



      Interest Rate Changes.

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

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000057288_contentCd_TBDK6-PRO_RiskMember_ForeignExposureMember"
      id="ixv-433">



      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_S000057288_contentCd_TBDK6-PRO_RiskMember_PrepaymentMember"
      id="ixv-444">



      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_S000057288_contentCd_TBDK6-PRO_RiskMember_IssuerSpecificChangesMember"
      id="ixv-453">



      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_S000057288_contentCd_TBDK6-PRO_RiskMember_LeverageRiskMember"
      id="ixv-472">



      Leverage Risk.

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

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000057288_contentCd_TBDK6-PRO_RiskMember_HighPortfolioTurnoverMember"
      id="ixv-481">



      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_S000057288_contentCd_TBDK6-PRO_RiskMember_RiskNotInsuredDepositoryInstitutionMember"
      id="ixv-491">


     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_S000057288_contentCd_TBDK6-PRO_RiskMember_RiskLoseMoneyMember"
      id="ixv-499">


     &#160;

     You could lose money by investing in the fund.


   </oef:RiskTextBlock>
    <oef:BarChartAndPerformanceTableHeading
      contextRef="Pid_S000057288_contentCd_TBDK6-PRO"
      id="ixv-508">


     Performance


   </oef:BarChartAndPerformanceTableHeading>
    <oef:PerformanceNarrativeTextBlock
      contextRef="Pid_S000057288_contentCd_TBDK6-PRO"
      id="ixv-513">



       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 is not an indication of future performance.


     Visit



      www.401k.com


     and log in for more recent performance information.

   </oef:PerformanceNarrativeTextBlock>
    <oef:PerformanceInformationIllustratesVariabilityOfReturns
      contextRef="Pid_S000057288_contentCd_TBDK6-PRO"
      id="ixv-519">

      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_S000057288_contentCd_TBDK6-PRO"
      id="ixv-533">

      Past performance is not an indication of future performance.

     </oef:PerformancePastDoesNotIndicateFuture>
    <oef:PerformanceAvailabilityWebSiteAddress
      contextRef="Pid_S000057288_contentCd_TBDK6-PRO"
      id="ixv-539">

      www.401k.com
     </oef:PerformanceAvailabilityWebSiteAddress>
    <oef:BarChartHeading
      contextRef="Pid_S000057288_contentCd_TBDK6-PRO"
      id="ixv-544">


     Year-by-Year Returns

   </oef:BarChartHeading>
    <oef:AnnlRtrPct
      contextRef="Pid_S000057288_Cid_C000182864_2018"
      decimals="INF"
      id="ixv-89407"
      unitRef="pure">-0.0077</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000057288_Cid_C000182864_2019"
      decimals="INF"
      id="ixv-89408"
      unitRef="pure">0.1002</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000057288_Cid_C000182864_2020"
      decimals="INF"
      id="ixv-89409"
      unitRef="pure">0.0953</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000057288_Cid_C000182864_2021"
      decimals="INF"
      id="ixv-89410"
      unitRef="pure">-0.0010</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000057288_Cid_C000182864_2022"
      decimals="INF"
      id="ixv-89411"
      unitRef="pure">-0.1256</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000057288_Cid_C000182864_2023"
      decimals="INF"
      id="ixv-89412"
      unitRef="pure">0.0707</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000057288_Cid_C000182864_2024"
      decimals="INF"
      id="ixv-89413"
      unitRef="pure">0.0233</oef:AnnlRtrPct>
    <oef:HighestQuarterlyReturnLabel
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      id="ixv-647">
          &#160;&#160;&#160;Highest Quarter Return
        </oef:HighestQuarterlyReturnLabel>
    <oef:BarChartHighestQuarterlyReturn
      contextRef="Pid_S000057288_contentCd_TBDK6-PRO"
      decimals="4"
      id="ixv-89414"
      unitRef="pure">0.0686</oef:BarChartHighestQuarterlyReturn>
    <oef:BarChartHighestQuarterlyReturnDate
      contextRef="Pid_S000057288_contentCd_TBDK6-PRO"
      id="ixv-657">2023-12-31</oef:BarChartHighestQuarterlyReturnDate>
    <oef:LowestQuarterlyReturnLabel
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      id="ixv-662">
          &#160;&#160;&#160;Lowest Quarter Return
        </oef:LowestQuarterlyReturnLabel>
    <oef:BarChartLowestQuarterlyReturn
      contextRef="Pid_S000057288_contentCd_TBDK6-PRO"
      decimals="4"
      id="ixv-89415"
      unitRef="pure">-0.0571</oef:BarChartLowestQuarterlyReturn>
    <oef:BarChartLowestQuarterlyReturnDate
      contextRef="Pid_S000057288_contentCd_TBDK6-PRO"
      id="ixv-673">2022-06-30</oef:BarChartLowestQuarterlyReturnDate>
    <oef:YearToDateReturnLabel
      contextRef="Pid_S000057288_contentCd_TBDK6-PRO"
      id="ixv-678">
          &#160;&#160;&#160;Year-to-Date Return
        </oef:YearToDateReturnLabel>
    <oef:BarChartYearToDateReturn
      contextRef="Pid_S000057288_contentCd_TBDK6-PRO"
      decimals="4"
      id="ixv-89416"
      unitRef="pure">0.0646</oef:BarChartYearToDateReturn>
    <oef:BarChartYearToDateReturnDate
      contextRef="Pid_S000057288_contentCd_TBDK6-PRO"
      id="ixv-688">2025-09-30</oef:BarChartYearToDateReturnDate>
    <oef:PerformanceTableHeading
      contextRef="Pid_S000057288_contentCd_TBDK6-PRO"
      id="ixv-693">


     Average Annual Returns


   </oef:PerformanceTableHeading>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000057288_Cid_C000182864_ReturnBeforeTaxes_01"
      id="ixv-727">
         Fidelity&#xae; Total Bond K6 Fund
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000057288_Cid_C000182864_ReturnBeforeTaxes_01"
      decimals="4"
      id="ixv-89417"
      unitRef="pure">0.0233</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000057288_Cid_C000182864_ReturnBeforeTaxes_05"
      decimals="4"
      id="ixv-89418"
      unitRef="pure">0.0095</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000057288_Cid_C000182864_ReturnBeforeTaxes_AverageAnnualReturnSinceInception"
      decimals="4"
      id="footnoteTBDK6-PROS000057288AAR_A_RBT_loc"
      unitRef="pure">0.0199</oef:AvgAnnlRtrPct>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000057288_Indexid_LB001_contentCd_TBDK6-PRO_01"
      id="ixv-742">
         Bloomberg U.S. Aggregate Bond Index
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000057288_Indexid_LB001_contentCd_TBDK6-PRO_01"
      decimals="4"
      id="ixv-89420"
      unitRef="pure">0.0125</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000057288_Indexid_LB001_contentCd_TBDK6-PRO_05"
      decimals="4"
      id="ixv-89421"
      unitRef="pure">-0.0033</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000057288_Indexid_LB001_contentCd_TBDK6-PRO_AverageAnnualReturnSinceInception"
      decimals="4"
      id="ixv-89422"
      unitRef="pure">0.0108</oef:AvgAnnlRtrPct>
    <oef:AnnualReturnInceptionDate contextRef="Pid_S000057288_Cid_C000182864" id="ixv-784">2017-05-25</oef:AnnualReturnInceptionDate>
    <oef:RiskReturnHeading contextRef="Pid_S000007066_contentCd_TBD-PRO" id="ixv-2593">


     Fund Summary

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

   </oef:RiskReturnHeading>
    <oef:ObjectiveHeading contextRef="Pid_S000007066_contentCd_TBD-PRO" id="ixv-2606">


     Investment Objective


   </oef:ObjectiveHeading>
    <oef:ObjectivePrimaryTextBlock contextRef="Pid_S000007066_contentCd_TBD-PRO" id="ixv-2611">


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


   </oef:ObjectivePrimaryTextBlock>
    <oef:ExpenseHeading contextRef="Pid_S000007066_contentCd_TBD-PRO" id="ixv-2616">


     Fee Table


   </oef:ExpenseHeading>
    <oef:ExpenseNarrativeTextBlock contextRef="Pid_S000007066_contentCd_TBD-PRO" id="ixv-2622">


     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_S000007066_contentCd_TBD-PRO" id="ixv-2633">


     Shareholder fees


   </oef:ShareholderFeesCaption>
    <oef:ShareholderFeeOther
      contextRef="Pid_S000007066_contentCd_TBD-PRO"
      decimals="0"
      id="ixv-89423"
      unitRef="usd">0</oef:ShareholderFeeOther>
    <oef:OperatingExpensesCaption contextRef="Pid_S000007066_contentCd_TBD-PRO" id="ixv-2648">


     Annual Operating Expenses


   </oef:OperatingExpensesCaption>
    <oef:ManagementFeesOverAssets
      contextRef="Pid_S000007066_Cid_C000019272"
      decimals="6"
      id="ixv-89424"
      unitRef="pure">0.0028</oef:ManagementFeesOverAssets>
    <oef:DistributionAndService12b1FeesOverAssets
      contextRef="Pid_S000007066_Cid_C000019272"
      decimals="6"
      id="ixv-89425"
      unitRef="pure">0</oef:DistributionAndService12b1FeesOverAssets>
    <oef:OtherExpensesOverAssets
      contextRef="Pid_S000007066_Cid_C000019272"
      decimals="6"
      id="ixv-89426"
      unitRef="pure">0.0017</oef:OtherExpensesOverAssets>
    <oef:ExpensesOverAssets
      contextRef="Pid_S000007066_Cid_C000019272"
      decimals="6"
      id="ixv-89427"
      unitRef="pure">0.0045</oef:ExpensesOverAssets>
    <oef:ExpenseExampleNarrativeTextBlock contextRef="Pid_S000007066_contentCd_TBD-PRO" id="ixv-2695">




     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_S000007066_Cid_C000019272"
      decimals="0"
      id="ixv-89428"
      unitRef="usd">46</oef:ExpenseExampleYear01>
    <oef:ExpenseExampleYear03
      contextRef="Pid_S000007066_Cid_C000019272"
      decimals="0"
      id="ixv-89429"
      unitRef="usd">144</oef:ExpenseExampleYear03>
    <oef:ExpenseExampleYear05
      contextRef="Pid_S000007066_Cid_C000019272"
      decimals="0"
      id="ixv-89430"
      unitRef="usd">252</oef:ExpenseExampleYear05>
    <oef:ExpenseExampleYear10
      contextRef="Pid_S000007066_Cid_C000019272"
      decimals="0"
      id="ixv-89431"
      unitRef="usd">567</oef:ExpenseExampleYear10>
    <oef:PortfolioTurnoverHeading contextRef="Pid_S000007066_contentCd_TBD-PRO" id="ixv-2753">


     Portfolio Turnover


   </oef:PortfolioTurnoverHeading>
    <oef:PortfolioTurnoverTextBlock contextRef="Pid_S000007066_contentCd_TBD-PRO" id="ixv-2758">


     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



       211


     % of the average value of its portfolio.


   </oef:PortfolioTurnoverTextBlock>
    <oef:PortfolioTurnoverRate
      contextRef="Pid_S000007066_contentCd_TBD-PRO"
      decimals="4"
      id="ixv-89432"
      unitRef="pure">2.11</oef:PortfolioTurnoverRate>
    <oef:StrategyHeading contextRef="Pid_S000007066_contentCd_TBD-PRO" id="ixv-2767">


     Principal Investment Strategies


   </oef:StrategyHeading>
    <oef:StrategyNarrativeTextBlock contextRef="Pid_S000007066_contentCd_TBD-PRO" id="ixv-2772">




        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.
      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_S000007066_contentCd_TBD-PRO_RiskMember_InterestRateChangesMember"
      id="ixv-2814">



      Interest Rate Changes.

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

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000007066_contentCd_TBD-PRO_RiskMember_ForeignExposureMember"
      id="ixv-2823">



      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_S000007066_contentCd_TBD-PRO_RiskMember_PrepaymentMember"
      id="ixv-2834">



      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_S000007066_contentCd_TBD-PRO_RiskMember_IssuerSpecificChangesMember"
      id="ixv-2843">



      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_S000007066_contentCd_TBD-PRO_RiskMember_LeverageRiskMember"
      id="ixv-2862">



      Leverage Risk.

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

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000007066_contentCd_TBD-PRO_RiskMember_HighPortfolioTurnoverMember"
      id="ixv-2871">



      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_S000007066_contentCd_TBD-PRO_RiskMember_RiskNotInsuredDepositoryInstitutionMember"
      id="ixv-2881">


     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_S000007066_contentCd_TBD-PRO_RiskMember_RiskLoseMoneyMember"
      id="ixv-2889">


     &#160;

     You could lose money by investing in the fund.


   </oef:RiskTextBlock>
    <oef:BarChartAndPerformanceTableHeading contextRef="Pid_S000007066_contentCd_TBD-PRO" id="ixv-2898">


     Performance


   </oef:BarChartAndPerformanceTableHeading>
    <oef:PerformanceNarrativeTextBlock contextRef="Pid_S000007066_contentCd_TBD-PRO" id="ixv-2903">



       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_S000007066_contentCd_TBD-PRO" id="ixv-2909">

      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_S000007066_contentCd_TBD-PRO" id="ixv-2923">

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

     </oef:PerformancePastDoesNotIndicateFuture>
    <oef:PerformanceAvailabilityWebSiteAddress contextRef="Pid_S000007066_contentCd_TBD-PRO" id="ixv-2929">

      www.fidelity.com
     </oef:PerformanceAvailabilityWebSiteAddress>
    <oef:BarChartHeading contextRef="Pid_S000007066_contentCd_TBD-PRO" id="ixv-2934">


     Year-by-Year Returns

   </oef:BarChartHeading>
    <oef:AnnlRtrPct
      contextRef="Pid_S000007066_Cid_C000019272_2015"
      decimals="INF"
      id="ixv-89433"
      unitRef="pure">-0.0042</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000007066_Cid_C000019272_2016"
      decimals="INF"
      id="ixv-89434"
      unitRef="pure">0.0585</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000007066_Cid_C000019272_2017"
      decimals="INF"
      id="ixv-89435"
      unitRef="pure">0.0418</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000007066_Cid_C000019272_2018"
      decimals="INF"
      id="ixv-89436"
      unitRef="pure">-0.0067</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000007066_Cid_C000019272_2019"
      decimals="INF"
      id="ixv-89437"
      unitRef="pure">0.0987</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000007066_Cid_C000019272_2020"
      decimals="INF"
      id="ixv-89438"
      unitRef="pure">0.0934</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000007066_Cid_C000019272_2021"
      decimals="INF"
      id="ixv-89439"
      unitRef="pure">-0.0009</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000007066_Cid_C000019272_2022"
      decimals="INF"
      id="ixv-89440"
      unitRef="pure">-0.1291</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000007066_Cid_C000019272_2023"
      decimals="INF"
      id="ixv-89441"
      unitRef="pure">0.0723</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000007066_Cid_C000019272_2024"
      decimals="INF"
      id="ixv-89442"
      unitRef="pure">0.0249</oef:AnnlRtrPct>
    <oef:HighestQuarterlyReturnLabel contextRef="Pid_S000007066_contentCd_TBD-PRO" id="ixv-3047">
          &#160;&#160;&#160;Highest Quarter Return
        </oef:HighestQuarterlyReturnLabel>
    <oef:BarChartHighestQuarterlyReturn
      contextRef="Pid_S000007066_contentCd_TBD-PRO"
      decimals="4"
      id="ixv-89443"
      unitRef="pure">0.0682</oef:BarChartHighestQuarterlyReturn>
    <oef:BarChartHighestQuarterlyReturnDate contextRef="Pid_S000007066_contentCd_TBD-PRO" id="ixv-3057">2023-12-31</oef:BarChartHighestQuarterlyReturnDate>
    <oef:LowestQuarterlyReturnLabel contextRef="Pid_S000007066_contentCd_TBD-PRO" id="ixv-3062">
          &#160;&#160;&#160;Lowest Quarter Return
        </oef:LowestQuarterlyReturnLabel>
    <oef:BarChartLowestQuarterlyReturn
      contextRef="Pid_S000007066_contentCd_TBD-PRO"
      decimals="4"
      id="ixv-89444"
      unitRef="pure">-0.0619</oef:BarChartLowestQuarterlyReturn>
    <oef:BarChartLowestQuarterlyReturnDate contextRef="Pid_S000007066_contentCd_TBD-PRO" id="ixv-3073">2022-06-30</oef:BarChartLowestQuarterlyReturnDate>
    <oef:YearToDateReturnLabel contextRef="Pid_S000007066_contentCd_TBD-PRO" id="ixv-3078">
          &#160;&#160;&#160;Year-to-Date Return
        </oef:YearToDateReturnLabel>
    <oef:BarChartYearToDateReturn
      contextRef="Pid_S000007066_contentCd_TBD-PRO"
      decimals="4"
      id="ixv-89445"
      unitRef="pure">0.0647</oef:BarChartYearToDateReturn>
    <oef:BarChartYearToDateReturnDate contextRef="Pid_S000007066_contentCd_TBD-PRO" id="ixv-3088">2025-09-30</oef:BarChartYearToDateReturnDate>
    <oef:PerformanceTableHeading contextRef="Pid_S000007066_contentCd_TBD-PRO" id="ixv-3093">


     Average Annual Returns


   </oef:PerformanceTableHeading>
    <oef:PerformanceTableNarrativeTextBlock contextRef="Pid_S000007066_contentCd_TBD-PRO" id="ixv-3098">




      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_S000007066_contentCd_TBD-PRO" id="ixv-3101">

      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_S000007066_contentCd_TBD-PRO" id="ixv-3108">

      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_S000007066_contentCd_TBD-PRO" id="ixv-3113">

      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_S000007066_Cid_C000019272_ReturnBeforeTaxes_01"
      id="ixv-3158">
         Return Before Taxes
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007066_Cid_C000019272_ReturnBeforeTaxes_01"
      decimals="4"
      id="ixv-89446"
      unitRef="pure">0.0249</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007066_Cid_C000019272_ReturnBeforeTaxes_05"
      decimals="4"
      id="ixv-89447"
      unitRef="pure">0.0089</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007066_Cid_C000019272_ReturnBeforeTaxes_10"
      decimals="4"
      id="ixv-89448"
      unitRef="pure">0.0228</oef:AvgAnnlRtrPct>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000007066_Cid_C000019272_AfterTaxesOnDistributions_01"
      id="ixv-3173">
         Return After Taxes on Distributions
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007066_Cid_C000019272_AfterTaxesOnDistributions_01"
      decimals="4"
      id="ixv-89449"
      unitRef="pure">0.0083</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007066_Cid_C000019272_AfterTaxesOnDistributions_05"
      decimals="4"
      id="ixv-89450"
      unitRef="pure">-0.0060</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007066_Cid_C000019272_AfterTaxesOnDistributions_10"
      decimals="4"
      id="ixv-89451"
      unitRef="pure">0.0085</oef:AvgAnnlRtrPct>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000007066_Cid_C000019272_AfterTaxesOnDistributionsAndSales_01"
      id="ixv-3189">
         Return After Taxes on Distributions and Sale of Fund Shares
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007066_Cid_C000019272_AfterTaxesOnDistributionsAndSales_01"
      decimals="4"
      id="ixv-89452"
      unitRef="pure">0.0165</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007066_Cid_C000019272_AfterTaxesOnDistributionsAndSales_05"
      decimals="4"
      id="ixv-89453"
      unitRef="pure">0.0010</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007066_Cid_C000019272_AfterTaxesOnDistributionsAndSales_10"
      decimals="4"
      id="ixv-89454"
      unitRef="pure">0.0115</oef:AvgAnnlRtrPct>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000007066_Indexid_LB001_contentCd_TBD-PRO_01"
      id="ixv-3205">
         Bloomberg U.S. Aggregate Bond Index
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007066_Indexid_LB001_contentCd_TBD-PRO_01"
      decimals="4"
      id="ixv-89455"
      unitRef="pure">0.0125</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007066_Indexid_LB001_contentCd_TBD-PRO_05"
      decimals="4"
      id="ixv-89456"
      unitRef="pure">-0.0033</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007066_Indexid_LB001_contentCd_TBD-PRO_10"
      decimals="4"
      id="ixv-89457"
      unitRef="pure">0.0135</oef:AvgAnnlRtrPct>
    <oef:RiskReturnHeading contextRef="Pid_S000007066_contentCd_ATB-PRO" id="ixv-5358">


     Fund Summary

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

   </oef:RiskReturnHeading>
    <oef:ObjectiveHeading contextRef="Pid_S000007066_contentCd_ATB-PRO" id="ixv-5373">


     Investment Objective


   </oef:ObjectiveHeading>
    <oef:ObjectivePrimaryTextBlock contextRef="Pid_S000007066_contentCd_ATB-PRO" id="ixv-5378">


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


   </oef:ObjectivePrimaryTextBlock>
    <oef:ExpenseHeading contextRef="Pid_S000007066_contentCd_ATB-PRO" id="ixv-5383">


     Fee Table


   </oef:ExpenseHeading>
    <oef:ExpenseNarrativeTextBlock contextRef="Pid_S000007066_contentCd_ATB-PRO" id="ixv-5389">


     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


      36

      of the prospectus



     and in

     the sales charge

     waiver appendix to

     the prospectus.

   </oef:ExpenseNarrativeTextBlock>
    <oef:ExpenseBreakpointDiscounts contextRef="Pid_S000007066_contentCd_ATB-PRO" id="ixv-5395">

      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


      36

      of the prospectus

     </oef:ExpenseBreakpointDiscounts>
    <oef:ExpenseBreakpointMinimumInvestmentRequiredAmount
      contextRef="Pid_S000007066_contentCd_ATB-PRO"
      decimals="0"
      id="ixv-89458"
      unitRef="usd">50000</oef:ExpenseBreakpointMinimumInvestmentRequiredAmount>
    <oef:ShareholderFeesCaption contextRef="Pid_S000007066_contentCd_ATB-PRO" id="ixv-5420">


     Shareholder fees


   </oef:ShareholderFeesCaption>
    <oef:MaximumCumulativeSalesChargeOverOfferingPrice
      contextRef="Pid_S000007066_Cid_C000019273"
      decimals="4"
      id="ixv-89459"
      unitRef="pure">0.0400</oef:MaximumCumulativeSalesChargeOverOfferingPrice>
    <oef:MaximumCumulativeSalesChargeOverOfferingPrice
      contextRef="Pid_S000007066_Cid_C000019276"
      decimals="4"
      id="ixv-89460"
      unitRef="pure">0.0400</oef:MaximumCumulativeSalesChargeOverOfferingPrice>
    <oef:MaximumCumulativeSalesChargeOverOfferingPrice
      contextRef="Pid_S000007066_Cid_C000019275"
      decimals="4"
      id="ixv-89461"
      unitRef="pure">0</oef:MaximumCumulativeSalesChargeOverOfferingPrice>
    <oef:MaximumCumulativeSalesChargeOverOfferingPrice
      contextRef="Pid_S000007066_Cid_C000019277"
      decimals="4"
      id="ixv-89462"
      unitRef="pure">0</oef:MaximumCumulativeSalesChargeOverOfferingPrice>
    <oef:MaximumCumulativeSalesChargeOverOfferingPrice
      contextRef="Pid_S000007066_Cid_C000150510"
      decimals="4"
      id="ixv-89463"
      unitRef="pure">0</oef:MaximumCumulativeSalesChargeOverOfferingPrice>
    <oef:MaximumDeferredSalesChargeOverOther
      contextRef="Pid_S000007066_Cid_C000019273"
      decimals="4"
      id="footnoteATB-PROS000007066SHF_AC000019273"
      unitRef="pure">0</oef:MaximumDeferredSalesChargeOverOther>
    <oef:MaximumDeferredSalesChargeOverOther
      contextRef="Pid_S000007066_Cid_C000019276"
      decimals="4"
      id="footnoteATB-PROS000007066SHF_AC000019276"
      unitRef="pure">0</oef:MaximumDeferredSalesChargeOverOther>
    <oef:MaximumDeferredSalesChargeOverOther
      contextRef="Pid_S000007066_Cid_C000019275"
      decimals="4"
      id="footnoteATB-PROS000007066SHF_BC000019275"
      unitRef="pure">0.0100</oef:MaximumDeferredSalesChargeOverOther>
    <oef:MaximumDeferredSalesChargeOverOther
      contextRef="Pid_S000007066_Cid_C000019277"
      decimals="4"
      id="ixv-89467"
      unitRef="pure">0</oef:MaximumDeferredSalesChargeOverOther>
    <oef:MaximumDeferredSalesChargeOverOther
      contextRef="Pid_S000007066_Cid_C000150510"
      decimals="4"
      id="ixv-89468"
      unitRef="pure">0</oef:MaximumDeferredSalesChargeOverOther>
    <oef:ExpensesDeferredChargesTextBlock contextRef="Pid_S000007066_contentCd_ATB-PRO" id="ixv-5526">

      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_S000007066_Cid_C000019275" id="ixv-5536">

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

     </oef:ExpensesDeferredChargesTextBlock>
    <oef:OperatingExpensesCaption contextRef="Pid_S000007066_contentCd_ATB-PRO" id="ixv-5541">


     Annual Operating Expenses


   </oef:OperatingExpensesCaption>
    <oef:ManagementFeesOverAssets
      contextRef="Pid_S000007066_Cid_C000019273"
      decimals="6"
      id="ixv-89469"
      unitRef="pure">0.0028</oef:ManagementFeesOverAssets>
    <oef:ManagementFeesOverAssets
      contextRef="Pid_S000007066_Cid_C000019276"
      decimals="6"
      id="ixv-89470"
      unitRef="pure">0.0028</oef:ManagementFeesOverAssets>
    <oef:ManagementFeesOverAssets
      contextRef="Pid_S000007066_Cid_C000019275"
      decimals="6"
      id="ixv-89471"
      unitRef="pure">0.0028</oef:ManagementFeesOverAssets>
    <oef:ManagementFeesOverAssets
      contextRef="Pid_S000007066_Cid_C000019277"
      decimals="6"
      id="ixv-89472"
      unitRef="pure">0.0028</oef:ManagementFeesOverAssets>
    <oef:ManagementFeesOverAssets
      contextRef="Pid_S000007066_Cid_C000150510"
      decimals="6"
      id="ixv-89473"
      unitRef="pure">0.0028</oef:ManagementFeesOverAssets>
    <oef:DistributionAndService12b1FeesOverAssets
      contextRef="Pid_S000007066_Cid_C000019273"
      decimals="6"
      id="ixv-89474"
      unitRef="pure">0.0025</oef:DistributionAndService12b1FeesOverAssets>
    <oef:DistributionAndService12b1FeesOverAssets
      contextRef="Pid_S000007066_Cid_C000019276"
      decimals="6"
      id="ixv-89475"
      unitRef="pure">0.0025</oef:DistributionAndService12b1FeesOverAssets>
    <oef:DistributionAndService12b1FeesOverAssets
      contextRef="Pid_S000007066_Cid_C000019275"
      decimals="6"
      id="ixv-89476"
      unitRef="pure">0.0100</oef:DistributionAndService12b1FeesOverAssets>
    <oef:DistributionAndService12b1FeesOverAssets
      contextRef="Pid_S000007066_Cid_C000019277"
      decimals="6"
      id="ixv-89477"
      unitRef="pure">0</oef:DistributionAndService12b1FeesOverAssets>
    <oef:DistributionAndService12b1FeesOverAssets
      contextRef="Pid_S000007066_Cid_C000150510"
      decimals="6"
      id="ixv-89478"
      unitRef="pure">0</oef:DistributionAndService12b1FeesOverAssets>
    <oef:OtherExpensesOverAssets
      contextRef="Pid_S000007066_Cid_C000019273"
      decimals="6"
      id="ixv-89479"
      unitRef="pure">0.0022</oef:OtherExpensesOverAssets>
    <oef:OtherExpensesOverAssets
      contextRef="Pid_S000007066_Cid_C000019276"
      decimals="6"
      id="ixv-89480"
      unitRef="pure">0.0022</oef:OtherExpensesOverAssets>
    <oef:OtherExpensesOverAssets
      contextRef="Pid_S000007066_Cid_C000019275"
      decimals="6"
      id="ixv-89481"
      unitRef="pure">0.0023</oef:OtherExpensesOverAssets>
    <oef:OtherExpensesOverAssets
      contextRef="Pid_S000007066_Cid_C000019277"
      decimals="6"
      id="ixv-89482"
      unitRef="pure">0.0022</oef:OtherExpensesOverAssets>
    <oef:OtherExpensesOverAssets
      contextRef="Pid_S000007066_Cid_C000150510"
      decimals="6"
      id="ixv-89483"
      unitRef="pure">0.0012</oef:OtherExpensesOverAssets>
    <oef:ExpensesOverAssets
      contextRef="Pid_S000007066_Cid_C000019273"
      decimals="6"
      id="ixv-89484"
      unitRef="pure">0.0075</oef:ExpensesOverAssets>
    <oef:ExpensesOverAssets
      contextRef="Pid_S000007066_Cid_C000019276"
      decimals="6"
      id="ixv-89485"
      unitRef="pure">0.0075</oef:ExpensesOverAssets>
    <oef:ExpensesOverAssets
      contextRef="Pid_S000007066_Cid_C000019275"
      decimals="6"
      id="ixv-89486"
      unitRef="pure">0.0151</oef:ExpensesOverAssets>
    <oef:ExpensesOverAssets
      contextRef="Pid_S000007066_Cid_C000019277"
      decimals="6"
      id="ixv-89487"
      unitRef="pure">0.0050</oef:ExpensesOverAssets>
    <oef:ExpensesOverAssets
      contextRef="Pid_S000007066_Cid_C000150510"
      decimals="6"
      id="ixv-89488"
      unitRef="pure">0.0040</oef:ExpensesOverAssets>
    <oef:FeeWaiverOrReimbursementOverAssets
      contextRef="Pid_S000007066_Cid_C000019273"
      decimals="6"
      id="ixv-89489"
      unitRef="pure">-0.0000</oef:FeeWaiverOrReimbursementOverAssets>
    <oef:FeeWaiverOrReimbursementOverAssets
      contextRef="Pid_S000007066_Cid_C000019276"
      decimals="6"
      id="ixv-89490"
      unitRef="pure">-0.0000</oef:FeeWaiverOrReimbursementOverAssets>
    <oef:FeeWaiverOrReimbursementOverAssets
      contextRef="Pid_S000007066_Cid_C000019275"
      decimals="6"
      id="ixv-89491"
      unitRef="pure">-0.0000</oef:FeeWaiverOrReimbursementOverAssets>
    <oef:FeeWaiverOrReimbursementOverAssets
      contextRef="Pid_S000007066_Cid_C000019277"
      decimals="6"
      id="ixv-89492"
      unitRef="pure">-0.0000</oef:FeeWaiverOrReimbursementOverAssets>
    <oef:FeeWaiverOrReimbursementOverAssets
      contextRef="Pid_S000007066_Cid_C000150510"
      decimals="6"
      id="footnoteS000007066ATB-PROAOE_AC000150510_FW"
      unitRef="pure">-0.0004</oef:FeeWaiverOrReimbursementOverAssets>
    <oef:NetExpensesOverAssets
      contextRef="Pid_S000007066_Cid_C000019273"
      decimals="6"
      id="ixv-89494"
      unitRef="pure">0.0075</oef:NetExpensesOverAssets>
    <oef:NetExpensesOverAssets
      contextRef="Pid_S000007066_Cid_C000019276"
      decimals="6"
      id="ixv-89495"
      unitRef="pure">0.0075</oef:NetExpensesOverAssets>
    <oef:NetExpensesOverAssets
      contextRef="Pid_S000007066_Cid_C000019275"
      decimals="6"
      id="ixv-89496"
      unitRef="pure">0.0151</oef:NetExpensesOverAssets>
    <oef:NetExpensesOverAssets
      contextRef="Pid_S000007066_Cid_C000019277"
      decimals="6"
      id="ixv-89497"
      unitRef="pure">0.0050</oef:NetExpensesOverAssets>
    <oef:NetExpensesOverAssets
      contextRef="Pid_S000007066_Cid_C000150510"
      decimals="6"
      id="ixv-89498"
      unitRef="pure">0.0036</oef:NetExpensesOverAssets>
    <oef:FeeWaiverOrReimbursementOverAssetsDateOfTermination contextRef="Pid_S000007066_contentCd_ATB-PRO" id="ixv-5776">2026-12-31</oef:FeeWaiverOrReimbursementOverAssetsDateOfTermination>
    <oef:ExpenseExampleNarrativeTextBlock contextRef="Pid_S000007066_contentCd_ATB-PRO" id="ixv-5785">


     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_S000007066_Cid_C000019273"
      decimals="0"
      id="ixv-89499"
      unitRef="usd">474</oef:ExpenseExampleYear01>
    <oef:ExpenseExampleNoRedemptionYear01
      contextRef="Pid_S000007066_Cid_C000019273"
      decimals="0"
      id="ixv-89500"
      unitRef="usd">474</oef:ExpenseExampleNoRedemptionYear01>
    <oef:ExpenseExampleYear01
      contextRef="Pid_S000007066_Cid_C000019276"
      decimals="0"
      id="ixv-89501"
      unitRef="usd">474</oef:ExpenseExampleYear01>
    <oef:ExpenseExampleNoRedemptionYear01
      contextRef="Pid_S000007066_Cid_C000019276"
      decimals="0"
      id="ixv-89502"
      unitRef="usd">474</oef:ExpenseExampleNoRedemptionYear01>
    <oef:ExpenseExampleYear01
      contextRef="Pid_S000007066_Cid_C000019275"
      decimals="0"
      id="ixv-89503"
      unitRef="usd">254</oef:ExpenseExampleYear01>
    <oef:ExpenseExampleNoRedemptionYear01
      contextRef="Pid_S000007066_Cid_C000019275"
      decimals="0"
      id="ixv-89504"
      unitRef="usd">154</oef:ExpenseExampleNoRedemptionYear01>
    <oef:ExpenseExampleYear01
      contextRef="Pid_S000007066_Cid_C000019277"
      decimals="0"
      id="ixv-89505"
      unitRef="usd">51</oef:ExpenseExampleYear01>
    <oef:ExpenseExampleNoRedemptionYear01
      contextRef="Pid_S000007066_Cid_C000019277"
      decimals="0"
      id="ixv-89506"
      unitRef="usd">51</oef:ExpenseExampleNoRedemptionYear01>
    <oef:ExpenseExampleYear01
      contextRef="Pid_S000007066_Cid_C000150510"
      decimals="0"
      id="ixv-89507"
      unitRef="usd">37</oef:ExpenseExampleYear01>
    <oef:ExpenseExampleNoRedemptionYear01
      contextRef="Pid_S000007066_Cid_C000150510"
      decimals="0"
      id="ixv-89508"
      unitRef="usd">37</oef:ExpenseExampleNoRedemptionYear01>
    <oef:ExpenseExampleYear03
      contextRef="Pid_S000007066_Cid_C000019273"
      decimals="0"
      id="ixv-89509"
      unitRef="usd">630</oef:ExpenseExampleYear03>
    <oef:ExpenseExampleNoRedemptionYear03
      contextRef="Pid_S000007066_Cid_C000019273"
      decimals="0"
      id="ixv-89510"
      unitRef="usd">630</oef:ExpenseExampleNoRedemptionYear03>
    <oef:ExpenseExampleYear03
      contextRef="Pid_S000007066_Cid_C000019276"
      decimals="0"
      id="ixv-89511"
      unitRef="usd">630</oef:ExpenseExampleYear03>
    <oef:ExpenseExampleNoRedemptionYear03
      contextRef="Pid_S000007066_Cid_C000019276"
      decimals="0"
      id="ixv-89512"
      unitRef="usd">630</oef:ExpenseExampleNoRedemptionYear03>
    <oef:ExpenseExampleYear03
      contextRef="Pid_S000007066_Cid_C000019275"
      decimals="0"
      id="ixv-89513"
      unitRef="usd">477</oef:ExpenseExampleYear03>
    <oef:ExpenseExampleNoRedemptionYear03
      contextRef="Pid_S000007066_Cid_C000019275"
      decimals="0"
      id="ixv-89514"
      unitRef="usd">477</oef:ExpenseExampleNoRedemptionYear03>
    <oef:ExpenseExampleYear03
      contextRef="Pid_S000007066_Cid_C000019277"
      decimals="0"
      id="ixv-89515"
      unitRef="usd">160</oef:ExpenseExampleYear03>
    <oef:ExpenseExampleNoRedemptionYear03
      contextRef="Pid_S000007066_Cid_C000019277"
      decimals="0"
      id="ixv-89516"
      unitRef="usd">160</oef:ExpenseExampleNoRedemptionYear03>
    <oef:ExpenseExampleYear03
      contextRef="Pid_S000007066_Cid_C000150510"
      decimals="0"
      id="ixv-89517"
      unitRef="usd">123</oef:ExpenseExampleYear03>
    <oef:ExpenseExampleNoRedemptionYear03
      contextRef="Pid_S000007066_Cid_C000150510"
      decimals="0"
      id="ixv-89518"
      unitRef="usd">123</oef:ExpenseExampleNoRedemptionYear03>
    <oef:ExpenseExampleYear05
      contextRef="Pid_S000007066_Cid_C000019273"
      decimals="0"
      id="ixv-89519"
      unitRef="usd">800</oef:ExpenseExampleYear05>
    <oef:ExpenseExampleNoRedemptionYear05
      contextRef="Pid_S000007066_Cid_C000019273"
      decimals="0"
      id="ixv-89520"
      unitRef="usd">800</oef:ExpenseExampleNoRedemptionYear05>
    <oef:ExpenseExampleYear05
      contextRef="Pid_S000007066_Cid_C000019276"
      decimals="0"
      id="ixv-89521"
      unitRef="usd">800</oef:ExpenseExampleYear05>
    <oef:ExpenseExampleNoRedemptionYear05
      contextRef="Pid_S000007066_Cid_C000019276"
      decimals="0"
      id="ixv-89522"
      unitRef="usd">800</oef:ExpenseExampleNoRedemptionYear05>
    <oef:ExpenseExampleYear05
      contextRef="Pid_S000007066_Cid_C000019275"
      decimals="0"
      id="ixv-89523"
      unitRef="usd">824</oef:ExpenseExampleYear05>
    <oef:ExpenseExampleNoRedemptionYear05
      contextRef="Pid_S000007066_Cid_C000019275"
      decimals="0"
      id="ixv-89524"
      unitRef="usd">824</oef:ExpenseExampleNoRedemptionYear05>
    <oef:ExpenseExampleYear05
      contextRef="Pid_S000007066_Cid_C000019277"
      decimals="0"
      id="ixv-89525"
      unitRef="usd">280</oef:ExpenseExampleYear05>
    <oef:ExpenseExampleNoRedemptionYear05
      contextRef="Pid_S000007066_Cid_C000019277"
      decimals="0"
      id="ixv-89526"
      unitRef="usd">280</oef:ExpenseExampleNoRedemptionYear05>
    <oef:ExpenseExampleYear05
      contextRef="Pid_S000007066_Cid_C000150510"
      decimals="0"
      id="ixv-89527"
      unitRef="usd">219</oef:ExpenseExampleYear05>
    <oef:ExpenseExampleNoRedemptionYear05
      contextRef="Pid_S000007066_Cid_C000150510"
      decimals="0"
      id="ixv-89528"
      unitRef="usd">219</oef:ExpenseExampleNoRedemptionYear05>
    <oef:ExpenseExampleYear10
      contextRef="Pid_S000007066_Cid_C000019273"
      decimals="0"
      id="ixv-89529"
      unitRef="usd">1293</oef:ExpenseExampleYear10>
    <oef:ExpenseExampleNoRedemptionYear10
      contextRef="Pid_S000007066_Cid_C000019273"
      decimals="0"
      id="ixv-89530"
      unitRef="usd">1293</oef:ExpenseExampleNoRedemptionYear10>
    <oef:ExpenseExampleYear10
      contextRef="Pid_S000007066_Cid_C000019276"
      decimals="0"
      id="ixv-89531"
      unitRef="usd">1293</oef:ExpenseExampleYear10>
    <oef:ExpenseExampleNoRedemptionYear10
      contextRef="Pid_S000007066_Cid_C000019276"
      decimals="0"
      id="ixv-89532"
      unitRef="usd">1293</oef:ExpenseExampleNoRedemptionYear10>
    <oef:ExpenseExampleYear10
      contextRef="Pid_S000007066_Cid_C000019275"
      decimals="0"
      id="ixv-89533"
      unitRef="usd">1596</oef:ExpenseExampleYear10>
    <oef:ExpenseExampleNoRedemptionYear10
      contextRef="Pid_S000007066_Cid_C000019275"
      decimals="0"
      id="ixv-89534"
      unitRef="usd">1596</oef:ExpenseExampleNoRedemptionYear10>
    <oef:ExpenseExampleYear10
      contextRef="Pid_S000007066_Cid_C000019277"
      decimals="0"
      id="ixv-89535"
      unitRef="usd">628</oef:ExpenseExampleYear10>
    <oef:ExpenseExampleNoRedemptionYear10
      contextRef="Pid_S000007066_Cid_C000019277"
      decimals="0"
      id="ixv-89536"
      unitRef="usd">628</oef:ExpenseExampleNoRedemptionYear10>
    <oef:ExpenseExampleYear10
      contextRef="Pid_S000007066_Cid_C000150510"
      decimals="0"
      id="ixv-89537"
      unitRef="usd">500</oef:ExpenseExampleYear10>
    <oef:ExpenseExampleNoRedemptionYear10
      contextRef="Pid_S000007066_Cid_C000150510"
      decimals="0"
      id="ixv-89538"
      unitRef="usd">500</oef:ExpenseExampleNoRedemptionYear10>
    <oef:PortfolioTurnoverHeading contextRef="Pid_S000007066_contentCd_ATB-PRO" id="ixv-6093">


     Portfolio Turnover


   </oef:PortfolioTurnoverHeading>
    <oef:PortfolioTurnoverTextBlock contextRef="Pid_S000007066_contentCd_ATB-PRO" id="ixv-6098">


     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



       211


     % of the average value of its portfolio.


   </oef:PortfolioTurnoverTextBlock>
    <oef:PortfolioTurnoverRate
      contextRef="Pid_S000007066_contentCd_ATB-PRO"
      decimals="4"
      id="ixv-89539"
      unitRef="pure">2.11</oef:PortfolioTurnoverRate>
    <oef:StrategyHeading contextRef="Pid_S000007066_contentCd_ATB-PRO" id="ixv-6107">


     Principal Investment Strategies


   </oef:StrategyHeading>
    <oef:StrategyNarrativeTextBlock contextRef="Pid_S000007066_contentCd_ATB-PRO" id="ixv-6112">




        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.
      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_S000007066_contentCd_ATB-PRO_RiskMember_InterestRateChangesMember"
      id="ixv-6154">



      Interest Rate Changes.

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

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000007066_contentCd_ATB-PRO_RiskMember_ForeignExposureMember"
      id="ixv-6163">



      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_S000007066_contentCd_ATB-PRO_RiskMember_PrepaymentMember"
      id="ixv-6174">



      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_S000007066_contentCd_ATB-PRO_RiskMember_IssuerSpecificChangesMember"
      id="ixv-6183">



      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_S000007066_contentCd_ATB-PRO_RiskMember_LeverageRiskMember"
      id="ixv-6202">



      Leverage Risk.

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

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000007066_contentCd_ATB-PRO_RiskMember_HighPortfolioTurnoverMember"
      id="ixv-6211">



      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_S000007066_contentCd_ATB-PRO_RiskMember_RiskNotInsuredDepositoryInstitutionMember"
      id="ixv-6221">


     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_S000007066_contentCd_ATB-PRO_RiskMember_RiskLoseMoneyMember"
      id="ixv-6229">


     &#160;

     You could lose money by investing in the fund.


   </oef:RiskTextBlock>
    <oef:BarChartAndPerformanceTableHeading contextRef="Pid_S000007066_contentCd_ATB-PRO" id="ixv-6238">


     Performance


   </oef:BarChartAndPerformanceTableHeading>
    <oef:PerformanceNarrativeTextBlock contextRef="Pid_S000007066_contentCd_ATB-PRO" id="ixv-6243">



       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.401k.com and log in (plan accounts) or institutional.fidelity.com (all other accounts)


     for more recent performance information.

   </oef:PerformanceNarrativeTextBlock>
    <oef:PerformanceInformationIllustratesVariabilityOfReturns contextRef="Pid_S000007066_contentCd_ATB-PRO" id="ixv-6249">

      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_S000007066_contentCd_ATB-PRO" id="ixv-6263">

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

     </oef:PerformancePastDoesNotIndicateFuture>
    <oef:PerformanceAvailabilityWebSiteAddress contextRef="Pid_S000007066_contentCd_ATB-PRO" id="ixv-6269">

      www.401k.com and log in (plan accounts) or institutional.fidelity.com (all other accounts)
     </oef:PerformanceAvailabilityWebSiteAddress>
    <oef:BarChartHeading contextRef="Pid_S000007066_contentCd_ATB-PRO" id="ixv-6274">


     Year-by-Year Returns

   </oef:BarChartHeading>
    <oef:BarChartNarrativeTextBlock contextRef="Pid_S000007066_contentCd_ATB-PRO" id="ixv-6278">




      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_S000007066_contentCd_ATB-PRO" id="ixv-6281">

      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_S000007066_Cid_C000019273_2015"
      decimals="INF"
      id="ixv-89540"
      unitRef="pure">-0.0073</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000007066_Cid_C000019273_2016"
      decimals="INF"
      id="ixv-89541"
      unitRef="pure">0.0553</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000007066_Cid_C000019273_2017"
      decimals="INF"
      id="ixv-89542"
      unitRef="pure">0.0397</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000007066_Cid_C000019273_2018"
      decimals="INF"
      id="ixv-89543"
      unitRef="pure">-0.0107</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000007066_Cid_C000019273_2019"
      decimals="INF"
      id="ixv-89544"
      unitRef="pure">0.0954</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000007066_Cid_C000019273_2020"
      decimals="INF"
      id="ixv-89545"
      unitRef="pure">0.0901</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000007066_Cid_C000019273_2021"
      decimals="INF"
      id="ixv-89546"
      unitRef="pure">-0.0030</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000007066_Cid_C000019273_2022"
      decimals="INF"
      id="ixv-89547"
      unitRef="pure">-0.1315</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000007066_Cid_C000019273_2023"
      decimals="INF"
      id="ixv-89548"
      unitRef="pure">0.0691</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000007066_Cid_C000019273_2024"
      decimals="INF"
      id="ixv-89549"
      unitRef="pure">0.0219</oef:AnnlRtrPct>
    <oef:HighestQuarterlyReturnLabel contextRef="Pid_S000007066_contentCd_ATB-PRO" id="ixv-6395">
          &#160;&#160;&#160;Highest Quarter Return
        </oef:HighestQuarterlyReturnLabel>
    <oef:BarChartHighestQuarterlyReturn
      contextRef="Pid_S000007066_contentCd_ATB-PRO"
      decimals="4"
      id="ixv-89550"
      unitRef="pure">0.0686</oef:BarChartHighestQuarterlyReturn>
    <oef:BarChartHighestQuarterlyReturnDate contextRef="Pid_S000007066_contentCd_ATB-PRO" id="ixv-6405">2023-12-31</oef:BarChartHighestQuarterlyReturnDate>
    <oef:LowestQuarterlyReturnLabel contextRef="Pid_S000007066_contentCd_ATB-PRO" id="ixv-6410">
          &#160;&#160;&#160;Lowest Quarter Return
        </oef:LowestQuarterlyReturnLabel>
    <oef:BarChartLowestQuarterlyReturn
      contextRef="Pid_S000007066_contentCd_ATB-PRO"
      decimals="4"
      id="ixv-89551"
      unitRef="pure">-0.0625</oef:BarChartLowestQuarterlyReturn>
    <oef:BarChartLowestQuarterlyReturnDate contextRef="Pid_S000007066_contentCd_ATB-PRO" id="ixv-6421">2022-06-30</oef:BarChartLowestQuarterlyReturnDate>
    <oef:YearToDateReturnLabel contextRef="Pid_S000007066_contentCd_ATB-PRO" id="ixv-6426">
          &#160;&#160;&#160;Year-to-Date Return
        </oef:YearToDateReturnLabel>
    <oef:BarChartYearToDateReturn
      contextRef="Pid_S000007066_contentCd_ATB-PRO"
      decimals="4"
      id="ixv-89552"
      unitRef="pure">0.0623</oef:BarChartYearToDateReturn>
    <oef:BarChartYearToDateReturnDate contextRef="Pid_S000007066_contentCd_ATB-PRO" id="ixv-6436">2025-09-30</oef:BarChartYearToDateReturnDate>
    <oef:PerformanceTableHeading contextRef="Pid_S000007066_contentCd_ATB-PRO" id="ixv-6441">


     Average Annual Returns


   </oef:PerformanceTableHeading>
    <oef:PerformanceTableNarrativeTextBlock contextRef="Pid_S000007066_contentCd_ATB-PRO" id="ixv-6446">




      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_S000007066_contentCd_ATB-PRO" id="ixv-6449">

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

     </oef:PerformanceTableDoesReflectSalesLoads>
    <oef:PerformanceTableUsesHighestFederalRate contextRef="Pid_S000007066_contentCd_ATB-PRO" id="ixv-6454">

      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_S000007066_contentCd_ATB-PRO" id="ixv-6459">

      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_S000007066_contentCd_ATB-PRO" id="ixv-6465">

      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_S000007066_contentCd_ATB-PRO" id="ixv-6469">

      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_S000007066_Cid_C000019273_ReturnBeforeTaxes_01"
      id="ixv-6502">
         Return Before Taxes
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007066_Cid_C000019273_ReturnBeforeTaxes_01"
      decimals="4"
      id="ixv-89553"
      unitRef="pure">-0.0190</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007066_Cid_C000019273_ReturnBeforeTaxes_05"
      decimals="4"
      id="ixv-89554"
      unitRef="pure">-0.0020</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007066_Cid_C000019273_ReturnBeforeTaxes_10"
      decimals="4"
      id="ixv-89555"
      unitRef="pure">0.0157</oef:AvgAnnlRtrPct>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000007066_Cid_C000019273_AfterTaxesOnDistributions_01"
      id="ixv-6521">
         Return After Taxes on Distributions
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007066_Cid_C000019273_AfterTaxesOnDistributions_01"
      decimals="4"
      id="ixv-89556"
      unitRef="pure">-0.0344</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007066_Cid_C000019273_AfterTaxesOnDistributions_05"
      decimals="4"
      id="ixv-89557"
      unitRef="pure">-0.0158</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007066_Cid_C000019273_AfterTaxesOnDistributions_10"
      decimals="4"
      id="ixv-89558"
      unitRef="pure">0.0026</oef:AvgAnnlRtrPct>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000007066_Cid_C000019273_AfterTaxesOnDistributionsAndSales_01"
      id="ixv-6539">
          Return After Taxes on Distributions and Sale of Fund Shares
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007066_Cid_C000019273_AfterTaxesOnDistributionsAndSales_01"
      decimals="4"
      id="ixv-89559"
      unitRef="pure">-0.0102</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007066_Cid_C000019273_AfterTaxesOnDistributionsAndSales_05"
      decimals="4"
      id="ixv-89560"
      unitRef="pure">-0.0068</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007066_Cid_C000019273_AfterTaxesOnDistributionsAndSales_10"
      decimals="4"
      id="ixv-89561"
      unitRef="pure">0.0066</oef:AvgAnnlRtrPct>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000007066_Cid_C000019276_ReturnBeforeTaxes_01"
      id="ixv-6556">
         Return Before Taxes
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007066_Cid_C000019276_ReturnBeforeTaxes_01"
      decimals="4"
      id="ixv-89562"
      unitRef="pure">-0.0190</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007066_Cid_C000019276_ReturnBeforeTaxes_05"
      decimals="4"
      id="ixv-89563"
      unitRef="pure">-0.0021</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007066_Cid_C000019276_ReturnBeforeTaxes_10"
      decimals="4"
      id="ixv-89564"
      unitRef="pure">0.0156</oef:AvgAnnlRtrPct>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000007066_Cid_C000019275_ReturnBeforeTaxes_01"
      id="ixv-6573">
         Return Before Taxes
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007066_Cid_C000019275_ReturnBeforeTaxes_01"
      decimals="4"
      id="ixv-89565"
      unitRef="pure">0.0043</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007066_Cid_C000019275_ReturnBeforeTaxes_05"
      decimals="4"
      id="ixv-89566"
      unitRef="pure">-0.0017</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007066_Cid_C000019275_ReturnBeforeTaxes_10"
      decimals="4"
      id="ixv-89567"
      unitRef="pure">0.0136</oef:AvgAnnlRtrPct>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000007066_Cid_C000019277_ReturnBeforeTaxes_01"
      id="ixv-6589">
         Return Before Taxes
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007066_Cid_C000019277_ReturnBeforeTaxes_01"
      decimals="4"
      id="ixv-89568"
      unitRef="pure">0.0244</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007066_Cid_C000019277_ReturnBeforeTaxes_05"
      decimals="4"
      id="ixv-89569"
      unitRef="pure">0.0086</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007066_Cid_C000019277_ReturnBeforeTaxes_10"
      decimals="4"
      id="ixv-89570"
      unitRef="pure">0.0224</oef:AvgAnnlRtrPct>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000007066_Cid_C000150510_ReturnBeforeTaxes_01"
      id="ixv-6604">
         Return Before Taxes
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007066_Cid_C000150510_ReturnBeforeTaxes_01"
      decimals="4"
      id="ixv-89571"
      unitRef="pure">0.0258</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007066_Cid_C000150510_ReturnBeforeTaxes_05"
      decimals="4"
      id="ixv-89572"
      unitRef="pure">0.0100</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007066_Cid_C000150510_ReturnBeforeTaxes_10"
      decimals="4"
      id="ixv-89573"
      unitRef="pure">0.0237</oef:AvgAnnlRtrPct>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000007066_Indexid_LB001_contentCd_ATB-PRO_01"
      id="ixv-6618">
         Bloomberg U.S. Aggregate Bond Index
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007066_Indexid_LB001_contentCd_ATB-PRO_01"
      decimals="4"
      id="ixv-89574"
      unitRef="pure">0.0125</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007066_Indexid_LB001_contentCd_ATB-PRO_05"
      decimals="4"
      id="ixv-89575"
      unitRef="pure">-0.0033</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007066_Indexid_LB001_contentCd_ATB-PRO_10"
      decimals="4"
      id="ixv-89576"
      unitRef="pure">0.0135</oef:AvgAnnlRtrPct>
    <oef:RiskReturnHeading
      contextRef="Pid_S000062811_contentCd_XGB-PRO"
      id="ixv-13205">


     Fund Summary

     Fund:
     Fidelity&#xae; Series Government Bond Index Fund

   </oef:RiskReturnHeading>
    <oef:ObjectiveHeading
      contextRef="Pid_S000062811_contentCd_XGB-PRO"
      id="ixv-13214">


     Investment Objective


   </oef:ObjectiveHeading>
    <oef:ObjectivePrimaryTextBlock
      contextRef="Pid_S000062811_contentCd_XGB-PRO"
      id="ixv-13219">


     Fidelity&#xae; Series Government Bond Index Fund seeks a high level of current income.


   </oef:ObjectivePrimaryTextBlock>
    <oef:ExpenseHeading
      contextRef="Pid_S000062811_contentCd_XGB-PRO"
      id="ixv-13224">


     Fee Table


   </oef:ExpenseHeading>
    <oef:ExpenseNarrativeTextBlock
      contextRef="Pid_S000062811_contentCd_XGB-PRO"
      id="ixv-13230">


     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_S000062811_contentCd_XGB-PRO"
      id="ixv-13240">


     Shareholder fees


   </oef:ShareholderFeesCaption>
    <oef:ShareholderFeeOther
      contextRef="Pid_S000062811_contentCd_XGB-PRO"
      decimals="0"
      id="ixv-89577"
      unitRef="usd">0</oef:ShareholderFeeOther>
    <oef:OperatingExpensesCaption
      contextRef="Pid_S000062811_contentCd_XGB-PRO"
      id="ixv-13255">


     Annual Operating Expenses


   </oef:OperatingExpensesCaption>
    <oef:ManagementFeesOverAssets
      contextRef="Pid_S000062811_Cid_C000203458"
      decimals="6"
      id="ixv-89578"
      unitRef="pure">0.0000</oef:ManagementFeesOverAssets>
    <oef:DistributionAndService12b1FeesOverAssets
      contextRef="Pid_S000062811_Cid_C000203458"
      decimals="6"
      id="ixv-89579"
      unitRef="pure">0</oef:DistributionAndService12b1FeesOverAssets>
    <oef:OtherExpensesOverAssets
      contextRef="Pid_S000062811_Cid_C000203458"
      decimals="6"
      id="ixv-89580"
      unitRef="pure">0.0000</oef:OtherExpensesOverAssets>
    <oef:ExpensesOverAssets
      contextRef="Pid_S000062811_Cid_C000203458"
      decimals="6"
      id="ixv-89581"
      unitRef="pure">0.0000</oef:ExpensesOverAssets>
    <oef:ExpenseExampleNarrativeTextBlock
      contextRef="Pid_S000062811_contentCd_XGB-PRO"
      id="ixv-13302">


     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_S000062811_Cid_C000203458"
      decimals="0"
      id="ixv-89582"
      unitRef="usd">0</oef:ExpenseExampleYear01>
    <oef:ExpenseExampleYear03
      contextRef="Pid_S000062811_Cid_C000203458"
      decimals="0"
      id="ixv-89583"
      unitRef="usd">0</oef:ExpenseExampleYear03>
    <oef:ExpenseExampleYear05
      contextRef="Pid_S000062811_Cid_C000203458"
      decimals="0"
      id="ixv-89584"
      unitRef="usd">0</oef:ExpenseExampleYear05>
    <oef:ExpenseExampleYear10
      contextRef="Pid_S000062811_Cid_C000203458"
      decimals="0"
      id="ixv-89585"
      unitRef="usd">0</oef:ExpenseExampleYear10>
    <oef:PortfolioTurnoverHeading
      contextRef="Pid_S000062811_contentCd_XGB-PRO"
      id="ixv-13359">


     Portfolio Turnover


   </oef:PortfolioTurnoverHeading>
    <oef:PortfolioTurnoverTextBlock
      contextRef="Pid_S000062811_contentCd_XGB-PRO"
      id="ixv-13364">


     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



       23


     % of the average value of its portfolio.


   </oef:PortfolioTurnoverTextBlock>
    <oef:PortfolioTurnoverRate
      contextRef="Pid_S000062811_contentCd_XGB-PRO"
      decimals="4"
      id="ixv-89586"
      unitRef="pure">0.23</oef:PortfolioTurnoverRate>
    <oef:StrategyHeading
      contextRef="Pid_S000062811_contentCd_XGB-PRO"
      id="ixv-13373">


     Principal Investment Strategies


   </oef:StrategyHeading>
    <oef:StrategyNarrativeTextBlock
      contextRef="Pid_S000062811_contentCd_XGB-PRO"
      id="ixv-13378">




        Normally investing at least 80% of assets in securities included in the Bloomberg U.S. Government Bond Index.

     The Bloomberg U.S. Government Bond Index is a market value-weighted index of U.S. Government fixed-rate debt issues with maturities of one year or more.
     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 statistical sampling techniques based on duration, maturity, interest rate sensitivity, security structure, and credit quality to attempt to replicate the returns of the Bloomberg U.S. Government Bond Index using a smaller number of securities.


   </oef:StrategyNarrativeTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000062811_contentCd_XGB-PRO_RiskMember_InterestRateChangesMember"
      id="ixv-13396">



      Interest Rate Changes.

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

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000062811_contentCd_XGB-PRO_RiskMember_PrepaymentMember"
      id="ixv-13405">



      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_S000062811_contentCd_XGB-PRO_RiskMember_IssuerSpecificChangesMember"
      id="ixv-13414">



      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_S000062811_contentCd_XGB-PRO_RiskMember_USGovernmentObligationsRiskMember"
      id="ixv-13429">



      U.S. Government Obligations Risk.

     Certain securities in which the fund may invest, including securities issued by certain U.S. Government agencies and U.S. Government sponsored enterprises, are not guaranteed by the U.S. Government or supported by the full faith and credit of the United States.

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000062811_contentCd_XGB-PRO_RiskMember_CorrelationToIndexMember"
      id="ixv-13438">



      Correlation to Index.

     The performance of the fund and its underlying index may vary somewhat due to factors such as fees and expenses of the fund, transaction costs, sample selection, regulatory restrictions, and timing differences associated with additions to and deletions from the index. Errors in the construction or calculation of the index may occur from time to time and may not be identified and corrected for some period of time, which may have an adverse impact on the fund and its shareholders.

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000062811_contentCd_XGB-PRO_RiskMember_PassiveManagementRiskMember"
      id="ixv-13447">



      Passive Management Risk.

     The fund is managed with a passive investment strategy, attempting to track the performance of an unmanaged index of securities, regardless of the current or projected performance of the fund's index or of the actual securities included in the index. This differs from an actively managed fund, which typically seeks to outperform a benchmark index. As a result, the fund's performance could be lower than actively managed funds that may shift their portfolio assets to take advantage of market opportunities or lessen the impact of a market decline or a decline in the value of one or more issuers.
     The fund will be concentrated to approximately the same extent that the fund's index concentrates in the securities of issuers in a particular industry or group of industries.



   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000062811_contentCd_XGB-PRO_RiskMember_RiskNotInsuredDepositoryInstitutionMember"
      id="ixv-13459">


     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_S000062811_contentCd_XGB-PRO_RiskMember_RiskLoseMoneyMember"
      id="ixv-13467">


     &#160;

     You could lose money by investing in the fund.


   </oef:RiskTextBlock>
    <oef:BarChartAndPerformanceTableHeading
      contextRef="Pid_S000062811_contentCd_XGB-PRO"
      id="ixv-13476">


     Performance


   </oef:BarChartAndPerformanceTableHeading>
    <oef:PerformanceNarrativeTextBlock
      contextRef="Pid_S000062811_contentCd_XGB-PRO"
      id="ixv-13481">



       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, if applicable.
     Visit



      www.fidelity.com


     for more recent performance information.

   </oef:PerformanceNarrativeTextBlock>
    <oef:PerformanceInformationIllustratesVariabilityOfReturns
      contextRef="Pid_S000062811_contentCd_XGB-PRO"
      id="ixv-13487">

      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_S000062811_contentCd_XGB-PRO"
      id="ixv-13496">

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

     </oef:PerformancePastDoesNotIndicateFuture>
    <oef:PerformanceAvailabilityWebSiteAddress
      contextRef="Pid_S000062811_contentCd_XGB-PRO"
      id="ixv-13504">

      www.fidelity.com
     </oef:PerformanceAvailabilityWebSiteAddress>
    <oef:BarChartHeading
      contextRef="Pid_S000062811_contentCd_XGB-PRO"
      id="ixv-13509">


     Year-by-Year Returns

   </oef:BarChartHeading>
    <oef:AnnlRtrPct
      contextRef="Pid_S000062811_Cid_C000203458_2019"
      decimals="INF"
      id="ixv-89587"
      unitRef="pure">0.0663</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000062811_Cid_C000203458_2020"
      decimals="INF"
      id="ixv-89588"
      unitRef="pure">0.0798</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000062811_Cid_C000203458_2021"
      decimals="INF"
      id="ixv-89589"
      unitRef="pure">-0.0234</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000062811_Cid_C000203458_2022"
      decimals="INF"
      id="ixv-89590"
      unitRef="pure">-0.1236</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000062811_Cid_C000203458_2023"
      decimals="INF"
      id="ixv-89591"
      unitRef="pure">0.0430</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000062811_Cid_C000203458_2024"
      decimals="INF"
      id="ixv-89592"
      unitRef="pure">0.0071</oef:AnnlRtrPct>
    <oef:HighestQuarterlyReturnLabel
      contextRef="Pid_S000062811_contentCd_XGB-PRO"
      id="ixv-13608">
          &#160;&#160;&#160;Highest Quarter Return
        </oef:HighestQuarterlyReturnLabel>
    <oef:BarChartHighestQuarterlyReturn
      contextRef="Pid_S000062811_contentCd_XGB-PRO"
      decimals="4"
      id="ixv-89593"
      unitRef="pure">0.0845</oef:BarChartHighestQuarterlyReturn>
    <oef:BarChartHighestQuarterlyReturnDate
      contextRef="Pid_S000062811_contentCd_XGB-PRO"
      id="ixv-13618">2020-03-31</oef:BarChartHighestQuarterlyReturnDate>
    <oef:LowestQuarterlyReturnLabel
      contextRef="Pid_S000062811_contentCd_XGB-PRO"
      id="ixv-13623">
          &#160;&#160;&#160;Lowest Quarter Return
        </oef:LowestQuarterlyReturnLabel>
    <oef:BarChartLowestQuarterlyReturn
      contextRef="Pid_S000062811_contentCd_XGB-PRO"
      decimals="4"
      id="ixv-89594"
      unitRef="pure">-0.0539</oef:BarChartLowestQuarterlyReturn>
    <oef:BarChartLowestQuarterlyReturnDate
      contextRef="Pid_S000062811_contentCd_XGB-PRO"
      id="ixv-13634">2022-03-31</oef:BarChartLowestQuarterlyReturnDate>
    <oef:YearToDateReturnLabel
      contextRef="Pid_S000062811_contentCd_XGB-PRO"
      id="ixv-13639">
          &#160;&#160;&#160;Year-to-Date Return
        </oef:YearToDateReturnLabel>
    <oef:BarChartYearToDateReturn
      contextRef="Pid_S000062811_contentCd_XGB-PRO"
      decimals="4"
      id="ixv-89595"
      unitRef="pure">0.0544</oef:BarChartYearToDateReturn>
    <oef:BarChartYearToDateReturnDate
      contextRef="Pid_S000062811_contentCd_XGB-PRO"
      id="ixv-13649">2025-09-30</oef:BarChartYearToDateReturnDate>
    <oef:PerformanceTableHeading
      contextRef="Pid_S000062811_contentCd_XGB-PRO"
      id="ixv-13654">


     Average Annual Returns


   </oef:PerformanceTableHeading>
    <oef:PerformanceTableNarrativeTextBlock
      contextRef="Pid_S000062811_contentCd_XGB-PRO"
      id="ixv-13659">




      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_S000062811_contentCd_XGB-PRO"
      id="ixv-13662">

      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_S000062811_contentCd_XGB-PRO"
      id="ixv-13669">

      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_S000062811_contentCd_XGB-PRO"
      id="ixv-13674">

      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_S000062811_Cid_C000203458_ReturnBeforeTaxes_01"
      id="ixv-13720">
         Return Before Taxes
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000062811_Cid_C000203458_ReturnBeforeTaxes_01"
      decimals="4"
      id="ixv-89596"
      unitRef="pure">0.0071</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000062811_Cid_C000203458_ReturnBeforeTaxes_05"
      decimals="4"
      id="ixv-89597"
      unitRef="pure">-0.0059</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000062811_Cid_C000203458_ReturnBeforeTaxes_AverageAnnualReturnSinceInception"
      decimals="4"
      id="footnoteXGB-PROS000062811AAR_A_RBT_loc"
      unitRef="pure">0.0082</oef:AvgAnnlRtrPct>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000062811_Cid_C000203458_AfterTaxesOnDistributions_01"
      id="ixv-13737">
         Return After Taxes on Distributions
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000062811_Cid_C000203458_AfterTaxesOnDistributions_01"
      decimals="4"
      id="ixv-89599"
      unitRef="pure">-0.0056</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000062811_Cid_C000203458_AfterTaxesOnDistributions_05"
      decimals="4"
      id="ixv-89600"
      unitRef="pure">-0.0152</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000062811_Cid_C000203458_AfterTaxesOnDistributions_AverageAnnualReturnSinceInception"
      decimals="4"
      id="footnoteXGB-PROS000062811AAR_A_ATD_loc"
      unitRef="pure">-0.0015</oef:AvgAnnlRtrPct>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000062811_Cid_C000203458_AfterTaxesOnDistributionsAndSales_01"
      id="ixv-13756">
         Return After Taxes on Distributions and Sale of Fund Shares
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000062811_Cid_C000203458_AfterTaxesOnDistributionsAndSales_01"
      decimals="4"
      id="ixv-89602"
      unitRef="pure">0.0051</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000062811_Cid_C000203458_AfterTaxesOnDistributionsAndSales_05"
      decimals="4"
      id="ixv-89603"
      unitRef="pure">-0.0080</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000062811_Cid_C000203458_AfterTaxesOnDistributionsAndSales_AverageAnnualReturnSinceInception"
      decimals="4"
      id="footnoteXGB-PROS000062811AAR_A_ATDS_loc"
      unitRef="pure">0.0025</oef:AvgAnnlRtrPct>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000062811_Indexid_LB003_contentCd_XGB-PRO_01"
      id="ixv-13774">
         Bloomberg U.S. Government Bond Index
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000062811_Indexid_LB003_contentCd_XGB-PRO_01"
      decimals="4"
      id="ixv-89605"
      unitRef="pure">0.0062</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000062811_Indexid_LB003_contentCd_XGB-PRO_05"
      decimals="4"
      id="ixv-89606"
      unitRef="pure">-0.0063</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000062811_Indexid_LB003_contentCd_XGB-PRO_AverageAnnualReturnSinceInception"
      decimals="4"
      id="ixv-89607"
      unitRef="pure">0.0082</oef:AvgAnnlRtrPct>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000062811_Indexid_LB001_contentCd_XGB-PRO_01"
      id="ixv-13800">
         Bloomberg U.S. Aggregate Bond Index
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000062811_Indexid_LB001_contentCd_XGB-PRO_01"
      decimals="4"
      id="ixv-89608"
      unitRef="pure">0.0125</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000062811_Indexid_LB001_contentCd_XGB-PRO_05"
      decimals="4"
      id="ixv-89609"
      unitRef="pure">-0.0033</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000062811_Indexid_LB001_contentCd_XGB-PRO_AverageAnnualReturnSinceInception"
      decimals="4"
      id="ixv-89610"
      unitRef="pure">0.0124</oef:AvgAnnlRtrPct>
    <oef:AnnualReturnInceptionDate contextRef="Pid_S000062811_Cid_C000203458" id="ixv-13842">2018-08-17</oef:AnnualReturnInceptionDate>
    <oef:RiskReturnHeading
      contextRef="Pid_S000007069_contentCd_AGVT-PRO"
      id="ixv-15468">


     Fund Summary

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

   </oef:RiskReturnHeading>
    <oef:ObjectiveHeading
      contextRef="Pid_S000007069_contentCd_AGVT-PRO"
      id="ixv-15483">


     Investment Objective


   </oef:ObjectiveHeading>
    <oef:ObjectivePrimaryTextBlock
      contextRef="Pid_S000007069_contentCd_AGVT-PRO"
      id="ixv-15488">


     Fidelity&#xae; Government Income Fund seeks a high level of current income, consistent with preservation of principal.


   </oef:ObjectivePrimaryTextBlock>
    <oef:ExpenseHeading
      contextRef="Pid_S000007069_contentCd_AGVT-PRO"
      id="ixv-15493">


     Fee Table


   </oef:ExpenseHeading>
    <oef:ExpenseNarrativeTextBlock
      contextRef="Pid_S000007069_contentCd_AGVT-PRO"
      id="ixv-15499">


     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 33 of the prospectus



     and in

     the sales charge

     waiver appendix to

     the prospectus.

   </oef:ExpenseNarrativeTextBlock>
    <oef:ExpenseBreakpointDiscounts
      contextRef="Pid_S000007069_contentCd_AGVT-PRO"
      id="ixv-15505">

      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 33 of the prospectus

     </oef:ExpenseBreakpointDiscounts>
    <oef:ExpenseBreakpointMinimumInvestmentRequiredAmount
      contextRef="Pid_S000007069_contentCd_AGVT-PRO"
      decimals="0"
      id="ixv-89611"
      unitRef="usd">50000</oef:ExpenseBreakpointMinimumInvestmentRequiredAmount>
    <oef:ShareholderFeesCaption
      contextRef="Pid_S000007069_contentCd_AGVT-PRO"
      id="ixv-15526">


     Shareholder fees


   </oef:ShareholderFeesCaption>
    <oef:MaximumCumulativeSalesChargeOverOfferingPrice
      contextRef="Pid_S000007069_Cid_C000038098"
      decimals="4"
      id="ixv-89612"
      unitRef="pure">0.0400</oef:MaximumCumulativeSalesChargeOverOfferingPrice>
    <oef:MaximumCumulativeSalesChargeOverOfferingPrice
      contextRef="Pid_S000007069_Cid_C000038101"
      decimals="4"
      id="ixv-89613"
      unitRef="pure">0.0400</oef:MaximumCumulativeSalesChargeOverOfferingPrice>
    <oef:MaximumCumulativeSalesChargeOverOfferingPrice
      contextRef="Pid_S000007069_Cid_C000038100"
      decimals="4"
      id="ixv-89614"
      unitRef="pure">0</oef:MaximumCumulativeSalesChargeOverOfferingPrice>
    <oef:MaximumCumulativeSalesChargeOverOfferingPrice
      contextRef="Pid_S000007069_Cid_C000038102"
      decimals="4"
      id="ixv-89615"
      unitRef="pure">0</oef:MaximumCumulativeSalesChargeOverOfferingPrice>
    <oef:MaximumCumulativeSalesChargeOverOfferingPrice
      contextRef="Pid_S000007069_Cid_C000205069"
      decimals="4"
      id="ixv-89616"
      unitRef="pure">0</oef:MaximumCumulativeSalesChargeOverOfferingPrice>
    <oef:MaximumDeferredSalesChargeOverOther
      contextRef="Pid_S000007069_Cid_C000038098"
      decimals="4"
      id="footnoteAGVT-PROS000007069SHF_AC000038098"
      unitRef="pure">0</oef:MaximumDeferredSalesChargeOverOther>
    <oef:MaximumDeferredSalesChargeOverOther
      contextRef="Pid_S000007069_Cid_C000038101"
      decimals="4"
      id="footnoteAGVT-PROS000007069SHF_AC000038101"
      unitRef="pure">0</oef:MaximumDeferredSalesChargeOverOther>
    <oef:MaximumDeferredSalesChargeOverOther
      contextRef="Pid_S000007069_Cid_C000038100"
      decimals="4"
      id="footnoteAGVT-PROS000007069SHF_BC000038100"
      unitRef="pure">0.0100</oef:MaximumDeferredSalesChargeOverOther>
    <oef:MaximumDeferredSalesChargeOverOther
      contextRef="Pid_S000007069_Cid_C000038102"
      decimals="4"
      id="ixv-89620"
      unitRef="pure">0</oef:MaximumDeferredSalesChargeOverOther>
    <oef:MaximumDeferredSalesChargeOverOther
      contextRef="Pid_S000007069_Cid_C000205069"
      decimals="4"
      id="ixv-89621"
      unitRef="pure">0</oef:MaximumDeferredSalesChargeOverOther>
    <oef:ExpensesDeferredChargesTextBlock
      contextRef="Pid_S000007069_contentCd_AGVT-PRO"
      id="ixv-15632">

      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_S000007069_Cid_C000038100" id="ixv-15642">

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

     </oef:ExpensesDeferredChargesTextBlock>
    <oef:OperatingExpensesCaption
      contextRef="Pid_S000007069_contentCd_AGVT-PRO"
      id="ixv-15647">


     Annual Operating Expenses


   </oef:OperatingExpensesCaption>
    <oef:ManagementFeesOverAssets
      contextRef="Pid_S000007069_Cid_C000038098"
      decimals="6"
      id="ixv-89622"
      unitRef="pure">0.0028</oef:ManagementFeesOverAssets>
    <oef:ManagementFeesOverAssets
      contextRef="Pid_S000007069_Cid_C000038101"
      decimals="6"
      id="ixv-89623"
      unitRef="pure">0.0028</oef:ManagementFeesOverAssets>
    <oef:ManagementFeesOverAssets
      contextRef="Pid_S000007069_Cid_C000038100"
      decimals="6"
      id="ixv-89624"
      unitRef="pure">0.0028</oef:ManagementFeesOverAssets>
    <oef:ManagementFeesOverAssets
      contextRef="Pid_S000007069_Cid_C000038102"
      decimals="6"
      id="ixv-89625"
      unitRef="pure">0.0028</oef:ManagementFeesOverAssets>
    <oef:ManagementFeesOverAssets
      contextRef="Pid_S000007069_Cid_C000205069"
      decimals="6"
      id="ixv-89626"
      unitRef="pure">0.0028</oef:ManagementFeesOverAssets>
    <oef:DistributionAndService12b1FeesOverAssets
      contextRef="Pid_S000007069_Cid_C000038098"
      decimals="6"
      id="ixv-89627"
      unitRef="pure">0.0025</oef:DistributionAndService12b1FeesOverAssets>
    <oef:DistributionAndService12b1FeesOverAssets
      contextRef="Pid_S000007069_Cid_C000038101"
      decimals="6"
      id="ixv-89628"
      unitRef="pure">0.0025</oef:DistributionAndService12b1FeesOverAssets>
    <oef:DistributionAndService12b1FeesOverAssets
      contextRef="Pid_S000007069_Cid_C000038100"
      decimals="6"
      id="ixv-89629"
      unitRef="pure">0.0100</oef:DistributionAndService12b1FeesOverAssets>
    <oef:DistributionAndService12b1FeesOverAssets
      contextRef="Pid_S000007069_Cid_C000038102"
      decimals="6"
      id="ixv-89630"
      unitRef="pure">0</oef:DistributionAndService12b1FeesOverAssets>
    <oef:DistributionAndService12b1FeesOverAssets
      contextRef="Pid_S000007069_Cid_C000205069"
      decimals="6"
      id="ixv-89631"
      unitRef="pure">0</oef:DistributionAndService12b1FeesOverAssets>
    <oef:OtherExpensesOverAssets
      contextRef="Pid_S000007069_Cid_C000038098"
      decimals="6"
      id="ixv-89632"
      unitRef="pure">0.0026</oef:OtherExpensesOverAssets>
    <oef:OtherExpensesOverAssets
      contextRef="Pid_S000007069_Cid_C000038101"
      decimals="6"
      id="ixv-89633"
      unitRef="pure">0.0023</oef:OtherExpensesOverAssets>
    <oef:OtherExpensesOverAssets
      contextRef="Pid_S000007069_Cid_C000038100"
      decimals="6"
      id="ixv-89634"
      unitRef="pure">0.0027</oef:OtherExpensesOverAssets>
    <oef:OtherExpensesOverAssets
      contextRef="Pid_S000007069_Cid_C000038102"
      decimals="6"
      id="ixv-89635"
      unitRef="pure">0.0021</oef:OtherExpensesOverAssets>
    <oef:OtherExpensesOverAssets
      contextRef="Pid_S000007069_Cid_C000205069"
      decimals="6"
      id="ixv-89636"
      unitRef="pure">0.0012</oef:OtherExpensesOverAssets>
    <oef:ExpensesOverAssets
      contextRef="Pid_S000007069_Cid_C000038098"
      decimals="6"
      id="ixv-89637"
      unitRef="pure">0.0079</oef:ExpensesOverAssets>
    <oef:ExpensesOverAssets
      contextRef="Pid_S000007069_Cid_C000038101"
      decimals="6"
      id="ixv-89638"
      unitRef="pure">0.0076</oef:ExpensesOverAssets>
    <oef:ExpensesOverAssets
      contextRef="Pid_S000007069_Cid_C000038100"
      decimals="6"
      id="ixv-89639"
      unitRef="pure">0.0155</oef:ExpensesOverAssets>
    <oef:ExpensesOverAssets
      contextRef="Pid_S000007069_Cid_C000038102"
      decimals="6"
      id="ixv-89640"
      unitRef="pure">0.0049</oef:ExpensesOverAssets>
    <oef:ExpensesOverAssets
      contextRef="Pid_S000007069_Cid_C000205069"
      decimals="6"
      id="ixv-89641"
      unitRef="pure">0.0040</oef:ExpensesOverAssets>
    <oef:FeeWaiverOrReimbursementOverAssets
      contextRef="Pid_S000007069_Cid_C000038098"
      decimals="6"
      id="ixv-89642"
      unitRef="pure">-0.0000</oef:FeeWaiverOrReimbursementOverAssets>
    <oef:FeeWaiverOrReimbursementOverAssets
      contextRef="Pid_S000007069_Cid_C000038101"
      decimals="6"
      id="ixv-89643"
      unitRef="pure">-0.0000</oef:FeeWaiverOrReimbursementOverAssets>
    <oef:FeeWaiverOrReimbursementOverAssets
      contextRef="Pid_S000007069_Cid_C000038100"
      decimals="6"
      id="ixv-89644"
      unitRef="pure">-0.0000</oef:FeeWaiverOrReimbursementOverAssets>
    <oef:FeeWaiverOrReimbursementOverAssets
      contextRef="Pid_S000007069_Cid_C000038102"
      decimals="6"
      id="ixv-89645"
      unitRef="pure">-0.0000</oef:FeeWaiverOrReimbursementOverAssets>
    <oef:FeeWaiverOrReimbursementOverAssets
      contextRef="Pid_S000007069_Cid_C000205069"
      decimals="6"
      id="footnoteS000007069AGVT-PROAOE_AC000205069_FW"
      unitRef="pure">-0.0004</oef:FeeWaiverOrReimbursementOverAssets>
    <oef:NetExpensesOverAssets
      contextRef="Pid_S000007069_Cid_C000038098"
      decimals="6"
      id="ixv-89647"
      unitRef="pure">0.0079</oef:NetExpensesOverAssets>
    <oef:NetExpensesOverAssets
      contextRef="Pid_S000007069_Cid_C000038101"
      decimals="6"
      id="ixv-89648"
      unitRef="pure">0.0076</oef:NetExpensesOverAssets>
    <oef:NetExpensesOverAssets
      contextRef="Pid_S000007069_Cid_C000038100"
      decimals="6"
      id="ixv-89649"
      unitRef="pure">0.0155</oef:NetExpensesOverAssets>
    <oef:NetExpensesOverAssets
      contextRef="Pid_S000007069_Cid_C000038102"
      decimals="6"
      id="ixv-89650"
      unitRef="pure">0.0049</oef:NetExpensesOverAssets>
    <oef:NetExpensesOverAssets
      contextRef="Pid_S000007069_Cid_C000205069"
      decimals="6"
      id="ixv-89651"
      unitRef="pure">0.0036</oef:NetExpensesOverAssets>
    <oef:FeeWaiverOrReimbursementOverAssetsDateOfTermination
      contextRef="Pid_S000007069_contentCd_AGVT-PRO"
      id="ixv-15882">2026-12-31</oef:FeeWaiverOrReimbursementOverAssetsDateOfTermination>
    <oef:ExpenseExampleNarrativeTextBlock
      contextRef="Pid_S000007069_contentCd_AGVT-PRO"
      id="ixv-15891">


     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_S000007069_Cid_C000038098"
      decimals="0"
      id="ixv-89652"
      unitRef="usd">477</oef:ExpenseExampleYear01>
    <oef:ExpenseExampleNoRedemptionYear01
      contextRef="Pid_S000007069_Cid_C000038098"
      decimals="0"
      id="ixv-89653"
      unitRef="usd">477</oef:ExpenseExampleNoRedemptionYear01>
    <oef:ExpenseExampleYear01
      contextRef="Pid_S000007069_Cid_C000038101"
      decimals="0"
      id="ixv-89654"
      unitRef="usd">475</oef:ExpenseExampleYear01>
    <oef:ExpenseExampleNoRedemptionYear01
      contextRef="Pid_S000007069_Cid_C000038101"
      decimals="0"
      id="ixv-89655"
      unitRef="usd">475</oef:ExpenseExampleNoRedemptionYear01>
    <oef:ExpenseExampleYear01
      contextRef="Pid_S000007069_Cid_C000038100"
      decimals="0"
      id="ixv-89656"
      unitRef="usd">258</oef:ExpenseExampleYear01>
    <oef:ExpenseExampleNoRedemptionYear01
      contextRef="Pid_S000007069_Cid_C000038100"
      decimals="0"
      id="ixv-89657"
      unitRef="usd">158</oef:ExpenseExampleNoRedemptionYear01>
    <oef:ExpenseExampleYear01
      contextRef="Pid_S000007069_Cid_C000038102"
      decimals="0"
      id="ixv-89658"
      unitRef="usd">50</oef:ExpenseExampleYear01>
    <oef:ExpenseExampleNoRedemptionYear01
      contextRef="Pid_S000007069_Cid_C000038102"
      decimals="0"
      id="ixv-89659"
      unitRef="usd">50</oef:ExpenseExampleNoRedemptionYear01>
    <oef:ExpenseExampleYear01
      contextRef="Pid_S000007069_Cid_C000205069"
      decimals="0"
      id="ixv-89660"
      unitRef="usd">37</oef:ExpenseExampleYear01>
    <oef:ExpenseExampleNoRedemptionYear01
      contextRef="Pid_S000007069_Cid_C000205069"
      decimals="0"
      id="ixv-89661"
      unitRef="usd">37</oef:ExpenseExampleNoRedemptionYear01>
    <oef:ExpenseExampleYear03
      contextRef="Pid_S000007069_Cid_C000038098"
      decimals="0"
      id="ixv-89662"
      unitRef="usd">642</oef:ExpenseExampleYear03>
    <oef:ExpenseExampleNoRedemptionYear03
      contextRef="Pid_S000007069_Cid_C000038098"
      decimals="0"
      id="ixv-89663"
      unitRef="usd">642</oef:ExpenseExampleNoRedemptionYear03>
    <oef:ExpenseExampleYear03
      contextRef="Pid_S000007069_Cid_C000038101"
      decimals="0"
      id="ixv-89664"
      unitRef="usd">633</oef:ExpenseExampleYear03>
    <oef:ExpenseExampleNoRedemptionYear03
      contextRef="Pid_S000007069_Cid_C000038101"
      decimals="0"
      id="ixv-89665"
      unitRef="usd">633</oef:ExpenseExampleNoRedemptionYear03>
    <oef:ExpenseExampleYear03
      contextRef="Pid_S000007069_Cid_C000038100"
      decimals="0"
      id="ixv-89666"
      unitRef="usd">490</oef:ExpenseExampleYear03>
    <oef:ExpenseExampleNoRedemptionYear03
      contextRef="Pid_S000007069_Cid_C000038100"
      decimals="0"
      id="ixv-89667"
      unitRef="usd">490</oef:ExpenseExampleNoRedemptionYear03>
    <oef:ExpenseExampleYear03
      contextRef="Pid_S000007069_Cid_C000038102"
      decimals="0"
      id="ixv-89668"
      unitRef="usd">157</oef:ExpenseExampleYear03>
    <oef:ExpenseExampleNoRedemptionYear03
      contextRef="Pid_S000007069_Cid_C000038102"
      decimals="0"
      id="ixv-89669"
      unitRef="usd">157</oef:ExpenseExampleNoRedemptionYear03>
    <oef:ExpenseExampleYear03
      contextRef="Pid_S000007069_Cid_C000205069"
      decimals="0"
      id="ixv-89670"
      unitRef="usd">123</oef:ExpenseExampleYear03>
    <oef:ExpenseExampleNoRedemptionYear03
      contextRef="Pid_S000007069_Cid_C000205069"
      decimals="0"
      id="ixv-89671"
      unitRef="usd">123</oef:ExpenseExampleNoRedemptionYear03>
    <oef:ExpenseExampleYear05
      contextRef="Pid_S000007069_Cid_C000038098"
      decimals="0"
      id="ixv-89672"
      unitRef="usd">821</oef:ExpenseExampleYear05>
    <oef:ExpenseExampleNoRedemptionYear05
      contextRef="Pid_S000007069_Cid_C000038098"
      decimals="0"
      id="ixv-89673"
      unitRef="usd">821</oef:ExpenseExampleNoRedemptionYear05>
    <oef:ExpenseExampleYear05
      contextRef="Pid_S000007069_Cid_C000038101"
      decimals="0"
      id="ixv-89674"
      unitRef="usd">805</oef:ExpenseExampleYear05>
    <oef:ExpenseExampleNoRedemptionYear05
      contextRef="Pid_S000007069_Cid_C000038101"
      decimals="0"
      id="ixv-89675"
      unitRef="usd">805</oef:ExpenseExampleNoRedemptionYear05>
    <oef:ExpenseExampleYear05
      contextRef="Pid_S000007069_Cid_C000038100"
      decimals="0"
      id="ixv-89676"
      unitRef="usd">845</oef:ExpenseExampleYear05>
    <oef:ExpenseExampleNoRedemptionYear05
      contextRef="Pid_S000007069_Cid_C000038100"
      decimals="0"
      id="ixv-89677"
      unitRef="usd">845</oef:ExpenseExampleNoRedemptionYear05>
    <oef:ExpenseExampleYear05
      contextRef="Pid_S000007069_Cid_C000038102"
      decimals="0"
      id="ixv-89678"
      unitRef="usd">274</oef:ExpenseExampleYear05>
    <oef:ExpenseExampleNoRedemptionYear05
      contextRef="Pid_S000007069_Cid_C000038102"
      decimals="0"
      id="ixv-89679"
      unitRef="usd">274</oef:ExpenseExampleNoRedemptionYear05>
    <oef:ExpenseExampleYear05
      contextRef="Pid_S000007069_Cid_C000205069"
      decimals="0"
      id="ixv-89680"
      unitRef="usd">219</oef:ExpenseExampleYear05>
    <oef:ExpenseExampleNoRedemptionYear05
      contextRef="Pid_S000007069_Cid_C000205069"
      decimals="0"
      id="ixv-89681"
      unitRef="usd">219</oef:ExpenseExampleNoRedemptionYear05>
    <oef:ExpenseExampleYear10
      contextRef="Pid_S000007069_Cid_C000038098"
      decimals="0"
      id="ixv-89682"
      unitRef="usd">1339</oef:ExpenseExampleYear10>
    <oef:ExpenseExampleNoRedemptionYear10
      contextRef="Pid_S000007069_Cid_C000038098"
      decimals="0"
      id="ixv-89683"
      unitRef="usd">1339</oef:ExpenseExampleNoRedemptionYear10>
    <oef:ExpenseExampleYear10
      contextRef="Pid_S000007069_Cid_C000038101"
      decimals="0"
      id="ixv-89684"
      unitRef="usd">1305</oef:ExpenseExampleYear10>
    <oef:ExpenseExampleNoRedemptionYear10
      contextRef="Pid_S000007069_Cid_C000038101"
      decimals="0"
      id="ixv-89685"
      unitRef="usd">1305</oef:ExpenseExampleNoRedemptionYear10>
    <oef:ExpenseExampleYear10
      contextRef="Pid_S000007069_Cid_C000038100"
      decimals="0"
      id="ixv-89686"
      unitRef="usd">1641</oef:ExpenseExampleYear10>
    <oef:ExpenseExampleNoRedemptionYear10
      contextRef="Pid_S000007069_Cid_C000038100"
      decimals="0"
      id="ixv-89687"
      unitRef="usd">1641</oef:ExpenseExampleNoRedemptionYear10>
    <oef:ExpenseExampleYear10
      contextRef="Pid_S000007069_Cid_C000038102"
      decimals="0"
      id="ixv-89688"
      unitRef="usd">616</oef:ExpenseExampleYear10>
    <oef:ExpenseExampleNoRedemptionYear10
      contextRef="Pid_S000007069_Cid_C000038102"
      decimals="0"
      id="ixv-89689"
      unitRef="usd">616</oef:ExpenseExampleNoRedemptionYear10>
    <oef:ExpenseExampleYear10
      contextRef="Pid_S000007069_Cid_C000205069"
      decimals="0"
      id="ixv-89690"
      unitRef="usd">500</oef:ExpenseExampleYear10>
    <oef:ExpenseExampleNoRedemptionYear10
      contextRef="Pid_S000007069_Cid_C000205069"
      decimals="0"
      id="ixv-89691"
      unitRef="usd">500</oef:ExpenseExampleNoRedemptionYear10>
    <oef:PortfolioTurnoverHeading
      contextRef="Pid_S000007069_contentCd_AGVT-PRO"
      id="ixv-16199">


     Portfolio Turnover


   </oef:PortfolioTurnoverHeading>
    <oef:PortfolioTurnoverTextBlock
      contextRef="Pid_S000007069_contentCd_AGVT-PRO"
      id="ixv-16204">


     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



       279


     % of the average value of its portfolio.


   </oef:PortfolioTurnoverTextBlock>
    <oef:PortfolioTurnoverRate
      contextRef="Pid_S000007069_contentCd_AGVT-PRO"
      decimals="4"
      id="ixv-89692"
      unitRef="pure">2.79</oef:PortfolioTurnoverRate>
    <oef:StrategyHeading
      contextRef="Pid_S000007069_contentCd_AGVT-PRO"
      id="ixv-16213">


     Principal Investment Strategies


   </oef:StrategyHeading>
    <oef:StrategyNarrativeTextBlock
      contextRef="Pid_S000007069_contentCd_AGVT-PRO"
      id="ixv-16218">




        Normally investing at least 80% of assets in U.S. Government securities and repurchase agreements for those securities.


       U.S. Government securities are high-quality securities issued or guaranteed by the U.S. Treasury or by an agency or instrumentality of the U.S. Government. U.S. Government securities may be backed by the full faith and credit of the U.S. Treasury, the right to borrow from the U.S. Treasury, or the agency or instrumentality issuing or guaranteeing the security. Certain issuers of U.S. Government securities, including Fannie Mae, Freddie Mac, and the Federal Home Loan Banks, are sponsored or chartered by Congress but their securities are neither issued nor guaranteed by the U.S. Treasury. 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.
     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 75% U.S. Government/25% U.S. Mortgage-Backed Securities Blended Index.
      Allocating assets across different market sectors and maturities.
      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_S000007069_contentCd_AGVT-PRO_RiskMember_InterestRateChangesMember"
      id="ixv-16249">



      Interest Rate Changes.

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

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000007069_contentCd_AGVT-PRO_RiskMember_PrepaymentMember"
      id="ixv-16258">



      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_S000007069_contentCd_AGVT-PRO_RiskMember_IssuerSpecificChangesMember"
      id="ixv-16267">



      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.

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000007069_contentCd_AGVT-PRO_RiskMember_USGovernmentObligationsRiskMember"
      id="ixv-16276">



      U.S. Government Obligations Risk.

     Certain securities in which the fund may invest, including securities issued by certain U.S. Government agencies and U.S. Government sponsored enterprises, are not guaranteed by the U.S. Government or supported by the full faith and credit of the United States.

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000007069_contentCd_AGVT-PRO_RiskMember_LeverageRiskMember"
      id="ixv-16285">



      Leverage Risk.

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

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000007069_contentCd_AGVT-PRO_RiskMember_HighPortfolioTurnoverMember"
      id="ixv-16294">



      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_S000007069_contentCd_AGVT-PRO_RiskMember_RiskNotInsuredDepositoryInstitutionMember"
      id="ixv-16304">


     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_S000007069_contentCd_AGVT-PRO_RiskMember_RiskLoseMoneyMember"
      id="ixv-16312">


     &#160;

     You could lose money by investing in the fund.


   </oef:RiskTextBlock>
    <oef:BarChartAndPerformanceTableHeading
      contextRef="Pid_S000007069_contentCd_AGVT-PRO"
      id="ixv-16321">


     Performance


   </oef:BarChartAndPerformanceTableHeading>
    <oef:PerformanceNarrativeTextBlock
      contextRef="Pid_S000007069_contentCd_AGVT-PRO"
      id="ixv-16326">



       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 additional indexes

      over various periods of time.



     The additional indexes have 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_S000007069_contentCd_AGVT-PRO"
      id="ixv-16332">

      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 additional indexes

      over various periods of time.

     </oef:PerformanceInformationIllustratesVariabilityOfReturns>
    <oef:PerformancePastDoesNotIndicateFuture
      contextRef="Pid_S000007069_contentCd_AGVT-PRO"
      id="ixv-16341">

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

     </oef:PerformancePastDoesNotIndicateFuture>
    <oef:PerformanceAvailabilityWebSiteAddress
      contextRef="Pid_S000007069_contentCd_AGVT-PRO"
      id="ixv-16347">

      institutional.fidelity.com
     </oef:PerformanceAvailabilityWebSiteAddress>
    <oef:BarChartHeading
      contextRef="Pid_S000007069_contentCd_AGVT-PRO"
      id="ixv-16352">


     Year-by-Year Returns

   </oef:BarChartHeading>
    <oef:BarChartNarrativeTextBlock
      contextRef="Pid_S000007069_contentCd_AGVT-PRO"
      id="ixv-16356">




      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_S000007069_contentCd_AGVT-PRO"
      id="ixv-16359">

      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_S000007069_Cid_C000038098_2015"
      decimals="INF"
      id="ixv-89693"
      unitRef="pure">0.0018</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000007069_Cid_C000038098_2016"
      decimals="INF"
      id="ixv-89694"
      unitRef="pure">0.0074</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000007069_Cid_C000038098_2017"
      decimals="INF"
      id="ixv-89695"
      unitRef="pure">0.0178</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000007069_Cid_C000038098_2018"
      decimals="INF"
      id="ixv-89696"
      unitRef="pure">0.0038</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000007069_Cid_C000038098_2019"
      decimals="INF"
      id="ixv-89697"
      unitRef="pure">0.0605</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000007069_Cid_C000038098_2020"
      decimals="INF"
      id="ixv-89698"
      unitRef="pure">0.0645</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000007069_Cid_C000038098_2021"
      decimals="INF"
      id="ixv-89699"
      unitRef="pure">-0.0247</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000007069_Cid_C000038098_2022"
      decimals="INF"
      id="ixv-89700"
      unitRef="pure">-0.1304</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000007069_Cid_C000038098_2023"
      decimals="INF"
      id="ixv-89701"
      unitRef="pure">0.0386</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000007069_Cid_C000038098_2024"
      decimals="INF"
      id="ixv-89702"
      unitRef="pure">0.0029</oef:AnnlRtrPct>
    <oef:HighestQuarterlyReturnLabel
      contextRef="Pid_S000007069_contentCd_AGVT-PRO"
      id="ixv-16471">
          &#160;&#160;&#160;Highest Quarter Return
        </oef:HighestQuarterlyReturnLabel>
    <oef:BarChartHighestQuarterlyReturn
      contextRef="Pid_S000007069_contentCd_AGVT-PRO"
      decimals="4"
      id="ixv-89703"
      unitRef="pure">0.0675</oef:BarChartHighestQuarterlyReturn>
    <oef:BarChartHighestQuarterlyReturnDate
      contextRef="Pid_S000007069_contentCd_AGVT-PRO"
      id="ixv-16481">2020-03-31</oef:BarChartHighestQuarterlyReturnDate>
    <oef:LowestQuarterlyReturnLabel
      contextRef="Pid_S000007069_contentCd_AGVT-PRO"
      id="ixv-16486">
          &#160;&#160;&#160;Lowest Quarter Return
        </oef:LowestQuarterlyReturnLabel>
    <oef:BarChartLowestQuarterlyReturn
      contextRef="Pid_S000007069_contentCd_AGVT-PRO"
      decimals="4"
      id="ixv-89704"
      unitRef="pure">-0.0552</oef:BarChartLowestQuarterlyReturn>
    <oef:BarChartLowestQuarterlyReturnDate
      contextRef="Pid_S000007069_contentCd_AGVT-PRO"
      id="ixv-16497">2022-03-31</oef:BarChartLowestQuarterlyReturnDate>
    <oef:YearToDateReturnLabel
      contextRef="Pid_S000007069_contentCd_AGVT-PRO"
      id="ixv-16502">
          &#160;&#160;&#160;Year-to-Date Return
        </oef:YearToDateReturnLabel>
    <oef:BarChartYearToDateReturn
      contextRef="Pid_S000007069_contentCd_AGVT-PRO"
      decimals="4"
      id="ixv-89705"
      unitRef="pure">0.0533</oef:BarChartYearToDateReturn>
    <oef:BarChartYearToDateReturnDate
      contextRef="Pid_S000007069_contentCd_AGVT-PRO"
      id="ixv-16512">2025-09-30</oef:BarChartYearToDateReturnDate>
    <oef:PerformanceTableHeading
      contextRef="Pid_S000007069_contentCd_AGVT-PRO"
      id="ixv-16517">


     Average Annual Returns


   </oef:PerformanceTableHeading>
    <oef:PerformanceTableNarrativeTextBlock
      contextRef="Pid_S000007069_contentCd_AGVT-PRO"
      id="ixv-16523">




      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_S000007069_contentCd_AGVT-PRO"
      id="ixv-16526">

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

     </oef:PerformanceTableDoesReflectSalesLoads>
    <oef:PerformanceTableUsesHighestFederalRate
      contextRef="Pid_S000007069_contentCd_AGVT-PRO"
      id="ixv-16531">

      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_S000007069_contentCd_AGVT-PRO"
      id="ixv-16536">

      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_S000007069_contentCd_AGVT-PRO"
      id="ixv-16542">

      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_S000007069_contentCd_AGVT-PRO"
      id="ixv-16546">

      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_S000007069_Cid_C000038098_ReturnBeforeTaxes_01"
      id="ixv-16577">
         Return Before Taxes
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007069_Cid_C000038098_ReturnBeforeTaxes_01"
      decimals="4"
      id="ixv-89706"
      unitRef="pure">-0.0372</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007069_Cid_C000038098_ReturnBeforeTaxes_05"
      decimals="4"
      id="ixv-89707"
      unitRef="pure">-0.0202</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007069_Cid_C000038098_ReturnBeforeTaxes_10"
      decimals="4"
      id="ixv-89708"
      unitRef="pure">-0.0013</oef:AvgAnnlRtrPct>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000007069_Cid_C000038098_AfterTaxesOnDistributions_01"
      id="ixv-16597">
         Return After Taxes on Distributions
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007069_Cid_C000038098_AfterTaxesOnDistributions_01"
      decimals="4"
      id="ixv-89709"
      unitRef="pure">-0.0490</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007069_Cid_C000038098_AfterTaxesOnDistributions_05"
      decimals="4"
      id="ixv-89710"
      unitRef="pure">-0.0274</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007069_Cid_C000038098_AfterTaxesOnDistributions_10"
      decimals="4"
      id="ixv-89711"
      unitRef="pure">-0.0086</oef:AvgAnnlRtrPct>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000007069_Cid_C000038098_AfterTaxesOnDistributionsAndSales_01"
      id="ixv-16616">
          Return After Taxes on Distributions and Sale of Fund Shares
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007069_Cid_C000038098_AfterTaxesOnDistributionsAndSales_01"
      decimals="4"
      id="ixv-89712"
      unitRef="pure">-0.0208</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007069_Cid_C000038098_AfterTaxesOnDistributionsAndSales_05"
      decimals="4"
      id="ixv-89713"
      unitRef="pure">-0.0179</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007069_Cid_C000038098_AfterTaxesOnDistributionsAndSales_10"
      decimals="4"
      id="ixv-89714"
      unitRef="pure">-0.0038</oef:AvgAnnlRtrPct>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000007069_Cid_C000038101_ReturnBeforeTaxes_01"
      id="ixv-16634">
         Return Before Taxes
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007069_Cid_C000038101_ReturnBeforeTaxes_01"
      decimals="4"
      id="ixv-89715"
      unitRef="pure">-0.0369</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007069_Cid_C000038101_ReturnBeforeTaxes_05"
      decimals="4"
      id="ixv-89716"
      unitRef="pure">-0.0199</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007069_Cid_C000038101_ReturnBeforeTaxes_10"
      decimals="4"
      id="ixv-89717"
      unitRef="pure">-0.0011</oef:AvgAnnlRtrPct>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000007069_Cid_C000038100_ReturnBeforeTaxes_01"
      id="ixv-16652">
         Return Before Taxes
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007069_Cid_C000038100_ReturnBeforeTaxes_01"
      decimals="4"
      id="ixv-89718"
      unitRef="pure">-0.0144</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007069_Cid_C000038100_ReturnBeforeTaxes_05"
      decimals="4"
      id="ixv-89719"
      unitRef="pure">-0.0196</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007069_Cid_C000038100_ReturnBeforeTaxes_10"
      decimals="4"
      id="ixv-89720"
      unitRef="pure">-0.0032</oef:AvgAnnlRtrPct>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000007069_Cid_C000038102_ReturnBeforeTaxes_01"
      id="ixv-16670">
         Return Before Taxes
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007069_Cid_C000038102_ReturnBeforeTaxes_01"
      decimals="4"
      id="ixv-89721"
      unitRef="pure">0.0058</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007069_Cid_C000038102_ReturnBeforeTaxes_05"
      decimals="4"
      id="ixv-89722"
      unitRef="pure">-0.0093</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007069_Cid_C000038102_ReturnBeforeTaxes_10"
      decimals="4"
      id="ixv-89723"
      unitRef="pure">0.0057</oef:AvgAnnlRtrPct>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000007069_Cid_C000205069_ReturnBeforeTaxes_01"
      id="ixv-16686">
         Return Before Taxes
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007069_Cid_C000205069_ReturnBeforeTaxes_01"
      decimals="4"
      id="ixv-89724"
      unitRef="pure">0.0073</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007069_Cid_C000205069_ReturnBeforeTaxes_05"
      decimals="4"
      id="ixv-89725"
      unitRef="pure">-0.0081</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007069_Cid_C000205069_ReturnBeforeTaxes_AverageAnnualReturnSinceInception"
      decimals="4"
      id="footnoteAGVT-PROS000007069AAR_A_RBT_loc"
      unitRef="pure">0.0072</oef:AvgAnnlRtrPct>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000007069_Indexid_F0682_contentCd_AGVT-PRO_01"
      id="ixv-16702">
         Bloomberg 75% U.S. Government/25% U.S. Mortgage-Backed Securities Blended Index
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007069_Indexid_F0682_contentCd_AGVT-PRO_01"
      decimals="4"
      id="ixv-89727"
      unitRef="pure">0.0077</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007069_Indexid_F0682_contentCd_AGVT-PRO_05"
      decimals="4"
      id="ixv-89728"
      unitRef="pure">-0.0065</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007069_Indexid_F0682_contentCd_AGVT-PRO_10"
      decimals="4"
      id="ixv-89729"
      unitRef="pure">0.0087</oef:AvgAnnlRtrPct>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000007069_Indexid_LB003_contentCd_AGVT-PRO_01"
      id="ixv-16728">
         Bloomberg U.S. Government Bond Index
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007069_Indexid_LB003_contentCd_AGVT-PRO_01"
      decimals="4"
      id="ixv-89730"
      unitRef="pure">0.0062</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007069_Indexid_LB003_contentCd_AGVT-PRO_05"
      decimals="4"
      id="ixv-89731"
      unitRef="pure">-0.0063</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007069_Indexid_LB003_contentCd_AGVT-PRO_10"
      decimals="4"
      id="ixv-89732"
      unitRef="pure">0.0085</oef:AvgAnnlRtrPct>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000007069_Indexid_LB001_contentCd_AGVT-PRO_01"
      id="ixv-16754">
         Bloomberg U.S. Aggregate Bond Index
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007069_Indexid_LB001_contentCd_AGVT-PRO_01"
      decimals="4"
      id="ixv-89733"
      unitRef="pure">0.0125</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007069_Indexid_LB001_contentCd_AGVT-PRO_05"
      decimals="4"
      id="ixv-89734"
      unitRef="pure">-0.0033</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007069_Indexid_LB001_contentCd_AGVT-PRO_10"
      decimals="4"
      id="ixv-89735"
      unitRef="pure">0.0135</oef:AvgAnnlRtrPct>
    <oef:AnnualReturnInceptionDate contextRef="Pid_S000007069_Cid_C000205069" id="ixv-16796">2018-10-02</oef:AnnualReturnInceptionDate>
    <oef:RiskReturnHeading
      contextRef="Pid_S000007069_contentCd_GOV-SLM-PRO"
      id="ixv-23345">


     Fund Summary

     Fund /Class:
     Fidelity&#xae; Government Income Fund
     /Fidelity&#xae; Government Income Fund

   </oef:RiskReturnHeading>
    <oef:ObjectiveHeading
      contextRef="Pid_S000007069_contentCd_GOV-SLM-PRO"
      id="ixv-23358">


     Investment Objective


   </oef:ObjectiveHeading>
    <oef:ObjectivePrimaryTextBlock
      contextRef="Pid_S000007069_contentCd_GOV-SLM-PRO"
      id="ixv-23363">


     Fidelity&#xae; Government Income Fund seeks a high level of current income, consistent with preservation of principal.


   </oef:ObjectivePrimaryTextBlock>
    <oef:ExpenseHeading
      contextRef="Pid_S000007069_contentCd_GOV-SLM-PRO"
      id="ixv-23368">


     Fee Table


   </oef:ExpenseHeading>
    <oef:ExpenseNarrativeTextBlock
      contextRef="Pid_S000007069_contentCd_GOV-SLM-PRO"
      id="ixv-23374">


     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_S000007069_contentCd_GOV-SLM-PRO"
      id="ixv-23385">


     Shareholder fees


   </oef:ShareholderFeesCaption>
    <oef:ShareholderFeeOther
      contextRef="Pid_S000007069_contentCd_GOV-SLM-PRO"
      decimals="0"
      id="ixv-89736"
      unitRef="usd">0</oef:ShareholderFeeOther>
    <oef:OperatingExpensesCaption
      contextRef="Pid_S000007069_contentCd_GOV-SLM-PRO"
      id="ixv-23400">


     Annual Operating Expenses


   </oef:OperatingExpensesCaption>
    <oef:ManagementFeesOverAssets
      contextRef="Pid_S000007069_Cid_C000019283"
      decimals="6"
      id="ixv-89737"
      unitRef="pure">0.0028</oef:ManagementFeesOverAssets>
    <oef:DistributionAndService12b1FeesOverAssets
      contextRef="Pid_S000007069_Cid_C000019283"
      decimals="6"
      id="ixv-89738"
      unitRef="pure">0</oef:DistributionAndService12b1FeesOverAssets>
    <oef:OtherExpensesOverAssets
      contextRef="Pid_S000007069_Cid_C000019283"
      decimals="6"
      id="ixv-89739"
      unitRef="pure">0.0017</oef:OtherExpensesOverAssets>
    <oef:ExpensesOverAssets
      contextRef="Pid_S000007069_Cid_C000019283"
      decimals="6"
      id="ixv-89740"
      unitRef="pure">0.0045</oef:ExpensesOverAssets>
    <oef:ExpenseExampleNarrativeTextBlock
      contextRef="Pid_S000007069_contentCd_GOV-SLM-PRO"
      id="ixv-23447">




     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_S000007069_Cid_C000019283"
      decimals="0"
      id="ixv-89741"
      unitRef="usd">46</oef:ExpenseExampleYear01>
    <oef:ExpenseExampleYear03
      contextRef="Pid_S000007069_Cid_C000019283"
      decimals="0"
      id="ixv-89742"
      unitRef="usd">144</oef:ExpenseExampleYear03>
    <oef:ExpenseExampleYear05
      contextRef="Pid_S000007069_Cid_C000019283"
      decimals="0"
      id="ixv-89743"
      unitRef="usd">252</oef:ExpenseExampleYear05>
    <oef:ExpenseExampleYear10
      contextRef="Pid_S000007069_Cid_C000019283"
      decimals="0"
      id="ixv-89744"
      unitRef="usd">567</oef:ExpenseExampleYear10>
    <oef:PortfolioTurnoverHeading
      contextRef="Pid_S000007069_contentCd_GOV-SLM-PRO"
      id="ixv-23505">


     Portfolio Turnover


   </oef:PortfolioTurnoverHeading>
    <oef:PortfolioTurnoverTextBlock
      contextRef="Pid_S000007069_contentCd_GOV-SLM-PRO"
      id="ixv-23510">


     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



       279


     % of the average value of its portfolio.


   </oef:PortfolioTurnoverTextBlock>
    <oef:PortfolioTurnoverRate
      contextRef="Pid_S000007069_contentCd_GOV-SLM-PRO"
      decimals="4"
      id="ixv-89745"
      unitRef="pure">2.79</oef:PortfolioTurnoverRate>
    <oef:StrategyHeading
      contextRef="Pid_S000007069_contentCd_GOV-SLM-PRO"
      id="ixv-23519">


     Principal Investment Strategies


   </oef:StrategyHeading>
    <oef:StrategyNarrativeTextBlock
      contextRef="Pid_S000007069_contentCd_GOV-SLM-PRO"
      id="ixv-23524">




        Normally investing at least 80% of assets in U.S. Government securities and repurchase agreements for those securities.


       U.S. Government securities are high-quality securities issued or guaranteed by the U.S. Treasury or by an agency or instrumentality of the U.S. Government. U.S. Government securities may be backed by the full faith and credit of the U.S. Treasury, the right to borrow from the U.S. Treasury, or the agency or instrumentality issuing or guaranteeing the security. Certain issuers of U.S. Government securities, including Fannie Mae, Freddie Mac, and the Federal Home Loan Banks, are sponsored or chartered by Congress but their securities are neither issued nor guaranteed by the U.S. Treasury. 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.
     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 75% U.S. Government/25% U.S. Mortgage-Backed Securities Blended Index.
      Allocating assets across different market sectors and maturities.
      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_S000007069_contentCd_GOV-SLM-PRO_RiskMember_InterestRateChangesMember"
      id="ixv-23555">



      Interest Rate Changes.

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

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000007069_contentCd_GOV-SLM-PRO_RiskMember_PrepaymentMember"
      id="ixv-23564">



      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_S000007069_contentCd_GOV-SLM-PRO_RiskMember_IssuerSpecificChangesMember"
      id="ixv-23573">



      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.

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000007069_contentCd_GOV-SLM-PRO_RiskMember_USGovernmentObligationsRiskMember"
      id="ixv-23582">



      U.S. Government Obligations Risk.

     Certain securities in which the fund may invest, including securities issued by certain U.S. Government agencies and U.S. Government sponsored enterprises, are not guaranteed by the U.S. Government or supported by the full faith and credit of the United States.

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000007069_contentCd_GOV-SLM-PRO_RiskMember_LeverageRiskMember"
      id="ixv-23591">



      Leverage Risk.

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

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000007069_contentCd_GOV-SLM-PRO_RiskMember_HighPortfolioTurnoverMember"
      id="ixv-23600">



      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_S000007069_contentCd_GOV-SLM-PRO_RiskMember_RiskNotInsuredDepositoryInstitutionMember"
      id="ixv-23610">


     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_S000007069_contentCd_GOV-SLM-PRO_RiskMember_RiskLoseMoneyMember"
      id="ixv-23618">


     &#160;

     You could lose money by investing in the fund.


   </oef:RiskTextBlock>
    <oef:BarChartAndPerformanceTableHeading
      contextRef="Pid_S000007069_contentCd_GOV-SLM-PRO"
      id="ixv-23627">


     Performance


   </oef:BarChartAndPerformanceTableHeading>
    <oef:PerformanceNarrativeTextBlock
      contextRef="Pid_S000007069_contentCd_GOV-SLM-PRO"
      id="ixv-23632">



       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 additional indexes

      over various periods of time.



     The additional indexes have 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_S000007069_contentCd_GOV-SLM-PRO"
      id="ixv-23638">

      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 additional indexes

      over various periods of time.

     </oef:PerformanceInformationIllustratesVariabilityOfReturns>
    <oef:PerformancePastDoesNotIndicateFuture
      contextRef="Pid_S000007069_contentCd_GOV-SLM-PRO"
      id="ixv-23647">

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

     </oef:PerformancePastDoesNotIndicateFuture>
    <oef:PerformanceAvailabilityWebSiteAddress
      contextRef="Pid_S000007069_contentCd_GOV-SLM-PRO"
      id="ixv-23653">

      www.fidelity.com
     </oef:PerformanceAvailabilityWebSiteAddress>
    <oef:BarChartHeading
      contextRef="Pid_S000007069_contentCd_GOV-SLM-PRO"
      id="ixv-23658">


     Year-by-Year Returns

   </oef:BarChartHeading>
    <oef:AnnlRtrPct
      contextRef="Pid_S000007069_Cid_C000019283_2015"
      decimals="INF"
      id="ixv-89746"
      unitRef="pure">0.0050</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000007069_Cid_C000019283_2016"
      decimals="INF"
      id="ixv-89747"
      unitRef="pure">0.0105</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000007069_Cid_C000019283_2017"
      decimals="INF"
      id="ixv-89748"
      unitRef="pure">0.0221</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000007069_Cid_C000019283_2018"
      decimals="INF"
      id="ixv-89749"
      unitRef="pure">0.0061</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000007069_Cid_C000019283_2019"
      decimals="INF"
      id="ixv-89750"
      unitRef="pure">0.0641</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000007069_Cid_C000019283_2020"
      decimals="INF"
      id="ixv-89751"
      unitRef="pure">0.0679</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000007069_Cid_C000019283_2021"
      decimals="INF"
      id="ixv-89752"
      unitRef="pure">-0.0210</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000007069_Cid_C000019283_2022"
      decimals="INF"
      id="ixv-89753"
      unitRef="pure">-0.1277</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000007069_Cid_C000019283_2023"
      decimals="INF"
      id="ixv-89754"
      unitRef="pure">0.0421</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000007069_Cid_C000019283_2024"
      decimals="INF"
      id="ixv-89755"
      unitRef="pure">0.0063</oef:AnnlRtrPct>
    <oef:HighestQuarterlyReturnLabel
      contextRef="Pid_S000007069_contentCd_GOV-SLM-PRO"
      id="ixv-23769">
          &#160;&#160;&#160;Highest Quarter Return
        </oef:HighestQuarterlyReturnLabel>
    <oef:BarChartHighestQuarterlyReturn
      contextRef="Pid_S000007069_contentCd_GOV-SLM-PRO"
      decimals="4"
      id="ixv-89756"
      unitRef="pure">0.0685</oef:BarChartHighestQuarterlyReturn>
    <oef:BarChartHighestQuarterlyReturnDate
      contextRef="Pid_S000007069_contentCd_GOV-SLM-PRO"
      id="ixv-23779">2020-03-31</oef:BarChartHighestQuarterlyReturnDate>
    <oef:LowestQuarterlyReturnLabel
      contextRef="Pid_S000007069_contentCd_GOV-SLM-PRO"
      id="ixv-23784">
          &#160;&#160;&#160;Lowest Quarter Return
        </oef:LowestQuarterlyReturnLabel>
    <oef:BarChartLowestQuarterlyReturn
      contextRef="Pid_S000007069_contentCd_GOV-SLM-PRO"
      decimals="4"
      id="ixv-89757"
      unitRef="pure">-0.0544</oef:BarChartLowestQuarterlyReturn>
    <oef:BarChartLowestQuarterlyReturnDate
      contextRef="Pid_S000007069_contentCd_GOV-SLM-PRO"
      id="ixv-23795">2022-03-31</oef:BarChartLowestQuarterlyReturnDate>
    <oef:YearToDateReturnLabel
      contextRef="Pid_S000007069_contentCd_GOV-SLM-PRO"
      id="ixv-23800">
          &#160;&#160;&#160;Year-to-Date Return
        </oef:YearToDateReturnLabel>
    <oef:BarChartYearToDateReturn
      contextRef="Pid_S000007069_contentCd_GOV-SLM-PRO"
      decimals="4"
      id="ixv-89758"
      unitRef="pure">0.0560</oef:BarChartYearToDateReturn>
    <oef:BarChartYearToDateReturnDate
      contextRef="Pid_S000007069_contentCd_GOV-SLM-PRO"
      id="ixv-23810">2025-09-30</oef:BarChartYearToDateReturnDate>
    <oef:PerformanceTableHeading
      contextRef="Pid_S000007069_contentCd_GOV-SLM-PRO"
      id="ixv-23815">


     Average Annual Returns


   </oef:PerformanceTableHeading>
    <oef:PerformanceTableNarrativeTextBlock
      contextRef="Pid_S000007069_contentCd_GOV-SLM-PRO"
      id="ixv-23820">




      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_S000007069_contentCd_GOV-SLM-PRO"
      id="ixv-23823">

      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_S000007069_contentCd_GOV-SLM-PRO"
      id="ixv-23830">

      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_S000007069_contentCd_GOV-SLM-PRO"
      id="ixv-23835">

      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_S000007069_Cid_C000019283_ReturnBeforeTaxes_01"
      id="ixv-23880">
         Return Before Taxes
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007069_Cid_C000019283_ReturnBeforeTaxes_01"
      decimals="4"
      id="ixv-89759"
      unitRef="pure">0.0063</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007069_Cid_C000019283_ReturnBeforeTaxes_05"
      decimals="4"
      id="ixv-89760"
      unitRef="pure">-0.0089</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007069_Cid_C000019283_ReturnBeforeTaxes_10"
      decimals="4"
      id="ixv-89761"
      unitRef="pure">0.0061</oef:AvgAnnlRtrPct>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000007069_Cid_C000019283_AfterTaxesOnDistributions_01"
      id="ixv-23896">
         Return After Taxes on Distributions
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007069_Cid_C000019283_AfterTaxesOnDistributions_01"
      decimals="4"
      id="ixv-89762"
      unitRef="pure">-0.0075</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007069_Cid_C000019283_AfterTaxesOnDistributions_05"
      decimals="4"
      id="ixv-89763"
      unitRef="pure">-0.0174</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007069_Cid_C000019283_AfterTaxesOnDistributions_10"
      decimals="4"
      id="ixv-89764"
      unitRef="pure">-0.0026</oef:AvgAnnlRtrPct>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000007069_Cid_C000019283_AfterTaxesOnDistributionsAndSales_01"
      id="ixv-23914">
         Return After Taxes on Distributions and Sale of Fund Shares
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007069_Cid_C000019283_AfterTaxesOnDistributionsAndSales_01"
      decimals="4"
      id="ixv-89765"
      unitRef="pure">0.0050</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007069_Cid_C000019283_AfterTaxesOnDistributionsAndSales_05"
      decimals="4"
      id="ixv-89766"
      unitRef="pure">-0.0100</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007069_Cid_C000019283_AfterTaxesOnDistributionsAndSales_10"
      decimals="4"
      id="ixv-89767"
      unitRef="pure">0.0012</oef:AvgAnnlRtrPct>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000007069_Indexid_F0682_contentCd_GOV-SLM-PRO_01"
      id="ixv-23931">
         Bloomberg 75% U.S. Government/25% U.S. Mortgage-Backed Securities Blended Index
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007069_Indexid_F0682_contentCd_GOV-SLM-PRO_01"
      decimals="4"
      id="ixv-89768"
      unitRef="pure">0.0077</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007069_Indexid_F0682_contentCd_GOV-SLM-PRO_05"
      decimals="4"
      id="ixv-89769"
      unitRef="pure">-0.0065</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007069_Indexid_F0682_contentCd_GOV-SLM-PRO_10"
      decimals="4"
      id="ixv-89770"
      unitRef="pure">0.0087</oef:AvgAnnlRtrPct>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000007069_Indexid_LB003_contentCd_GOV-SLM-PRO_01"
      id="ixv-23957">
         Bloomberg U.S. Government Bond Index
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007069_Indexid_LB003_contentCd_GOV-SLM-PRO_01"
      decimals="4"
      id="ixv-89771"
      unitRef="pure">0.0062</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007069_Indexid_LB003_contentCd_GOV-SLM-PRO_05"
      decimals="4"
      id="ixv-89772"
      unitRef="pure">-0.0063</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007069_Indexid_LB003_contentCd_GOV-SLM-PRO_10"
      decimals="4"
      id="ixv-89773"
      unitRef="pure">0.0085</oef:AvgAnnlRtrPct>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000007069_Indexid_LB001_contentCd_GOV-SLM-PRO_01"
      id="ixv-23983">
         Bloomberg U.S. Aggregate Bond Index
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007069_Indexid_LB001_contentCd_GOV-SLM-PRO_01"
      decimals="4"
      id="ixv-89774"
      unitRef="pure">0.0125</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007069_Indexid_LB001_contentCd_GOV-SLM-PRO_05"
      decimals="4"
      id="ixv-89775"
      unitRef="pure">-0.0033</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007069_Indexid_LB001_contentCd_GOV-SLM-PRO_10"
      decimals="4"
      id="ixv-89776"
      unitRef="pure">0.0135</oef:AvgAnnlRtrPct>
    <oef:RiskReturnHeading
      contextRef="Pid_S000007070_contentCd_GOV-SLM-PRO"
      id="ixv-24101">


     Fund Summary

     Fund:
     Fidelity&#xae; Intermediate Government Income Fund

   </oef:RiskReturnHeading>
    <oef:ObjectiveHeading
      contextRef="Pid_S000007070_contentCd_GOV-SLM-PRO"
      id="ixv-24110">


     Investment Objective


   </oef:ObjectiveHeading>
    <oef:ObjectivePrimaryTextBlock
      contextRef="Pid_S000007070_contentCd_GOV-SLM-PRO"
      id="ixv-24115">


     Fidelity&#xae; Intermediate Government Income Fund seeks a high level of current income as is consistent with preservation of capital.


   </oef:ObjectivePrimaryTextBlock>
    <oef:ExpenseHeading
      contextRef="Pid_S000007070_contentCd_GOV-SLM-PRO"
      id="ixv-24120">


     Fee Table


   </oef:ExpenseHeading>
    <oef:ExpenseNarrativeTextBlock
      contextRef="Pid_S000007070_contentCd_GOV-SLM-PRO"
      id="ixv-24126">


     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_S000007070_contentCd_GOV-SLM-PRO"
      id="ixv-24137">


     Shareholder fees


   </oef:ShareholderFeesCaption>
    <oef:ShareholderFeeOther
      contextRef="Pid_S000007070_contentCd_GOV-SLM-PRO"
      decimals="0"
      id="ixv-89777"
      unitRef="usd">0</oef:ShareholderFeeOther>
    <oef:OperatingExpensesCaption
      contextRef="Pid_S000007070_contentCd_GOV-SLM-PRO"
      id="ixv-24152">


     Annual Operating Expenses


   </oef:OperatingExpensesCaption>
    <oef:ManagementFeesOverAssets
      contextRef="Pid_S000007070_Cid_C000019284"
      decimals="6"
      id="ixv-89778"
      unitRef="pure">0.0028</oef:ManagementFeesOverAssets>
    <oef:DistributionAndService12b1FeesOverAssets
      contextRef="Pid_S000007070_Cid_C000019284"
      decimals="6"
      id="ixv-89779"
      unitRef="pure">0</oef:DistributionAndService12b1FeesOverAssets>
    <oef:OtherExpensesOverAssets
      contextRef="Pid_S000007070_Cid_C000019284"
      decimals="6"
      id="ixv-89780"
      unitRef="pure">0.0017</oef:OtherExpensesOverAssets>
    <oef:ExpensesOverAssets
      contextRef="Pid_S000007070_Cid_C000019284"
      decimals="6"
      id="ixv-89781"
      unitRef="pure">0.0045</oef:ExpensesOverAssets>
    <oef:ExpenseExampleNarrativeTextBlock
      contextRef="Pid_S000007070_contentCd_GOV-SLM-PRO"
      id="ixv-24199">




     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_S000007070_Cid_C000019284"
      decimals="0"
      id="ixv-89782"
      unitRef="usd">46</oef:ExpenseExampleYear01>
    <oef:ExpenseExampleYear03
      contextRef="Pid_S000007070_Cid_C000019284"
      decimals="0"
      id="ixv-89783"
      unitRef="usd">144</oef:ExpenseExampleYear03>
    <oef:ExpenseExampleYear05
      contextRef="Pid_S000007070_Cid_C000019284"
      decimals="0"
      id="ixv-89784"
      unitRef="usd">252</oef:ExpenseExampleYear05>
    <oef:ExpenseExampleYear10
      contextRef="Pid_S000007070_Cid_C000019284"
      decimals="0"
      id="ixv-89785"
      unitRef="usd">567</oef:ExpenseExampleYear10>
    <oef:PortfolioTurnoverHeading
      contextRef="Pid_S000007070_contentCd_GOV-SLM-PRO"
      id="ixv-24257">


     Portfolio Turnover


   </oef:PortfolioTurnoverHeading>
    <oef:PortfolioTurnoverTextBlock
      contextRef="Pid_S000007070_contentCd_GOV-SLM-PRO"
      id="ixv-24262">


     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



       135


     % of the average value of its portfolio.


   </oef:PortfolioTurnoverTextBlock>
    <oef:PortfolioTurnoverRate
      contextRef="Pid_S000007070_contentCd_GOV-SLM-PRO"
      decimals="4"
      id="ixv-89786"
      unitRef="pure">1.35</oef:PortfolioTurnoverRate>
    <oef:StrategyHeading
      contextRef="Pid_S000007070_contentCd_GOV-SLM-PRO"
      id="ixv-24271">


     Principal Investment Strategies


   </oef:StrategyHeading>
    <oef:StrategyNarrativeTextBlock
      contextRef="Pid_S000007070_contentCd_GOV-SLM-PRO"
      id="ixv-24276">




        Normally investing at least 80% of assets in U.S. Government securities and repurchase agreements for those securities.


       U.S. Government securities are high-quality securities issued or guaranteed by the U.S. Treasury or by an agency or instrumentality of the U.S. Government. U.S. Government securities may be backed by the full faith and credit of the U.S. Treasury, the right to borrow from the U.S. Treasury, or the agency or instrumentality issuing or guaranteeing the security. Certain issuers of U.S. Government securities, including Fannie Mae, Freddie Mac, and the Federal Home Loan Banks, are sponsored or chartered by Congress but their securities are neither issued nor guaranteed by the U.S. Treasury. 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.
     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 Bond Index.
      Normally maintaining a dollar-weighted average maturity between three and 10 years.
      Allocating assets across different market sectors and maturities.
      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_S000007070_contentCd_GOV-SLM-PRO_RiskMember_InterestRateChangesMember"
      id="ixv-24309">



      Interest Rate Changes.

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

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000007070_contentCd_GOV-SLM-PRO_RiskMember_PrepaymentMember"
      id="ixv-24318">



      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_S000007070_contentCd_GOV-SLM-PRO_RiskMember_IssuerSpecificChangesMember"
      id="ixv-24327">



      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.

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000007070_contentCd_GOV-SLM-PRO_RiskMember_USGovernmentObligationsRiskMember"
      id="ixv-24336">



      U.S. Government Obligations Risk.

     Certain securities in which the fund may invest, including securities issued by certain U.S. Government agencies and U.S. Government sponsored enterprises, are not guaranteed by the U.S. Government or supported by the full faith and credit of the United States.

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000007070_contentCd_GOV-SLM-PRO_RiskMember_LeverageRiskMember"
      id="ixv-24345">



      Leverage Risk.

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

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000007070_contentCd_GOV-SLM-PRO_RiskMember_HighPortfolioTurnoverMember"
      id="ixv-24354">



      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_S000007070_contentCd_GOV-SLM-PRO_RiskMember_RiskNotInsuredDepositoryInstitutionMember"
      id="ixv-24364">


     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_S000007070_contentCd_GOV-SLM-PRO_RiskMember_RiskLoseMoneyMember"
      id="ixv-24372">


     &#160;

     You could lose money by investing in the fund.


   </oef:RiskTextBlock>
    <oef:BarChartAndPerformanceTableHeading
      contextRef="Pid_S000007070_contentCd_GOV-SLM-PRO"
      id="ixv-24381">


     Performance


   </oef:BarChartAndPerformanceTableHeading>
    <oef:PerformanceNarrativeTextBlock
      contextRef="Pid_S000007070_contentCd_GOV-SLM-PRO"
      id="ixv-24386">



       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_S000007070_contentCd_GOV-SLM-PRO"
      id="ixv-24392">

      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_S000007070_contentCd_GOV-SLM-PRO"
      id="ixv-24401">

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

     </oef:PerformancePastDoesNotIndicateFuture>
    <oef:PerformanceAvailabilityWebSiteAddress
      contextRef="Pid_S000007070_contentCd_GOV-SLM-PRO"
      id="ixv-24407">

      www.fidelity.com
     </oef:PerformanceAvailabilityWebSiteAddress>
    <oef:BarChartHeading
      contextRef="Pid_S000007070_contentCd_GOV-SLM-PRO"
      id="ixv-24412">


     Year-by-Year Returns

   </oef:BarChartHeading>
    <oef:AnnlRtrPct
      contextRef="Pid_S000007070_Cid_C000019284_2015"
      decimals="INF"
      id="ixv-89787"
      unitRef="pure">0.0081</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000007070_Cid_C000019284_2016"
      decimals="INF"
      id="ixv-89788"
      unitRef="pure">0.0088</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000007070_Cid_C000019284_2017"
      decimals="INF"
      id="ixv-89789"
      unitRef="pure">0.0098</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000007070_Cid_C000019284_2018"
      decimals="INF"
      id="ixv-89790"
      unitRef="pure">0.0118</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000007070_Cid_C000019284_2019"
      decimals="INF"
      id="ixv-89791"
      unitRef="pure">0.0483</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000007070_Cid_C000019284_2020"
      decimals="INF"
      id="ixv-89792"
      unitRef="pure">0.0545</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000007070_Cid_C000019284_2021"
      decimals="INF"
      id="ixv-89793"
      unitRef="pure">-0.0214</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000007070_Cid_C000019284_2022"
      decimals="INF"
      id="ixv-89794"
      unitRef="pure">-0.0845</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000007070_Cid_C000019284_2023"
      decimals="INF"
      id="ixv-89795"
      unitRef="pure">0.0386</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000007070_Cid_C000019284_2024"
      decimals="INF"
      id="ixv-89796"
      unitRef="pure">0.0224</oef:AnnlRtrPct>
    <oef:HighestQuarterlyReturnLabel
      contextRef="Pid_S000007070_contentCd_GOV-SLM-PRO"
      id="ixv-24523">
          &#160;&#160;&#160;Highest Quarter Return
        </oef:HighestQuarterlyReturnLabel>
    <oef:BarChartHighestQuarterlyReturn
      contextRef="Pid_S000007070_contentCd_GOV-SLM-PRO"
      decimals="4"
      id="ixv-89797"
      unitRef="pure">0.0524</oef:BarChartHighestQuarterlyReturn>
    <oef:BarChartHighestQuarterlyReturnDate
      contextRef="Pid_S000007070_contentCd_GOV-SLM-PRO"
      id="ixv-24533">2020-03-31</oef:BarChartHighestQuarterlyReturnDate>
    <oef:LowestQuarterlyReturnLabel
      contextRef="Pid_S000007070_contentCd_GOV-SLM-PRO"
      id="ixv-24538">
          &#160;&#160;&#160;Lowest Quarter Return
        </oef:LowestQuarterlyReturnLabel>
    <oef:BarChartLowestQuarterlyReturn
      contextRef="Pid_S000007070_contentCd_GOV-SLM-PRO"
      decimals="4"
      id="ixv-89798"
      unitRef="pure">-0.0439</oef:BarChartLowestQuarterlyReturn>
    <oef:BarChartLowestQuarterlyReturnDate
      contextRef="Pid_S000007070_contentCd_GOV-SLM-PRO"
      id="ixv-24549">2022-03-31</oef:BarChartLowestQuarterlyReturnDate>
    <oef:YearToDateReturnLabel
      contextRef="Pid_S000007070_contentCd_GOV-SLM-PRO"
      id="ixv-24554">
          &#160;&#160;&#160;Year-to-Date Return
        </oef:YearToDateReturnLabel>
    <oef:BarChartYearToDateReturn
      contextRef="Pid_S000007070_contentCd_GOV-SLM-PRO"
      decimals="4"
      id="ixv-89799"
      unitRef="pure">0.0498</oef:BarChartYearToDateReturn>
    <oef:BarChartYearToDateReturnDate
      contextRef="Pid_S000007070_contentCd_GOV-SLM-PRO"
      id="ixv-24564">2025-09-30</oef:BarChartYearToDateReturnDate>
    <oef:PerformanceTableHeading
      contextRef="Pid_S000007070_contentCd_GOV-SLM-PRO"
      id="ixv-24569">


     Average Annual Returns


   </oef:PerformanceTableHeading>
    <oef:PerformanceTableNarrativeTextBlock
      contextRef="Pid_S000007070_contentCd_GOV-SLM-PRO"
      id="ixv-24574">




      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_S000007070_contentCd_GOV-SLM-PRO"
      id="ixv-24577">

      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_S000007070_contentCd_GOV-SLM-PRO"
      id="ixv-24584">

      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_S000007070_contentCd_GOV-SLM-PRO"
      id="ixv-24589">

      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_S000007070_Cid_C000019284_ReturnBeforeTaxes_01"
      id="ixv-24634">
         Return Before Taxes
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007070_Cid_C000019284_ReturnBeforeTaxes_01"
      decimals="4"
      id="ixv-89800"
      unitRef="pure">0.0224</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007070_Cid_C000019284_ReturnBeforeTaxes_05"
      decimals="4"
      id="ixv-89801"
      unitRef="pure">0.0006</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007070_Cid_C000019284_ReturnBeforeTaxes_10"
      decimals="4"
      id="ixv-89802"
      unitRef="pure">0.0089</oef:AvgAnnlRtrPct>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000007070_Cid_C000019284_AfterTaxesOnDistributions_01"
      id="ixv-24649">
         Return After Taxes on Distributions
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007070_Cid_C000019284_AfterTaxesOnDistributions_01"
      decimals="4"
      id="ixv-89803"
      unitRef="pure">0.0114</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007070_Cid_C000019284_AfterTaxesOnDistributions_05"
      decimals="4"
      id="ixv-89804"
      unitRef="pure">-0.0069</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007070_Cid_C000019284_AfterTaxesOnDistributions_10"
      decimals="4"
      id="ixv-89805"
      unitRef="pure">0.0015</oef:AvgAnnlRtrPct>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000007070_Cid_C000019284_AfterTaxesOnDistributionsAndSales_01"
      id="ixv-24665">
         Return After Taxes on Distributions and Sale of Fund Shares
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007070_Cid_C000019284_AfterTaxesOnDistributionsAndSales_01"
      decimals="4"
      id="ixv-89806"
      unitRef="pure">0.0143</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007070_Cid_C000019284_AfterTaxesOnDistributionsAndSales_05"
      decimals="4"
      id="ixv-89807"
      unitRef="pure">-0.0024</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007070_Cid_C000019284_AfterTaxesOnDistributionsAndSales_10"
      decimals="4"
      id="ixv-89808"
      unitRef="pure">0.0039</oef:AvgAnnlRtrPct>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000007070_Indexid_LB008_contentCd_GOV-SLM-PRO_01"
      id="ixv-24682">
         Bloomberg U.S. Intermediate Government Bond Index
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007070_Indexid_LB008_contentCd_GOV-SLM-PRO_01"
      decimals="4"
      id="ixv-89809"
      unitRef="pure">0.0244</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007070_Indexid_LB008_contentCd_GOV-SLM-PRO_05"
      decimals="4"
      id="ixv-89810"
      unitRef="pure">0.0049</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007070_Indexid_LB008_contentCd_GOV-SLM-PRO_10"
      decimals="4"
      id="ixv-89811"
      unitRef="pure">0.0124</oef:AvgAnnlRtrPct>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000007070_Indexid_LB001_contentCd_GOV-SLM-PRO_01"
      id="ixv-24707">
         Bloomberg U.S. Aggregate Bond Index
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007070_Indexid_LB001_contentCd_GOV-SLM-PRO_01"
      decimals="4"
      id="ixv-89812"
      unitRef="pure">0.0125</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007070_Indexid_LB001_contentCd_GOV-SLM-PRO_05"
      decimals="4"
      id="ixv-89813"
      unitRef="pure">-0.0033</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000007070_Indexid_LB001_contentCd_GOV-SLM-PRO_10"
      decimals="4"
      id="ixv-89814"
      unitRef="pure">0.0135</oef:AvgAnnlRtrPct>
    <oef:RiskReturnHeading
      contextRef="Pid_S000072130_contentCd_ENB-PRO"
      id="ixv-27680">


     Fund Summary

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

   </oef:RiskReturnHeading>
    <oef:ObjectiveHeading
      contextRef="Pid_S000072130_contentCd_ENB-PRO"
      id="ixv-27693">


     Investment Objective


   </oef:ObjectiveHeading>
    <oef:ObjectivePrimaryTextBlock
      contextRef="Pid_S000072130_contentCd_ENB-PRO"
      id="ixv-27698">


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


   </oef:ObjectivePrimaryTextBlock>
    <oef:ExpenseHeading
      contextRef="Pid_S000072130_contentCd_ENB-PRO"
      id="ixv-27703">


     Fee Table


   </oef:ExpenseHeading>
    <oef:ExpenseNarrativeTextBlock
      contextRef="Pid_S000072130_contentCd_ENB-PRO"
      id="ixv-27709">


     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_S000072130_contentCd_ENB-PRO"
      id="ixv-27720">


     Shareholder fees


   </oef:ShareholderFeesCaption>
    <oef:ShareholderFeeOther
      contextRef="Pid_S000072130_contentCd_ENB-PRO"
      decimals="0"
      id="ixv-89815"
      unitRef="usd">0</oef:ShareholderFeeOther>
    <oef:OperatingExpensesCaption
      contextRef="Pid_S000072130_contentCd_ENB-PRO"
      id="ixv-27735">


     Annual Operating Expenses


   </oef:OperatingExpensesCaption>
    <oef:ManagementFeesOverAssets
      contextRef="Pid_S000072130_Cid_C000227903"
      decimals="6"
      id="ixv-89816"
      unitRef="pure">0.0035</oef:ManagementFeesOverAssets>
    <oef:DistributionAndService12b1FeesOverAssets
      contextRef="Pid_S000072130_Cid_C000227903"
      decimals="6"
      id="ixv-89817"
      unitRef="pure">0</oef:DistributionAndService12b1FeesOverAssets>
    <oef:OtherExpensesOverAssets
      contextRef="Pid_S000072130_Cid_C000227903"
      decimals="6"
      id="ixv-89818"
      unitRef="pure">0.0010</oef:OtherExpensesOverAssets>
    <oef:ExpensesOverAssets
      contextRef="Pid_S000072130_Cid_C000227903"
      decimals="6"
      id="ixv-89819"
      unitRef="pure">0.0045</oef:ExpensesOverAssets>
    <oef:ExpenseExampleNarrativeTextBlock
      contextRef="Pid_S000072130_contentCd_ENB-PRO"
      id="ixv-27782">


     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_S000072130_Cid_C000227903"
      decimals="0"
      id="ixv-89820"
      unitRef="usd">46</oef:ExpenseExampleYear01>
    <oef:ExpenseExampleYear03
      contextRef="Pid_S000072130_Cid_C000227903"
      decimals="0"
      id="ixv-89821"
      unitRef="usd">144</oef:ExpenseExampleYear03>
    <oef:ExpenseExampleYear05
      contextRef="Pid_S000072130_Cid_C000227903"
      decimals="0"
      id="ixv-89822"
      unitRef="usd">252</oef:ExpenseExampleYear05>
    <oef:ExpenseExampleYear10
      contextRef="Pid_S000072130_Cid_C000227903"
      decimals="0"
      id="ixv-89823"
      unitRef="usd">567</oef:ExpenseExampleYear10>
    <oef:PortfolioTurnoverHeading
      contextRef="Pid_S000072130_contentCd_ENB-PRO"
      id="ixv-27839">


     Portfolio Turnover


   </oef:PortfolioTurnoverHeading>
    <oef:PortfolioTurnoverTextBlock
      contextRef="Pid_S000072130_contentCd_ENB-PRO"
      id="ixv-27844">


     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



       50


     % of the average value of its portfolio.


   </oef:PortfolioTurnoverTextBlock>
    <oef:PortfolioTurnoverRate
      contextRef="Pid_S000072130_contentCd_ENB-PRO"
      decimals="4"
      id="ixv-89824"
      unitRef="pure">0.50</oef:PortfolioTurnoverRate>
    <oef:StrategyHeading
      contextRef="Pid_S000072130_contentCd_ENB-PRO"
      id="ixv-27853">


     Principal Investment Strategies


   </oef:StrategyHeading>
    <oef:StrategyNarrativeTextBlock
      contextRef="Pid_S000072130_contentCd_ENB-PRO"
      id="ixv-27858">




        Normally investing at least 80% of assets in environmental debt securities of all types and repurchase agreements for those securities.
      Environmental debt securities include debt securities of issuers that develop or provide products or services that seek to provide environmental solutions and/or support efforts to reduce their own environmental footprint, and debt securities that support environmental projects. Environmental debt securities include issuers, including sovereign or government-related issuers, (i) contained in the Bloomberg MSCI Global Green Bond USD Index (Hedged USD) and/or (ii) that have an above average environmental score as categorized by MSCI or are rated low risk or better by Sustainalytics.

     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 investing primarily in investment-grade debt securities.
      Managing the fund with reference to the overall interest rate risk of the Bloomberg U.S. Aggregate Bond Index.
      Investing in domestic and foreign issuers.
      Allocating assets across different market sectors and maturities.
      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).
      Hedging the fund's foreign currency exposures utilizing forward foreign currency exchange contracts.
      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.
      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_S000072130_contentCd_ENB-PRO_RiskMember_EnvironmentalFocusRiskMember"
      id="ixv-27894">



      Environmental Focus Risk.

     The fund normally invests in issuers whose products or services are intended or likely to have a positive environmental impact. Some industries and sectors might be more likely to issue environmental bonds, and events or factors impacting these sectors may have a greater effect on, and may more adversely affect, the fund than they would a fund that does not invest in issuers with a common purpose. The fund also will be affected by a decrease in governmental or other support for environmental initiatives.

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000072130_contentCd_ENB-PRO_RiskMember_SustainabilityRiskMember"
      id="ixv-27903">



      Sustainability Risk.

     Application of Fidelity Management &amp; Research Company LLC's (FMR) (the Adviser) environmental, social and governance (ESG) ratings process and/or its sustainable investing exclusion criteria may affect the fund's exposure to certain issuers, sectors, regions, and countries and may affect the fund's performance 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_S000072130_contentCd_ENB-PRO_RiskMember_InterestRateChangesMember"
      id="ixv-27914">



      Interest Rate Changes.

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

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000072130_contentCd_ENB-PRO_RiskMember_ForeignExposureMember"
      id="ixv-27923">



      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.
     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.

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000072130_contentCd_ENB-PRO_RiskMember_ForeignCurrencyTransactionsMember"
      id="ixv-27936">



      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_S000072130_contentCd_ENB-PRO_RiskMember_PrepaymentMember"
      id="ixv-27945">



      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_S000072130_contentCd_ENB-PRO_RiskMember_IssuerSpecificChangesMember"
      id="ixv-27954">



      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_S000072130_contentCd_ENB-PRO_RiskMember_LeverageRiskMember"
      id="ixv-27971">



      Leverage Risk.

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



   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000072130_contentCd_ENB-PRO_RiskMember_RiskNotInsuredDepositoryInstitutionMember"
      id="ixv-27981">


     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_S000072130_contentCd_ENB-PRO_RiskMember_RiskLoseMoneyMember"
      id="ixv-27989">


     &#160;

     You could lose money by investing in the fund.


   </oef:RiskTextBlock>
    <oef:BarChartAndPerformanceTableHeading
      contextRef="Pid_S000072130_contentCd_ENB-PRO"
      id="ixv-27998">


     Performance


   </oef:BarChartAndPerformanceTableHeading>
    <oef:PerformanceNarrativeTextBlock
      contextRef="Pid_S000072130_contentCd_ENB-PRO"
      id="ixv-28003">



       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_S000072130_contentCd_ENB-PRO"
      id="ixv-28009">

      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_S000072130_contentCd_ENB-PRO"
      id="ixv-28018">

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

     </oef:PerformancePastDoesNotIndicateFuture>
    <oef:PerformanceAvailabilityWebSiteAddress
      contextRef="Pid_S000072130_contentCd_ENB-PRO"
      id="ixv-28024">

      www.fidelity.com
     </oef:PerformanceAvailabilityWebSiteAddress>
    <oef:BarChartHeading
      contextRef="Pid_S000072130_contentCd_ENB-PRO"
      id="ixv-28029">


     Year-by-Year Returns

   </oef:BarChartHeading>
    <oef:AnnlRtrPct
      contextRef="Pid_S000072130_Cid_C000227903_2022"
      decimals="INF"
      id="ixv-89825"
      unitRef="pure">-0.1366</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000072130_Cid_C000227903_2023"
      decimals="INF"
      id="ixv-89826"
      unitRef="pure">0.0567</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Pid_S000072130_Cid_C000227903_2024"
      decimals="INF"
      id="ixv-89827"
      unitRef="pure">0.0137</oef:AnnlRtrPct>
    <oef:HighestQuarterlyReturnLabel
      contextRef="Pid_S000072130_contentCd_ENB-PRO"
      id="ixv-28118">
          &#160;&#160;&#160;Highest Quarter Return
        </oef:HighestQuarterlyReturnLabel>
    <oef:BarChartHighestQuarterlyReturn
      contextRef="Pid_S000072130_contentCd_ENB-PRO"
      decimals="4"
      id="ixv-89828"
      unitRef="pure">0.0686</oef:BarChartHighestQuarterlyReturn>
    <oef:BarChartHighestQuarterlyReturnDate
      contextRef="Pid_S000072130_contentCd_ENB-PRO"
      id="ixv-28128">2023-12-31</oef:BarChartHighestQuarterlyReturnDate>
    <oef:LowestQuarterlyReturnLabel
      contextRef="Pid_S000072130_contentCd_ENB-PRO"
      id="ixv-28133">
          &#160;&#160;&#160;Lowest Quarter Return
        </oef:LowestQuarterlyReturnLabel>
    <oef:BarChartLowestQuarterlyReturn
      contextRef="Pid_S000072130_contentCd_ENB-PRO"
      decimals="4"
      id="ixv-89829"
      unitRef="pure">-0.0608</oef:BarChartLowestQuarterlyReturn>
    <oef:BarChartLowestQuarterlyReturnDate
      contextRef="Pid_S000072130_contentCd_ENB-PRO"
      id="ixv-28144">2022-06-30</oef:BarChartLowestQuarterlyReturnDate>
    <oef:YearToDateReturnLabel
      contextRef="Pid_S000072130_contentCd_ENB-PRO"
      id="ixv-28149">
          &#160;&#160;&#160;Year-to-Date Return
        </oef:YearToDateReturnLabel>
    <oef:BarChartYearToDateReturn
      contextRef="Pid_S000072130_contentCd_ENB-PRO"
      decimals="4"
      id="ixv-89830"
      unitRef="pure">0.0605</oef:BarChartYearToDateReturn>
    <oef:BarChartYearToDateReturnDate
      contextRef="Pid_S000072130_contentCd_ENB-PRO"
      id="ixv-28159">2025-09-30</oef:BarChartYearToDateReturnDate>
    <oef:PerformanceTableHeading
      contextRef="Pid_S000072130_contentCd_ENB-PRO"
      id="ixv-28164">


     Average Annual Returns


   </oef:PerformanceTableHeading>
    <oef:PerformanceTableNarrativeTextBlock
      contextRef="Pid_S000072130_contentCd_ENB-PRO"
      id="ixv-28169">




      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_S000072130_contentCd_ENB-PRO"
      id="ixv-28172">

      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_S000072130_contentCd_ENB-PRO"
      id="ixv-28179">

      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_S000072130_contentCd_ENB-PRO"
      id="ixv-28184">

      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_S000072130_Cid_C000227903_ReturnBeforeTaxes_01"
      id="ixv-28223">
         Return Before Taxes
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000072130_Cid_C000227903_ReturnBeforeTaxes_01"
      decimals="4"
      id="ixv-89831"
      unitRef="pure">0.0137</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000072130_Cid_C000227903_ReturnBeforeTaxes_AverageAnnualReturnSinceInception"
      decimals="4"
      id="footnoteENB-PROS000072130AAR_A_RBT_loc"
      unitRef="pure">-0.0221</oef:AvgAnnlRtrPct>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000072130_Cid_C000227903_AfterTaxesOnDistributions_01"
      id="ixv-28237">
         Return After Taxes on Distributions
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000072130_Cid_C000227903_AfterTaxesOnDistributions_01"
      decimals="4"
      id="ixv-89833"
      unitRef="pure">0.0000</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000072130_Cid_C000227903_AfterTaxesOnDistributions_AverageAnnualReturnSinceInception"
      decimals="4"
      id="footnoteENB-PROS000072130AAR_A_ATD_loc"
      unitRef="pure">-0.0331</oef:AvgAnnlRtrPct>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000072130_Cid_C000227903_AfterTaxesOnDistributionsAndSales_01"
      id="ixv-28251">
         Return After Taxes on Distributions and Sale of Fund Shares
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000072130_Cid_C000227903_AfterTaxesOnDistributionsAndSales_01"
      decimals="4"
      id="ixv-89835"
      unitRef="pure">0.0092</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000072130_Cid_C000227903_AfterTaxesOnDistributionsAndSales_AverageAnnualReturnSinceInception"
      decimals="4"
      id="footnoteENB-PROS000072130AAR_A_ATDS_loc"
      unitRef="pure">-0.0211</oef:AvgAnnlRtrPct>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000072130_Indexid_IXXY6_contentCd_ENB-PRO_01"
      id="ixv-28266">
         Bloomberg MSCI Global Green USD Bond Index (Hedged USD)
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000072130_Indexid_IXXY6_contentCd_ENB-PRO_01"
      decimals="4"
      id="ixv-89837"
      unitRef="pure">0.0301</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000072130_Indexid_IXXY6_contentCd_ENB-PRO_AverageAnnualReturnSinceInception"
      decimals="4"
      id="ixv-89838"
      unitRef="pure">-0.0106</oef:AvgAnnlRtrPct>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000072130_Indexid_LB001_contentCd_ENB-PRO_01"
      id="ixv-28286">
         Bloomberg U.S. Aggregate Bond Index
        </oef:AverageAnnualReturnLabel>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000072130_Indexid_LB001_contentCd_ENB-PRO_01"
      decimals="4"
      id="ixv-89839"
      unitRef="pure">0.0125</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000072130_Indexid_LB001_contentCd_ENB-PRO_AverageAnnualReturnSinceInception"
      decimals="4"
      id="ixv-89840"
      unitRef="pure">-0.0193</oef:AvgAnnlRtrPct>
    <oef:AnnualReturnInceptionDate contextRef="Pid_S000072130_Cid_C000227903" id="ixv-28319">2021-06-15</oef:AnnualReturnInceptionDate>
    <oef:RiskReturnHeading
      contextRef="Pid_S000072130_contentCd_AENB-PRO"
      id="ixv-30459">


     Fund Summary

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

   </oef:RiskReturnHeading>
    <oef:ObjectiveHeading
      contextRef="Pid_S000072130_contentCd_AENB-PRO"
      id="ixv-30474">


     Investment Objective


   </oef:ObjectiveHeading>
    <oef:ObjectivePrimaryTextBlock
      contextRef="Pid_S000072130_contentCd_AENB-PRO"
      id="ixv-30479">


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


   </oef:ObjectivePrimaryTextBlock>
    <oef:ExpenseHeading
      contextRef="Pid_S000072130_contentCd_AENB-PRO"
      id="ixv-30484">


     Fee Table


   </oef:ExpenseHeading>
    <oef:ExpenseNarrativeTextBlock
      contextRef="Pid_S000072130_contentCd_AENB-PRO"
      id="ixv-30490">


     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 40 of the prospectus



     and in

     the sales charge

     waiver appendix to

     the prospectus.

   </oef:ExpenseNarrativeTextBlock>
    <oef:ExpenseBreakpointDiscounts
      contextRef="Pid_S000072130_contentCd_AENB-PRO"
      id="ixv-30496">

      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 40 of the prospectus

     </oef:ExpenseBreakpointDiscounts>
    <oef:ExpenseBreakpointMinimumInvestmentRequiredAmount
      contextRef="Pid_S000072130_contentCd_AENB-PRO"
      decimals="0"
      id="ixv-89841"
      unitRef="usd">50000</oef:ExpenseBreakpointMinimumInvestmentRequiredAmount>
    <oef:ShareholderFeesCaption
      contextRef="Pid_S000072130_contentCd_AENB-PRO"
      id="ixv-30517">


     Shareholder fees


   </oef:ShareholderFeesCaption>
    <oef:MaximumCumulativeSalesChargeOverOfferingPrice
      contextRef="Pid_S000072130_Cid_C000227902"
      decimals="4"
      id="ixv-89842"
      unitRef="pure">0.0400</oef:MaximumCumulativeSalesChargeOverOfferingPrice>
    <oef:MaximumCumulativeSalesChargeOverOfferingPrice
      contextRef="Pid_S000072130_Cid_C000227901"
      decimals="4"
      id="ixv-89843"
      unitRef="pure">0.0400</oef:MaximumCumulativeSalesChargeOverOfferingPrice>
    <oef:MaximumCumulativeSalesChargeOverOfferingPrice
      contextRef="Pid_S000072130_Cid_C000227905"
      decimals="4"
      id="ixv-89844"
      unitRef="pure">0</oef:MaximumCumulativeSalesChargeOverOfferingPrice>
    <oef:MaximumCumulativeSalesChargeOverOfferingPrice
      contextRef="Pid_S000072130_Cid_C000227904"
      decimals="4"
      id="ixv-89845"
      unitRef="pure">0</oef:MaximumCumulativeSalesChargeOverOfferingPrice>
    <oef:MaximumCumulativeSalesChargeOverOfferingPrice
      contextRef="Pid_S000072130_Cid_C000227906"
      decimals="4"
      id="ixv-89846"
      unitRef="pure">0</oef:MaximumCumulativeSalesChargeOverOfferingPrice>
    <oef:MaximumDeferredSalesChargeOverOther
      contextRef="Pid_S000072130_Cid_C000227902"
      decimals="4"
      id="footnoteAENB-PROS000072130SHF_AC000227902"
      unitRef="pure">0</oef:MaximumDeferredSalesChargeOverOther>
    <oef:MaximumDeferredSalesChargeOverOther
      contextRef="Pid_S000072130_Cid_C000227901"
      decimals="4"
      id="footnoteAENB-PROS000072130SHF_AC000227901"
      unitRef="pure">0</oef:MaximumDeferredSalesChargeOverOther>
    <oef:MaximumDeferredSalesChargeOverOther
      contextRef="Pid_S000072130_Cid_C000227905"
      decimals="4"
      id="footnoteAENB-PROS000072130SHF_BC000227905"
      unitRef="pure">0.0100</oef:MaximumDeferredSalesChargeOverOther>
    <oef:MaximumDeferredSalesChargeOverOther
      contextRef="Pid_S000072130_Cid_C000227904"
      decimals="4"
      id="ixv-89850"
      unitRef="pure">0</oef:MaximumDeferredSalesChargeOverOther>
    <oef:MaximumDeferredSalesChargeOverOther
      contextRef="Pid_S000072130_Cid_C000227906"
      decimals="4"
      id="ixv-89851"
      unitRef="pure">0</oef:MaximumDeferredSalesChargeOverOther>
    <oef:ExpensesDeferredChargesTextBlock
      contextRef="Pid_S000072130_contentCd_AENB-PRO"
      id="ixv-30623">

      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_S000072130_Cid_C000227905" id="ixv-30633">

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

     </oef:ExpensesDeferredChargesTextBlock>
    <oef:OperatingExpensesCaption
      contextRef="Pid_S000072130_contentCd_AENB-PRO"
      id="ixv-30638">


     Annual Operating Expenses


   </oef:OperatingExpensesCaption>
    <oef:ManagementFeesOverAssets
      contextRef="Pid_S000072130_Cid_C000227902"
      decimals="6"
      id="ixv-89852"
      unitRef="pure">0.0035</oef:ManagementFeesOverAssets>
    <oef:ManagementFeesOverAssets
      contextRef="Pid_S000072130_Cid_C000227901"
      decimals="6"
      id="ixv-89853"
      unitRef="pure">0.0035</oef:ManagementFeesOverAssets>
    <oef:ManagementFeesOverAssets
      contextRef="Pid_S000072130_Cid_C000227905"
      decimals="6"
      id="ixv-89854"
      unitRef="pure">0.0035</oef:ManagementFeesOverAssets>
    <oef:ManagementFeesOverAssets
      contextRef="Pid_S000072130_Cid_C000227904"
      decimals="6"
      id="ixv-89855"
      unitRef="pure">0.0035</oef:ManagementFeesOverAssets>
    <oef:ManagementFeesOverAssets
      contextRef="Pid_S000072130_Cid_C000227906"
      decimals="6"
      id="ixv-89856"
      unitRef="pure">0.0035</oef:ManagementFeesOverAssets>
    <oef:DistributionAndService12b1FeesOverAssets
      contextRef="Pid_S000072130_Cid_C000227902"
      decimals="6"
      id="ixv-89857"
      unitRef="pure">0.0025</oef:DistributionAndService12b1FeesOverAssets>
    <oef:DistributionAndService12b1FeesOverAssets
      contextRef="Pid_S000072130_Cid_C000227901"
      decimals="6"
      id="ixv-89858"
      unitRef="pure">0.0025</oef:DistributionAndService12b1FeesOverAssets>
    <oef:DistributionAndService12b1FeesOverAssets
      contextRef="Pid_S000072130_Cid_C000227905"
      decimals="6"
      id="ixv-89859"
      unitRef="pure">0.0100</oef:DistributionAndService12b1FeesOverAssets>
    <oef:DistributionAndService12b1FeesOverAssets
      contextRef="Pid_S000072130_Cid_C000227904"
      decimals="6"
      id="ixv-89860"
      unitRef="pure">0</oef:DistributionAndService12b1FeesOverAssets>
    <oef:DistributionAndService12b1FeesOverAssets
      contextRef="Pid_S000072130_Cid_C000227906"
      decimals="6"
      id="ixv-89861"
      unitRef="pure">0</oef:DistributionAndService12b1FeesOverAssets>
    <oef:OtherExpensesOverAssets
      contextRef="Pid_S000072130_Cid_C000227902"
      decimals="6"
      id="ixv-89862"
      unitRef="pure">0.0009</oef:OtherExpensesOverAssets>
    <oef:OtherExpensesOverAssets
      contextRef="Pid_S000072130_Cid_C000227901"
      decimals="6"
      id="ixv-89863"
      unitRef="pure">0.0007</oef:OtherExpensesOverAssets>
    <oef:OtherExpensesOverAssets
      contextRef="Pid_S000072130_Cid_C000227905"
      decimals="6"
      id="ixv-89864"
      unitRef="pure">0.0009</oef:OtherExpensesOverAssets>
    <oef:OtherExpensesOverAssets
      contextRef="Pid_S000072130_Cid_C000227904"
      decimals="6"
      id="ixv-89865"
      unitRef="pure">0.0023</oef:OtherExpensesOverAssets>
    <oef:OtherExpensesOverAssets
      contextRef="Pid_S000072130_Cid_C000227906"
      decimals="6"
      id="ixv-89866"
      unitRef="pure">0.0005</oef:OtherExpensesOverAssets>
    <oef:ExpensesOverAssets
      contextRef="Pid_S000072130_Cid_C000227902"
      decimals="6"
      id="ixv-89867"
      unitRef="pure">0.0069</oef:ExpensesOverAssets>
    <oef:ExpensesOverAssets
      contextRef="Pid_S000072130_Cid_C000227901"
      decimals="6"
      id="ixv-89868"
      unitRef="pure">0.0067</oef:ExpensesOverAssets>
    <oef:ExpensesOverAssets
      contextRef="Pid_S000072130_Cid_C000227905"
      decimals="6"
      id="ixv-89869"
      unitRef="pure">0.0144</oef:ExpensesOverAssets>
    <oef:ExpensesOverAssets
      contextRef="Pid_S000072130_Cid_C000227904"
      decimals="6"
      id="ixv-89870"
      unitRef="pure">0.0058</oef:ExpensesOverAssets>
    <oef:ExpensesOverAssets
      contextRef="Pid_S000072130_Cid_C000227906"
      decimals="6"
      id="ixv-89871"
      unitRef="pure">0.0040</oef:ExpensesOverAssets>
    <oef:FeeWaiverOrReimbursementOverAssets
      contextRef="Pid_S000072130_Cid_C000227902"
      decimals="6"
      id="ixv-89872"
      unitRef="pure">-0.0000</oef:FeeWaiverOrReimbursementOverAssets>
    <oef:FeeWaiverOrReimbursementOverAssets
      contextRef="Pid_S000072130_Cid_C000227901"
      decimals="6"
      id="ixv-89873"
      unitRef="pure">-0.0000</oef:FeeWaiverOrReimbursementOverAssets>
    <oef:FeeWaiverOrReimbursementOverAssets
      contextRef="Pid_S000072130_Cid_C000227905"
      decimals="6"
      id="ixv-89874"
      unitRef="pure">-0.0000</oef:FeeWaiverOrReimbursementOverAssets>
    <oef:FeeWaiverOrReimbursementOverAssets
      contextRef="Pid_S000072130_Cid_C000227904"
      decimals="6"
      id="footnoteS000072130AENB-PROAOE_AC000227904_FW"
      unitRef="pure">-0.0013</oef:FeeWaiverOrReimbursementOverAssets>
    <oef:FeeWaiverOrReimbursementOverAssets
      contextRef="Pid_S000072130_Cid_C000227906"
      decimals="6"
      id="footnoteS000072130AENB-PROAOE_AC000227906_FW"
      unitRef="pure">-0.0004</oef:FeeWaiverOrReimbursementOverAssets>
    <oef:NetExpensesOverAssets
      contextRef="Pid_S000072130_Cid_C000227902"
      decimals="6"
      id="ixv-89877"
      unitRef="pure">0.0069</oef:NetExpensesOverAssets>
    <oef:NetExpensesOverAssets
      contextRef="Pid_S000072130_Cid_C000227901"
      decimals="6"
      id="ixv-89878"
      unitRef="pure">0.0067</oef:NetExpensesOverAssets>
    <oef:NetExpensesOverAssets
      contextRef="Pid_S000072130_Cid_C000227905"
      decimals="6"
      id="ixv-89879"
      unitRef="pure">0.0144</oef:NetExpensesOverAssets>
    <oef:NetExpensesOverAssets
      contextRef="Pid_S000072130_Cid_C000227904"
      decimals="6"
      id="ixv-89880"
      unitRef="pure">0.0045</oef:NetExpensesOverAssets>
    <oef:NetExpensesOverAssets
      contextRef="Pid_S000072130_Cid_C000227906"
      decimals="6"
      id="ixv-89881"
      unitRef="pure">0.0036</oef:NetExpensesOverAssets>
    <oef:FeeWaiverOrReimbursementOverAssetsDateOfTermination
      contextRef="Pid_S000072130_contentCd_AENB-PRO"
      id="ixv-30877">2026-12-31</oef:FeeWaiverOrReimbursementOverAssetsDateOfTermination>
    <oef:ExpenseExampleNarrativeTextBlock
      contextRef="Pid_S000072130_contentCd_AENB-PRO"
      id="ixv-30890">


     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_S000072130_Cid_C000227902"
      decimals="0"
      id="ixv-89882"
      unitRef="usd">468</oef:ExpenseExampleYear01>
    <oef:ExpenseExampleNoRedemptionYear01
      contextRef="Pid_S000072130_Cid_C000227902"
      decimals="0"
      id="ixv-89883"
      unitRef="usd">468</oef:ExpenseExampleNoRedemptionYear01>
    <oef:ExpenseExampleYear01
      contextRef="Pid_S000072130_Cid_C000227901"
      decimals="0"
      id="ixv-89884"
      unitRef="usd">466</oef:ExpenseExampleYear01>
    <oef:ExpenseExampleNoRedemptionYear01
      contextRef="Pid_S000072130_Cid_C000227901"
      decimals="0"
      id="ixv-89885"
      unitRef="usd">466</oef:ExpenseExampleNoRedemptionYear01>
    <oef:ExpenseExampleYear01
      contextRef="Pid_S000072130_Cid_C000227905"
      decimals="0"
      id="ixv-89886"
      unitRef="usd">247</oef:ExpenseExampleYear01>
    <oef:ExpenseExampleNoRedemptionYear01
      contextRef="Pid_S000072130_Cid_C000227905"
      decimals="0"
      id="ixv-89887"
      unitRef="usd">147</oef:ExpenseExampleNoRedemptionYear01>
    <oef:ExpenseExampleYear01
      contextRef="Pid_S000072130_Cid_C000227904"
      decimals="0"
      id="ixv-89888"
      unitRef="usd">46</oef:ExpenseExampleYear01>
    <oef:ExpenseExampleNoRedemptionYear01
      contextRef="Pid_S000072130_Cid_C000227904"
      decimals="0"
      id="ixv-89889"
      unitRef="usd">46</oef:ExpenseExampleNoRedemptionYear01>
    <oef:ExpenseExampleYear01
      contextRef="Pid_S000072130_Cid_C000227906"
      decimals="0"
      id="ixv-89890"
      unitRef="usd">37</oef:ExpenseExampleYear01>
    <oef:ExpenseExampleNoRedemptionYear01
      contextRef="Pid_S000072130_Cid_C000227906"
      decimals="0"
      id="ixv-89891"
      unitRef="usd">37</oef:ExpenseExampleNoRedemptionYear01>
    <oef:ExpenseExampleYear03
      contextRef="Pid_S000072130_Cid_C000227902"
      decimals="0"
      id="ixv-89892"
      unitRef="usd">612</oef:ExpenseExampleYear03>
    <oef:ExpenseExampleNoRedemptionYear03
      contextRef="Pid_S000072130_Cid_C000227902"
      decimals="0"
      id="ixv-89893"
      unitRef="usd">612</oef:ExpenseExampleNoRedemptionYear03>
    <oef:ExpenseExampleYear03
      contextRef="Pid_S000072130_Cid_C000227901"
      decimals="0"
      id="ixv-89894"
      unitRef="usd">606</oef:ExpenseExampleYear03>
    <oef:ExpenseExampleNoRedemptionYear03
      contextRef="Pid_S000072130_Cid_C000227901"
      decimals="0"
      id="ixv-89895"
      unitRef="usd">606</oef:ExpenseExampleNoRedemptionYear03>
    <oef:ExpenseExampleYear03
      contextRef="Pid_S000072130_Cid_C000227905"
      decimals="0"
      id="ixv-89896"
      unitRef="usd">456</oef:ExpenseExampleYear03>
    <oef:ExpenseExampleNoRedemptionYear03
      contextRef="Pid_S000072130_Cid_C000227905"
      decimals="0"
      id="ixv-89897"
      unitRef="usd">456</oef:ExpenseExampleNoRedemptionYear03>
    <oef:ExpenseExampleYear03
      contextRef="Pid_S000072130_Cid_C000227904"
      decimals="0"
      id="ixv-89898"
      unitRef="usd">168</oef:ExpenseExampleYear03>
    <oef:ExpenseExampleNoRedemptionYear03
      contextRef="Pid_S000072130_Cid_C000227904"
      decimals="0"
      id="ixv-89899"
      unitRef="usd">168</oef:ExpenseExampleNoRedemptionYear03>
    <oef:ExpenseExampleYear03
      contextRef="Pid_S000072130_Cid_C000227906"
      decimals="0"
      id="ixv-89900"
      unitRef="usd">123</oef:ExpenseExampleYear03>
    <oef:ExpenseExampleNoRedemptionYear03
      contextRef="Pid_S000072130_Cid_C000227906"
      decimals="0"
      id="ixv-89901"
      unitRef="usd">123</oef:ExpenseExampleNoRedemptionYear03>
    <oef:ExpenseExampleYear05
      contextRef="Pid_S000072130_Cid_C000227902"
      decimals="0"
      id="ixv-89902"
      unitRef="usd">769</oef:ExpenseExampleYear05>
    <oef:ExpenseExampleNoRedemptionYear05
      contextRef="Pid_S000072130_Cid_C000227902"
      decimals="0"
      id="ixv-89903"
      unitRef="usd">769</oef:ExpenseExampleNoRedemptionYear05>
    <oef:ExpenseExampleYear05
      contextRef="Pid_S000072130_Cid_C000227901"
      decimals="0"
      id="ixv-89904"
      unitRef="usd">758</oef:ExpenseExampleYear05>
    <oef:ExpenseExampleNoRedemptionYear05
      contextRef="Pid_S000072130_Cid_C000227901"
      decimals="0"
      id="ixv-89905"
      unitRef="usd">758</oef:ExpenseExampleNoRedemptionYear05>
    <oef:ExpenseExampleYear05
      contextRef="Pid_S000072130_Cid_C000227905"
      decimals="0"
      id="ixv-89906"
      unitRef="usd">787</oef:ExpenseExampleYear05>
    <oef:ExpenseExampleNoRedemptionYear05
      contextRef="Pid_S000072130_Cid_C000227905"
      decimals="0"
      id="ixv-89907"
      unitRef="usd">787</oef:ExpenseExampleNoRedemptionYear05>
    <oef:ExpenseExampleYear05
      contextRef="Pid_S000072130_Cid_C000227904"
      decimals="0"
      id="ixv-89908"
      unitRef="usd">306</oef:ExpenseExampleYear05>
    <oef:ExpenseExampleNoRedemptionYear05
      contextRef="Pid_S000072130_Cid_C000227904"
      decimals="0"
      id="ixv-89909"
      unitRef="usd">306</oef:ExpenseExampleNoRedemptionYear05>
    <oef:ExpenseExampleYear05
      contextRef="Pid_S000072130_Cid_C000227906"
      decimals="0"
      id="ixv-89910"
      unitRef="usd">219</oef:ExpenseExampleYear05>
    <oef:ExpenseExampleNoRedemptionYear05
      contextRef="Pid_S000072130_Cid_C000227906"
      decimals="0"
      id="ixv-89911"
      unitRef="usd">219</oef:ExpenseExampleNoRedemptionYear05>
    <oef:ExpenseExampleYear10
      contextRef="Pid_S000072130_Cid_C000227902"
      decimals="0"
      id="ixv-89912"
      unitRef="usd">1224</oef:ExpenseExampleYear10>
    <oef:ExpenseExampleNoRedemptionYear10
      contextRef="Pid_S000072130_Cid_C000227902"
      decimals="0"
      id="ixv-89913"
      unitRef="usd">1224</oef:ExpenseExampleNoRedemptionYear10>
    <oef:ExpenseExampleYear10
      contextRef="Pid_S000072130_Cid_C000227901"
      decimals="0"
      id="ixv-89914"
      unitRef="usd">1201</oef:ExpenseExampleYear10>
    <oef:ExpenseExampleNoRedemptionYear10
      contextRef="Pid_S000072130_Cid_C000227901"
      decimals="0"
      id="ixv-89915"
      unitRef="usd">1201</oef:ExpenseExampleNoRedemptionYear10>
    <oef:ExpenseExampleYear10
      contextRef="Pid_S000072130_Cid_C000227905"
      decimals="0"
      id="ixv-89916"
      unitRef="usd">1520</oef:ExpenseExampleYear10>
    <oef:ExpenseExampleNoRedemptionYear10
      contextRef="Pid_S000072130_Cid_C000227905"
      decimals="0"
      id="ixv-89917"
      unitRef="usd">1520</oef:ExpenseExampleNoRedemptionYear10>
    <oef:ExpenseExampleYear10
      contextRef="Pid_S000072130_Cid_C000227904"
      decimals="0"
      id="ixv-89918"
      unitRef="usd">709</oef:ExpenseExampleYear10>
    <oef:ExpenseExampleNoRedemptionYear10
      contextRef="Pid_S000072130_Cid_C000227904"
      decimals="0"
      id="ixv-89919"
      unitRef="usd">709</oef:ExpenseExampleNoRedemptionYear10>
    <oef:ExpenseExampleYear10
      contextRef="Pid_S000072130_Cid_C000227906"
      decimals="0"
      id="ixv-89920"
      unitRef="usd">500</oef:ExpenseExampleYear10>
    <oef:ExpenseExampleNoRedemptionYear10
      contextRef="Pid_S000072130_Cid_C000227906"
      decimals="0"
      id="ixv-89921"
      unitRef="usd">500</oef:ExpenseExampleNoRedemptionYear10>
    <oef:PortfolioTurnoverHeading
      contextRef="Pid_S000072130_contentCd_AENB-PRO"
      id="ixv-31198">


     Portfolio Turnover


   </oef:PortfolioTurnoverHeading>
    <oef:PortfolioTurnoverTextBlock
      contextRef="Pid_S000072130_contentCd_AENB-PRO"
      id="ixv-31203">


     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



       50


     % of the average value of its portfolio.


   </oef:PortfolioTurnoverTextBlock>
    <oef:PortfolioTurnoverRate
      contextRef="Pid_S000072130_contentCd_AENB-PRO"
      decimals="4"
      id="ixv-89922"
      unitRef="pure">0.50</oef:PortfolioTurnoverRate>
    <oef:StrategyHeading
      contextRef="Pid_S000072130_contentCd_AENB-PRO"
      id="ixv-31212">


     Principal Investment Strategies


   </oef:StrategyHeading>
    <oef:StrategyNarrativeTextBlock
      contextRef="Pid_S000072130_contentCd_AENB-PRO"
      id="ixv-31217">




        Normally investing at least 80% of assets in environmental debt securities of all types and repurchase agreements for those securities.
      Environmental debt securities include debt securities of issuers that develop or provide products or services that seek to provide environmental solutions and/or support efforts to reduce their own environmental footprint, and debt securities that support environmental projects. Environmental debt securities include issuers, including sovereign or government-related issuers, (i) contained in the Bloomberg MSCI Global Green Bond USD Index (Hedged USD) and/or (ii) that have an above average environmental score as categorized by MSCI or are rated low risk or better by Sustainalytics.

     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 investing primarily in investment-grade debt securities.
      Managing the fund with reference to the overall interest rate risk of the Bloomberg U.S. Aggregate Bond Index.
      Investing in domestic and foreign issuers.
      Allocating assets across different market sectors and maturities.
      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).
      Hedging the fund's foreign currency exposures utilizing forward foreign currency exchange contracts.
      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.
      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_S000072130_contentCd_AENB-PRO_RiskMember_EnvironmentalFocusRiskMember"
      id="ixv-31253">



      Environmental Focus Risk.

     The fund normally invests in issuers whose products or services are intended or likely to have a positive environmental impact. Some industries and sectors might be more likely to issue environmental bonds, and events or factors impacting these sectors may have a greater effect on, and may more adversely affect, the fund than they would a fund that does not invest in issuers with a common purpose. The fund also will be affected by a decrease in governmental or other support for environmental initiatives.

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000072130_contentCd_AENB-PRO_RiskMember_SustainabilityRiskMember"
      id="ixv-31262">



      Sustainability Risk.

     Application of Fidelity Management &amp; Research Company LLC's (FMR) (the Adviser) environmental, social and governance (ESG) ratings process and/or its sustainable investing exclusion criteria may affect the fund's exposure to certain issuers, sectors, regions, and countries and may affect the fund's performance 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_S000072130_contentCd_AENB-PRO_RiskMember_InterestRateChangesMember"
      id="ixv-31273">



      Interest Rate Changes.

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

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000072130_contentCd_AENB-PRO_RiskMember_ForeignExposureMember"
      id="ixv-31282">



      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.
     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.

   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000072130_contentCd_AENB-PRO_RiskMember_ForeignCurrencyTransactionsMember"
      id="ixv-31295">



      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_S000072130_contentCd_AENB-PRO_RiskMember_PrepaymentMember"
      id="ixv-31304">



      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_S000072130_contentCd_AENB-PRO_RiskMember_IssuerSpecificChangesMember"
      id="ixv-31313">



      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_S000072130_contentCd_AENB-PRO_RiskMember_LeverageRiskMember"
      id="ixv-31330">



      Leverage Risk.

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



   </oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Pid_S000072130_contentCd_AENB-PRO_RiskMember_RiskNotInsuredDepositoryInstitutionMember"
      id="ixv-31340">


     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_S000072130_contentCd_AENB-PRO_RiskMember_RiskLoseMoneyMember"
      id="ixv-31348">


     &#160;

     You could lose money by investing in the fund.


   </oef:RiskTextBlock>
    <oef:BarChartAndPerformanceTableHeading
      contextRef="Pid_S000072130_contentCd_AENB-PRO"
      id="ixv-31357">


     Performance


   </oef:BarChartAndPerformanceTableHeading>
    <oef:PerformanceNarrativeTextBlock
      contextRef="Pid_S000072130_contentCd_AENB-PRO"
      id="ixv-31362">



       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_S000072130_contentCd_AENB-PRO"
      id="ixv-31368">

      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_S000072130_contentCd_AENB-PRO"
      id="ixv-31377">

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

     </oef:PerformancePastDoesNotIndicateFuture>
    <oef:PerformanceAvailabilityWebSiteAddress
      contextRef="Pid_S000072130_contentCd_AENB-PRO"
      id="ixv-31383">

      institutional.fidelity.com
     </oef:PerformanceAvailabilityWebSiteAddress>
    <oef:BarChartHeading
      contextRef="Pid_S000072130_contentCd_AENB-PRO"
      id="ixv-31388">


     Year-by-Year Returns

   </oef:BarChartHeading>
    <oef:BarChartNarrativeTextBlock
      contextRef="Pid_S000072130_contentCd_AENB-PRO"
      id="ixv-31392">




      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
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      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.

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      contextRef="Pid_S000072130_Cid_C000227902_2022"
      decimals="INF"
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      contextRef="Pid_S000072130_Cid_C000227902_2023"
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      contextRef="Pid_S000072130_Cid_C000227902_2024"
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          &#160;&#160;&#160;Highest Quarter Return
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      contextRef="Pid_S000072130_contentCd_AENB-PRO"
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          &#160;&#160;&#160;Lowest Quarter Return
        </oef:LowestQuarterlyReturnLabel>
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      contextRef="Pid_S000072130_contentCd_AENB-PRO"
      decimals="4"
      id="ixv-89927"
      unitRef="pure">-0.0613</oef:BarChartLowestQuarterlyReturn>
    <oef:BarChartLowestQuarterlyReturnDate
      contextRef="Pid_S000072130_contentCd_AENB-PRO"
      id="ixv-31511">2022-06-30</oef:BarChartLowestQuarterlyReturnDate>
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      contextRef="Pid_S000072130_contentCd_AENB-PRO"
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          &#160;&#160;&#160;Year-to-Date Return
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      contextRef="Pid_S000072130_contentCd_AENB-PRO"
      decimals="4"
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      unitRef="pure">0.0585</oef:BarChartYearToDateReturn>
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      contextRef="Pid_S000072130_contentCd_AENB-PRO"
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      contextRef="Pid_S000072130_contentCd_AENB-PRO"
      id="ixv-31531">


     Average Annual Returns


   </oef:PerformanceTableHeading>
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      contextRef="Pid_S000072130_contentCd_AENB-PRO"
      id="ixv-31537">




      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.




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    <oef:PerformanceTableUsesHighestFederalRate
      contextRef="Pid_S000072130_contentCd_AENB-PRO"
      id="ixv-31545">

      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.

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      contextRef="Pid_S000072130_contentCd_AENB-PRO"
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      After-tax returns for Class A are shown in the table below and after-tax returns for other classes will vary.

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      contextRef="Pid_S000072130_contentCd_AENB-PRO"
      id="ixv-31556">

      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).
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      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.

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      contextRef="Pid_S000072130_Cid_C000227902_ReturnBeforeTaxes_01"
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         Return Before Taxes
        </oef:AverageAnnualReturnLabel>
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      contextRef="Pid_S000072130_Cid_C000227902_ReturnBeforeTaxes_01"
      decimals="4"
      id="ixv-89929"
      unitRef="pure">-0.0292</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
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      unitRef="pure">-0.0356</oef:AvgAnnlRtrPct>
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         Return After Taxes on Distributions
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      contextRef="Pid_S000072130_Cid_C000227902_AfterTaxesOnDistributions_01"
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      unitRef="pure">-0.0408</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Pid_S000072130_Cid_C000227902_AfterTaxesOnDistributions_AverageAnnualReturnSinceInception"
      decimals="4"
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      unitRef="pure">-0.0453</oef:AvgAnnlRtrPct>
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          Return After Taxes on Distributions and Sale of Fund Shares
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      contextRef="Pid_S000072130_Cid_C000227902_AfterTaxesOnDistributionsAndSales_01"
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      unitRef="pure">-0.0157</oef:AvgAnnlRtrPct>
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      unitRef="pure">-0.0306</oef:AvgAnnlRtrPct>
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         Return Before Taxes
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      unitRef="pure">-0.0279</oef:AvgAnnlRtrPct>
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         Return Before Taxes
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         Return Before Taxes
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         Return Before Taxes
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      unitRef="pure">-0.0212</oef:AvgAnnlRtrPct>
    <oef:AverageAnnualReturnLabel
      contextRef="Pid_S000072130_Indexid_IXXY6_contentCd_AENB-PRO_01"
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         Bloomberg MSCI Global Green USD Bond Index (Hedged USD)
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    <oef:AvgAnnlRtrPct
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    <oef:AverageAnnualReturnLabel
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         Bloomberg U.S. Aggregate Bond Index
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    <oef:AvgAnnlRtrPct
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    <oef:AvgAnnlRtrPct
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    <oef:AnnualReturnInceptionDate contextRef="Pid_S000072130_Cid_C000227902" id="ixv-31743">2021-06-15</oef:AnnualReturnInceptionDate>
    <oef:AnnualReturnInceptionDate contextRef="Pid_S000072130_Cid_C000227901" id="ixv-31757">2021-06-15</oef:AnnualReturnInceptionDate>
    <oef:AnnualReturnInceptionDate contextRef="Pid_S000072130_Cid_C000227905" id="ixv-31770">2021-06-15</oef:AnnualReturnInceptionDate>
    <oef:AnnualReturnInceptionDate contextRef="Pid_S000072130_Cid_C000227904" id="ixv-31783">2021-06-15</oef:AnnualReturnInceptionDate>
    <oef:AnnualReturnInceptionDate contextRef="Pid_S000072130_Cid_C000227906" id="ixv-31796">2021-06-15</oef:AnnualReturnInceptionDate>
    <link:footnoteLink
      xlink:role="http://www.xbrl.org/2003/role/link"
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        <link:footnote id="footnoteTBDK6-PROS000057288AAR_A" xlink:label="footnoteTBDK6-PROS000057288AAR_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 25, 2017</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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        <link:loc
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        <link:footnote id="footnoteATB-PROS000007066SHF_A" xlink:label="footnoteATB-PROS000007066SHF_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>
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        <link:loc
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        <link:footnote id="footnoteATB-PROS000007066SHF_B" xlink:label="footnoteATB-PROS000007066SHF_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:footnote id="footnoteS000007066ATB-PROAOE_A" xlink:label="footnoteS000007066ATB-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 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
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      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>
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        <link:footnote id="footnoteXGB-PROS000062811AAR_A" xlink:label="footnoteXGB-PROS000062811AAR_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">August 17, 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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        <link:loc
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        <link:footnote id="footnoteAGVT-PROS000007069SHF_A" xlink:label="footnoteAGVT-PROS000007069SHF_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>
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          xlink:href="#footnoteAGVT-PROS000007069SHF_AC000038101"
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        <link:loc
          xlink:href="#footnoteAGVT-PROS000007069SHF_BC000038100"
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        <link:footnote id="footnoteAGVT-PROS000007069SHF_B" xlink:label="footnoteAGVT-PROS000007069SHF_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:arcrole="http://www.xbrl.org/2003/arcrole/fact-footnote"
          xlink:from="footnoteAGVT-PROS000007069SHF_BC000038100"
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          xlink:type="arc"/>
        <link:loc
          xlink:href="#footnoteS000007069AGVT-PROAOE_AC000205069_FW"
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        <link:footnote id="footnoteS000007069AGVT-PROAOE_A" xlink:label="footnoteS000007069AGVT-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"
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       </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>
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          xlink:href="#footnoteAGVT-PROS000007069AAR_A_RBT_loc"
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        <link:footnote id="footnoteAGVT-PROS000007069AAR_A" xlink:label="footnoteAGVT-PROS000007069AAR_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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        <link:loc
          xlink:href="#footnoteENB-PROS000072130AAR_A_RBT_loc"
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          xlink:type="locator"/>
        <link:footnote id="footnoteENB-PROS000072130AAR_A" xlink:label="footnoteENB-PROS000072130AAR_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">June 15, 2021</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="footnoteENB-PROS000072130AAR_A"
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        <link:loc
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          xlink:type="arc"/>
        <link:loc
          xlink:href="#footnoteENB-PROS000072130AAR_A_ATDS_loc"
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        <link:footnoteArc
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        <link:loc
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        <link:footnote id="footnoteAENB-PROS000072130SHF_A" xlink:label="footnoteAENB-PROS000072130SHF_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:from="footnoteAENB-PROS000072130SHF_AC000227902"
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        <link:loc
          xlink:href="#footnoteAENB-PROS000072130SHF_AC000227901"
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        <link:footnoteArc
          xlink:arcrole="http://www.xbrl.org/2003/arcrole/fact-footnote"
          xlink:from="footnoteAENB-PROS000072130SHF_AC000227901"
          xlink:to="footnoteAENB-PROS000072130SHF_A"
          xlink:type="arc"/>
        <link:loc
          xlink:href="#footnoteAENB-PROS000072130SHF_BC000227905"
          xlink:label="footnoteAENB-PROS000072130SHF_BC000227905"
          xlink:type="locator"/>
        <link:footnote id="footnoteAENB-PROS000072130SHF_B" xlink:label="footnoteAENB-PROS000072130SHF_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>
        <link:footnoteArc
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          xlink:from="footnoteAENB-PROS000072130SHF_BC000227905"
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          xlink:type="arc"/>
        <link:loc
          xlink:href="#footnoteS000072130AENB-PROAOE_AC000227904_FW"
          xlink:label="footnoteS000072130AENB-PROAOE_AC000227904_FW"
          xlink:type="locator"/>
        <link:footnote id="footnoteS000072130AENB-PROAOE_A" xlink:label="footnoteS000072130AENB-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 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 0.45% and 0.36% (the Expense Caps). If at any time during the current fiscal year expenses for 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>
        <link:footnoteArc
          xlink:arcrole="http://www.xbrl.org/2003/arcrole/fact-footnote"
          xlink:from="footnoteS000072130AENB-PROAOE_AC000227904_FW"
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        <link:loc
          xlink:href="#footnoteS000072130AENB-PROAOE_AC000227906_FW"
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        <link:footnoteArc
          xlink:arcrole="http://www.xbrl.org/2003/arcrole/fact-footnote"
          xlink:from="footnoteS000072130AENB-PROAOE_AC000227906_FW"
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        <link:loc
          xlink:href="#footnoteAENB-PROS000072130AAR_A_RBT_loc"
          xlink:label="footnoteAENB-PROS000072130AAR_A_RBT_loc"
          xlink:type="locator"/>
        <link:footnote id="footnoteAENB-PROS000072130AAR_A" xlink:label="footnoteAENB-PROS000072130AAR_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; ">June 15, 2021</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="footnoteAENB-PROS000072130AAR_A_RBT_loc"
          xlink:to="footnoteAENB-PROS000072130AAR_A"
          xlink:type="arc"/>
        <link:loc
          xlink:href="#footnoteAENB-PROS000072130AAR_A_ATD_loc"
          xlink:label="footnoteAENB-PROS000072130AAR_A_ATD_loc"
          xlink:type="locator"/>
        <link:footnoteArc
          xlink:arcrole="http://www.xbrl.org/2003/arcrole/fact-footnote"
          xlink:from="footnoteAENB-PROS000072130AAR_A_ATD_loc"
          xlink:to="footnoteAENB-PROS000072130AAR_A"
          xlink:type="arc"/>
        <link:loc
          xlink:href="#footnoteAENB-PROS000072130AAR_A_ATDS_loc"
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          xlink:type="locator"/>
        <link:footnoteArc
          xlink:arcrole="http://www.xbrl.org/2003/arcrole/fact-footnote"
          xlink:from="footnoteAENB-PROS000072130AAR_A_ATDS_loc"
          xlink:to="footnoteAENB-PROS000072130AAR_A"
          xlink:type="arc"/>
        <link:loc
          xlink:href="#footnoteAENB-PROS000072130AAR_B_RBT_loc"
          xlink:label="footnoteAENB-PROS000072130AAR_B_RBT_loc"
          xlink:type="locator"/>
        <link:footnote id="footnoteAENB-PROS000072130AAR_B" xlink:label="footnoteAENB-PROS000072130AAR_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; ">June 15, 2021</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="footnoteAENB-PROS000072130AAR_B_RBT_loc"
          xlink:to="footnoteAENB-PROS000072130AAR_B"
          xlink:type="arc"/>
        <link:loc
          xlink:href="#footnoteAENB-PROS000072130AAR_C_RBT_loc"
          xlink:label="footnoteAENB-PROS000072130AAR_C_RBT_loc"
          xlink:type="locator"/>
        <link:footnote id="footnoteAENB-PROS000072130AAR_C" xlink:label="footnoteAENB-PROS000072130AAR_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; ">June 15, 2021</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="footnoteAENB-PROS000072130AAR_C_RBT_loc"
          xlink:to="footnoteAENB-PROS000072130AAR_C"
          xlink:type="arc"/>
        <link:loc
          xlink:href="#footnoteAENB-PROS000072130AAR_D_RBT_loc"
          xlink:label="footnoteAENB-PROS000072130AAR_D_RBT_loc"
          xlink:type="locator"/>
        <link:footnote id="footnoteAENB-PROS000072130AAR_D" xlink:label="footnoteAENB-PROS000072130AAR_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; ">June 15, 2021</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="footnoteAENB-PROS000072130AAR_D_RBT_loc"
          xlink:to="footnoteAENB-PROS000072130AAR_D"
          xlink:type="arc"/>
        <link:loc
          xlink:href="#footnoteAENB-PROS000072130AAR_E_RBT_loc"
          xlink:label="footnoteAENB-PROS000072130AAR_E_RBT_loc"
          xlink:type="locator"/>
        <link:footnote id="footnoteAENB-PROS000072130AAR_E" xlink:label="footnoteAENB-PROS000072130AAR_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; ">June 15, 2021</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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