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        <measure>iso4217:USD</measure>
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        <measure>pure</measure>
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    <dei:DocumentType contextRef="Trust">485BPOS</dei:DocumentType>
    <dei:DocumentPeriodEndDate contextRef="Trust">2022-10-31</dei:DocumentPeriodEndDate>
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    <dei:EntityRegistrantName contextRef="Trust">Fidelity Salem Street Trust</dei:EntityRegistrantName>
    <rr:RiskReturnHeading contextRef="S000056355ZEI-PRO">
  Fund Summary

   Fund:



    Fidelity Flex&#xae; International Index Fund



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    <rr:ObjectiveHeading contextRef="S000056355ZEI-PRO">
  Investment Objective
 </rr:ObjectiveHeading>
    <rr:ObjectivePrimaryTextBlock contextRef="S000056355ZEI-PRO">
  Fidelity Flex&#xae; International Index Fund seeks to provide investment results that correspond to the total return of foreign developed and emerging stock markets.
 </rr:ObjectivePrimaryTextBlock>
    <rr:ExpenseHeading contextRef="S000056355ZEI-PRO">
  Fee Table
 </rr:ExpenseHeading>
    <rr:ExpenseNarrativeTextBlock contextRef="S000056355ZEI-PRO">

   The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund.
   In addition to the fees and expenses described below, your broker may also require you to pay brokerage commissions on purchases and sales of the fund.


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    <rr:ShareholderFeesCaption contextRef="S000056355ZEI-PRO">
  Shareholder fees
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    <rr:ShareholderFeeOther contextRef="S000056355ZEI-PRO" decimals="0" unitRef="usd">0</rr:ShareholderFeeOther>
    <rr:OperatingExpensesCaption contextRef="S000056355ZEI-PRO">
  Annual Operating Expenses
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    <rr:ManagementFeesOverAssets
      contextRef="S000056355C000177582"
      decimals="6"
      unitRef="pure">0</rr:ManagementFeesOverAssets>
    <rr:DistributionAndService12b1FeesOverAssets
      contextRef="S000056355C000177582"
      decimals="6"
      unitRef="pure">0</rr:DistributionAndService12b1FeesOverAssets>
    <rr:OtherExpensesOverAssets
      contextRef="S000056355C000177582"
      decimals="6"
      unitRef="pure">0.0000</rr:OtherExpensesOverAssets>
    <rr:ExpensesOverAssets
      contextRef="S000056355C000177582"
      decimals="6"
      id="footnoteZEI-PROAOE_A_TE"
      unitRef="pure">0.0000</rr:ExpensesOverAssets>
    <rr:ExpenseExampleNarrativeTextBlock contextRef="S000056355ZEI-PRO">
  This
  example
   helps compare the cost of investing in the fund with the cost of investing in other funds.

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

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    <rr:ExpenseExampleYear01
      contextRef="S000056355C000177582"
      decimals="0"
      unitRef="usd">0</rr:ExpenseExampleYear01>
    <rr:ExpenseExampleYear03
      contextRef="S000056355C000177582"
      decimals="0"
      unitRef="usd">0</rr:ExpenseExampleYear03>
    <rr:ExpenseExampleYear05
      contextRef="S000056355C000177582"
      decimals="0"
      unitRef="usd">0</rr:ExpenseExampleYear05>
    <rr:ExpenseExampleYear10
      contextRef="S000056355C000177582"
      decimals="0"
      unitRef="usd">0</rr:ExpenseExampleYear10>
    <rr:PortfolioTurnoverHeading contextRef="S000056355ZEI-PRO">
  Portfolio Turnover
 </rr:PortfolioTurnoverHeading>
    <rr:PortfolioTurnoverTextBlock contextRef="S000056355ZEI-PRO">
  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

    4

  % of the average value of its portfolio.
 </rr:PortfolioTurnoverTextBlock>
    <rr:PortfolioTurnoverRate contextRef="S000056355ZEI-PRO" decimals="4" unitRef="pure">0.04</rr:PortfolioTurnoverRate>
    <rr:StrategyHeading contextRef="S000056355ZEI-PRO">
  Principal Investment Strategies
 </rr:StrategyHeading>
    <rr:StrategyNarrativeTextBlock contextRef="S000056355ZEI-PRO">

   Normally investing at least 80% of assets in securities included in the MSCI ACWI (All Country World Index) ex USA Index and in depositary receipts representing securities included in the index. The MSCI ACWI (All Country World Index) ex USA Index is a market capitalization-weighted index designed to measure the investable equity market performance for global investors of developed and emerging markets, excluding the United States.
   Using statistical sampling techniques based on such factors as capitalization, industry exposures, dividend yield, price/earnings (P/E) ratio, price/book (P/B) ratio, earnings growth, country weightings, and the effect of foreign taxes to attempt to replicate the returns of the MSCI ACWI (All Country World Index) ex USA Index.
   Lending securities to earn income for the fund.


 </rr:StrategyNarrativeTextBlock>
    <rr:RiskHeading contextRef="S000056355ZEI-PRO">
  Principal Investment Risks
 </rr:RiskHeading>
    <rr:RiskNarrativeTextBlock contextRef="S000056355ZEI-PRO">

   Stock Market Volatility.


   Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.


   Foreign and Emerging Markets Risk.


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


   The extent of economic development; political stability; market depth, infrastructure, and capitalization; and regulatory oversight can be less than in more developed markets. Emerging markets typically have less established legal, accounting and financial reporting systems than those in more developed markets, which may reduce the scope or quality of financial information available to investors.


   Emerging markets can be subject to greater social, economic, regulatory, and political uncertainties and can be extremely volatile.


   Foreign exchange rates also can be extremely volatile.


   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.


   Changes in the financial condition of an issuer or counterparty (e.g., broker-dealer or other borrower in a securities lending transaction) can increase the risk of default by an issuer or counterparty, which can affect a security's or instrument's value or result in delays in recovering securities and/or capital from a counterparty.


   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.


   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.


   Securities Lending Risk.


   Securities lending involves the risk that the borrower may fail to return the securities loaned in a timely manner or at all. If the borrower defaults on its obligation to return the securities loaned because of insolvency or other reasons, a fund could experience delays and costs in recovering the securities loaned or in gaining access to the collateral.



    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
    .


    &#160;
    You could lose money by investing in the fund.



 </rr:RiskNarrativeTextBlock>
    <rr:RiskNotInsuredDepositoryInstitution contextRef="S000056355ZEI-PRO">
    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
    .
   </rr:RiskNotInsuredDepositoryInstitution>
    <rr:RiskLoseMoney contextRef="S000056355ZEI-PRO">
    &#160;
    You could lose money by investing in the fund.
   </rr:RiskLoseMoney>
    <rr:BarChartAndPerformanceTableHeading contextRef="S000056355ZEI-PRO">
  Performance
 </rr:BarChartAndPerformanceTableHeading>
    <rr:PerformanceNarrativeTextBlock contextRef="S000056355ZEI-PRO">

   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.



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


   Visit

     www.401k.com

   and log in for more recent performance information.


 </rr:PerformanceNarrativeTextBlock>
    <rr:PerformanceInformationIllustratesVariabilityOfReturns contextRef="S000056355ZEI-PRO">
    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.
   </rr:PerformanceInformationIllustratesVariabilityOfReturns>
    <rr:PerformancePastDoesNotIndicateFuture contextRef="S000056355ZEI-PRO">
     Past performance (before and after taxes) is not an indication of future performance.
   </rr:PerformancePastDoesNotIndicateFuture>
    <rr:PerformanceAvailabilityWebSiteAddress contextRef="S000056355ZEI-PRO">
     www.401k.com
   </rr:PerformanceAvailabilityWebSiteAddress>
    <rr:BarChartHeading contextRef="S000056355ZEI-PRO">
  Year-by-Year Returns
 </rr:BarChartHeading>
    <rr:AnnualReturn2018
      contextRef="S000056355C000177582"
      decimals="INF"
      unitRef="pure">-0.1395</rr:AnnualReturn2018>
    <rr:AnnualReturn2019
      contextRef="S000056355C000177582"
      decimals="INF"
      unitRef="pure">0.2142</rr:AnnualReturn2019>
    <rr:AnnualReturn2020
      contextRef="S000056355C000177582"
      decimals="INF"
      unitRef="pure">0.1076</rr:AnnualReturn2020>
    <rr:AnnualReturn2021
      contextRef="S000056355C000177582"
      decimals="INF"
      unitRef="pure">0.0778</rr:AnnualReturn2021>
    <rr:HighestQuarterlyReturnLabel contextRef="S000056355ZEI-PRO">
      &#160;&#160;&#160;Highest Quarter Return
    </rr:HighestQuarterlyReturnLabel>
    <rr:BarChartHighestQuarterlyReturn contextRef="S000056355ZEI-PRO" decimals="4" unitRef="pure">0.1681</rr:BarChartHighestQuarterlyReturn>
    <rr:BarChartHighestQuarterlyReturnDate contextRef="S000056355ZEI-PRO">2020-06-30</rr:BarChartHighestQuarterlyReturnDate>
    <rr:LowestQuarterlyReturnLabel contextRef="S000056355ZEI-PRO">
      &#160;&#160;&#160;Lowest Quarter Return
    </rr:LowestQuarterlyReturnLabel>
    <rr:BarChartLowestQuarterlyReturn contextRef="S000056355ZEI-PRO" decimals="4" unitRef="pure">-0.2347</rr:BarChartLowestQuarterlyReturn>
    <rr:BarChartLowestQuarterlyReturnDate contextRef="S000056355ZEI-PRO">2020-03-31</rr:BarChartLowestQuarterlyReturnDate>
    <rr:YearToDateReturnLabel contextRef="S000056355ZEI-PRO">
      &#160;&#160;&#160;Year-to-Date Return
    </rr:YearToDateReturnLabel>
    <rr:BarChartYearToDateReturn contextRef="S000056355ZEI-PRO" decimals="4" unitRef="pure">-0.2672</rr:BarChartYearToDateReturn>
    <rr:BarChartYearToDateReturnDate contextRef="S000056355ZEI-PRO">2022-09-30</rr:BarChartYearToDateReturnDate>
    <rr:PerformanceTableHeading contextRef="S000056355ZEI-PRO">
  Average Annual Returns
 </rr:PerformanceTableHeading>
    <rr:PerformanceTableNarrativeTextBlock contextRef="S000056355ZEI-PRO">

   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.

 </rr:PerformanceTableNarrativeTextBlock>
    <rr:PerformanceTableUsesHighestFederalRate contextRef="S000056355ZEI-PRO">
   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.
  </rr:PerformanceTableUsesHighestFederalRate>
    <rr:PerformanceTableNotRelevantToTaxDeferred contextRef="S000056355ZEI-PRO">
    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).
  </rr:PerformanceTableNotRelevantToTaxDeferred>
    <rr:PerformanceTableExplanationAfterTaxHigher contextRef="S000056355ZEI-PRO">
    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.
  </rr:PerformanceTableExplanationAfterTaxHigher>
    <rr:AverageAnnualReturnLabel contextRef="S000056355C000177582ReturnBeforeTaxes">
     Return Before Taxes
    </rr:AverageAnnualReturnLabel>
    <rr:AverageAnnualReturnYear01
      contextRef="S000056355C000177582ReturnBeforeTaxes"
      decimals="4"
      unitRef="pure">0.0778</rr:AverageAnnualReturnYear01>
    <rr:AverageAnnualReturnSinceInception
      contextRef="S000056355C000177582ReturnBeforeTaxes"
      decimals="4"
      id="footnoteZEI-PROS000056355AAR__RBT"
      unitRef="pure">0.0893</rr:AverageAnnualReturnSinceInception>
    <rr:AverageAnnualReturnLabel contextRef="S000056355C000177582AfterTaxesOnDistributions">
     Return After Taxes on Distributions
    </rr:AverageAnnualReturnLabel>
    <rr:AverageAnnualReturnYear01
      contextRef="S000056355C000177582AfterTaxesOnDistributions"
      decimals="4"
      unitRef="pure">0.0724</rr:AverageAnnualReturnYear01>
    <rr:AverageAnnualReturnSinceInception
      contextRef="S000056355C000177582AfterTaxesOnDistributions"
      decimals="4"
      id="footnoteZEI-PROS000056355AAR__ATD"
      unitRef="pure">0.0847</rr:AverageAnnualReturnSinceInception>
    <rr:AverageAnnualReturnLabel contextRef="S000056355C000177582AfterTaxesOnDistributionsAndSales">
     Return After Taxes on Distributions and Sale of Fund Shares
    </rr:AverageAnnualReturnLabel>
    <rr:AverageAnnualReturnYear01
      contextRef="S000056355C000177582AfterTaxesOnDistributionsAndSales"
      decimals="4"
      unitRef="pure">0.0504</rr:AverageAnnualReturnYear01>
    <rr:AverageAnnualReturnSinceInception
      contextRef="S000056355C000177582AfterTaxesOnDistributionsAndSales"
      decimals="4"
      id="footnoteZEI-PROS000056355AAR__ATDS"
      unitRef="pure">0.0705</rr:AverageAnnualReturnSinceInception>
    <rr:AverageAnnualReturnLabel contextRef="S000056355IndexMS112ZEI-PRO">
     MSCI ACWI (All Country World Index) ex USA Index
    </rr:AverageAnnualReturnLabel>
    <rr:AverageAnnualReturnYear01
      contextRef="S000056355IndexMS112ZEI-PRO"
      decimals="4"
      unitRef="pure">0.0798</rr:AverageAnnualReturnYear01>
    <rr:AverageAnnualReturnSinceInception
      contextRef="S000056355IndexMS112ZEI-PRO"
      decimals="4"
      id="footnoteZEI-PROS000056355AAR_A_IndexMS112"
      unitRef="pure">0.0915</rr:AverageAnnualReturnSinceInception>
    <rr:AnnualReturnInceptionDate contextRef="S000056355ZEI-PRO">2017-03-09</rr:AnnualReturnInceptionDate>
    <rr:RiskReturnHeading contextRef="S000033635EMX-I-GUX-I-PRO">
  Fund Summary

   Fund:



    Fidelity&#xae; Emerging Markets Index Fund



 </rr:RiskReturnHeading>
    <rr:ObjectiveHeading contextRef="S000033635EMX-I-GUX-I-PRO">
  Investment Objective
 </rr:ObjectiveHeading>
    <rr:ObjectivePrimaryTextBlock contextRef="S000033635EMX-I-GUX-I-PRO">
  Fidelity&#xae; Emerging Markets Index Fund seeks to provide investment results that correspond to the total return of emerging stock markets.
 </rr:ObjectivePrimaryTextBlock>
    <rr:ExpenseHeading contextRef="S000033635EMX-I-GUX-I-PRO">
  Fee Table
 </rr:ExpenseHeading>
    <rr:ExpenseNarrativeTextBlock contextRef="S000033635EMX-I-GUX-I-PRO">

   The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund.
   In addition to the fees and expenses described below, your broker may also require you to pay brokerage commissions on purchases and sales of the fund.


 </rr:ExpenseNarrativeTextBlock>
    <rr:ShareholderFeesCaption contextRef="S000033635EMX-I-GUX-I-PRO">
  Shareholder fees
 </rr:ShareholderFeesCaption>
    <rr:ShareholderFeeOther
      contextRef="S000033635EMX-I-GUX-I-PRO"
      decimals="0"
      unitRef="usd">0</rr:ShareholderFeeOther>
    <rr:OperatingExpensesCaption contextRef="S000033635EMX-I-GUX-I-PRO">
  Annual Operating Expenses
 </rr:OperatingExpensesCaption>
    <rr:ManagementFeesOverAssets
      contextRef="S000033635C000103361"
      decimals="6"
      unitRef="pure">0.00075</rr:ManagementFeesOverAssets>
    <rr:DistributionAndService12b1FeesOverAssets
      contextRef="S000033635C000103361"
      decimals="6"
      unitRef="pure">0</rr:DistributionAndService12b1FeesOverAssets>
    <rr:OtherExpensesOverAssets
      contextRef="S000033635C000103361"
      decimals="6"
      unitRef="pure">0.00000</rr:OtherExpensesOverAssets>
    <rr:ExpensesOverAssets
      contextRef="S000033635C000103361"
      decimals="6"
      unitRef="pure">0.00075</rr:ExpensesOverAssets>
    <rr:ExpenseExampleNarrativeTextBlock contextRef="S000033635EMX-I-GUX-I-PRO">
  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:
 </rr:ExpenseExampleNarrativeTextBlock>
    <rr:ExpenseExampleYear01
      contextRef="S000033635C000103361"
      decimals="0"
      unitRef="usd">8</rr:ExpenseExampleYear01>
    <rr:ExpenseExampleYear03
      contextRef="S000033635C000103361"
      decimals="0"
      unitRef="usd">24</rr:ExpenseExampleYear03>
    <rr:ExpenseExampleYear05
      contextRef="S000033635C000103361"
      decimals="0"
      unitRef="usd">42</rr:ExpenseExampleYear05>
    <rr:ExpenseExampleYear10
      contextRef="S000033635C000103361"
      decimals="0"
      unitRef="usd">96</rr:ExpenseExampleYear10>
    <rr:PortfolioTurnoverHeading contextRef="S000033635EMX-I-GUX-I-PRO">
   Portfolio Turnover
  </rr:PortfolioTurnoverHeading>
    <rr:PortfolioTurnoverTextBlock contextRef="S000033635EMX-I-GUX-I-PRO">
   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

     8

   % of the average value of its portfolio.
  </rr:PortfolioTurnoverTextBlock>
    <rr:PortfolioTurnoverRate
      contextRef="S000033635EMX-I-GUX-I-PRO"
      decimals="4"
      unitRef="pure">0.08</rr:PortfolioTurnoverRate>
    <rr:StrategyHeading contextRef="S000033635EMX-I-GUX-I-PRO">
   Principal Investment Strategies
  </rr:StrategyHeading>
    <rr:StrategyNarrativeTextBlock contextRef="S000033635EMX-I-GUX-I-PRO">

    Normally investing at least 80% of assets in securities included in the MSCI Emerging Markets Index and in depositary receipts representing securities included in the index.
    Using statistical sampling techniques based on such factors as capitalization, industry exposures, dividend yield, price/earnings (P/E) ratio, price/book (P/B) ratio, earnings growth, country weightings, and the effect of foreign taxes to attempt to replicate the returns of the MSCI Emerging Markets Index.
    Lending securities to earn income for the fund.


  </rr:StrategyNarrativeTextBlock>
    <rr:RiskHeading contextRef="S000033635EMX-I-GUX-I-PRO">
   Principal Investment Risks
  </rr:RiskHeading>
    <rr:RiskNarrativeTextBlock contextRef="S000033635EMX-I-GUX-I-PRO">

    Stock Market Volatility.


    Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.


    Foreign and Emerging Markets Risk.


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


    The extent of economic development; political stability; market depth, infrastructure, and capitalization; and regulatory oversight can be less than in more developed markets. Emerging markets typically have less established legal, accounting and financial reporting systems than those in more developed markets, which may reduce the scope or quality of financial information available to investors.


    Emerging markets can be subject to greater social, economic, regulatory, and political uncertainties and can be extremely volatile.


    Foreign exchange rates also can be extremely volatile.


    Geographic Exposure to China.


    Because the fund invests a meaningful portion of its assets in China, the fund's performance is expected to be closely tied to social, political, and economic conditions in China and to be more volatile than the performance of more geographically diversified funds. The fund may obtain exposure to companies based or operated in China by investing through legal structures known as variable interest entities (VIEs). Instead of directly owning the equity securities of a Chinese company, a VIE enters into service and other contracts with the Chinese company. Although the VIE has no equity ownership of the Chinese company, the contractual arrangements permit the VIE to consolidate the Chinese company into its financial statements. Intervention by the Chinese government with respect to VIEs could significantly affect the Chinese company's performance and the enforceability of the VIE's contractual arrangements with the Chinese company.


    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.


    Changes in the financial condition of an issuer or counterparty (e.g., broker-dealer or other borrower in a securities lending transaction) can increase the risk of default by an issuer or counterparty, which can affect a security's or instrument's value or result in delays in recovering securities and/or capital from a counterparty.


    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.


    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.


    Securities Lending Risk.


    Securities lending involves the risk that the borrower may fail to return the securities loaned in a timely manner or at all. If the borrower defaults on its obligation to return the securities loaned because of insolvency or other reasons, a fund could experience delays and costs in recovering the securities loaned or in gaining access to the collateral.



     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
     .


     &#160;
     You could lose money by investing in the fund.



  </rr:RiskNarrativeTextBlock>
    <rr:RiskNotInsuredDepositoryInstitution contextRef="S000033635EMX-I-GUX-I-PRO">
     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
     .
    </rr:RiskNotInsuredDepositoryInstitution>
    <rr:RiskLoseMoney contextRef="S000033635EMX-I-GUX-I-PRO">
     &#160;
     You could lose money by investing in the fund.
    </rr:RiskLoseMoney>
    <rr:BarChartAndPerformanceTableHeading contextRef="S000033635EMX-I-GUX-I-PRO">
   Performance
  </rr:BarChartAndPerformanceTableHeading>
    <rr:PerformanceNarrativeTextBlock contextRef="S000033635EMX-I-GUX-I-PRO">

    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 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.



    Prior to May 4, 2016, the fund compared its performance to a different benchmark. The fund's historical performance may not represent its current investment policies.


    Visit

      www.fidelity.com

    for more recent performance information.


  </rr:PerformanceNarrativeTextBlock>
    <rr:PerformanceInformationIllustratesVariabilityOfReturns contextRef="S000033635EMX-I-GUX-I-PRO">
     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.
    </rr:PerformanceInformationIllustratesVariabilityOfReturns>
    <rr:PerformancePastDoesNotIndicateFuture contextRef="S000033635EMX-I-GUX-I-PRO">
      Past performance (before and after taxes) is not an indication of future performance.
    </rr:PerformancePastDoesNotIndicateFuture>
    <rr:PerformanceAvailabilityWebSiteAddress contextRef="S000033635EMX-I-GUX-I-PRO">
      www.fidelity.com
    </rr:PerformanceAvailabilityWebSiteAddress>
    <rr:BarChartHeading contextRef="S000033635EMX-I-GUX-I-PRO">
   Year-by-Year Returns
  </rr:BarChartHeading>
    <rr:AnnualReturn2012
      contextRef="S000033635C000103361"
      decimals="INF"
      unitRef="pure">0.1762</rr:AnnualReturn2012>
    <rr:AnnualReturn2013
      contextRef="S000033635C000103361"
      decimals="INF"
      unitRef="pure">-0.0469</rr:AnnualReturn2013>
    <rr:AnnualReturn2014
      contextRef="S000033635C000103361"
      decimals="INF"
      unitRef="pure">0.0059</rr:AnnualReturn2014>
    <rr:AnnualReturn2015
      contextRef="S000033635C000103361"
      decimals="INF"
      unitRef="pure">-0.1584</rr:AnnualReturn2015>
    <rr:AnnualReturn2016
      contextRef="S000033635C000103361"
      decimals="INF"
      unitRef="pure">0.1126</rr:AnnualReturn2016>
    <rr:AnnualReturn2017
      contextRef="S000033635C000103361"
      decimals="INF"
      unitRef="pure">0.3765</rr:AnnualReturn2017>
    <rr:AnnualReturn2018
      contextRef="S000033635C000103361"
      decimals="INF"
      unitRef="pure">-0.1463</rr:AnnualReturn2018>
    <rr:AnnualReturn2019
      contextRef="S000033635C000103361"
      decimals="INF"
      unitRef="pure">0.1826</rr:AnnualReturn2019>
    <rr:AnnualReturn2020
      contextRef="S000033635C000103361"
      decimals="INF"
      unitRef="pure">0.1782</rr:AnnualReturn2020>
    <rr:AnnualReturn2021
      contextRef="S000033635C000103361"
      decimals="INF"
      unitRef="pure">-0.0304</rr:AnnualReturn2021>
    <rr:HighestQuarterlyReturnLabel contextRef="S000033635EMX-I-GUX-I-PRO">
       &#160;&#160;&#160;Highest Quarter Return
     </rr:HighestQuarterlyReturnLabel>
    <rr:BarChartHighestQuarterlyReturn
      contextRef="S000033635EMX-I-GUX-I-PRO"
      decimals="4"
      unitRef="pure">0.1880</rr:BarChartHighestQuarterlyReturn>
    <rr:BarChartHighestQuarterlyReturnDate contextRef="S000033635EMX-I-GUX-I-PRO">2020-12-31</rr:BarChartHighestQuarterlyReturnDate>
    <rr:LowestQuarterlyReturnLabel contextRef="S000033635EMX-I-GUX-I-PRO">
       &#160;&#160;&#160;Lowest Quarter Return
     </rr:LowestQuarterlyReturnLabel>
    <rr:BarChartLowestQuarterlyReturn
      contextRef="S000033635EMX-I-GUX-I-PRO"
      decimals="4"
      unitRef="pure">-0.2386</rr:BarChartLowestQuarterlyReturn>
    <rr:BarChartLowestQuarterlyReturnDate contextRef="S000033635EMX-I-GUX-I-PRO">2020-03-31</rr:BarChartLowestQuarterlyReturnDate>
    <rr:YearToDateReturnLabel contextRef="S000033635EMX-I-GUX-I-PRO">
       &#160;&#160;&#160;Year-to-Date Return
     </rr:YearToDateReturnLabel>
    <rr:BarChartYearToDateReturn
      contextRef="S000033635EMX-I-GUX-I-PRO"
      decimals="4"
      unitRef="pure">-0.2721</rr:BarChartYearToDateReturn>
    <rr:BarChartYearToDateReturnDate contextRef="S000033635EMX-I-GUX-I-PRO">2022-09-30</rr:BarChartYearToDateReturnDate>
    <rr:PerformanceTableHeading contextRef="S000033635EMX-I-GUX-I-PRO">
   Average Annual Returns
  </rr:PerformanceTableHeading>
    <rr:PerformanceTableNarrativeTextBlock contextRef="S000033635EMX-I-GUX-I-PRO">

    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.

  </rr:PerformanceTableNarrativeTextBlock>
    <rr:PerformanceTableUsesHighestFederalRate contextRef="S000033635EMX-I-GUX-I-PRO">
    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.
   </rr:PerformanceTableUsesHighestFederalRate>
    <rr:PerformanceTableNotRelevantToTaxDeferred contextRef="S000033635EMX-I-GUX-I-PRO">
     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).
   </rr:PerformanceTableNotRelevantToTaxDeferred>
    <rr:PerformanceTableExplanationAfterTaxHigher contextRef="S000033635EMX-I-GUX-I-PRO">
     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.
   </rr:PerformanceTableExplanationAfterTaxHigher>
    <rr:AverageAnnualReturnLabel contextRef="S000033635C000103361ReturnBeforeTaxes">
      Return Before Taxes
     </rr:AverageAnnualReturnLabel>
    <rr:AverageAnnualReturnYear01
      contextRef="S000033635C000103361ReturnBeforeTaxes"
      decimals="4"
      unitRef="pure">-0.0304</rr:AverageAnnualReturnYear01>
    <rr:AverageAnnualReturnYear05
      contextRef="S000033635C000103361ReturnBeforeTaxes"
      decimals="4"
      unitRef="pure">0.0969</rr:AverageAnnualReturnYear05>
    <rr:AverageAnnualReturnYear10
      contextRef="S000033635C000103361ReturnBeforeTaxes"
      decimals="4"
      unitRef="pure">0.0530</rr:AverageAnnualReturnYear10>
    <rr:AverageAnnualReturnLabel contextRef="S000033635C000103361AfterTaxesOnDistributions">
      Return After Taxes on Distributions
     </rr:AverageAnnualReturnLabel>
    <rr:AverageAnnualReturnYear01
      contextRef="S000033635C000103361AfterTaxesOnDistributions"
      decimals="4"
      unitRef="pure">-0.0358</rr:AverageAnnualReturnYear01>
    <rr:AverageAnnualReturnYear05
      contextRef="S000033635C000103361AfterTaxesOnDistributions"
      decimals="4"
      unitRef="pure">0.0914</rr:AverageAnnualReturnYear05>
    <rr:AverageAnnualReturnYear10
      contextRef="S000033635C000103361AfterTaxesOnDistributions"
      decimals="4"
      unitRef="pure">0.0481</rr:AverageAnnualReturnYear10>
    <rr:AverageAnnualReturnLabel contextRef="S000033635C000103361AfterTaxesOnDistributionsAndSales">
      Return After Taxes on Distributions and Sale of Fund Shares
     </rr:AverageAnnualReturnLabel>
    <rr:AverageAnnualReturnYear01
      contextRef="S000033635C000103361AfterTaxesOnDistributionsAndSales"
      decimals="4"
      unitRef="pure">-0.0151</rr:AverageAnnualReturnYear01>
    <rr:AverageAnnualReturnYear05
      contextRef="S000033635C000103361AfterTaxesOnDistributionsAndSales"
      decimals="4"
      unitRef="pure">0.0762</rr:AverageAnnualReturnYear05>
    <rr:AverageAnnualReturnYear10
      contextRef="S000033635C000103361AfterTaxesOnDistributionsAndSales"
      decimals="4"
      unitRef="pure">0.0417</rr:AverageAnnualReturnYear10>
    <rr:AverageAnnualReturnLabel contextRef="S000033635IndexMC041EMX-I-GUX-I-PRO">
      MSCI Emerging Markets Index
     </rr:AverageAnnualReturnLabel>
    <rr:AverageAnnualReturnYear01
      contextRef="S000033635IndexMC041EMX-I-GUX-I-PRO"
      decimals="4"
      unitRef="pure">-0.0253</rr:AverageAnnualReturnYear01>
    <rr:AverageAnnualReturnYear05
      contextRef="S000033635IndexMC041EMX-I-GUX-I-PRO"
      decimals="4"
      unitRef="pure">0.0990</rr:AverageAnnualReturnYear05>
    <rr:AverageAnnualReturnYear10
      contextRef="S000033635IndexMC041EMX-I-GUX-I-PRO"
      decimals="4"
      unitRef="pure">0.0553</rr:AverageAnnualReturnYear10>
    <rr:AverageAnnualReturnLabel contextRef="S000033635IndexIXZ94EMX-I-GUX-I-PRO">
      Fidelity Emerging Markets Index Fund Linked Index&#x2120;
     </rr:AverageAnnualReturnLabel>
    <rr:AverageAnnualReturnYear01
      contextRef="S000033635IndexIXZ94EMX-I-GUX-I-PRO"
      decimals="4"
      unitRef="pure">-0.0253</rr:AverageAnnualReturnYear01>
    <rr:AverageAnnualReturnYear05
      contextRef="S000033635IndexIXZ94EMX-I-GUX-I-PRO"
      decimals="4"
      unitRef="pure">0.0990</rr:AverageAnnualReturnYear05>
    <rr:AverageAnnualReturnYear10
      contextRef="S000033635IndexIXZ94EMX-I-GUX-I-PRO"
      decimals="4"
      unitRef="pure">0.0579</rr:AverageAnnualReturnYear10>
    <rr:RiskReturnHeading contextRef="S000033636EMX-I-GUX-I-PRO">
   Fund Summary

    Fund:



     Fidelity&#xae; Global ex U.S. Index Fund



  </rr:RiskReturnHeading>
    <rr:ObjectiveHeading contextRef="S000033636EMX-I-GUX-I-PRO">
   Investment Objective
  </rr:ObjectiveHeading>
    <rr:ObjectivePrimaryTextBlock contextRef="S000033636EMX-I-GUX-I-PRO">
   Fidelity&#xae; Global ex U.S. Index Fund seeks to provide investment results that correspond to the total return of foreign developed and emerging stock markets.
  </rr:ObjectivePrimaryTextBlock>
    <rr:ExpenseHeading contextRef="S000033636EMX-I-GUX-I-PRO">
   Fee Table
  </rr:ExpenseHeading>
    <rr:ExpenseNarrativeTextBlock contextRef="S000033636EMX-I-GUX-I-PRO">

    The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund.
    In addition to the fees and expenses described below, your broker may also require you to pay brokerage commissions on purchases and sales of the fund.


  </rr:ExpenseNarrativeTextBlock>
    <rr:ShareholderFeesCaption contextRef="S000033636EMX-I-GUX-I-PRO">
   Shareholder fees
  </rr:ShareholderFeesCaption>
    <rr:ShareholderFeeOther
      contextRef="S000033636EMX-I-GUX-I-PRO"
      decimals="0"
      unitRef="usd">0</rr:ShareholderFeeOther>
    <rr:OperatingExpensesCaption contextRef="S000033636EMX-I-GUX-I-PRO">
   Annual Operating Expenses
  </rr:OperatingExpensesCaption>
    <rr:ManagementFeesOverAssets
      contextRef="S000033636C000103365"
      decimals="6"
      unitRef="pure">0.00055</rr:ManagementFeesOverAssets>
    <rr:DistributionAndService12b1FeesOverAssets
      contextRef="S000033636C000103365"
      decimals="6"
      unitRef="pure">0</rr:DistributionAndService12b1FeesOverAssets>
    <rr:OtherExpensesOverAssets
      contextRef="S000033636C000103365"
      decimals="6"
      unitRef="pure">0.00000</rr:OtherExpensesOverAssets>
    <rr:ExpensesOverAssets
      contextRef="S000033636C000103365"
      decimals="6"
      unitRef="pure">0.00055</rr:ExpensesOverAssets>
    <rr:ExpenseExampleNarrativeTextBlock contextRef="S000033636EMX-I-GUX-I-PRO">
   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:
  </rr:ExpenseExampleNarrativeTextBlock>
    <rr:ExpenseExampleYear01
      contextRef="S000033636C000103365"
      decimals="0"
      unitRef="usd">6</rr:ExpenseExampleYear01>
    <rr:ExpenseExampleYear03
      contextRef="S000033636C000103365"
      decimals="0"
      unitRef="usd">18</rr:ExpenseExampleYear03>
    <rr:ExpenseExampleYear05
      contextRef="S000033636C000103365"
      decimals="0"
      unitRef="usd">31</rr:ExpenseExampleYear05>
    <rr:ExpenseExampleYear10
      contextRef="S000033636C000103365"
      decimals="0"
      unitRef="usd">71</rr:ExpenseExampleYear10>
    <rr:PortfolioTurnoverHeading contextRef="S000033636EMX-I-GUX-I-PRO">
    Portfolio Turnover
   </rr:PortfolioTurnoverHeading>
    <rr:PortfolioTurnoverTextBlock contextRef="S000033636EMX-I-GUX-I-PRO">
    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

      5

    % of the average value of its portfolio.
   </rr:PortfolioTurnoverTextBlock>
    <rr:PortfolioTurnoverRate
      contextRef="S000033636EMX-I-GUX-I-PRO"
      decimals="4"
      unitRef="pure">0.05</rr:PortfolioTurnoverRate>
    <rr:StrategyHeading contextRef="S000033636EMX-I-GUX-I-PRO">
    Principal Investment Strategies
   </rr:StrategyHeading>
    <rr:StrategyNarrativeTextBlock contextRef="S000033636EMX-I-GUX-I-PRO">

     Normally investing at least 80% of assets in securities included in the MSCI ACWI (All Country World Index) ex USA Index and in depositary receipts representing securities included in the index.
     Using statistical sampling techniques based on such factors as capitalization, industry exposures, dividend yield, price/earnings (P/E) ratio, price/book (P/B) ratio, earnings growth, country weightings, and the effect of foreign taxes to attempt to replicate the returns of the MSCI ACWI (All Country World Index) ex USA Index.
     Lending securities to earn income for the fund.


   </rr:StrategyNarrativeTextBlock>
    <rr:RiskHeading contextRef="S000033636EMX-I-GUX-I-PRO">
    Principal Investment Risks
   </rr:RiskHeading>
    <rr:RiskNarrativeTextBlock contextRef="S000033636EMX-I-GUX-I-PRO">

     Stock Market Volatility.


     Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.


     Foreign and Emerging Markets Risk.


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


     The extent of economic development; political stability; market depth, infrastructure, and capitalization; and regulatory oversight can be less than in more developed markets. Emerging markets typically have less established legal, accounting and financial reporting systems than those in more developed markets, which may reduce the scope or quality of financial information available to investors.


     Emerging markets can be subject to greater social, economic, regulatory, and political uncertainties and can be extremely volatile.


     Foreign exchange rates also can be extremely volatile.


     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.


     Changes in the financial condition of an issuer or counterparty (e.g., broker-dealer or other borrower in a securities lending transaction) can increase the risk of default by an issuer or counterparty, which can affect a security's or instrument's value or result in delays in recovering securities and/or capital from a counterparty.


     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.


     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.


     Securities Lending Risk.


     Securities lending involves the risk that the borrower may fail to return the securities loaned in a timely manner or at all. If the borrower defaults on its obligation to return the securities loaned because of insolvency or other reasons, a fund could experience delays and costs in recovering the securities loaned or in gaining access to the collateral.



      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
      .


      &#160;
      You could lose money by investing in the fund.



   </rr:RiskNarrativeTextBlock>
    <rr:RiskNotInsuredDepositoryInstitution contextRef="S000033636EMX-I-GUX-I-PRO">
      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
      .
     </rr:RiskNotInsuredDepositoryInstitution>
    <rr:RiskLoseMoney contextRef="S000033636EMX-I-GUX-I-PRO">
      &#160;
      You could lose money by investing in the fund.
     </rr:RiskLoseMoney>
    <rr:BarChartAndPerformanceTableHeading contextRef="S000033636EMX-I-GUX-I-PRO">
    Performance
   </rr:BarChartAndPerformanceTableHeading>
    <rr:PerformanceNarrativeTextBlock contextRef="S000033636EMX-I-GUX-I-PRO">

     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.


   </rr:PerformanceNarrativeTextBlock>
    <rr:PerformanceInformationIllustratesVariabilityOfReturns contextRef="S000033636EMX-I-GUX-I-PRO">
      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.
     </rr:PerformanceInformationIllustratesVariabilityOfReturns>
    <rr:PerformancePastDoesNotIndicateFuture contextRef="S000033636EMX-I-GUX-I-PRO">
       Past performance (before and after taxes) is not an indication of future performance.
     </rr:PerformancePastDoesNotIndicateFuture>
    <rr:PerformanceAvailabilityWebSiteAddress contextRef="S000033636EMX-I-GUX-I-PRO">
       www.fidelity.com
     </rr:PerformanceAvailabilityWebSiteAddress>
    <rr:BarChartHeading contextRef="S000033636EMX-I-GUX-I-PRO">
    Year-by-Year Returns
   </rr:BarChartHeading>
    <rr:AnnualReturn2012
      contextRef="S000033636C000103365"
      decimals="INF"
      unitRef="pure">0.1779</rr:AnnualReturn2012>
    <rr:AnnualReturn2013
      contextRef="S000033636C000103365"
      decimals="INF"
      unitRef="pure">0.1427</rr:AnnualReturn2013>
    <rr:AnnualReturn2014
      contextRef="S000033636C000103365"
      decimals="INF"
      unitRef="pure">-0.0440</rr:AnnualReturn2014>
    <rr:AnnualReturn2015
      contextRef="S000033636C000103365"
      decimals="INF"
      unitRef="pure">-0.0560</rr:AnnualReturn2015>
    <rr:AnnualReturn2016
      contextRef="S000033636C000103365"
      decimals="INF"
      unitRef="pure">0.0459</rr:AnnualReturn2016>
    <rr:AnnualReturn2017
      contextRef="S000033636C000103365"
      decimals="INF"
      unitRef="pure">0.2740</rr:AnnualReturn2017>
    <rr:AnnualReturn2018
      contextRef="S000033636C000103365"
      decimals="INF"
      unitRef="pure">-0.1391</rr:AnnualReturn2018>
    <rr:AnnualReturn2019
      contextRef="S000033636C000103365"
      decimals="INF"
      unitRef="pure">0.2134</rr:AnnualReturn2019>
    <rr:AnnualReturn2020
      contextRef="S000033636C000103365"
      decimals="INF"
      unitRef="pure">0.1071</rr:AnnualReturn2020>
    <rr:AnnualReturn2021
      contextRef="S000033636C000103365"
      decimals="INF"
      unitRef="pure">0.0776</rr:AnnualReturn2021>
    <rr:HighestQuarterlyReturnLabel contextRef="S000033636EMX-I-GUX-I-PRO">
        &#160;&#160;&#160;Highest Quarter Return
      </rr:HighestQuarterlyReturnLabel>
    <rr:BarChartHighestQuarterlyReturn
      contextRef="S000033636EMX-I-GUX-I-PRO"
      decimals="4"
      unitRef="pure">0.1678</rr:BarChartHighestQuarterlyReturn>
    <rr:BarChartHighestQuarterlyReturnDate contextRef="S000033636EMX-I-GUX-I-PRO">2020-06-30</rr:BarChartHighestQuarterlyReturnDate>
    <rr:LowestQuarterlyReturnLabel contextRef="S000033636EMX-I-GUX-I-PRO">
        &#160;&#160;&#160;Lowest Quarter Return
      </rr:LowestQuarterlyReturnLabel>
    <rr:BarChartLowestQuarterlyReturn
      contextRef="S000033636EMX-I-GUX-I-PRO"
      decimals="4"
      unitRef="pure">-0.2345</rr:BarChartLowestQuarterlyReturn>
    <rr:BarChartLowestQuarterlyReturnDate contextRef="S000033636EMX-I-GUX-I-PRO">2020-03-31</rr:BarChartLowestQuarterlyReturnDate>
    <rr:YearToDateReturnLabel contextRef="S000033636EMX-I-GUX-I-PRO">
        &#160;&#160;&#160;Year-to-Date Return
      </rr:YearToDateReturnLabel>
    <rr:BarChartYearToDateReturn
      contextRef="S000033636EMX-I-GUX-I-PRO"
      decimals="4"
      unitRef="pure">-0.2675</rr:BarChartYearToDateReturn>
    <rr:BarChartYearToDateReturnDate contextRef="S000033636EMX-I-GUX-I-PRO">2022-09-30</rr:BarChartYearToDateReturnDate>
    <rr:PerformanceTableHeading contextRef="S000033636EMX-I-GUX-I-PRO">
    Average Annual Returns
   </rr:PerformanceTableHeading>
    <rr:PerformanceTableNarrativeTextBlock contextRef="S000033636EMX-I-GUX-I-PRO">

     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.

   </rr:PerformanceTableNarrativeTextBlock>
    <rr:PerformanceTableUsesHighestFederalRate contextRef="S000033636EMX-I-GUX-I-PRO">
     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.
    </rr:PerformanceTableUsesHighestFederalRate>
    <rr:PerformanceTableNotRelevantToTaxDeferred contextRef="S000033636EMX-I-GUX-I-PRO">
      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).
    </rr:PerformanceTableNotRelevantToTaxDeferred>
    <rr:PerformanceTableExplanationAfterTaxHigher contextRef="S000033636EMX-I-GUX-I-PRO">
      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.
    </rr:PerformanceTableExplanationAfterTaxHigher>
    <rr:AverageAnnualReturnLabel contextRef="S000033636C000103365ReturnBeforeTaxes">
       Return Before Taxes
      </rr:AverageAnnualReturnLabel>
    <rr:AverageAnnualReturnYear01
      contextRef="S000033636C000103365ReturnBeforeTaxes"
      decimals="4"
      unitRef="pure">0.0776</rr:AverageAnnualReturnYear01>
    <rr:AverageAnnualReturnYear05
      contextRef="S000033636C000103365ReturnBeforeTaxes"
      decimals="4"
      unitRef="pure">0.0969</rr:AverageAnnualReturnYear05>
    <rr:AverageAnnualReturnYear10
      contextRef="S000033636C000103365ReturnBeforeTaxes"
      decimals="4"
      unitRef="pure">0.0727</rr:AverageAnnualReturnYear10>
    <rr:AverageAnnualReturnLabel contextRef="S000033636C000103365AfterTaxesOnDistributions">
       Return After Taxes on Distributions
      </rr:AverageAnnualReturnLabel>
    <rr:AverageAnnualReturnYear01
      contextRef="S000033636C000103365AfterTaxesOnDistributions"
      decimals="4"
      unitRef="pure">0.0718</rr:AverageAnnualReturnYear01>
    <rr:AverageAnnualReturnYear05
      contextRef="S000033636C000103365AfterTaxesOnDistributions"
      decimals="4"
      unitRef="pure">0.0921</rr:AverageAnnualReturnYear05>
    <rr:AverageAnnualReturnYear10
      contextRef="S000033636C000103365AfterTaxesOnDistributions"
      decimals="4"
      unitRef="pure">0.0683</rr:AverageAnnualReturnYear10>
    <rr:AverageAnnualReturnLabel contextRef="S000033636C000103365AfterTaxesOnDistributionsAndSales">
       Return After Taxes on Distributions and Sale of Fund Shares
      </rr:AverageAnnualReturnLabel>
    <rr:AverageAnnualReturnYear01
      contextRef="S000033636C000103365AfterTaxesOnDistributionsAndSales"
      decimals="4"
      unitRef="pure">0.0514</rr:AverageAnnualReturnYear01>
    <rr:AverageAnnualReturnYear05
      contextRef="S000033636C000103365AfterTaxesOnDistributionsAndSales"
      decimals="4"
      unitRef="pure">0.0775</rr:AverageAnnualReturnYear05>
    <rr:AverageAnnualReturnYear10
      contextRef="S000033636C000103365AfterTaxesOnDistributionsAndSales"
      decimals="4"
      unitRef="pure">0.0591</rr:AverageAnnualReturnYear10>
    <rr:AverageAnnualReturnLabel contextRef="S000033636IndexMS112EMX-I-GUX-I-PRO">
       MSCI ACWI (All Country World Index) ex USA Index
      </rr:AverageAnnualReturnLabel>
    <rr:AverageAnnualReturnYear01
      contextRef="S000033636IndexMS112EMX-I-GUX-I-PRO"
      decimals="4"
      unitRef="pure">0.0798</rr:AverageAnnualReturnYear01>
    <rr:AverageAnnualReturnYear05
      contextRef="S000033636IndexMS112EMX-I-GUX-I-PRO"
      decimals="4"
      unitRef="pure">0.0979</rr:AverageAnnualReturnYear05>
    <rr:AverageAnnualReturnYear10
      contextRef="S000033636IndexMS112EMX-I-GUX-I-PRO"
      decimals="4"
      unitRef="pure">0.0744</rr:AverageAnnualReturnYear10>
    <rr:RiskReturnHeading contextRef="S000051996SV7-PRO">
  Fund Summary

   Fund:



    Fidelity&#xae; SAI International Index Fund



 </rr:RiskReturnHeading>
    <rr:ObjectiveHeading contextRef="S000051996SV7-PRO">
  Investment Objective
 </rr:ObjectiveHeading>
    <rr:ObjectivePrimaryTextBlock contextRef="S000051996SV7-PRO">
  Fidelity&#xae; SAI International Index Fund seeks to provide investment results that correspond to the total return of foreign stock markets.
 </rr:ObjectivePrimaryTextBlock>
    <rr:ExpenseHeading contextRef="S000051996SV7-PRO">
  Fee Table
 </rr:ExpenseHeading>
    <rr:ExpenseNarrativeTextBlock contextRef="S000051996SV7-PRO">

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


 </rr:ExpenseNarrativeTextBlock>
    <rr:ShareholderFeesCaption contextRef="S000051996SV7-PRO">
  Shareholder fees
 </rr:ShareholderFeesCaption>
    <rr:ShareholderFeeOther contextRef="S000051996SV7-PRO" decimals="0" unitRef="usd">0</rr:ShareholderFeeOther>
    <rr:OperatingExpensesCaption contextRef="S000051996SV7-PRO">
  Annual Operating Expenses
 </rr:OperatingExpensesCaption>
    <rr:ManagementFeesOverAssets
      contextRef="S000051996C000163542"
      decimals="6"
      unitRef="pure">0.00035</rr:ManagementFeesOverAssets>
    <rr:DistributionAndService12b1FeesOverAssets
      contextRef="S000051996C000163542"
      decimals="6"
      unitRef="pure">0</rr:DistributionAndService12b1FeesOverAssets>
    <rr:OtherExpensesOverAssets
      contextRef="S000051996C000163542"
      decimals="6"
      unitRef="pure">0.00017</rr:OtherExpensesOverAssets>
    <rr:ExpensesOverAssets
      contextRef="S000051996C000163542"
      decimals="6"
      unitRef="pure">0.00052</rr:ExpensesOverAssets>
    <rr:FeeWaiverOrReimbursementOverAssets
      contextRef="S000051996C000163542"
      decimals="6"
      id="footnoteSV7-PROAOE_A_FW"
      unitRef="pure">-0.00017</rr:FeeWaiverOrReimbursementOverAssets>
    <rr:NetExpensesOverAssets
      contextRef="S000051996C000163542"
      decimals="6"
      unitRef="pure">0.00035</rr:NetExpensesOverAssets>
    <rr:FeeWaiverOrReimbursementOverAssetsDateOfTermination contextRef="S000051996SV7-PRO">
   February 29, 2024
  </rr:FeeWaiverOrReimbursementOverAssetsDateOfTermination>
    <rr:ExpenseExampleNarrativeTextBlock contextRef="S000051996SV7-PRO">
  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:
 </rr:ExpenseExampleNarrativeTextBlock>
    <rr:ExpenseExampleYear01
      contextRef="S000051996C000163542"
      decimals="0"
      unitRef="usd">4</rr:ExpenseExampleYear01>
    <rr:ExpenseExampleYear03
      contextRef="S000051996C000163542"
      decimals="0"
      unitRef="usd">14</rr:ExpenseExampleYear03>
    <rr:ExpenseExampleYear05
      contextRef="S000051996C000163542"
      decimals="0"
      unitRef="usd">27</rr:ExpenseExampleYear05>
    <rr:ExpenseExampleYear10
      contextRef="S000051996C000163542"
      decimals="0"
      unitRef="usd">65</rr:ExpenseExampleYear10>
    <rr:PortfolioTurnoverHeading contextRef="S000051996SV7-PRO">
   Portfolio Turnover
  </rr:PortfolioTurnoverHeading>
    <rr:PortfolioTurnoverTextBlock contextRef="S000051996SV7-PRO">
   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

     20

   % of the average value of its portfolio.
  </rr:PortfolioTurnoverTextBlock>
    <rr:PortfolioTurnoverRate contextRef="S000051996SV7-PRO" decimals="4" unitRef="pure">0.20</rr:PortfolioTurnoverRate>
    <rr:StrategyHeading contextRef="S000051996SV7-PRO">
   Principal Investment Strategies
  </rr:StrategyHeading>
    <rr:StrategyNarrativeTextBlock contextRef="S000051996SV7-PRO">

    Normally investing at least 80% of assets in securities included in the MSCI EAFE Index.
    Lending securities to earn income for the fund.
    Using statistical sampling techniques based on such factors as capitalization, industry exposures, dividend yield, price/earnings (P/E) ratio, price/book (P/B) ratio, earnings growth, and country weightings to attempt to replicate the returns of the MSCI EAFE Index.


  </rr:StrategyNarrativeTextBlock>
    <rr:RiskHeading contextRef="S000051996SV7-PRO">
   Principal Investment Risks
  </rr:RiskHeading>
    <rr:RiskNarrativeTextBlock contextRef="S000051996SV7-PRO">

    Stock Market Volatility.


    Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.


    Foreign Exposure.


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


    Foreign exchange rates also can be extremely volatile.


    Geographic Exposure to Japan.


    Because the fund invests a meaningful portion of its assets in Japan, the fund's performance is expected to be closely tied to social, political, and economic conditions within Japan and to be more volatile than the performance of more geographically diversified funds.


    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.


    Changes in the financial condition of an issuer or counterparty (e.g., broker-dealer or other borrower in a securities lending transaction) can increase the risk of default by an issuer or counterparty, which can affect a security's or instrument's value or result in delays in recovering securities and/or capital from a counterparty.


    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.


    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.


    Securities Lending Risk.


    Securities lending involves the risk that the borrower may fail to return the securities loaned in a timely manner or at all. If the borrower defaults on its obligation to return the securities loaned because of insolvency or other reasons, a fund could experience delays and costs in recovering the securities loaned or in gaining access to the collateral.



     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
     .


     &#160;
     You could lose money by investing in the fund.



  </rr:RiskNarrativeTextBlock>
    <rr:RiskNotInsuredDepositoryInstitution contextRef="S000051996SV7-PRO">
     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
     .
    </rr:RiskNotInsuredDepositoryInstitution>
    <rr:RiskLoseMoney contextRef="S000051996SV7-PRO">
     &#160;
     You could lose money by investing in the fund.
    </rr:RiskLoseMoney>
    <rr:BarChartAndPerformanceTableHeading contextRef="S000051996SV7-PRO">
   Performance
  </rr:BarChartAndPerformanceTableHeading>
    <rr:PerformanceNarrativeTextBlock contextRef="S000051996SV7-PRO">

    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.


  </rr:PerformanceNarrativeTextBlock>
    <rr:PerformanceInformationIllustratesVariabilityOfReturns contextRef="S000051996SV7-PRO">
     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.
    </rr:PerformanceInformationIllustratesVariabilityOfReturns>
    <rr:PerformancePastDoesNotIndicateFuture contextRef="S000051996SV7-PRO">
      Past performance (before and after taxes) is not an indication of future performance.
    </rr:PerformancePastDoesNotIndicateFuture>
    <rr:PerformanceAvailabilityWebSiteAddress contextRef="S000051996SV7-PRO">
      www.fidelity.com
    </rr:PerformanceAvailabilityWebSiteAddress>
    <rr:BarChartHeading contextRef="S000051996SV7-PRO">
   Year-by-Year Returns
  </rr:BarChartHeading>
    <rr:AnnualReturn2017
      contextRef="S000051996C000163542"
      decimals="INF"
      unitRef="pure">0.2504</rr:AnnualReturn2017>
    <rr:AnnualReturn2018
      contextRef="S000051996C000163542"
      decimals="INF"
      unitRef="pure">-0.1355</rr:AnnualReturn2018>
    <rr:AnnualReturn2019
      contextRef="S000051996C000163542"
      decimals="INF"
      unitRef="pure">0.2206</rr:AnnualReturn2019>
    <rr:AnnualReturn2020
      contextRef="S000051996C000163542"
      decimals="INF"
      unitRef="pure">0.0816</rr:AnnualReturn2020>
    <rr:AnnualReturn2021
      contextRef="S000051996C000163542"
      decimals="INF"
      unitRef="pure">0.1126</rr:AnnualReturn2021>
    <rr:HighestQuarterlyReturnLabel contextRef="S000051996SV7-PRO">
       &#160;&#160;&#160;Highest Quarter Return
     </rr:HighestQuarterlyReturnLabel>
    <rr:BarChartHighestQuarterlyReturn contextRef="S000051996SV7-PRO" decimals="4" unitRef="pure">0.1587</rr:BarChartHighestQuarterlyReturn>
    <rr:BarChartHighestQuarterlyReturnDate contextRef="S000051996SV7-PRO">2020-12-31</rr:BarChartHighestQuarterlyReturnDate>
    <rr:LowestQuarterlyReturnLabel contextRef="S000051996SV7-PRO">
       &#160;&#160;&#160;Lowest Quarter Return
     </rr:LowestQuarterlyReturnLabel>
    <rr:BarChartLowestQuarterlyReturn contextRef="S000051996SV7-PRO" decimals="4" unitRef="pure">-0.2305</rr:BarChartLowestQuarterlyReturn>
    <rr:BarChartLowestQuarterlyReturnDate contextRef="S000051996SV7-PRO">2020-03-31</rr:BarChartLowestQuarterlyReturnDate>
    <rr:YearToDateReturnLabel contextRef="S000051996SV7-PRO">
       &#160;&#160;&#160;Year-to-Date Return
     </rr:YearToDateReturnLabel>
    <rr:BarChartYearToDateReturn contextRef="S000051996SV7-PRO" decimals="4" unitRef="pure">-0.2756</rr:BarChartYearToDateReturn>
    <rr:BarChartYearToDateReturnDate contextRef="S000051996SV7-PRO">2022-09-30</rr:BarChartYearToDateReturnDate>
    <rr:PerformanceTableHeading contextRef="S000051996SV7-PRO">
   Average Annual Returns
  </rr:PerformanceTableHeading>
    <rr:PerformanceTableNarrativeTextBlock contextRef="S000051996SV7-PRO">

    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.

  </rr:PerformanceTableNarrativeTextBlock>
    <rr:PerformanceTableUsesHighestFederalRate contextRef="S000051996SV7-PRO">
    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.
   </rr:PerformanceTableUsesHighestFederalRate>
    <rr:PerformanceTableNotRelevantToTaxDeferred contextRef="S000051996SV7-PRO">
     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).
   </rr:PerformanceTableNotRelevantToTaxDeferred>
    <rr:PerformanceTableExplanationAfterTaxHigher contextRef="S000051996SV7-PRO">
     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.
   </rr:PerformanceTableExplanationAfterTaxHigher>
    <rr:AverageAnnualReturnLabel contextRef="S000051996C000163542ReturnBeforeTaxes">
      Return Before Taxes
     </rr:AverageAnnualReturnLabel>
    <rr:AverageAnnualReturnYear01
      contextRef="S000051996C000163542ReturnBeforeTaxes"
      decimals="4"
      unitRef="pure">0.1126</rr:AverageAnnualReturnYear01>
    <rr:AverageAnnualReturnYear05
      contextRef="S000051996C000163542ReturnBeforeTaxes"
      decimals="4"
      unitRef="pure">0.0969</rr:AverageAnnualReturnYear05>
    <rr:AverageAnnualReturnSinceInception
      contextRef="S000051996C000163542ReturnBeforeTaxes"
      decimals="4"
      id="footnoteSV7-PROS000051996AAR__RBT"
      unitRef="pure">0.0853</rr:AverageAnnualReturnSinceInception>
    <rr:AverageAnnualReturnLabel contextRef="S000051996C000163542AfterTaxesOnDistributions">
      Return After Taxes on Distributions
     </rr:AverageAnnualReturnLabel>
    <rr:AverageAnnualReturnYear01
      contextRef="S000051996C000163542AfterTaxesOnDistributions"
      decimals="4"
      unitRef="pure">0.1063</rr:AverageAnnualReturnYear01>
    <rr:AverageAnnualReturnYear05
      contextRef="S000051996C000163542AfterTaxesOnDistributions"
      decimals="4"
      unitRef="pure">0.0917</rr:AverageAnnualReturnYear05>
    <rr:AverageAnnualReturnSinceInception
      contextRef="S000051996C000163542AfterTaxesOnDistributions"
      decimals="4"
      id="footnoteSV7-PROS000051996AAR__ATD"
      unitRef="pure">0.0804</rr:AverageAnnualReturnSinceInception>
    <rr:AverageAnnualReturnLabel contextRef="S000051996C000163542AfterTaxesOnDistributionsAndSales">
      Return After Taxes on Distributions and Sale of Fund Shares
     </rr:AverageAnnualReturnLabel>
    <rr:AverageAnnualReturnYear01
      contextRef="S000051996C000163542AfterTaxesOnDistributionsAndSales"
      decimals="4"
      unitRef="pure">0.0722</rr:AverageAnnualReturnYear01>
    <rr:AverageAnnualReturnYear05
      contextRef="S000051996C000163542AfterTaxesOnDistributionsAndSales"
      decimals="4"
      unitRef="pure">0.0773</rr:AverageAnnualReturnYear05>
    <rr:AverageAnnualReturnSinceInception
      contextRef="S000051996C000163542AfterTaxesOnDistributionsAndSales"
      decimals="4"
      id="footnoteSV7-PROS000051996AAR__ATDS"
      unitRef="pure">0.0681</rr:AverageAnnualReturnSinceInception>
    <rr:AverageAnnualReturnLabel contextRef="S000051996IndexMS001SV7-PRO">
      MSCI EAFE Index
     </rr:AverageAnnualReturnLabel>
    <rr:AverageAnnualReturnYear01
      contextRef="S000051996IndexMS001SV7-PRO"
      decimals="4"
      unitRef="pure">0.1148</rr:AverageAnnualReturnYear01>
    <rr:AverageAnnualReturnYear05
      contextRef="S000051996IndexMS001SV7-PRO"
      decimals="4"
      unitRef="pure">0.0978</rr:AverageAnnualReturnYear05>
    <rr:AverageAnnualReturnSinceInception
      contextRef="S000051996IndexMS001SV7-PRO"
      decimals="4"
      id="footnoteSV7-PROS000051996AAR_A_IndexMS001"
      unitRef="pure">0.0884</rr:AverageAnnualReturnSinceInception>
    <rr:AnnualReturnInceptionDate contextRef="S000051996SV7-PRO">2016-01-05</rr:AnnualReturnInceptionDate>
    <rr:RiskReturnHeading contextRef="S000068373EMV-IQI-PRO">
  Fund Summary

   Fund:



    Fidelity&#xae; SAI Emerging Markets Value Index Fund



 </rr:RiskReturnHeading>
    <rr:ObjectiveHeading contextRef="S000068373EMV-IQI-PRO">
  Investment Objective
 </rr:ObjectiveHeading>
    <rr:ObjectivePrimaryTextBlock contextRef="S000068373EMV-IQI-PRO">
  Fidelity&#xae; SAI Emerging Markets Value Index Fund seeks to provide investment results that correspond to the total return of emerging markets stocks with attractive valuations.
 </rr:ObjectivePrimaryTextBlock>
    <rr:ExpenseHeading contextRef="S000068373EMV-IQI-PRO">
  Fee Table
 </rr:ExpenseHeading>
    <rr:ExpenseNarrativeTextBlock contextRef="S000068373EMV-IQI-PRO">

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


 </rr:ExpenseNarrativeTextBlock>
    <rr:ShareholderFeesCaption contextRef="S000068373EMV-IQI-PRO">
  Shareholder fees
 </rr:ShareholderFeesCaption>
    <rr:ShareholderFeeOther
      contextRef="S000068373EMV-IQI-PRO"
      decimals="0"
      unitRef="usd">0</rr:ShareholderFeeOther>
    <rr:OperatingExpensesCaption contextRef="S000068373EMV-IQI-PRO">
  Annual Operating Expenses
 </rr:OperatingExpensesCaption>
    <rr:ManagementFeesOverAssets
      contextRef="S000068373C000218746"
      decimals="6"
      unitRef="pure">0.0015</rr:ManagementFeesOverAssets>
    <rr:DistributionAndService12b1FeesOverAssets
      contextRef="S000068373C000218746"
      decimals="6"
      unitRef="pure">0</rr:DistributionAndService12b1FeesOverAssets>
    <rr:OtherExpensesOverAssets
      contextRef="S000068373C000218746"
      decimals="6"
      unitRef="pure">0.0007</rr:OtherExpensesOverAssets>
    <rr:ExpensesOverAssets
      contextRef="S000068373C000218746"
      decimals="6"
      unitRef="pure">0.0022</rr:ExpensesOverAssets>
    <rr:ExpenseExampleNarrativeTextBlock contextRef="S000068373EMV-IQI-PRO">
  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:
 </rr:ExpenseExampleNarrativeTextBlock>
    <rr:ExpenseExampleYear01
      contextRef="S000068373C000218746"
      decimals="0"
      unitRef="usd">23</rr:ExpenseExampleYear01>
    <rr:ExpenseExampleYear03
      contextRef="S000068373C000218746"
      decimals="0"
      unitRef="usd">71</rr:ExpenseExampleYear03>
    <rr:ExpenseExampleYear05
      contextRef="S000068373C000218746"
      decimals="0"
      unitRef="usd">124</rr:ExpenseExampleYear05>
    <rr:ExpenseExampleYear10
      contextRef="S000068373C000218746"
      decimals="0"
      unitRef="usd">280</rr:ExpenseExampleYear10>
    <rr:PortfolioTurnoverHeading contextRef="S000068373EMV-IQI-PRO">
   Portfolio Turnover
  </rr:PortfolioTurnoverHeading>
    <rr:PortfolioTurnoverTextBlock contextRef="S000068373EMV-IQI-PRO">
   The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was

     30

   % of the average value of its portfolio.
  </rr:PortfolioTurnoverTextBlock>
    <rr:PortfolioTurnoverRate
      contextRef="S000068373EMV-IQI-PRO"
      decimals="4"
      unitRef="pure">0.30</rr:PortfolioTurnoverRate>
    <rr:StrategyHeading contextRef="S000068373EMV-IQI-PRO">
   Principal Investment Strategies
  </rr:StrategyHeading>
    <rr:StrategyNarrativeTextBlock contextRef="S000068373EMV-IQI-PRO">

    Normally investing at least 80% of assets in securities included in the Fidelity Emerging Markets Value Focus IndexSM and in depositary receipts representing securities included in the index. The Fidelity Emerging Markets Value Focus IndexSM is designed to reflect the performance of large and mid-cap stocks in emerging markets that have attractive valuation metrics.
    Using statistical sampling techniques based on such factors as capitalization, industry exposures, dividend yield, price/earnings (P/E) ratio, price/book (P/B) ratio, earnings growth, country weightings, and the effect of foreign taxes to attempt to replicate the returns of the Fidelity Emerging Markets Value Focus Index&#x2120;.
    Lending securities to earn income for the fund.


  </rr:StrategyNarrativeTextBlock>
    <rr:RiskHeading contextRef="S000068373EMV-IQI-PRO">
   Principal Investment Risks
  </rr:RiskHeading>
    <rr:RiskNarrativeTextBlock contextRef="S000068373EMV-IQI-PRO">

    Stock Market Volatility.


    Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.


    Foreign and Emerging Markets Risk.


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


    The extent of economic development; political stability; market depth, infrastructure, and capitalization; and regulatory oversight can be less than in more developed markets. Emerging markets typically have less established legal, accounting and financial reporting systems than those in more developed markets, which may reduce the scope or quality of financial information available to investors.


    Emerging markets can be subject to greater social, economic, regulatory, and political uncertainties and can be extremely volatile.


    Foreign exchange rates also can be extremely volatile.


    Geographic Exposure to China.


    Because the fund invests a meaningful portion of its assets in China, the fund's performance is expected to be closely tied to social, political, and economic conditions in China and to be more volatile than the performance of more geographically diversified funds. The fund may obtain exposure to companies based or operated in China by investing through legal structures known as variable interest entities (VIEs). Instead of directly owning the equity securities of a Chinese company, a VIE enters into service and other contracts with the Chinese company. Although the VIE has no equity ownership of the Chinese company, the contractual arrangements permit the VIE to consolidate the Chinese company into its financial statements. Intervention by the Chinese government with respect to VIEs could significantly affect the Chinese company's performance and the enforceability of the VIE's contractual arrangements with the Chinese company.


    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.


    Changes in the financial condition of an issuer or counterparty (e.g., broker-dealer or other borrower in a securities lending transaction) can increase the risk of default by an issuer or counterparty, which can affect a security's or instrument's value or result in delays in recovering securities and/or capital from a counterparty.


    "Value" Investing.


    "Value" stocks can perform differently from the market as a whole and other types of stocks and can continue to be undervalued by the market for long periods of time.


    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.


    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.


    Securities Lending Risk.


    Securities lending involves the risk that the borrower may fail to return the securities loaned in a timely manner or at all. If the borrower defaults on its obligation to return the securities loaned because of insolvency or other reasons, a fund could experience delays and costs in recovering the securities loaned or in gaining access to the collateral.



     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
     .


     &#160;
     You could lose money by investing in the fund.



  </rr:RiskNarrativeTextBlock>
    <rr:RiskNotInsuredDepositoryInstitution contextRef="S000068373EMV-IQI-PRO">
     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
     .
    </rr:RiskNotInsuredDepositoryInstitution>
    <rr:RiskLoseMoney contextRef="S000068373EMV-IQI-PRO">
     &#160;
     You could lose money by investing in the fund.
    </rr:RiskLoseMoney>
    <rr:BarChartAndPerformanceTableHeading contextRef="S000068373EMV-IQI-PRO">
   Performance
  </rr:BarChartAndPerformanceTableHeading>
    <rr:PerformanceNarrativeTextBlock contextRef="S000068373EMV-IQI-PRO">

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



     The information illustrates the performance of the fund's shares over the past 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.


  </rr:PerformanceNarrativeTextBlock>
    <rr:PerformanceInformationIllustratesVariabilityOfReturns contextRef="S000068373EMV-IQI-PRO">
     The information illustrates the performance of the fund's shares over the past year and compares the performance of the fund's shares to the performance of a securities market index over various periods of time.
    </rr:PerformanceInformationIllustratesVariabilityOfReturns>
    <rr:PerformancePastDoesNotIndicateFuture contextRef="S000068373EMV-IQI-PRO">
     Past performance (before and after taxes) is not an indication of future performance.
    </rr:PerformancePastDoesNotIndicateFuture>
    <rr:PerformanceAvailabilityWebSiteAddress contextRef="S000068373EMV-IQI-PRO">
      www.fidelity.com
    </rr:PerformanceAvailabilityWebSiteAddress>
    <rr:BarChartHeading contextRef="S000068373EMV-IQI-PRO">
   Year-by-Year Returns
  </rr:BarChartHeading>
    <rr:AnnualReturn2021
      contextRef="S000068373C000218746"
      decimals="INF"
      unitRef="pure">0.0603</rr:AnnualReturn2021>
    <rr:HighestQuarterlyReturnLabel contextRef="S000068373EMV-IQI-PRO">
       &#160;&#160;&#160;Highest Quarter Return
     </rr:HighestQuarterlyReturnLabel>
    <rr:BarChartHighestQuarterlyReturn
      contextRef="S000068373EMV-IQI-PRO"
      decimals="4"
      unitRef="pure">0.0663</rr:BarChartHighestQuarterlyReturn>
    <rr:BarChartHighestQuarterlyReturnDate contextRef="S000068373EMV-IQI-PRO">2021-03-31</rr:BarChartHighestQuarterlyReturnDate>
    <rr:LowestQuarterlyReturnLabel contextRef="S000068373EMV-IQI-PRO">
       &#160;&#160;&#160;Lowest Quarter Return
     </rr:LowestQuarterlyReturnLabel>
    <rr:BarChartLowestQuarterlyReturn
      contextRef="S000068373EMV-IQI-PRO"
      decimals="4"
      unitRef="pure">-0.0519</rr:BarChartLowestQuarterlyReturn>
    <rr:BarChartLowestQuarterlyReturnDate contextRef="S000068373EMV-IQI-PRO">2021-09-30</rr:BarChartLowestQuarterlyReturnDate>
    <rr:YearToDateReturnLabel contextRef="S000068373EMV-IQI-PRO">
       &#160;&#160;&#160;Year-to-Date Return
     </rr:YearToDateReturnLabel>
    <rr:BarChartYearToDateReturn
      contextRef="S000068373EMV-IQI-PRO"
      decimals="4"
      unitRef="pure">-0.2518</rr:BarChartYearToDateReturn>
    <rr:BarChartYearToDateReturnDate contextRef="S000068373EMV-IQI-PRO">2022-09-30</rr:BarChartYearToDateReturnDate>
    <rr:PerformanceTableHeading contextRef="S000068373EMV-IQI-PRO">
   Average Annual Returns
  </rr:PerformanceTableHeading>
    <rr:PerformanceTableNarrativeTextBlock contextRef="S000068373EMV-IQI-PRO">

    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.

  </rr:PerformanceTableNarrativeTextBlock>
    <rr:PerformanceTableUsesHighestFederalRate contextRef="S000068373EMV-IQI-PRO">
    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.
   </rr:PerformanceTableUsesHighestFederalRate>
    <rr:PerformanceTableNotRelevantToTaxDeferred contextRef="S000068373EMV-IQI-PRO">
     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).
   </rr:PerformanceTableNotRelevantToTaxDeferred>
    <rr:PerformanceTableExplanationAfterTaxHigher contextRef="S000068373EMV-IQI-PRO">
     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.
   </rr:PerformanceTableExplanationAfterTaxHigher>
    <rr:AverageAnnualReturnLabel contextRef="S000068373C000218746ReturnBeforeTaxes">
      Return Before Taxes
     </rr:AverageAnnualReturnLabel>
    <rr:AverageAnnualReturnYear01
      contextRef="S000068373C000218746ReturnBeforeTaxes"
      decimals="4"
      unitRef="pure">0.0603</rr:AverageAnnualReturnYear01>
    <rr:AverageAnnualReturnSinceInception
      contextRef="S000068373C000218746ReturnBeforeTaxes"
      decimals="4"
      id="footnoteEMV-IQI-PROS000068373AAR__RBT"
      unitRef="pure">0.2597</rr:AverageAnnualReturnSinceInception>
    <rr:AverageAnnualReturnLabel contextRef="S000068373C000218746AfterTaxesOnDistributions">
      Return After Taxes on Distributions
     </rr:AverageAnnualReturnLabel>
    <rr:AverageAnnualReturnYear01
      contextRef="S000068373C000218746AfterTaxesOnDistributions"
      decimals="4"
      unitRef="pure">0.0459</rr:AverageAnnualReturnYear01>
    <rr:AverageAnnualReturnSinceInception
      contextRef="S000068373C000218746AfterTaxesOnDistributions"
      decimals="4"
      id="footnoteEMV-IQI-PROS000068373AAR__ATD"
      unitRef="pure">0.2464</rr:AverageAnnualReturnSinceInception>
    <rr:AverageAnnualReturnLabel contextRef="S000068373C000218746AfterTaxesOnDistributionsAndSales">
      Return After Taxes on Distributions and Sale of Fund Shares
     </rr:AverageAnnualReturnLabel>
    <rr:AverageAnnualReturnYear01
      contextRef="S000068373C000218746AfterTaxesOnDistributionsAndSales"
      decimals="4"
      unitRef="pure">0.0419</rr:AverageAnnualReturnYear01>
    <rr:AverageAnnualReturnSinceInception
      contextRef="S000068373C000218746AfterTaxesOnDistributionsAndSales"
      decimals="4"
      id="footnoteEMV-IQI-PROS000068373AAR__ATDS"
      unitRef="pure">0.1990</rr:AverageAnnualReturnSinceInception>
    <rr:AverageAnnualReturnLabel contextRef="S000068373IndexIXXJHEMV-IQI-PRO">
      Fidelity Emerging Markets Value Focus Index&#x2120;
     </rr:AverageAnnualReturnLabel>
    <rr:AverageAnnualReturnYear01
      contextRef="S000068373IndexIXXJHEMV-IQI-PRO"
      decimals="4"
      unitRef="pure">0.0684</rr:AverageAnnualReturnYear01>
    <rr:AverageAnnualReturnSinceInception
      contextRef="S000068373IndexIXXJHEMV-IQI-PRO"
      decimals="4"
      id="footnoteEMV-IQI-PROS000068373AAR_A_IndexIXXJH"
      unitRef="pure">0.2728</rr:AverageAnnualReturnSinceInception>
    <rr:AnnualReturnInceptionDate contextRef="S000068373EMV-IQI-PRO">2020-05-12</rr:AnnualReturnInceptionDate>
    <rr:RiskReturnHeading contextRef="S000068374EMV-IQI-PRO">
   Fund Summary

    Fund:



     Fidelity&#xae; SAI International Momentum Index Fund



  </rr:RiskReturnHeading>
    <rr:ObjectiveHeading contextRef="S000068374EMV-IQI-PRO">
   Investment Objective
  </rr:ObjectiveHeading>
    <rr:ObjectivePrimaryTextBlock contextRef="S000068374EMV-IQI-PRO">
   Fidelity&#xae; SAI International Momentum Index Fund seeks to provide investment results that correspond to the total return of international stocks with high price momentum.
  </rr:ObjectivePrimaryTextBlock>
    <rr:ExpenseHeading contextRef="S000068374EMV-IQI-PRO">
   Fee Table
  </rr:ExpenseHeading>
    <rr:ExpenseNarrativeTextBlock contextRef="S000068374EMV-IQI-PRO">

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


  </rr:ExpenseNarrativeTextBlock>
    <rr:ShareholderFeesCaption contextRef="S000068374EMV-IQI-PRO">
   Shareholder fees
  </rr:ShareholderFeesCaption>
    <rr:ShareholderFeeOther
      contextRef="S000068374EMV-IQI-PRO"
      decimals="0"
      unitRef="usd">0</rr:ShareholderFeeOther>
    <rr:OperatingExpensesCaption contextRef="S000068374EMV-IQI-PRO">
   Annual Operating Expenses
  </rr:OperatingExpensesCaption>
    <rr:ManagementFeesOverAssets
      contextRef="S000068374C000218747"
      decimals="6"
      unitRef="pure">0.0015</rr:ManagementFeesOverAssets>
    <rr:DistributionAndService12b1FeesOverAssets
      contextRef="S000068374C000218747"
      decimals="6"
      unitRef="pure">0</rr:DistributionAndService12b1FeesOverAssets>
    <rr:OtherExpensesOverAssets
      contextRef="S000068374C000218747"
      decimals="6"
      unitRef="pure">0.0003</rr:OtherExpensesOverAssets>
    <rr:ExpensesOverAssets
      contextRef="S000068374C000218747"
      decimals="6"
      unitRef="pure">0.0018</rr:ExpensesOverAssets>
    <rr:ExpenseExampleNarrativeTextBlock contextRef="S000068374EMV-IQI-PRO">
   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:
  </rr:ExpenseExampleNarrativeTextBlock>
    <rr:ExpenseExampleYear01
      contextRef="S000068374C000218747"
      decimals="0"
      unitRef="usd">18</rr:ExpenseExampleYear01>
    <rr:ExpenseExampleYear03
      contextRef="S000068374C000218747"
      decimals="0"
      unitRef="usd">58</rr:ExpenseExampleYear03>
    <rr:ExpenseExampleYear05
      contextRef="S000068374C000218747"
      decimals="0"
      unitRef="usd">101</rr:ExpenseExampleYear05>
    <rr:ExpenseExampleYear10
      contextRef="S000068374C000218747"
      decimals="0"
      unitRef="usd">230</rr:ExpenseExampleYear10>
    <rr:PortfolioTurnoverHeading contextRef="S000068374EMV-IQI-PRO">
    Portfolio Turnover
   </rr:PortfolioTurnoverHeading>
    <rr:PortfolioTurnoverTextBlock contextRef="S000068374EMV-IQI-PRO">
    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

      113

    % of the average value of its portfolio.
   </rr:PortfolioTurnoverTextBlock>
    <rr:PortfolioTurnoverRate
      contextRef="S000068374EMV-IQI-PRO"
      decimals="4"
      unitRef="pure">1.13</rr:PortfolioTurnoverRate>
    <rr:StrategyHeading contextRef="S000068374EMV-IQI-PRO">
    Principal Investment Strategies
   </rr:StrategyHeading>
    <rr:StrategyNarrativeTextBlock contextRef="S000068374EMV-IQI-PRO">

     Normally investing at least 80% of assets in securities included in the Fidelity International Momentum Focus IndexSM and in depositary receipts representing securities included in the index. The Fidelity International Momentum Focus IndexSM is designed to reflect the performance of large and mid-cap developed international stocks that have attractive momentum characteristics.
     Using statistical sampling techniques based on such factors as capitalization, industry exposures, dividend yield, price/earnings (P/E) ratio, price/book (P/B) ratio, earnings growth, country weightings, and the effect of foreign taxes to attempt to replicate the returns of the Fidelity International Momentum Focus Index&#x2120;.
     Lending securities to earn income for the fund.


   </rr:StrategyNarrativeTextBlock>
    <rr:RiskHeading contextRef="S000068374EMV-IQI-PRO">
    Principal Investment Risks
   </rr:RiskHeading>
    <rr:RiskNarrativeTextBlock contextRef="S000068374EMV-IQI-PRO">

     Stock Market Volatility.


     Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.


     Foreign Exposure.


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


     Foreign exchange rates also can be extremely volatile.


     Geographic Exposure to Japan.


     Because the fund invests a meaningful portion of its assets in Japan, the fund's performance is expected to be closely tied to social, political, and economic conditions within Japan and to be more volatile than the performance of more geographically diversified funds.


     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.


     Changes in the financial condition of an issuer or counterparty (e.g., broker-dealer or other borrower in a securities lending transaction) can increase the risk of default by an issuer or counterparty, which can affect a security's or instrument's value or result in delays in recovering securities and/or capital from a counterparty.


     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.


     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.


     Momentum Securities Risk.


     Although the fund's underlying index uses a rules-based proprietary index methodology that is designed to identify stocks that exhibit positive momentum signals, there is no guarantee that this methodology will be successful. Stocks that previously exhibited high momentum characteristics may not experience positive momentum or may experience more volatility than the market as a whole.


     Securities Lending Risk.


     Securities lending involves the risk that the borrower may fail to return the securities loaned in a timely manner or at all. If the borrower defaults on its obligation to return the securities loaned because of insolvency or other reasons, a fund could experience delays and costs in recovering the securities loaned or in gaining access to the collateral.


     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.



      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
      .


      &#160;
      You could lose money by investing in the fund.



   </rr:RiskNarrativeTextBlock>
    <rr:RiskNotInsuredDepositoryInstitution contextRef="S000068374EMV-IQI-PRO">
      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
      .
     </rr:RiskNotInsuredDepositoryInstitution>
    <rr:RiskLoseMoney contextRef="S000068374EMV-IQI-PRO">
      &#160;
      You could lose money by investing in the fund.
     </rr:RiskLoseMoney>
    <rr:BarChartAndPerformanceTableHeading contextRef="S000068374EMV-IQI-PRO">
    Performance
   </rr:BarChartAndPerformanceTableHeading>
    <rr:PerformanceNarrativeTextBlock contextRef="S000068374EMV-IQI-PRO">

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



      The information illustrates the performance of the fund's shares over the past 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.


   </rr:PerformanceNarrativeTextBlock>
    <rr:PerformanceInformationIllustratesVariabilityOfReturns contextRef="S000068374EMV-IQI-PRO">
      The information illustrates the performance of the fund's shares over the past year and compares the performance of the fund's shares to the performance of a securities market index over various periods of time.
     </rr:PerformanceInformationIllustratesVariabilityOfReturns>
    <rr:PerformancePastDoesNotIndicateFuture contextRef="S000068374EMV-IQI-PRO">
      Past performance (before and after taxes) is not an indication of future performance.
     </rr:PerformancePastDoesNotIndicateFuture>
    <rr:PerformanceAvailabilityWebSiteAddress contextRef="S000068374EMV-IQI-PRO">
       www.fidelity.com
     </rr:PerformanceAvailabilityWebSiteAddress>
    <rr:BarChartHeading contextRef="S000068374EMV-IQI-PRO">
    Year-by-Year Returns
   </rr:BarChartHeading>
    <rr:AnnualReturn2021
      contextRef="S000068374C000218747"
      decimals="INF"
      unitRef="pure">0.1288</rr:AnnualReturn2021>
    <rr:HighestQuarterlyReturnLabel contextRef="S000068374EMV-IQI-PRO">
        &#160;&#160;&#160;Highest Quarter Return
      </rr:HighestQuarterlyReturnLabel>
    <rr:BarChartHighestQuarterlyReturn
      contextRef="S000068374EMV-IQI-PRO"
      decimals="4"
      unitRef="pure">0.0685</rr:BarChartHighestQuarterlyReturn>
    <rr:BarChartHighestQuarterlyReturnDate contextRef="S000068374EMV-IQI-PRO">2021-12-31</rr:BarChartHighestQuarterlyReturnDate>
    <rr:LowestQuarterlyReturnLabel contextRef="S000068374EMV-IQI-PRO">
        &#160;&#160;&#160;Lowest Quarter Return
      </rr:LowestQuarterlyReturnLabel>
    <rr:BarChartLowestQuarterlyReturn
      contextRef="S000068374EMV-IQI-PRO"
      decimals="4"
      unitRef="pure">-0.0031</rr:BarChartLowestQuarterlyReturn>
    <rr:BarChartLowestQuarterlyReturnDate contextRef="S000068374EMV-IQI-PRO">2021-03-31</rr:BarChartLowestQuarterlyReturnDate>
    <rr:YearToDateReturnLabel contextRef="S000068374EMV-IQI-PRO">
        &#160;&#160;&#160;Year-to-Date Return
      </rr:YearToDateReturnLabel>
    <rr:BarChartYearToDateReturn
      contextRef="S000068374EMV-IQI-PRO"
      decimals="4"
      unitRef="pure">-0.3340</rr:BarChartYearToDateReturn>
    <rr:BarChartYearToDateReturnDate contextRef="S000068374EMV-IQI-PRO">2022-09-30</rr:BarChartYearToDateReturnDate>
    <rr:PerformanceTableHeading contextRef="S000068374EMV-IQI-PRO">
    Average Annual Returns
   </rr:PerformanceTableHeading>
    <rr:PerformanceTableNarrativeTextBlock contextRef="S000068374EMV-IQI-PRO">

     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.

   </rr:PerformanceTableNarrativeTextBlock>
    <rr:PerformanceTableUsesHighestFederalRate contextRef="S000068374EMV-IQI-PRO">
     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.
    </rr:PerformanceTableUsesHighestFederalRate>
    <rr:PerformanceTableNotRelevantToTaxDeferred contextRef="S000068374EMV-IQI-PRO">
      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).
    </rr:PerformanceTableNotRelevantToTaxDeferred>
    <rr:PerformanceTableExplanationAfterTaxHigher contextRef="S000068374EMV-IQI-PRO">
      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.
    </rr:PerformanceTableExplanationAfterTaxHigher>
    <rr:AverageAnnualReturnLabel contextRef="S000068374C000218747ReturnBeforeTaxes">
       Return Before Taxes
      </rr:AverageAnnualReturnLabel>
    <rr:AverageAnnualReturnYear01
      contextRef="S000068374C000218747ReturnBeforeTaxes"
      decimals="4"
      unitRef="pure">0.1288</rr:AverageAnnualReturnYear01>
    <rr:AverageAnnualReturnSinceInception
      contextRef="S000068374C000218747ReturnBeforeTaxes"
      decimals="4"
      id="footnoteEMV-IQI-PROS000068374AAR__RBT"
      unitRef="pure">0.2793</rr:AverageAnnualReturnSinceInception>
    <rr:AverageAnnualReturnLabel contextRef="S000068374C000218747AfterTaxesOnDistributions">
       Return After Taxes on Distributions
      </rr:AverageAnnualReturnLabel>
    <rr:AverageAnnualReturnYear01
      contextRef="S000068374C000218747AfterTaxesOnDistributions"
      decimals="4"
      unitRef="pure">0.1223</rr:AverageAnnualReturnYear01>
    <rr:AverageAnnualReturnSinceInception
      contextRef="S000068374C000218747AfterTaxesOnDistributions"
      decimals="4"
      id="footnoteEMV-IQI-PROS000068374AAR__ATD"
      unitRef="pure">0.2722</rr:AverageAnnualReturnSinceInception>
    <rr:AverageAnnualReturnLabel contextRef="S000068374C000218747AfterTaxesOnDistributionsAndSales">
       Return After Taxes on Distributions and Sale of Fund Shares
      </rr:AverageAnnualReturnLabel>
    <rr:AverageAnnualReturnYear01
      contextRef="S000068374C000218747AfterTaxesOnDistributionsAndSales"
      decimals="4"
      unitRef="pure">0.0811</rr:AverageAnnualReturnYear01>
    <rr:AverageAnnualReturnSinceInception
      contextRef="S000068374C000218747AfterTaxesOnDistributionsAndSales"
      decimals="4"
      id="footnoteEMV-IQI-PROS000068374AAR__ATDS"
      unitRef="pure">0.2159</rr:AverageAnnualReturnSinceInception>
    <rr:AverageAnnualReturnLabel contextRef="S000068374IndexIXXJIEMV-IQI-PRO">
       Fidelity International Momentum Focus Index&#x2120;
      </rr:AverageAnnualReturnLabel>
    <rr:AverageAnnualReturnYear01
      contextRef="S000068374IndexIXXJIEMV-IQI-PRO"
      decimals="4"
      unitRef="pure">0.1343</rr:AverageAnnualReturnYear01>
    <rr:AverageAnnualReturnSinceInception
      contextRef="S000068374IndexIXXJIEMV-IQI-PRO"
      decimals="4"
      id="footnoteEMV-IQI-PROS000068374AAR_A_IndexIXXJI"
      unitRef="pure">0.2851</rr:AverageAnnualReturnSinceInception>
    <rr:AnnualReturnInceptionDate contextRef="S000068374EMV-IQI-PRO">2020-05-12</rr:AnnualReturnInceptionDate>
    <rr:RiskReturnHeading contextRef="S000068375EMV-IQI-PRO">
    Fund Summary

     Fund:



      Fidelity&#xae; SAI International Quality Index Fund



   </rr:RiskReturnHeading>
    <rr:ObjectiveHeading contextRef="S000068375EMV-IQI-PRO">
    Investment Objective
   </rr:ObjectiveHeading>
    <rr:ObjectivePrimaryTextBlock contextRef="S000068375EMV-IQI-PRO">
    Fidelity&#xae; SAI International Quality Index Fund seeks to provide investment results that correspond to the total return of stocks of quality growth international companies.
   </rr:ObjectivePrimaryTextBlock>
    <rr:ExpenseHeading contextRef="S000068375EMV-IQI-PRO">
    Fee Table
   </rr:ExpenseHeading>
    <rr:ExpenseNarrativeTextBlock contextRef="S000068375EMV-IQI-PRO">

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


   </rr:ExpenseNarrativeTextBlock>
    <rr:ShareholderFeesCaption contextRef="S000068375EMV-IQI-PRO">
    Shareholder fees
   </rr:ShareholderFeesCaption>
    <rr:ShareholderFeeOther
      contextRef="S000068375EMV-IQI-PRO"
      decimals="0"
      unitRef="usd">0</rr:ShareholderFeeOther>
    <rr:OperatingExpensesCaption contextRef="S000068375EMV-IQI-PRO">
    Annual Operating Expenses
   </rr:OperatingExpensesCaption>
    <rr:ManagementFeesOverAssets
      contextRef="S000068375C000218748"
      decimals="6"
      unitRef="pure">0.0015</rr:ManagementFeesOverAssets>
    <rr:DistributionAndService12b1FeesOverAssets
      contextRef="S000068375C000218748"
      decimals="6"
      unitRef="pure">0</rr:DistributionAndService12b1FeesOverAssets>
    <rr:OtherExpensesOverAssets
      contextRef="S000068375C000218748"
      decimals="6"
      unitRef="pure">0.0004</rr:OtherExpensesOverAssets>
    <rr:ExpensesOverAssets
      contextRef="S000068375C000218748"
      decimals="6"
      unitRef="pure">0.0019</rr:ExpensesOverAssets>
    <rr:ExpenseExampleNarrativeTextBlock contextRef="S000068375EMV-IQI-PRO">
    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:
   </rr:ExpenseExampleNarrativeTextBlock>
    <rr:ExpenseExampleYear01
      contextRef="S000068375C000218748"
      decimals="0"
      unitRef="usd">19</rr:ExpenseExampleYear01>
    <rr:ExpenseExampleYear03
      contextRef="S000068375C000218748"
      decimals="0"
      unitRef="usd">61</rr:ExpenseExampleYear03>
    <rr:ExpenseExampleYear05
      contextRef="S000068375C000218748"
      decimals="0"
      unitRef="usd">107</rr:ExpenseExampleYear05>
    <rr:ExpenseExampleYear10
      contextRef="S000068375C000218748"
      decimals="0"
      unitRef="usd">243</rr:ExpenseExampleYear10>
    <rr:PortfolioTurnoverHeading contextRef="S000068375EMV-IQI-PRO">
     Portfolio Turnover
    </rr:PortfolioTurnoverHeading>
    <rr:PortfolioTurnoverTextBlock contextRef="S000068375EMV-IQI-PRO">
     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

       47

     % of the average value of its portfolio.
    </rr:PortfolioTurnoverTextBlock>
    <rr:PortfolioTurnoverRate
      contextRef="S000068375EMV-IQI-PRO"
      decimals="4"
      unitRef="pure">0.47</rr:PortfolioTurnoverRate>
    <rr:StrategyHeading contextRef="S000068375EMV-IQI-PRO">
     Principal Investment Strategies
    </rr:StrategyHeading>
    <rr:StrategyNarrativeTextBlock contextRef="S000068375EMV-IQI-PRO">

      Normally investing at least 80% of assets in securities included in the Fidelity International Quality Focus IndexSM and in depositary receipts representing securities included in the index. The Fidelity International Quality Focus IndexSM is designed to reflect the performance of large and mid-cap developed international stocks that have attractive quality characteristics.
      Using statistical sampling techniques based on such factors as capitalization, industry exposures, dividend yield, price/earnings (P/E) ratio, price/book (P/B) ratio, earnings growth, country weightings, and the effect of foreign taxes to attempt to replicate the returns of the Fidelity International Quality Focus Index&#x2120;.
      Lending securities to earn income for the fund.


    </rr:StrategyNarrativeTextBlock>
    <rr:RiskHeading contextRef="S000068375EMV-IQI-PRO">
     Principal Investment Risks
    </rr:RiskHeading>
    <rr:RiskNarrativeTextBlock contextRef="S000068375EMV-IQI-PRO">

      Quality Stocks.


      Although the fund's underlying index uses a rules-based proprietary index methodology that is designed to identify stocks with a higher quality profile than the broader market, there is no guarantee that this methodology will be successful or that the past performance of these stocks will continue. Companies that issue these stocks may experience lower than expected returns or may experience negative growth, as well as increased leverage, resulting in lower than expected or negative returns.


      Stock Market Volatility.


      Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.


      Foreign Exposure.


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


      Foreign exchange rates also can be extremely volatile.


      Geographic Exposure to Japan.


      Because the fund invests a meaningful portion of its assets in Japan, the fund's performance is expected to be closely tied to social, political, and economic conditions within Japan and to be more volatile than the performance of more geographically diversified funds.


      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.


      Changes in the financial condition of an issuer or counterparty (e.g., broker-dealer or other borrower in a securities lending transaction) can increase the risk of default by an issuer or counterparty, which can affect a security's or instrument's value or result in delays in recovering securities and/or capital from a counterparty.


      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.


      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.


      Securities Lending Risk.


      Securities lending involves the risk that the borrower may fail to return the securities loaned in a timely manner or at all. If the borrower defaults on its obligation to return the securities loaned because of insolvency or other reasons, a fund could experience delays and costs in recovering the securities loaned or in gaining access to the collateral.



       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
       .


       &#160;
       You could lose money by investing in the fund.



    </rr:RiskNarrativeTextBlock>
    <rr:RiskNotInsuredDepositoryInstitution contextRef="S000068375EMV-IQI-PRO">
       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
       .
      </rr:RiskNotInsuredDepositoryInstitution>
    <rr:RiskLoseMoney contextRef="S000068375EMV-IQI-PRO">
       &#160;
       You could lose money by investing in the fund.
      </rr:RiskLoseMoney>
    <rr:BarChartAndPerformanceTableHeading contextRef="S000068375EMV-IQI-PRO">
     Performance
    </rr:BarChartAndPerformanceTableHeading>
    <rr:PerformanceNarrativeTextBlock contextRef="S000068375EMV-IQI-PRO">

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



       The information illustrates the performance of the fund's shares over the past 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.


    </rr:PerformanceNarrativeTextBlock>
    <rr:PerformanceInformationIllustratesVariabilityOfReturns contextRef="S000068375EMV-IQI-PRO">
       The information illustrates the performance of the fund's shares over the past year and compares the performance of the fund's shares to the performance of a securities market index over various periods of time.
      </rr:PerformanceInformationIllustratesVariabilityOfReturns>
    <rr:PerformancePastDoesNotIndicateFuture contextRef="S000068375EMV-IQI-PRO">
       Past performance (before and after taxes) is not an indication of future performance.
      </rr:PerformancePastDoesNotIndicateFuture>
    <rr:PerformanceAvailabilityWebSiteAddress contextRef="S000068375EMV-IQI-PRO">
        www.fidelity.com
      </rr:PerformanceAvailabilityWebSiteAddress>
    <rr:BarChartHeading contextRef="S000068375EMV-IQI-PRO">
     Year-by-Year Returns
    </rr:BarChartHeading>
    <rr:AnnualReturn2021
      contextRef="S000068375C000218748"
      decimals="INF"
      unitRef="pure">0.1400</rr:AnnualReturn2021>
    <rr:HighestQuarterlyReturnLabel contextRef="S000068375EMV-IQI-PRO">
         &#160;&#160;&#160;Highest Quarter Return
       </rr:HighestQuarterlyReturnLabel>
    <rr:BarChartHighestQuarterlyReturn
      contextRef="S000068375EMV-IQI-PRO"
      decimals="4"
      unitRef="pure">0.0884</rr:BarChartHighestQuarterlyReturn>
    <rr:BarChartHighestQuarterlyReturnDate contextRef="S000068375EMV-IQI-PRO">2021-06-30</rr:BarChartHighestQuarterlyReturnDate>
    <rr:LowestQuarterlyReturnLabel contextRef="S000068375EMV-IQI-PRO">
         &#160;&#160;&#160;Lowest Quarter Return
       </rr:LowestQuarterlyReturnLabel>
    <rr:BarChartLowestQuarterlyReturn
      contextRef="S000068375EMV-IQI-PRO"
      decimals="4"
      unitRef="pure">-0.0054</rr:BarChartLowestQuarterlyReturn>
    <rr:BarChartLowestQuarterlyReturnDate contextRef="S000068375EMV-IQI-PRO">2021-03-31</rr:BarChartLowestQuarterlyReturnDate>
    <rr:YearToDateReturnLabel contextRef="S000068375EMV-IQI-PRO">
         &#160;&#160;&#160;Year-to-Date Return
       </rr:YearToDateReturnLabel>
    <rr:BarChartYearToDateReturn
      contextRef="S000068375EMV-IQI-PRO"
      decimals="4"
      unitRef="pure">-0.2877</rr:BarChartYearToDateReturn>
    <rr:BarChartYearToDateReturnDate contextRef="S000068375EMV-IQI-PRO">2022-09-30</rr:BarChartYearToDateReturnDate>
    <rr:PerformanceTableHeading contextRef="S000068375EMV-IQI-PRO">
     Average Annual Returns
    </rr:PerformanceTableHeading>
    <rr:PerformanceTableNarrativeTextBlock contextRef="S000068375EMV-IQI-PRO">

      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.

    </rr:PerformanceTableNarrativeTextBlock>
    <rr:PerformanceTableUsesHighestFederalRate contextRef="S000068375EMV-IQI-PRO">
      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.
     </rr:PerformanceTableUsesHighestFederalRate>
    <rr:PerformanceTableNotRelevantToTaxDeferred contextRef="S000068375EMV-IQI-PRO">
       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).
     </rr:PerformanceTableNotRelevantToTaxDeferred>
    <rr:PerformanceTableExplanationAfterTaxHigher contextRef="S000068375EMV-IQI-PRO">
       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.
     </rr:PerformanceTableExplanationAfterTaxHigher>
    <rr:AverageAnnualReturnLabel contextRef="S000068375C000218748ReturnBeforeTaxes">
        Return Before Taxes
       </rr:AverageAnnualReturnLabel>
    <rr:AverageAnnualReturnYear01
      contextRef="S000068375C000218748ReturnBeforeTaxes"
      decimals="4"
      unitRef="pure">0.1400</rr:AverageAnnualReturnYear01>
    <rr:AverageAnnualReturnSinceInception
      contextRef="S000068375C000218748ReturnBeforeTaxes"
      decimals="4"
      id="footnoteEMV-IQI-PROS000068375AAR__RBT"
      unitRef="pure">0.2761</rr:AverageAnnualReturnSinceInception>
    <rr:AverageAnnualReturnLabel contextRef="S000068375C000218748AfterTaxesOnDistributions">
        Return After Taxes on Distributions
       </rr:AverageAnnualReturnLabel>
    <rr:AverageAnnualReturnYear01
      contextRef="S000068375C000218748AfterTaxesOnDistributions"
      decimals="4"
      unitRef="pure">0.1017</rr:AverageAnnualReturnYear01>
    <rr:AverageAnnualReturnSinceInception
      contextRef="S000068375C000218748AfterTaxesOnDistributions"
      decimals="4"
      id="footnoteEMV-IQI-PROS000068375AAR__ATD"
      unitRef="pure">0.2480</rr:AverageAnnualReturnSinceInception>
    <rr:AverageAnnualReturnLabel contextRef="S000068375C000218748AfterTaxesOnDistributionsAndSales">
        Return After Taxes on Distributions and Sale of Fund Shares
       </rr:AverageAnnualReturnLabel>
    <rr:AverageAnnualReturnYear01
      contextRef="S000068375C000218748AfterTaxesOnDistributionsAndSales"
      decimals="4"
      unitRef="pure">0.0911</rr:AverageAnnualReturnYear01>
    <rr:AverageAnnualReturnSinceInception
      contextRef="S000068375C000218748AfterTaxesOnDistributionsAndSales"
      decimals="4"
      id="footnoteEMV-IQI-PROS000068375AAR__ATDS"
      unitRef="pure">0.2058</rr:AverageAnnualReturnSinceInception>
    <rr:AverageAnnualReturnLabel contextRef="S000068375IndexIXXJJEMV-IQI-PRO">
        Fidelity International Quality Focus Index&#x2120;
       </rr:AverageAnnualReturnLabel>
    <rr:AverageAnnualReturnYear01
      contextRef="S000068375IndexIXXJJEMV-IQI-PRO"
      decimals="4"
      unitRef="pure">0.1450</rr:AverageAnnualReturnYear01>
    <rr:AverageAnnualReturnSinceInception
      contextRef="S000068375IndexIXXJJEMV-IQI-PRO"
      decimals="4"
      id="footnoteEMV-IQI-PROS000068375AAR_A_IndexIXXJJ"
      unitRef="pure">0.2813</rr:AverageAnnualReturnSinceInception>
    <rr:AnnualReturnInceptionDate contextRef="S000068375EMV-IQI-PRO">2020-05-12</rr:AnnualReturnInceptionDate>
    <rr:RiskReturnHeading contextRef="S000063743SV1-SV2-PRO">
  Fund Summary

   Fund:



    Fidelity&#xae; SAI Emerging Markets Low Volatility Index Fund



 </rr:RiskReturnHeading>
    <rr:ObjectiveHeading contextRef="S000063743SV1-SV2-PRO">
  Investment Objective
 </rr:ObjectiveHeading>
    <rr:ObjectivePrimaryTextBlock contextRef="S000063743SV1-SV2-PRO">
  Fidelity&#xae; SAI Emerging Markets Low Volatility Index Fund seeks to provide investment results that correspond to the total return of low volatility emerging markets stocks.
 </rr:ObjectivePrimaryTextBlock>
    <rr:ExpenseHeading contextRef="S000063743SV1-SV2-PRO">
  Fee Table
 </rr:ExpenseHeading>
    <rr:ExpenseNarrativeTextBlock contextRef="S000063743SV1-SV2-PRO">

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


 </rr:ExpenseNarrativeTextBlock>
    <rr:ShareholderFeesCaption contextRef="S000063743SV1-SV2-PRO">
  Shareholder fees
 </rr:ShareholderFeesCaption>
    <rr:ShareholderFeeOther
      contextRef="S000063743SV1-SV2-PRO"
      decimals="0"
      unitRef="usd">0</rr:ShareholderFeeOther>
    <rr:OperatingExpensesCaption contextRef="S000063743SV1-SV2-PRO">
  Annual Operating Expenses
 </rr:OperatingExpensesCaption>
    <rr:ManagementFeesOverAssets
      contextRef="S000063743C000206607"
      decimals="6"
      unitRef="pure">0.0015</rr:ManagementFeesOverAssets>
    <rr:DistributionAndService12b1FeesOverAssets
      contextRef="S000063743C000206607"
      decimals="6"
      unitRef="pure">0</rr:DistributionAndService12b1FeesOverAssets>
    <rr:OtherExpensesOverAssets
      contextRef="S000063743C000206607"
      decimals="6"
      unitRef="pure">0.0011</rr:OtherExpensesOverAssets>
    <rr:ExpensesOverAssets
      contextRef="S000063743C000206607"
      decimals="6"
      unitRef="pure">0.0026</rr:ExpensesOverAssets>
    <rr:FeeWaiverOrReimbursementOverAssets
      contextRef="S000063743C000206607"
      decimals="6"
      id="footnoteSV1-SV2-PROAOE_A_FW"
      unitRef="pure">-0.0001</rr:FeeWaiverOrReimbursementOverAssets>
    <rr:NetExpensesOverAssets
      contextRef="S000063743C000206607"
      decimals="6"
      unitRef="pure">0.0025</rr:NetExpensesOverAssets>
    <rr:FeeWaiverOrReimbursementOverAssetsDateOfTermination contextRef="S000063743SV1-SV2-PRO">
   February 29, 2024
  </rr:FeeWaiverOrReimbursementOverAssetsDateOfTermination>
    <rr:ExpenseExampleNarrativeTextBlock contextRef="S000063743SV1-SV2-PRO">
  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:
 </rr:ExpenseExampleNarrativeTextBlock>
    <rr:ExpenseExampleYear01
      contextRef="S000063743C000206607"
      decimals="0"
      unitRef="usd">26</rr:ExpenseExampleYear01>
    <rr:ExpenseExampleYear03
      contextRef="S000063743C000206607"
      decimals="0"
      unitRef="usd">82</rr:ExpenseExampleYear03>
    <rr:ExpenseExampleYear05
      contextRef="S000063743C000206607"
      decimals="0"
      unitRef="usd">145</rr:ExpenseExampleYear05>
    <rr:ExpenseExampleYear10
      contextRef="S000063743C000206607"
      decimals="0"
      unitRef="usd">329</rr:ExpenseExampleYear10>
    <rr:PortfolioTurnoverHeading contextRef="S000063743SV1-SV2-PRO">
   Portfolio Turnover
  </rr:PortfolioTurnoverHeading>
    <rr:PortfolioTurnoverTextBlock contextRef="S000063743SV1-SV2-PRO">
   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

     21

   % of the average value of its portfolio.
  </rr:PortfolioTurnoverTextBlock>
    <rr:PortfolioTurnoverRate
      contextRef="S000063743SV1-SV2-PRO"
      decimals="4"
      unitRef="pure">0.21</rr:PortfolioTurnoverRate>
    <rr:StrategyHeading contextRef="S000063743SV1-SV2-PRO">
   Principal Investment Strategies
  </rr:StrategyHeading>
    <rr:StrategyNarrativeTextBlock contextRef="S000063743SV1-SV2-PRO">

    Normally investing at least 80% of assets in securities included in the Fidelity Emerging Markets Low Volatility Focus IndexSM, which reflects the performance of a broad range of emerging markets equities that in the aggregate have lower volatility relative to the broader emerging equity markets.
    Lending securities to earn income for the fund.
    Using statistical sampling techniques based on such factors as capitalization, industry exposures, dividend yield, price/earnings (P/E) ratio, price/book (P/B) ratio, earnings growth, and country weightings to attempt to replicate the returns of the Fidelity Emerging Markets Low Volatility Focus Index&#x2120;.


  </rr:StrategyNarrativeTextBlock>
    <rr:RiskHeading contextRef="S000063743SV1-SV2-PRO">
   Principal Investment Risks
  </rr:RiskHeading>
    <rr:RiskNarrativeTextBlock contextRef="S000063743SV1-SV2-PRO">

    Low Volatility Strategy.


    Although the fund's underlying index uses a rules-based proprietary index methodology that is designed to identify stocks with lower volatility than the broader market, there is no guarantee that this methodology or the fund's low volatility strategy will be successful. There is a risk that the fund may experience more volatility than desired or than the market as a whole. In addition, the securities selected for the index may underperform higher volatility securities.


    Stock Market Volatility.


    Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.


    Foreign and Emerging Markets Risk.


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


    The extent of economic development; political stability; market depth, infrastructure, and capitalization; and regulatory oversight can be less than in more developed markets. Emerging markets typically have less established legal, accounting and financial reporting systems than those in more developed markets, which may reduce the scope or quality of financial information available to investors.


    Emerging markets can be subject to greater social, economic, regulatory, and political uncertainties and can be extremely volatile.


    Foreign exchange rates also can be extremely volatile.


    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.


    Changes in the financial condition of an issuer or counterparty (e.g., broker-dealer or other borrower in a securities lending transaction) can increase the risk of default by an issuer or counterparty, which can affect a security's or instrument's value or result in delays in recovering securities and/or capital from a counterparty.


    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.


    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.


    Securities Lending Risk.


    Securities lending involves the risk that the borrower may fail to return the securities loaned in a timely manner or at all. If the borrower defaults on its obligation to return the securities loaned because of insolvency or other reasons, a fund could experience delays and costs in recovering the securities loaned or in gaining access to the collateral.



     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
     .


     &#160;
     You could lose money by investing in the fund.



  </rr:RiskNarrativeTextBlock>
    <rr:RiskNotInsuredDepositoryInstitution contextRef="S000063743SV1-SV2-PRO">
     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
     .
    </rr:RiskNotInsuredDepositoryInstitution>
    <rr:RiskLoseMoney contextRef="S000063743SV1-SV2-PRO">
     &#160;
     You could lose money by investing in the fund.
    </rr:RiskLoseMoney>
    <rr:BarChartAndPerformanceTableHeading contextRef="S000063743SV1-SV2-PRO">
   Performance
  </rr:BarChartAndPerformanceTableHeading>
    <rr:PerformanceNarrativeTextBlock contextRef="S000063743SV1-SV2-PRO">

    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.


  </rr:PerformanceNarrativeTextBlock>
    <rr:PerformanceInformationIllustratesVariabilityOfReturns contextRef="S000063743SV1-SV2-PRO">
     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.
    </rr:PerformanceInformationIllustratesVariabilityOfReturns>
    <rr:PerformancePastDoesNotIndicateFuture contextRef="S000063743SV1-SV2-PRO">
      Past performance (before and after taxes) is not an indication of future performance.
    </rr:PerformancePastDoesNotIndicateFuture>
    <rr:PerformanceAvailabilityWebSiteAddress contextRef="S000063743SV1-SV2-PRO">
      www.fidelity.com
    </rr:PerformanceAvailabilityWebSiteAddress>
    <rr:BarChartHeading contextRef="S000063743SV1-SV2-PRO">
   Year-by-Year Returns
  </rr:BarChartHeading>
    <rr:AnnualReturn2020
      contextRef="S000063743C000206607"
      decimals="INF"
      unitRef="pure">0.0521</rr:AnnualReturn2020>
    <rr:AnnualReturn2021
      contextRef="S000063743C000206607"
      decimals="INF"
      unitRef="pure">0.1077</rr:AnnualReturn2021>
    <rr:HighestQuarterlyReturnLabel contextRef="S000063743SV1-SV2-PRO">
       &#160;&#160;&#160;Highest Quarter Return
     </rr:HighestQuarterlyReturnLabel>
    <rr:BarChartHighestQuarterlyReturn
      contextRef="S000063743SV1-SV2-PRO"
      decimals="4"
      unitRef="pure">0.1503</rr:BarChartHighestQuarterlyReturn>
    <rr:BarChartHighestQuarterlyReturnDate contextRef="S000063743SV1-SV2-PRO">2020-06-30</rr:BarChartHighestQuarterlyReturnDate>
    <rr:LowestQuarterlyReturnLabel contextRef="S000063743SV1-SV2-PRO">
       &#160;&#160;&#160;Lowest Quarter Return
     </rr:LowestQuarterlyReturnLabel>
    <rr:BarChartLowestQuarterlyReturn
      contextRef="S000063743SV1-SV2-PRO"
      decimals="4"
      unitRef="pure">-0.2334</rr:BarChartLowestQuarterlyReturn>
    <rr:BarChartLowestQuarterlyReturnDate contextRef="S000063743SV1-SV2-PRO">2020-03-31</rr:BarChartLowestQuarterlyReturnDate>
    <rr:YearToDateReturnLabel contextRef="S000063743SV1-SV2-PRO">
       &#160;&#160;&#160;Year-to-Date Return
     </rr:YearToDateReturnLabel>
    <rr:BarChartYearToDateReturn
      contextRef="S000063743SV1-SV2-PRO"
      decimals="4"
      unitRef="pure">-0.1755</rr:BarChartYearToDateReturn>
    <rr:BarChartYearToDateReturnDate contextRef="S000063743SV1-SV2-PRO">2022-09-30</rr:BarChartYearToDateReturnDate>
    <rr:PerformanceTableHeading contextRef="S000063743SV1-SV2-PRO">
   Average Annual Returns
  </rr:PerformanceTableHeading>
    <rr:PerformanceTableNarrativeTextBlock contextRef="S000063743SV1-SV2-PRO">

    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.

  </rr:PerformanceTableNarrativeTextBlock>
    <rr:PerformanceTableUsesHighestFederalRate contextRef="S000063743SV1-SV2-PRO">
    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.
   </rr:PerformanceTableUsesHighestFederalRate>
    <rr:PerformanceTableNotRelevantToTaxDeferred contextRef="S000063743SV1-SV2-PRO">
     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).
   </rr:PerformanceTableNotRelevantToTaxDeferred>
    <rr:PerformanceTableExplanationAfterTaxHigher contextRef="S000063743SV1-SV2-PRO">
     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.
   </rr:PerformanceTableExplanationAfterTaxHigher>
    <rr:AverageAnnualReturnLabel contextRef="S000063743C000206607ReturnBeforeTaxes">
      Return Before Taxes
     </rr:AverageAnnualReturnLabel>
    <rr:AverageAnnualReturnYear01
      contextRef="S000063743C000206607ReturnBeforeTaxes"
      decimals="4"
      unitRef="pure">0.1077</rr:AverageAnnualReturnYear01>
    <rr:AverageAnnualReturnSinceInception
      contextRef="S000063743C000206607ReturnBeforeTaxes"
      decimals="4"
      id="footnoteSV1-SV2-PROS000063743AAR__RBT"
      unitRef="pure">0.0695</rr:AverageAnnualReturnSinceInception>
    <rr:AverageAnnualReturnLabel contextRef="S000063743C000206607AfterTaxesOnDistributions">
      Return After Taxes on Distributions
     </rr:AverageAnnualReturnLabel>
    <rr:AverageAnnualReturnYear01
      contextRef="S000063743C000206607AfterTaxesOnDistributions"
      decimals="4"
      unitRef="pure">0.1025</rr:AverageAnnualReturnYear01>
    <rr:AverageAnnualReturnSinceInception
      contextRef="S000063743C000206607AfterTaxesOnDistributions"
      decimals="4"
      id="footnoteSV1-SV2-PROS000063743AAR__ATD"
      unitRef="pure">0.0645</rr:AverageAnnualReturnSinceInception>
    <rr:AverageAnnualReturnLabel contextRef="S000063743C000206607AfterTaxesOnDistributionsAndSales">
      Return After Taxes on Distributions and Sale of Fund Shares
     </rr:AverageAnnualReturnLabel>
    <rr:AverageAnnualReturnYear01
      contextRef="S000063743C000206607AfterTaxesOnDistributionsAndSales"
      decimals="4"
      unitRef="pure">0.0687</rr:AverageAnnualReturnYear01>
    <rr:AverageAnnualReturnSinceInception
      contextRef="S000063743C000206607AfterTaxesOnDistributionsAndSales"
      decimals="4"
      id="footnoteSV1-SV2-PROS000063743AAR__ATDS"
      unitRef="pure">0.0535</rr:AverageAnnualReturnSinceInception>
    <rr:AverageAnnualReturnLabel contextRef="S000063743IndexIXYQLSV1-SV2-PRO">
      Fidelity Emerging Markets Low Volatility Focus Index&#x2120;
     </rr:AverageAnnualReturnLabel>
    <rr:AverageAnnualReturnYear01
      contextRef="S000063743IndexIXYQLSV1-SV2-PRO"
      decimals="4"
      unitRef="pure">0.1204</rr:AverageAnnualReturnYear01>
    <rr:AverageAnnualReturnSinceInception
      contextRef="S000063743IndexIXYQLSV1-SV2-PRO"
      decimals="4"
      id="footnoteSV1-SV2-PROS000063743AAR_A_IndexIXYQL"
      unitRef="pure">0.0833</rr:AverageAnnualReturnSinceInception>
    <rr:AnnualReturnInceptionDate contextRef="S000063743SV1-SV2-PRO">2019-01-30</rr:AnnualReturnInceptionDate>
    <rr:RiskReturnHeading contextRef="S000049310SV1-SV2-PRO">
   Fund Summary

    Fund:



     Fidelity&#xae; SAI International Low Volatility Index Fund



  </rr:RiskReturnHeading>
    <rr:ObjectiveHeading contextRef="S000049310SV1-SV2-PRO">
   Investment Objective
  </rr:ObjectiveHeading>
    <rr:ObjectivePrimaryTextBlock contextRef="S000049310SV1-SV2-PRO">
   Fidelity&#xae; SAI International Low Volatility Index Fund seeks to provide investment results that correspond to the total return of low volatility foreign stocks.
  </rr:ObjectivePrimaryTextBlock>
    <rr:ExpenseHeading contextRef="S000049310SV1-SV2-PRO">
   Fee Table
  </rr:ExpenseHeading>
    <rr:ExpenseNarrativeTextBlock contextRef="S000049310SV1-SV2-PRO">

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


  </rr:ExpenseNarrativeTextBlock>
    <rr:ShareholderFeesCaption contextRef="S000049310SV1-SV2-PRO">
   Shareholder fees
  </rr:ShareholderFeesCaption>
    <rr:ShareholderFeeOther
      contextRef="S000049310SV1-SV2-PRO"
      decimals="0"
      unitRef="usd">0</rr:ShareholderFeeOther>
    <rr:OperatingExpensesCaption contextRef="S000049310SV1-SV2-PRO">
   Annual Operating Expenses
  </rr:OperatingExpensesCaption>
    <rr:ManagementFeesOverAssets
      contextRef="S000049310C000155835"
      decimals="6"
      unitRef="pure">0.0015</rr:ManagementFeesOverAssets>
    <rr:DistributionAndService12b1FeesOverAssets
      contextRef="S000049310C000155835"
      decimals="6"
      unitRef="pure">0</rr:DistributionAndService12b1FeesOverAssets>
    <rr:OtherExpensesOverAssets
      contextRef="S000049310C000155835"
      decimals="6"
      unitRef="pure">0.0002</rr:OtherExpensesOverAssets>
    <rr:ExpensesOverAssets
      contextRef="S000049310C000155835"
      decimals="6"
      unitRef="pure">0.0017</rr:ExpensesOverAssets>
    <rr:ExpenseExampleNarrativeTextBlock contextRef="S000049310SV1-SV2-PRO">
   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:
  </rr:ExpenseExampleNarrativeTextBlock>
    <rr:ExpenseExampleYear01
      contextRef="S000049310C000155835"
      decimals="0"
      unitRef="usd">17</rr:ExpenseExampleYear01>
    <rr:ExpenseExampleYear03
      contextRef="S000049310C000155835"
      decimals="0"
      unitRef="usd">55</rr:ExpenseExampleYear03>
    <rr:ExpenseExampleYear05
      contextRef="S000049310C000155835"
      decimals="0"
      unitRef="usd">96</rr:ExpenseExampleYear05>
    <rr:ExpenseExampleYear10
      contextRef="S000049310C000155835"
      decimals="0"
      unitRef="usd">217</rr:ExpenseExampleYear10>
    <rr:PortfolioTurnoverHeading contextRef="S000049310SV1-SV2-PRO">
    Portfolio Turnover
   </rr:PortfolioTurnoverHeading>
    <rr:PortfolioTurnoverTextBlock contextRef="S000049310SV1-SV2-PRO">
    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

      26

    % of the average value of its portfolio.
   </rr:PortfolioTurnoverTextBlock>
    <rr:PortfolioTurnoverRate
      contextRef="S000049310SV1-SV2-PRO"
      decimals="4"
      unitRef="pure">0.26</rr:PortfolioTurnoverRate>
    <rr:StrategyHeading contextRef="S000049310SV1-SV2-PRO">
    Principal Investment Strategies
   </rr:StrategyHeading>
    <rr:StrategyNarrativeTextBlock contextRef="S000049310SV1-SV2-PRO">

     Normally investing at least 80% of assets in equity securities included in the Fidelity International Low Volatility Focus IndexSM, which reflects the performance of a broad range of equities across developed markets that in the aggregate have lower volatility relative to the broader foreign developed equity markets.
     Lending securities to earn income for the fund.


   </rr:StrategyNarrativeTextBlock>
    <rr:RiskHeading contextRef="S000049310SV1-SV2-PRO">
    Principal Investment Risks
   </rr:RiskHeading>
    <rr:RiskNarrativeTextBlock contextRef="S000049310SV1-SV2-PRO">

     Low Volatility Strategy.


     Although the fund's underlying index uses a rules-based proprietary index methodology that is designed to identify stocks with lower volatility than the broader market, there is no guarantee that this methodology or the fund's low volatility strategy will be successful. There is a risk that the fund may experience more volatility than desired or than the market as a whole. In addition, the securities selected for the index may underperform higher volatility securities.


     Stock Market Volatility.


     Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.


     Foreign and Emerging Markets Risk.


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


     The extent of economic development; political stability; market depth, infrastructure, and capitalization; and regulatory oversight can be less than in more developed markets. Emerging markets typically have less established legal, accounting and financial reporting systems than those in more developed markets, which may reduce the scope or quality of financial information available to investors.


     Emerging markets can be subject to greater social, economic, regulatory, and political uncertainties and can be extremely volatile.


     Foreign exchange rates also can be extremely volatile.


     Geographic Exposure to Japan.


     Because the fund invests a meaningful portion of its assets in Japan, the fund's performance is expected to be closely tied to social, political, and economic conditions within Japan and to be more volatile than the performance of more geographically diversified funds.


     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.


     Changes in the financial condition of an issuer or counterparty (e.g., broker-dealer or other borrower in a securities lending transaction) can increase the risk of default by an issuer or counterparty, which can affect a security's or instrument's value or result in delays in recovering securities and/or capital from a counterparty.


     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.


     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.


     Securities Lending Risk.


     Securities lending involves the risk that the borrower may fail to return the securities loaned in a timely manner or at all. If the borrower defaults on its obligation to return the securities loaned because of insolvency or other reasons, a fund could experience delays and costs in recovering the securities loaned or in gaining access to the collateral.



      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
      .


      &#160;
      You could lose money by investing in the fund.



   </rr:RiskNarrativeTextBlock>
    <rr:RiskNotInsuredDepositoryInstitution contextRef="S000049310SV1-SV2-PRO">
      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
      .
     </rr:RiskNotInsuredDepositoryInstitution>
    <rr:RiskLoseMoney contextRef="S000049310SV1-SV2-PRO">
      &#160;
      You could lose money by investing in the fund.
     </rr:RiskLoseMoney>
    <rr:BarChartAndPerformanceTableHeading contextRef="S000049310SV1-SV2-PRO">
    Performance
   </rr:BarChartAndPerformanceTableHeading>
    <rr:PerformanceNarrativeTextBlock contextRef="S000049310SV1-SV2-PRO">

     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 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.



     Prior to February 18, 2019, the fund was named Fidelity&#xae; SAI International Minimum Volatility Index Fund and the fund operated under certain different investment policies and compared its performance to a different index. The fund's historical performance may not represent its current investment policies.


     Visit

       www.fidelity.com

     for more recent performance information.


   </rr:PerformanceNarrativeTextBlock>
    <rr:PerformanceInformationIllustratesVariabilityOfReturns contextRef="S000049310SV1-SV2-PRO">
      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.
     </rr:PerformanceInformationIllustratesVariabilityOfReturns>
    <rr:PerformancePastDoesNotIndicateFuture contextRef="S000049310SV1-SV2-PRO">
       Past performance (before and after taxes) is not an indication of future performance.
     </rr:PerformancePastDoesNotIndicateFuture>
    <rr:PerformanceAvailabilityWebSiteAddress contextRef="S000049310SV1-SV2-PRO">
       www.fidelity.com
     </rr:PerformanceAvailabilityWebSiteAddress>
    <rr:BarChartHeading contextRef="S000049310SV1-SV2-PRO">
    Year-by-Year Returns
   </rr:BarChartHeading>
    <rr:AnnualReturn2016
      contextRef="S000049310C000155835"
      decimals="INF"
      unitRef="pure">0.0243</rr:AnnualReturn2016>
    <rr:AnnualReturn2017
      contextRef="S000049310C000155835"
      decimals="INF"
      unitRef="pure">0.2140</rr:AnnualReturn2017>
    <rr:AnnualReturn2018
      contextRef="S000049310C000155835"
      decimals="INF"
      unitRef="pure">-0.0486</rr:AnnualReturn2018>
    <rr:AnnualReturn2019
      contextRef="S000049310C000155835"
      decimals="INF"
      unitRef="pure">0.1608</rr:AnnualReturn2019>
    <rr:AnnualReturn2020
      contextRef="S000049310C000155835"
      decimals="INF"
      unitRef="pure">-0.0157</rr:AnnualReturn2020>
    <rr:AnnualReturn2021
      contextRef="S000049310C000155835"
      decimals="INF"
      unitRef="pure">0.0990</rr:AnnualReturn2021>
    <rr:HighestQuarterlyReturnLabel contextRef="S000049310SV1-SV2-PRO">
        &#160;&#160;&#160;Highest Quarter Return
      </rr:HighestQuarterlyReturnLabel>
    <rr:BarChartHighestQuarterlyReturn
      contextRef="S000049310SV1-SV2-PRO"
      decimals="4"
      unitRef="pure">0.0825</rr:BarChartHighestQuarterlyReturn>
    <rr:BarChartHighestQuarterlyReturnDate contextRef="S000049310SV1-SV2-PRO">2020-12-31</rr:BarChartHighestQuarterlyReturnDate>
    <rr:LowestQuarterlyReturnLabel contextRef="S000049310SV1-SV2-PRO">
        &#160;&#160;&#160;Lowest Quarter Return
      </rr:LowestQuarterlyReturnLabel>
    <rr:BarChartLowestQuarterlyReturn
      contextRef="S000049310SV1-SV2-PRO"
      decimals="4"
      unitRef="pure">-0.1734</rr:BarChartLowestQuarterlyReturn>
    <rr:BarChartLowestQuarterlyReturnDate contextRef="S000049310SV1-SV2-PRO">2020-03-31</rr:BarChartLowestQuarterlyReturnDate>
    <rr:YearToDateReturnLabel contextRef="S000049310SV1-SV2-PRO">
        &#160;&#160;&#160;Year-to-Date Return
      </rr:YearToDateReturnLabel>
    <rr:BarChartYearToDateReturn
      contextRef="S000049310SV1-SV2-PRO"
      decimals="4"
      unitRef="pure">-0.2209</rr:BarChartYearToDateReturn>
    <rr:BarChartYearToDateReturnDate contextRef="S000049310SV1-SV2-PRO">2022-09-30</rr:BarChartYearToDateReturnDate>
    <rr:PerformanceTableHeading contextRef="S000049310SV1-SV2-PRO">
    Average Annual Returns
   </rr:PerformanceTableHeading>
    <rr:PerformanceTableNarrativeTextBlock contextRef="S000049310SV1-SV2-PRO">

     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.

   </rr:PerformanceTableNarrativeTextBlock>
    <rr:PerformanceTableUsesHighestFederalRate contextRef="S000049310SV1-SV2-PRO">
     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.
    </rr:PerformanceTableUsesHighestFederalRate>
    <rr:PerformanceTableNotRelevantToTaxDeferred contextRef="S000049310SV1-SV2-PRO">
      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).
    </rr:PerformanceTableNotRelevantToTaxDeferred>
    <rr:PerformanceTableExplanationAfterTaxHigher contextRef="S000049310SV1-SV2-PRO">
      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.
    </rr:PerformanceTableExplanationAfterTaxHigher>
    <rr:AverageAnnualReturnLabel contextRef="S000049310C000155835ReturnBeforeTaxes">
       Return Before Taxes
      </rr:AverageAnnualReturnLabel>
    <rr:AverageAnnualReturnYear01
      contextRef="S000049310C000155835ReturnBeforeTaxes"
      decimals="4"
      unitRef="pure">0.0990</rr:AverageAnnualReturnYear01>
    <rr:AverageAnnualReturnYear05
      contextRef="S000049310C000155835ReturnBeforeTaxes"
      decimals="4"
      unitRef="pure">0.0772</rr:AverageAnnualReturnYear05>
    <rr:AverageAnnualReturnSinceInception
      contextRef="S000049310C000155835ReturnBeforeTaxes"
      decimals="4"
      id="footnoteSV1-SV2-PROS000049310AAR__RBT"
      unitRef="pure">0.0512</rr:AverageAnnualReturnSinceInception>
    <rr:AverageAnnualReturnLabel contextRef="S000049310C000155835AfterTaxesOnDistributions">
       Return After Taxes on Distributions
      </rr:AverageAnnualReturnLabel>
    <rr:AverageAnnualReturnYear01
      contextRef="S000049310C000155835AfterTaxesOnDistributions"
      decimals="4"
      unitRef="pure">0.0938</rr:AverageAnnualReturnYear01>
    <rr:AverageAnnualReturnYear05
      contextRef="S000049310C000155835AfterTaxesOnDistributions"
      decimals="4"
      unitRef="pure">0.0710</rr:AverageAnnualReturnYear05>
    <rr:AverageAnnualReturnSinceInception
      contextRef="S000049310C000155835AfterTaxesOnDistributions"
      decimals="4"
      id="footnoteSV1-SV2-PROS000049310AAR__ATD"
      unitRef="pure">0.0450</rr:AverageAnnualReturnSinceInception>
    <rr:AverageAnnualReturnLabel contextRef="S000049310C000155835AfterTaxesOnDistributionsAndSales">
       Return After Taxes on Distributions and Sale of Fund Shares
      </rr:AverageAnnualReturnLabel>
    <rr:AverageAnnualReturnYear01
      contextRef="S000049310C000155835AfterTaxesOnDistributionsAndSales"
      decimals="4"
      unitRef="pure">0.0640</rr:AverageAnnualReturnYear01>
    <rr:AverageAnnualReturnYear05
      contextRef="S000049310C000155835AfterTaxesOnDistributionsAndSales"
      decimals="4"
      unitRef="pure">0.0610</rr:AverageAnnualReturnYear05>
    <rr:AverageAnnualReturnSinceInception
      contextRef="S000049310C000155835AfterTaxesOnDistributionsAndSales"
      decimals="4"
      id="footnoteSV1-SV2-PROS000049310AAR__ATDS"
      unitRef="pure">0.0399</rr:AverageAnnualReturnSinceInception>
    <rr:AverageAnnualReturnLabel contextRef="S000049310IndexIXYQQSV1-SV2-PRO">
       Fidelity International Low Volatility Focus Index&#x2120;
      </rr:AverageAnnualReturnLabel>
    <rr:AverageAnnualReturnYear01
      contextRef="S000049310IndexIXYQQSV1-SV2-PRO"
      decimals="4"
      unitRef="pure">0.1014</rr:AverageAnnualReturnYear01>
    <rr:AverageAnnualReturnLabel contextRef="S000049310IndexIXYXOSV1-SV2-PRO">
       Fidelity SAI International Low Volatility Index Fund Linked Index&#x2120;
      </rr:AverageAnnualReturnLabel>
    <rr:AverageAnnualReturnYear01
      contextRef="S000049310IndexIXYXOSV1-SV2-PRO"
      decimals="4"
      unitRef="pure">0.1014</rr:AverageAnnualReturnYear01>
    <rr:AverageAnnualReturnYear05
      contextRef="S000049310IndexIXYXOSV1-SV2-PRO"
      decimals="4"
      unitRef="pure">0.0800</rr:AverageAnnualReturnYear05>
    <rr:AverageAnnualReturnSinceInception
      contextRef="S000049310IndexIXYXOSV1-SV2-PRO"
      decimals="4"
      id="footnoteSV1-SV2-PROS000049310AAR_A_IndexIXYXO"
      unitRef="pure">0.0543</rr:AverageAnnualReturnSinceInception>
    <rr:AnnualReturnInceptionDate contextRef="S000049310SV1-SV2-PRO">2015-05-29</rr:AnnualReturnInceptionDate>
    <rr:RiskReturnHeading contextRef="S000049309SV1-SV2-PRO">
    Fund Summary

     Fund:



      Fidelity&#xae; SAI U.S. Low Volatility Index Fund



   </rr:RiskReturnHeading>
    <rr:ObjectiveHeading contextRef="S000049309SV1-SV2-PRO">
    Investment Objective
   </rr:ObjectiveHeading>
    <rr:ObjectivePrimaryTextBlock contextRef="S000049309SV1-SV2-PRO">
    Fidelity&#xae; SAI U.S. Low Volatility Index Fund seeks to provide investment results that correspond to the total return of low volatility U.S. stocks.
   </rr:ObjectivePrimaryTextBlock>
    <rr:ExpenseHeading contextRef="S000049309SV1-SV2-PRO">
    Fee Table
   </rr:ExpenseHeading>
    <rr:ExpenseNarrativeTextBlock contextRef="S000049309SV1-SV2-PRO">

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


   </rr:ExpenseNarrativeTextBlock>
    <rr:ShareholderFeesCaption contextRef="S000049309SV1-SV2-PRO">
    Shareholder fees
   </rr:ShareholderFeesCaption>
    <rr:ShareholderFeeOther
      contextRef="S000049309SV1-SV2-PRO"
      decimals="0"
      unitRef="usd">0</rr:ShareholderFeeOther>
    <rr:OperatingExpensesCaption contextRef="S000049309SV1-SV2-PRO">
    Annual Operating Expenses
   </rr:OperatingExpensesCaption>
    <rr:ManagementFeesOverAssets
      contextRef="S000049309C000155834"
      decimals="6"
      unitRef="pure">0.0010</rr:ManagementFeesOverAssets>
    <rr:DistributionAndService12b1FeesOverAssets
      contextRef="S000049309C000155834"
      decimals="6"
      unitRef="pure">0</rr:DistributionAndService12b1FeesOverAssets>
    <rr:OtherExpensesOverAssets
      contextRef="S000049309C000155834"
      decimals="6"
      unitRef="pure">0.0001</rr:OtherExpensesOverAssets>
    <rr:ExpensesOverAssets
      contextRef="S000049309C000155834"
      decimals="6"
      unitRef="pure">0.0011</rr:ExpensesOverAssets>
    <rr:ExpenseExampleNarrativeTextBlock contextRef="S000049309SV1-SV2-PRO">
    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:
   </rr:ExpenseExampleNarrativeTextBlock>
    <rr:ExpenseExampleYear01
      contextRef="S000049309C000155834"
      decimals="0"
      unitRef="usd">11</rr:ExpenseExampleYear01>
    <rr:ExpenseExampleYear03
      contextRef="S000049309C000155834"
      decimals="0"
      unitRef="usd">35</rr:ExpenseExampleYear03>
    <rr:ExpenseExampleYear05
      contextRef="S000049309C000155834"
      decimals="0"
      unitRef="usd">62</rr:ExpenseExampleYear05>
    <rr:ExpenseExampleYear10
      contextRef="S000049309C000155834"
      decimals="0"
      unitRef="usd">141</rr:ExpenseExampleYear10>
    <rr:PortfolioTurnoverHeading contextRef="S000049309SV1-SV2-PRO">
     Portfolio Turnover
    </rr:PortfolioTurnoverHeading>
    <rr:PortfolioTurnoverTextBlock contextRef="S000049309SV1-SV2-PRO">
     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

       41

     % of the average value of its portfolio.
    </rr:PortfolioTurnoverTextBlock>
    <rr:PortfolioTurnoverRate
      contextRef="S000049309SV1-SV2-PRO"
      decimals="4"
      unitRef="pure">0.41</rr:PortfolioTurnoverRate>
    <rr:StrategyHeading contextRef="S000049309SV1-SV2-PRO">
     Principal Investment Strategies
    </rr:StrategyHeading>
    <rr:StrategyNarrativeTextBlock contextRef="S000049309SV1-SV2-PRO">

      Normally investing at least 80% of assets in U.S. equity securities included in the Fidelity U.S. Low Volatility Focus IndexSM, which represents the performance of a broad range of U.S. equities that in the aggregate have lower volatility relative to the broader U.S. equity market.
      Lending securities to earn income for the fund.


    </rr:StrategyNarrativeTextBlock>
    <rr:RiskHeading contextRef="S000049309SV1-SV2-PRO">
     Principal Investment Risks
    </rr:RiskHeading>
    <rr:RiskNarrativeTextBlock contextRef="S000049309SV1-SV2-PRO">

      Low Volatility Strategy.


      Although the fund's underlying index uses a rules-based proprietary index methodology that is designed to identify stocks with lower volatility than the broader market, there is no guarantee that this methodology or the fund's low volatility strategy will be successful. There is a risk that the fund may experience more volatility than desired or than the market as a whole. In addition, the securities selected for the index may underperform higher volatility securities.


      Stock Market Volatility.


      Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.


      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.


      Changes in the financial condition of an issuer or counterparty (e.g., broker-dealer or other borrower in a securities lending transaction) can increase the risk of default by an issuer or counterparty, which can affect a security's or instrument's value or result in delays in recovering securities and/or capital from a counterparty.


      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.


      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.



       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
       .


       &#160;
       You could lose money by investing in the fund.



    </rr:RiskNarrativeTextBlock>
    <rr:RiskNotInsuredDepositoryInstitution contextRef="S000049309SV1-SV2-PRO">
       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
       .
      </rr:RiskNotInsuredDepositoryInstitution>
    <rr:RiskLoseMoney contextRef="S000049309SV1-SV2-PRO">
       &#160;
       You could lose money by investing in the fund.
      </rr:RiskLoseMoney>
    <rr:BarChartAndPerformanceTableHeading contextRef="S000049309SV1-SV2-PRO">
     Performance
    </rr:BarChartAndPerformanceTableHeading>
    <rr:PerformanceNarrativeTextBlock contextRef="S000049309SV1-SV2-PRO">

      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 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.



      Prior to February 18, 2019, the fund was named Fidelity&#xae; SAI U.S. Minimum Volatility Index Fund and the fund operated under certain different investment policies and compared its performance to a different index. The fund's historical performance may not represent its current investment policies.


      Visit

        www.fidelity.com

      for more recent performance information.


    </rr:PerformanceNarrativeTextBlock>
    <rr:PerformanceInformationIllustratesVariabilityOfReturns contextRef="S000049309SV1-SV2-PRO">
       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.
      </rr:PerformanceInformationIllustratesVariabilityOfReturns>
    <rr:PerformancePastDoesNotIndicateFuture contextRef="S000049309SV1-SV2-PRO">
        Past performance (before and after taxes) is not an indication of future performance.
      </rr:PerformancePastDoesNotIndicateFuture>
    <rr:PerformanceAvailabilityWebSiteAddress contextRef="S000049309SV1-SV2-PRO">
        www.fidelity.com
      </rr:PerformanceAvailabilityWebSiteAddress>
    <rr:BarChartHeading contextRef="S000049309SV1-SV2-PRO">
     Year-by-Year Returns
    </rr:BarChartHeading>
    <rr:AnnualReturn2016
      contextRef="S000049309C000155834"
      decimals="INF"
      unitRef="pure">0.1061</rr:AnnualReturn2016>
    <rr:AnnualReturn2017
      contextRef="S000049309C000155834"
      decimals="INF"
      unitRef="pure">0.1892</rr:AnnualReturn2017>
    <rr:AnnualReturn2018
      contextRef="S000049309C000155834"
      decimals="INF"
      unitRef="pure">0.0139</rr:AnnualReturn2018>
    <rr:AnnualReturn2019
      contextRef="S000049309C000155834"
      decimals="INF"
      unitRef="pure">0.2770</rr:AnnualReturn2019>
    <rr:AnnualReturn2020
      contextRef="S000049309C000155834"
      decimals="INF"
      unitRef="pure">0.0985</rr:AnnualReturn2020>
    <rr:AnnualReturn2021
      contextRef="S000049309C000155834"
      decimals="INF"
      unitRef="pure">0.2152</rr:AnnualReturn2021>
    <rr:HighestQuarterlyReturnLabel contextRef="S000049309SV1-SV2-PRO">
         &#160;&#160;&#160;Highest Quarter Return
       </rr:HighestQuarterlyReturnLabel>
    <rr:BarChartHighestQuarterlyReturn
      contextRef="S000049309SV1-SV2-PRO"
      decimals="4"
      unitRef="pure">0.1466</rr:BarChartHighestQuarterlyReturn>
    <rr:BarChartHighestQuarterlyReturnDate contextRef="S000049309SV1-SV2-PRO">2020-06-30</rr:BarChartHighestQuarterlyReturnDate>
    <rr:LowestQuarterlyReturnLabel contextRef="S000049309SV1-SV2-PRO">
         &#160;&#160;&#160;Lowest Quarter Return
       </rr:LowestQuarterlyReturnLabel>
    <rr:BarChartLowestQuarterlyReturn
      contextRef="S000049309SV1-SV2-PRO"
      decimals="4"
      unitRef="pure">-0.1754</rr:BarChartLowestQuarterlyReturn>
    <rr:BarChartLowestQuarterlyReturnDate contextRef="S000049309SV1-SV2-PRO">2020-03-31</rr:BarChartLowestQuarterlyReturnDate>
    <rr:YearToDateReturnLabel contextRef="S000049309SV1-SV2-PRO">
         &#160;&#160;&#160;Year-to-Date Return
       </rr:YearToDateReturnLabel>
    <rr:BarChartYearToDateReturn
      contextRef="S000049309SV1-SV2-PRO"
      decimals="4"
      unitRef="pure">-0.1878</rr:BarChartYearToDateReturn>
    <rr:BarChartYearToDateReturnDate contextRef="S000049309SV1-SV2-PRO">2022-09-30</rr:BarChartYearToDateReturnDate>
    <rr:PerformanceTableHeading contextRef="S000049309SV1-SV2-PRO">
     Average Annual Returns
    </rr:PerformanceTableHeading>
    <rr:PerformanceTableNarrativeTextBlock contextRef="S000049309SV1-SV2-PRO">

      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.

    </rr:PerformanceTableNarrativeTextBlock>
    <rr:PerformanceTableUsesHighestFederalRate contextRef="S000049309SV1-SV2-PRO">
      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.
     </rr:PerformanceTableUsesHighestFederalRate>
    <rr:PerformanceTableNotRelevantToTaxDeferred contextRef="S000049309SV1-SV2-PRO">
       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).
     </rr:PerformanceTableNotRelevantToTaxDeferred>
    <rr:PerformanceTableExplanationAfterTaxHigher contextRef="S000049309SV1-SV2-PRO">
       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.
     </rr:PerformanceTableExplanationAfterTaxHigher>
    <rr:AverageAnnualReturnLabel contextRef="S000049309C000155834ReturnBeforeTaxes">
        Return Before Taxes
       </rr:AverageAnnualReturnLabel>
    <rr:AverageAnnualReturnYear01
      contextRef="S000049309C000155834ReturnBeforeTaxes"
      decimals="4"
      unitRef="pure">0.2152</rr:AverageAnnualReturnYear01>
    <rr:AverageAnnualReturnYear05
      contextRef="S000049309C000155834ReturnBeforeTaxes"
      decimals="4"
      unitRef="pure">0.1550</rr:AverageAnnualReturnYear05>
    <rr:AverageAnnualReturnSinceInception
      contextRef="S000049309C000155834ReturnBeforeTaxes"
      decimals="4"
      id="footnoteSV1-SV2-PROS000049309AAR__RBT"
      unitRef="pure">0.1370</rr:AverageAnnualReturnSinceInception>
    <rr:AverageAnnualReturnLabel contextRef="S000049309C000155834AfterTaxesOnDistributions">
        Return After Taxes on Distributions
       </rr:AverageAnnualReturnLabel>
    <rr:AverageAnnualReturnYear01
      contextRef="S000049309C000155834AfterTaxesOnDistributions"
      decimals="4"
      unitRef="pure">0.2040</rr:AverageAnnualReturnYear01>
    <rr:AverageAnnualReturnYear05
      contextRef="S000049309C000155834AfterTaxesOnDistributions"
      decimals="4"
      unitRef="pure">0.1463</rr:AverageAnnualReturnYear05>
    <rr:AverageAnnualReturnSinceInception
      contextRef="S000049309C000155834AfterTaxesOnDistributions"
      decimals="4"
      id="footnoteSV1-SV2-PROS000049309AAR__ATD"
      unitRef="pure">0.1291</rr:AverageAnnualReturnSinceInception>
    <rr:AverageAnnualReturnLabel contextRef="S000049309C000155834AfterTaxesOnDistributionsAndSales">
        Return After Taxes on Distributions and Sale of Fund Shares
       </rr:AverageAnnualReturnLabel>
    <rr:AverageAnnualReturnYear01
      contextRef="S000049309C000155834AfterTaxesOnDistributionsAndSales"
      decimals="4"
      unitRef="pure">0.1333</rr:AverageAnnualReturnYear01>
    <rr:AverageAnnualReturnYear05
      contextRef="S000049309C000155834AfterTaxesOnDistributionsAndSales"
      decimals="4"
      unitRef="pure">0.1228</rr:AverageAnnualReturnYear05>
    <rr:AverageAnnualReturnSinceInception
      contextRef="S000049309C000155834AfterTaxesOnDistributionsAndSales"
      decimals="4"
      id="footnoteSV1-SV2-PROS000049309AAR__ATDS"
      unitRef="pure">0.1096</rr:AverageAnnualReturnSinceInception>
    <rr:AverageAnnualReturnLabel contextRef="S000049309IndexIXYQMSV1-SV2-PRO">
        Fidelity U.S. Low Volatility Focus Index&#x2120;
       </rr:AverageAnnualReturnLabel>
    <rr:AverageAnnualReturnYear01
      contextRef="S000049309IndexIXYQMSV1-SV2-PRO"
      decimals="4"
      unitRef="pure">0.2162</rr:AverageAnnualReturnYear01>
    <rr:AverageAnnualReturnLabel contextRef="S000049309IndexIXYXNSV1-SV2-PRO">
        Fidelity SAI U.S. Low Volatility Index Fund Linked Index&#x2120;
       </rr:AverageAnnualReturnLabel>
    <rr:AverageAnnualReturnYear01
      contextRef="S000049309IndexIXYXNSV1-SV2-PRO"
      decimals="4"
      unitRef="pure">0.2162</rr:AverageAnnualReturnYear01>
    <rr:AverageAnnualReturnYear05
      contextRef="S000049309IndexIXYXNSV1-SV2-PRO"
      decimals="4"
      unitRef="pure">0.1563</rr:AverageAnnualReturnYear05>
    <rr:AverageAnnualReturnSinceInception
      contextRef="S000049309IndexIXYXNSV1-SV2-PRO"
      decimals="4"
      id="footnoteSV1-SV2-PROS000049309AAR_A_IndexIXYXN"
      unitRef="pure">0.1384</rr:AverageAnnualReturnSinceInception>
    <rr:AnnualReturnInceptionDate contextRef="S000049309SV1-SV2-PRO">2015-05-29</rr:AnnualReturnInceptionDate>
    <rr:RiskReturnHeading contextRef="S000059762IIV-PRO">
  Fund Summary

   Fund:



    Fidelity&#xae; SAI International Value Index Fund



 </rr:RiskReturnHeading>
    <rr:ObjectiveHeading contextRef="S000059762IIV-PRO">
  Investment Objective
 </rr:ObjectiveHeading>
    <rr:ObjectivePrimaryTextBlock contextRef="S000059762IIV-PRO">
  Fidelity&#xae; SAI International Value Index Fund seeks to provide investment results that correspond to the total return of international stocks with attractive valuations.
 </rr:ObjectivePrimaryTextBlock>
    <rr:ExpenseHeading contextRef="S000059762IIV-PRO">
  Fee Table
 </rr:ExpenseHeading>
    <rr:ExpenseNarrativeTextBlock contextRef="S000059762IIV-PRO">

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


 </rr:ExpenseNarrativeTextBlock>
    <rr:ShareholderFeesCaption contextRef="S000059762IIV-PRO">
  Shareholder fees
 </rr:ShareholderFeesCaption>
    <rr:ShareholderFeeOther contextRef="S000059762IIV-PRO" decimals="0" unitRef="usd">0</rr:ShareholderFeeOther>
    <rr:OperatingExpensesCaption contextRef="S000059762IIV-PRO">
  Annual Operating Expenses
 </rr:OperatingExpensesCaption>
    <rr:ManagementFeesOverAssets
      contextRef="S000059762C000195573"
      decimals="6"
      unitRef="pure">0.0015</rr:ManagementFeesOverAssets>
    <rr:DistributionAndService12b1FeesOverAssets
      contextRef="S000059762C000195573"
      decimals="6"
      unitRef="pure">0</rr:DistributionAndService12b1FeesOverAssets>
    <rr:OtherExpensesOverAssets
      contextRef="S000059762C000195573"
      decimals="6"
      unitRef="pure">0.0001</rr:OtherExpensesOverAssets>
    <rr:ExpensesOverAssets
      contextRef="S000059762C000195573"
      decimals="6"
      unitRef="pure">0.0016</rr:ExpensesOverAssets>
    <rr:ExpenseExampleNarrativeTextBlock contextRef="S000059762IIV-PRO">
  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:
 </rr:ExpenseExampleNarrativeTextBlock>
    <rr:ExpenseExampleYear01
      contextRef="S000059762C000195573"
      decimals="0"
      unitRef="usd">16</rr:ExpenseExampleYear01>
    <rr:ExpenseExampleYear03
      contextRef="S000059762C000195573"
      decimals="0"
      unitRef="usd">52</rr:ExpenseExampleYear03>
    <rr:ExpenseExampleYear05
      contextRef="S000059762C000195573"
      decimals="0"
      unitRef="usd">90</rr:ExpenseExampleYear05>
    <rr:ExpenseExampleYear10
      contextRef="S000059762C000195573"
      decimals="0"
      unitRef="usd">205</rr:ExpenseExampleYear10>
    <rr:PortfolioTurnoverHeading contextRef="S000059762IIV-PRO">
   Portfolio Turnover
  </rr:PortfolioTurnoverHeading>
    <rr:PortfolioTurnoverTextBlock contextRef="S000059762IIV-PRO">
   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

     79

   % of the average value of its portfolio.
  </rr:PortfolioTurnoverTextBlock>
    <rr:PortfolioTurnoverRate contextRef="S000059762IIV-PRO" decimals="4" unitRef="pure">0.79</rr:PortfolioTurnoverRate>
    <rr:StrategyHeading contextRef="S000059762IIV-PRO">
   Principal Investment Strategies
  </rr:StrategyHeading>
    <rr:StrategyNarrativeTextBlock contextRef="S000059762IIV-PRO">

    Normally investing at least 80% of assets in securities included in the Fidelity International Value Focus Index&#x2120;.
    Lending securities to earn income for the fund.
    Using statistical sampling techniques based on such factors as capitalization, industry exposures, dividend yield, price/earnings (P/E) ratio, price/book (P/B) ratio, earnings growth, and country weightings to attempt to replicate the returns of the Fidelity International Value Focus Index&#x2120;.


  </rr:StrategyNarrativeTextBlock>
    <rr:RiskHeading contextRef="S000059762IIV-PRO">
   Principal Investment Risks
  </rr:RiskHeading>
    <rr:RiskNarrativeTextBlock contextRef="S000059762IIV-PRO">

    Stock Market Volatility.


    Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.


    Foreign Exposure.


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


    Foreign exchange rates also can be extremely volatile.


    Geographic Exposure to Japan.


    Because the fund invests a meaningful portion of its assets in Japan, the fund's performance is expected to be closely tied to social, political, and economic conditions within Japan and to be more volatile than the performance of more geographically diversified funds.


    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.


    Changes in the financial condition of an issuer or counterparty (e.g., broker-dealer or other borrower in a securities lending transaction) can increase the risk of default by an issuer or counterparty, which can affect a security's or instrument's value or result in delays in recovering securities and/or capital from a counterparty.


    "Value" Investing.


    Although the fund's underlying index uses a rules-based proprietary index methodology that is designed to identify stocks with attractive valuations, there is no guarantee that this methodology will be successful or that these stocks will continue to be good "values." "Value" stocks can perform differently from the market as a whole and other types of stocks and can continue to be undervalued by the market for long periods of time
    .


    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.


    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.


    Securities Lending Risk.


    Securities lending involves the risk that the borrower may fail to return the securities loaned in a timely manner or at all. If the borrower defaults on its obligation to return the securities loaned because of insolvency or other reasons, a fund could experience delays and costs in recovering the securities loaned or in gaining access to the collateral.



     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
     .


     &#160;
     You could lose money by investing in the fund.



  </rr:RiskNarrativeTextBlock>
    <rr:RiskNotInsuredDepositoryInstitution contextRef="S000059762IIV-PRO">
     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
     .
    </rr:RiskNotInsuredDepositoryInstitution>
    <rr:RiskLoseMoney contextRef="S000059762IIV-PRO">
     &#160;
     You could lose money by investing in the fund.
    </rr:RiskLoseMoney>
    <rr:BarChartAndPerformanceTableHeading contextRef="S000059762IIV-PRO">
   Performance
  </rr:BarChartAndPerformanceTableHeading>
    <rr:PerformanceNarrativeTextBlock contextRef="S000059762IIV-PRO">

    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.


  </rr:PerformanceNarrativeTextBlock>
    <rr:PerformanceInformationIllustratesVariabilityOfReturns contextRef="S000059762IIV-PRO">
     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.
    </rr:PerformanceInformationIllustratesVariabilityOfReturns>
    <rr:PerformancePastDoesNotIndicateFuture contextRef="S000059762IIV-PRO">
      Past performance (before and after taxes) is not an indication of future performance.
    </rr:PerformancePastDoesNotIndicateFuture>
    <rr:PerformanceAvailabilityWebSiteAddress contextRef="S000059762IIV-PRO">
      www.fidelity.com
    </rr:PerformanceAvailabilityWebSiteAddress>
    <rr:BarChartHeading contextRef="S000059762IIV-PRO">
   Year-by-Year Returns
  </rr:BarChartHeading>
    <rr:AnnualReturn2018
      contextRef="S000059762C000195573"
      decimals="INF"
      unitRef="pure">-0.1611</rr:AnnualReturn2018>
    <rr:AnnualReturn2019
      contextRef="S000059762C000195573"
      decimals="INF"
      unitRef="pure">0.1726</rr:AnnualReturn2019>
    <rr:AnnualReturn2020
      contextRef="S000059762C000195573"
      decimals="INF"
      unitRef="pure">-0.0393</rr:AnnualReturn2020>
    <rr:AnnualReturn2021
      contextRef="S000059762C000195573"
      decimals="INF"
      unitRef="pure">0.1384</rr:AnnualReturn2021>
    <rr:HighestQuarterlyReturnLabel contextRef="S000059762IIV-PRO">
       &#160;&#160;&#160;Highest Quarter Return
     </rr:HighestQuarterlyReturnLabel>
    <rr:BarChartHighestQuarterlyReturn contextRef="S000059762IIV-PRO" decimals="4" unitRef="pure">0.1939</rr:BarChartHighestQuarterlyReturn>
    <rr:BarChartHighestQuarterlyReturnDate contextRef="S000059762IIV-PRO">2020-12-31</rr:BarChartHighestQuarterlyReturnDate>
    <rr:LowestQuarterlyReturnLabel contextRef="S000059762IIV-PRO">
       &#160;&#160;&#160;Lowest Quarter Return
     </rr:LowestQuarterlyReturnLabel>
    <rr:BarChartLowestQuarterlyReturn contextRef="S000059762IIV-PRO" decimals="4" unitRef="pure">-0.2956</rr:BarChartLowestQuarterlyReturn>
    <rr:BarChartLowestQuarterlyReturnDate contextRef="S000059762IIV-PRO">2020-03-31</rr:BarChartLowestQuarterlyReturnDate>
    <rr:YearToDateReturnLabel contextRef="S000059762IIV-PRO">
       &#160;&#160;&#160;Year-to-Date Return
     </rr:YearToDateReturnLabel>
    <rr:BarChartYearToDateReturn contextRef="S000059762IIV-PRO" decimals="4" unitRef="pure">-0.2289</rr:BarChartYearToDateReturn>
    <rr:BarChartYearToDateReturnDate contextRef="S000059762IIV-PRO">2022-09-30</rr:BarChartYearToDateReturnDate>
    <rr:PerformanceTableHeading contextRef="S000059762IIV-PRO">
   Average Annual Returns
  </rr:PerformanceTableHeading>
    <rr:PerformanceTableNarrativeTextBlock contextRef="S000059762IIV-PRO">

    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.

  </rr:PerformanceTableNarrativeTextBlock>
    <rr:PerformanceTableUsesHighestFederalRate contextRef="S000059762IIV-PRO">
    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.
   </rr:PerformanceTableUsesHighestFederalRate>
    <rr:PerformanceTableNotRelevantToTaxDeferred contextRef="S000059762IIV-PRO">
     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).
   </rr:PerformanceTableNotRelevantToTaxDeferred>
    <rr:PerformanceTableExplanationAfterTaxHigher contextRef="S000059762IIV-PRO">
     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.
   </rr:PerformanceTableExplanationAfterTaxHigher>
    <rr:AverageAnnualReturnLabel contextRef="S000059762C000195573ReturnBeforeTaxes">
      Return Before Taxes
     </rr:AverageAnnualReturnLabel>
    <rr:AverageAnnualReturnYear01
      contextRef="S000059762C000195573ReturnBeforeTaxes"
      decimals="4"
      unitRef="pure">0.1384</rr:AverageAnnualReturnYear01>
    <rr:AverageAnnualReturnSinceInception
      contextRef="S000059762C000195573ReturnBeforeTaxes"
      decimals="4"
      id="footnoteIIV-PROS000059762AAR__RBT"
      unitRef="pure">0.0202</rr:AverageAnnualReturnSinceInception>
    <rr:AverageAnnualReturnLabel contextRef="S000059762C000195573AfterTaxesOnDistributions">
      Return After Taxes on Distributions
     </rr:AverageAnnualReturnLabel>
    <rr:AverageAnnualReturnYear01
      contextRef="S000059762C000195573AfterTaxesOnDistributions"
      decimals="4"
      unitRef="pure">0.1108</rr:AverageAnnualReturnYear01>
    <rr:AverageAnnualReturnSinceInception
      contextRef="S000059762C000195573AfterTaxesOnDistributions"
      decimals="4"
      id="footnoteIIV-PROS000059762AAR__ATD"
      unitRef="pure">0.0106</rr:AverageAnnualReturnSinceInception>
    <rr:AverageAnnualReturnLabel contextRef="S000059762C000195573AfterTaxesOnDistributionsAndSales">
      Return After Taxes on Distributions and Sale of Fund Shares
     </rr:AverageAnnualReturnLabel>
    <rr:AverageAnnualReturnYear01
      contextRef="S000059762C000195573AfterTaxesOnDistributionsAndSales"
      decimals="4"
      unitRef="pure">0.0919</rr:AverageAnnualReturnYear01>
    <rr:AverageAnnualReturnSinceInception
      contextRef="S000059762C000195573AfterTaxesOnDistributionsAndSales"
      decimals="4"
      id="footnoteIIV-PROS000059762AAR__ATDS"
      unitRef="pure">0.0145</rr:AverageAnnualReturnSinceInception>
    <rr:AverageAnnualReturnLabel contextRef="S000059762IndexIXYEHIIV-PRO">
      Fidelity International Value Focus Index&#x2120;
     </rr:AverageAnnualReturnLabel>
    <rr:AverageAnnualReturnYear01
      contextRef="S000059762IndexIXYEHIIV-PRO"
      decimals="4"
      unitRef="pure">0.1420</rr:AverageAnnualReturnYear01>
    <rr:AverageAnnualReturnSinceInception
      contextRef="S000059762IndexIXYEHIIV-PRO"
      decimals="4"
      id="footnoteIIV-PROS000059762AAR_A_IndexIXYEH"
      unitRef="pure">0.0250</rr:AverageAnnualReturnSinceInception>
    <rr:AnnualReturnInceptionDate contextRef="S000059762IIV-PRO">2017-12-19</rr:AnnualReturnInceptionDate>
    <rr:RiskReturnHeading contextRef="S000051995SV6-PRO">
  Fund Summary

   Fund:



    Fidelity&#xae; SAI Emerging Markets Index Fund



 </rr:RiskReturnHeading>
    <rr:ObjectiveHeading contextRef="S000051995SV6-PRO">
  Investment Objective
 </rr:ObjectiveHeading>
    <rr:ObjectivePrimaryTextBlock contextRef="S000051995SV6-PRO">
  Fidelity&#xae; SAI Emerging Markets Index Fund seeks to provide investment results that correspond to the total return of emerging stock markets.
 </rr:ObjectivePrimaryTextBlock>
    <rr:ExpenseHeading contextRef="S000051995SV6-PRO">
  Fee Table
 </rr:ExpenseHeading>
    <rr:ExpenseNarrativeTextBlock contextRef="S000051995SV6-PRO">

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


 </rr:ExpenseNarrativeTextBlock>
    <rr:ShareholderFeesCaption contextRef="S000051995SV6-PRO">
  Shareholder fees
 </rr:ShareholderFeesCaption>
    <rr:ShareholderFeeOther contextRef="S000051995SV6-PRO" decimals="0" unitRef="usd">0</rr:ShareholderFeeOther>
    <rr:OperatingExpensesCaption contextRef="S000051995SV6-PRO">
  Annual Operating Expenses
 </rr:OperatingExpensesCaption>
    <rr:ManagementFeesOverAssets
      contextRef="S000051995C000163541"
      decimals="6"
      unitRef="pure">0.00075</rr:ManagementFeesOverAssets>
    <rr:DistributionAndService12b1FeesOverAssets
      contextRef="S000051995C000163541"
      decimals="6"
      unitRef="pure">0</rr:DistributionAndService12b1FeesOverAssets>
    <rr:OtherExpensesOverAssets
      contextRef="S000051995C000163541"
      decimals="6"
      unitRef="pure">0.00073</rr:OtherExpensesOverAssets>
    <rr:ExpensesOverAssets
      contextRef="S000051995C000163541"
      decimals="6"
      unitRef="pure">0.00148</rr:ExpensesOverAssets>
    <rr:FeeWaiverOrReimbursementOverAssets
      contextRef="S000051995C000163541"
      decimals="6"
      id="footnoteSV6-PROAOE_A_FW"
      unitRef="pure">-0.00073</rr:FeeWaiverOrReimbursementOverAssets>
    <rr:NetExpensesOverAssets
      contextRef="S000051995C000163541"
      decimals="6"
      unitRef="pure">0.00075</rr:NetExpensesOverAssets>
    <rr:FeeWaiverOrReimbursementOverAssetsDateOfTermination contextRef="S000051995SV6-PRO">
   February 29, 2024
  </rr:FeeWaiverOrReimbursementOverAssetsDateOfTermination>
    <rr:ExpenseExampleNarrativeTextBlock contextRef="S000051995SV6-PRO">
  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:
 </rr:ExpenseExampleNarrativeTextBlock>
    <rr:ExpenseExampleYear01
      contextRef="S000051995C000163541"
      decimals="0"
      unitRef="usd">8</rr:ExpenseExampleYear01>
    <rr:ExpenseExampleYear03
      contextRef="S000051995C000163541"
      decimals="0"
      unitRef="usd">38</rr:ExpenseExampleYear03>
    <rr:ExpenseExampleYear05
      contextRef="S000051995C000163541"
      decimals="0"
      unitRef="usd">73</rr:ExpenseExampleYear05>
    <rr:ExpenseExampleYear10
      contextRef="S000051995C000163541"
      decimals="0"
      unitRef="usd">179</rr:ExpenseExampleYear10>
    <rr:PortfolioTurnoverHeading contextRef="S000051995SV6-PRO">
   Portfolio Turnover
  </rr:PortfolioTurnoverHeading>
    <rr:PortfolioTurnoverTextBlock contextRef="S000051995SV6-PRO">
   The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was

     30

   % of the average value of its portfolio.
  </rr:PortfolioTurnoverTextBlock>
    <rr:PortfolioTurnoverRate contextRef="S000051995SV6-PRO" decimals="4" unitRef="pure">0.30</rr:PortfolioTurnoverRate>
    <rr:StrategyHeading contextRef="S000051995SV6-PRO">
   Principal Investment Strategies
  </rr:StrategyHeading>
    <rr:StrategyNarrativeTextBlock contextRef="S000051995SV6-PRO">

    Normally investing at least 80% of assets in securities included in the MSCI Emerging Markets Index and in depositary receipts representing securities included in the index.
    Lending securities to earn income for the fund.
    Using statistical sampling techniques based on such factors as capitalization, industry exposures, dividend yield, price/earnings (P/E) ratio, price/book (P/B) ratio, earnings growth, and country weightings to attempt to replicate the returns of the MSCI Emerging Markets Index.


  </rr:StrategyNarrativeTextBlock>
    <rr:RiskHeading contextRef="S000051995SV6-PRO">
   Principal Investment Risks
  </rr:RiskHeading>
    <rr:RiskNarrativeTextBlock contextRef="S000051995SV6-PRO">

    Stock Market Volatility.


    Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.


    Foreign and Emerging Markets Risk.


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


    The extent of economic development; political stability; market depth, infrastructure, and capitalization; and regulatory oversight can be less than in more developed markets. Emerging markets typically have less established legal, accounting and financial reporting systems than those in more developed markets, which may reduce the scope or quality of financial information available to investors.


    Emerging markets can be subject to greater social, economic, regulatory, and political uncertainties and can be extremely volatile.


    Foreign exchange rates also can be extremely volatile.


    Geographic Exposure to China.


    Because the fund invests a meaningful portion of its assets in China, the fund's performance is expected to be closely tied to social, political, and economic conditions in China and to be more volatile than the performance of more geographically diversified funds. The fund may obtain exposure to companies based or operated in China by investing through legal structures known as variable interest entities (VIEs). Instead of directly owning the equity securities of a Chinese company, a VIE enters into service and other contracts with the Chinese company. Although the VIE has no equity ownership of the Chinese company, the contractual arrangements permit the VIE to consolidate the Chinese company into its financial statements. Intervention by the Chinese government with respect to VIEs could significantly affect the Chinese company's performance and the enforceability of the VIE's contractual arrangements with the Chinese company.


    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.


    Changes in the financial condition of an issuer or counterparty (e.g., broker-dealer or other borrower in a securities lending transaction) can increase the risk of default by an issuer or counterparty, which can affect a security's or instrument's value or result in delays in recovering securities and/or capital from a counterparty.


    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.


    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.


    Securities Lending Risk.


    Securities lending involves the risk that the borrower may fail to return the securities loaned in a timely manner or at all. If the borrower defaults on its obligation to return the securities loaned because of insolvency or other reasons, a fund could experience delays and costs in recovering the securities loaned or in gaining access to the collateral.



     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
     .


     &#160;
     You could lose money by investing in the fund.



  </rr:RiskNarrativeTextBlock>
    <rr:RiskNotInsuredDepositoryInstitution contextRef="S000051995SV6-PRO">
     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
     .
    </rr:RiskNotInsuredDepositoryInstitution>
    <rr:RiskLoseMoney contextRef="S000051995SV6-PRO">
     &#160;
     You could lose money by investing in the fund.
    </rr:RiskLoseMoney>
    <rr:BarChartAndPerformanceTableHeading contextRef="S000051995SV6-PRO">
   Performance
  </rr:BarChartAndPerformanceTableHeading>
    <rr:PerformanceNarrativeTextBlock contextRef="S000051995SV6-PRO">

    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.


  </rr:PerformanceNarrativeTextBlock>
    <rr:PerformanceInformationIllustratesVariabilityOfReturns contextRef="S000051995SV6-PRO">
     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.
    </rr:PerformanceInformationIllustratesVariabilityOfReturns>
    <rr:PerformancePastDoesNotIndicateFuture contextRef="S000051995SV6-PRO">
      Past performance (before and after taxes) is not an indication of future performance.
    </rr:PerformancePastDoesNotIndicateFuture>
    <rr:PerformanceAvailabilityWebSiteAddress contextRef="S000051995SV6-PRO">
      www.fidelity.com
    </rr:PerformanceAvailabilityWebSiteAddress>
    <rr:BarChartHeading contextRef="S000051995SV6-PRO">
   Year-by-Year Returns
  </rr:BarChartHeading>
    <rr:AnnualReturn2017
      contextRef="S000051995C000163541"
      decimals="INF"
      unitRef="pure">0.3760</rr:AnnualReturn2017>
    <rr:AnnualReturn2018
      contextRef="S000051995C000163541"
      decimals="INF"
      unitRef="pure">-0.1448</rr:AnnualReturn2018>
    <rr:AnnualReturn2019
      contextRef="S000051995C000163541"
      decimals="INF"
      unitRef="pure">0.1820</rr:AnnualReturn2019>
    <rr:AnnualReturn2020
      contextRef="S000051995C000163541"
      decimals="INF"
      unitRef="pure">0.1744</rr:AnnualReturn2020>
    <rr:AnnualReturn2021
      contextRef="S000051995C000163541"
      decimals="INF"
      unitRef="pure">-0.0300</rr:AnnualReturn2021>
    <rr:HighestQuarterlyReturnLabel contextRef="S000051995SV6-PRO">
       &#160;&#160;&#160;Highest Quarter Return
     </rr:HighestQuarterlyReturnLabel>
    <rr:BarChartHighestQuarterlyReturn contextRef="S000051995SV6-PRO" decimals="4" unitRef="pure">0.1879</rr:BarChartHighestQuarterlyReturn>
    <rr:BarChartHighestQuarterlyReturnDate contextRef="S000051995SV6-PRO">2020-06-30</rr:BarChartHighestQuarterlyReturnDate>
    <rr:LowestQuarterlyReturnLabel contextRef="S000051995SV6-PRO">
       &#160;&#160;&#160;Lowest Quarter Return
     </rr:LowestQuarterlyReturnLabel>
    <rr:BarChartLowestQuarterlyReturn contextRef="S000051995SV6-PRO" decimals="4" unitRef="pure">-0.2408</rr:BarChartLowestQuarterlyReturn>
    <rr:BarChartLowestQuarterlyReturnDate contextRef="S000051995SV6-PRO">2020-03-31</rr:BarChartLowestQuarterlyReturnDate>
    <rr:YearToDateReturnLabel contextRef="S000051995SV6-PRO">
       &#160;&#160;&#160;Year-to-Date Return
     </rr:YearToDateReturnLabel>
    <rr:BarChartYearToDateReturn contextRef="S000051995SV6-PRO" decimals="4" unitRef="pure">-0.2733</rr:BarChartYearToDateReturn>
    <rr:BarChartYearToDateReturnDate contextRef="S000051995SV6-PRO">2022-09-30</rr:BarChartYearToDateReturnDate>
    <rr:PerformanceTableHeading contextRef="S000051995SV6-PRO">
   Average Annual Returns
  </rr:PerformanceTableHeading>
    <rr:PerformanceTableNarrativeTextBlock contextRef="S000051995SV6-PRO">

    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.

  </rr:PerformanceTableNarrativeTextBlock>
    <rr:PerformanceTableUsesHighestFederalRate contextRef="S000051995SV6-PRO">
    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.
   </rr:PerformanceTableUsesHighestFederalRate>
    <rr:PerformanceTableNotRelevantToTaxDeferred contextRef="S000051995SV6-PRO">
     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).
   </rr:PerformanceTableNotRelevantToTaxDeferred>
    <rr:PerformanceTableExplanationAfterTaxHigher contextRef="S000051995SV6-PRO">
     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.
   </rr:PerformanceTableExplanationAfterTaxHigher>
    <rr:AverageAnnualReturnLabel contextRef="S000051995C000163541ReturnBeforeTaxes">
      Return Before Taxes
     </rr:AverageAnnualReturnLabel>
    <rr:AverageAnnualReturnYear01
      contextRef="S000051995C000163541ReturnBeforeTaxes"
      decimals="4"
      unitRef="pure">-0.0300</rr:AverageAnnualReturnYear01>
    <rr:AverageAnnualReturnYear05
      contextRef="S000051995C000163541ReturnBeforeTaxes"
      decimals="4"
      unitRef="pure">0.0964</rr:AverageAnnualReturnYear05>
    <rr:AverageAnnualReturnSinceInception
      contextRef="S000051995C000163541ReturnBeforeTaxes"
      decimals="4"
      id="footnoteSV6-PROS000051995AAR__RBT"
      unitRef="pure">0.1030</rr:AverageAnnualReturnSinceInception>
    <rr:AverageAnnualReturnLabel contextRef="S000051995C000163541AfterTaxesOnDistributions">
      Return After Taxes on Distributions
     </rr:AverageAnnualReturnLabel>
    <rr:AverageAnnualReturnYear01
      contextRef="S000051995C000163541AfterTaxesOnDistributions"
      decimals="4"
      unitRef="pure">-0.0376</rr:AverageAnnualReturnYear01>
    <rr:AverageAnnualReturnYear05
      contextRef="S000051995C000163541AfterTaxesOnDistributions"
      decimals="4"
      unitRef="pure">0.0904</rr:AverageAnnualReturnYear05>
    <rr:AverageAnnualReturnSinceInception
      contextRef="S000051995C000163541AfterTaxesOnDistributions"
      decimals="4"
      id="footnoteSV6-PROS000051995AAR__ATD"
      unitRef="pure">0.0970</rr:AverageAnnualReturnSinceInception>
    <rr:AverageAnnualReturnLabel contextRef="S000051995C000163541AfterTaxesOnDistributionsAndSales">
      Return After Taxes on Distributions and Sale of Fund Shares
     </rr:AverageAnnualReturnLabel>
    <rr:AverageAnnualReturnYear01
      contextRef="S000051995C000163541AfterTaxesOnDistributionsAndSales"
      decimals="4"
      unitRef="pure">-0.0141</rr:AverageAnnualReturnYear01>
    <rr:AverageAnnualReturnYear05
      contextRef="S000051995C000163541AfterTaxesOnDistributionsAndSales"
      decimals="4"
      unitRef="pure">0.0760</rr:AverageAnnualReturnYear05>
    <rr:AverageAnnualReturnSinceInception
      contextRef="S000051995C000163541AfterTaxesOnDistributionsAndSales"
      decimals="4"
      id="footnoteSV6-PROS000051995AAR__ATDS"
      unitRef="pure">0.0818</rr:AverageAnnualReturnSinceInception>
    <rr:AverageAnnualReturnLabel contextRef="S000051995IndexMC041SV6-PRO">
      MSCI Emerging Markets Index
     </rr:AverageAnnualReturnLabel>
    <rr:AverageAnnualReturnYear01
      contextRef="S000051995IndexMC041SV6-PRO"
      decimals="4"
      unitRef="pure">-0.0253</rr:AverageAnnualReturnYear01>
    <rr:AverageAnnualReturnYear05
      contextRef="S000051995IndexMC041SV6-PRO"
      decimals="4"
      unitRef="pure">0.0990</rr:AverageAnnualReturnYear05>
    <rr:AverageAnnualReturnSinceInception
      contextRef="S000051995IndexMC041SV6-PRO"
      decimals="4"
      id="footnoteSV6-PROS000051995AAR_A_IndexMC041"
      unitRef="pure">0.1074</rr:AverageAnnualReturnSinceInception>
    <rr:AnnualReturnInceptionDate contextRef="S000051995SV6-PRO">2016-01-05</rr:AnnualReturnInceptionDate>
    <rr:RiskReturnHeading contextRef="S000057365USY-I-ISY-I-PRO">
  Fund Summary

   Fund:



    Fidelity&#xae; International Sustainability Index Fund



 </rr:RiskReturnHeading>
    <rr:ObjectiveHeading contextRef="S000057365USY-I-ISY-I-PRO">
  Investment Objective
 </rr:ObjectiveHeading>
    <rr:ObjectivePrimaryTextBlock contextRef="S000057365USY-I-ISY-I-PRO">
  Fidelity&#xae; International Sustainability Index Fund seeks to provide investment results that correspond to the total return of the MSCI ACWI (All Country World Index) ex USA ESG Leaders Index.
 </rr:ObjectivePrimaryTextBlock>
    <rr:ExpenseHeading contextRef="S000057365USY-I-ISY-I-PRO">
  Fee Table
 </rr:ExpenseHeading>
    <rr:ExpenseNarrativeTextBlock contextRef="S000057365USY-I-ISY-I-PRO">

   The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund.
   In addition to the fees and expenses described below, your broker may also require you to pay brokerage commissions on purchases and sales of the fund.


 </rr:ExpenseNarrativeTextBlock>
    <rr:ShareholderFeesCaption contextRef="S000057365USY-I-ISY-I-PRO">
  Shareholder fees
 </rr:ShareholderFeesCaption>
    <rr:ShareholderFeeOther
      contextRef="S000057365USY-I-ISY-I-PRO"
      decimals="0"
      unitRef="usd">0</rr:ShareholderFeeOther>
    <rr:OperatingExpensesCaption contextRef="S000057365USY-I-ISY-I-PRO">
  Annual Operating Expenses
 </rr:OperatingExpensesCaption>
    <rr:ManagementFeesOverAssets
      contextRef="S000057365C000183133"
      decimals="6"
      unitRef="pure">0.0020</rr:ManagementFeesOverAssets>
    <rr:DistributionAndService12b1FeesOverAssets
      contextRef="S000057365C000183133"
      decimals="6"
      unitRef="pure">0</rr:DistributionAndService12b1FeesOverAssets>
    <rr:OtherExpensesOverAssets
      contextRef="S000057365C000183133"
      decimals="6"
      unitRef="pure">0.0000</rr:OtherExpensesOverAssets>
    <rr:ExpensesOverAssets
      contextRef="S000057365C000183133"
      decimals="6"
      unitRef="pure">0.0020</rr:ExpensesOverAssets>
    <rr:ExpenseExampleNarrativeTextBlock contextRef="S000057365USY-I-ISY-I-PRO">
  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:
 </rr:ExpenseExampleNarrativeTextBlock>
    <rr:ExpenseExampleYear01
      contextRef="S000057365C000183133"
      decimals="0"
      unitRef="usd">20</rr:ExpenseExampleYear01>
    <rr:ExpenseExampleYear03
      contextRef="S000057365C000183133"
      decimals="0"
      unitRef="usd">64</rr:ExpenseExampleYear03>
    <rr:ExpenseExampleYear05
      contextRef="S000057365C000183133"
      decimals="0"
      unitRef="usd">113</rr:ExpenseExampleYear05>
    <rr:ExpenseExampleYear10
      contextRef="S000057365C000183133"
      decimals="0"
      unitRef="usd">255</rr:ExpenseExampleYear10>
    <rr:PortfolioTurnoverHeading contextRef="S000057365USY-I-ISY-I-PRO">
   Portfolio Turnover
  </rr:PortfolioTurnoverHeading>
    <rr:PortfolioTurnoverTextBlock contextRef="S000057365USY-I-ISY-I-PRO">
   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.
  </rr:PortfolioTurnoverTextBlock>
    <rr:PortfolioTurnoverRate
      contextRef="S000057365USY-I-ISY-I-PRO"
      decimals="4"
      unitRef="pure">0.23</rr:PortfolioTurnoverRate>
    <rr:StrategyHeading contextRef="S000057365USY-I-ISY-I-PRO">
   Principal Investment Strategies
  </rr:StrategyHeading>
    <rr:StrategyNarrativeTextBlock contextRef="S000057365USY-I-ISY-I-PRO">

    Normally investing at least 80% of assets in securities included in the MSCI ACWI (All Country World Index) ex USA ESG Leaders Index and in depositary receipts representing securities included in the index. The MSCI ACWI (All Country World Index) ex USA ESG Leaders Index is a capitalization-weighted index that provides exposure to companies with high environmental, social, and governance (ESG) performance relative to their sector peers, as rated by MSCI ESG Research. The MSCI ACWI (All Country World Index) ex USA ESG Leaders Index consists of large- and mid-cap companies across developed and emerging markets, excluding the United States.
    Using statistical sampling techniques based on such factors as capitalization, industry exposures, dividend yield, price/earnings (P/E) ratio, price/book (P/B) ratio, earnings growth, country weightings, and the effect of foreign taxes to attempt to replicate the returns of the MSCI ACWI (All Country World Index) ex USA ESG Leaders Index.
    Lending securities to earn income for the fund.


  </rr:StrategyNarrativeTextBlock>
    <rr:RiskHeading contextRef="S000057365USY-I-ISY-I-PRO">
   Principal Investment Risks
  </rr:RiskHeading>
    <rr:RiskNarrativeTextBlock contextRef="S000057365USY-I-ISY-I-PRO">

    Stock Market Volatility.


    Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.


    Foreign and Emerging Markets Risk.


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


    The extent of economic development; political stability; market depth, infrastructure, and capitalization; and regulatory oversight can be less than in more developed markets. Emerging markets typically have less established legal, accounting and financial reporting systems than those in more developed markets, which may reduce the scope or quality of financial information available to investors.


    Emerging markets can be subject to greater social, economic, regulatory, and political uncertainties and can be extremely volatile.


    Foreign exchange rates also can be extremely volatile.


    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.


    Changes in the financial condition of an issuer or counterparty (e.g., broker-dealer or other borrower in a securities lending transaction) can increase the risk of default by an issuer or counterparty, which can affect a security's or instrument's value or result in delays in recovering securities and/or capital from a counterparty.


    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.


    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.


    Securities Lending Risk.


    Securities lending involves the risk that the borrower may fail to return the securities loaned in a timely manner or at all. If the borrower defaults on its obligation to return the securities loaned because of insolvency or other reasons, a fund could experience delays and costs in recovering the securities loaned or in gaining access to the collateral.



     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
     .


     &#160;
     You could lose money by investing in the fund.



  </rr:RiskNarrativeTextBlock>
    <rr:RiskNotInsuredDepositoryInstitution contextRef="S000057365USY-I-ISY-I-PRO">
     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
     .
    </rr:RiskNotInsuredDepositoryInstitution>
    <rr:RiskLoseMoney contextRef="S000057365USY-I-ISY-I-PRO">
     &#160;
     You could lose money by investing in the fund.
    </rr:RiskLoseMoney>
    <rr:BarChartAndPerformanceTableHeading contextRef="S000057365USY-I-ISY-I-PRO">
   Performance
  </rr:BarChartAndPerformanceTableHeading>
    <rr:PerformanceNarrativeTextBlock contextRef="S000057365USY-I-ISY-I-PRO">

    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.


  </rr:PerformanceNarrativeTextBlock>
    <rr:PerformanceInformationIllustratesVariabilityOfReturns contextRef="S000057365USY-I-ISY-I-PRO">
     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.
    </rr:PerformanceInformationIllustratesVariabilityOfReturns>
    <rr:PerformancePastDoesNotIndicateFuture contextRef="S000057365USY-I-ISY-I-PRO">
      Past performance (before and after taxes) is not an indication of future performance.
    </rr:PerformancePastDoesNotIndicateFuture>
    <rr:PerformanceAvailabilityWebSiteAddress contextRef="S000057365USY-I-ISY-I-PRO">
      www.fidelity.com
    </rr:PerformanceAvailabilityWebSiteAddress>
    <rr:BarChartHeading contextRef="S000057365USY-I-ISY-I-PRO">
   Year-by-Year Returns
  </rr:BarChartHeading>
    <rr:AnnualReturn2018
      contextRef="S000057365C000183133"
      decimals="INF"
      unitRef="pure">-0.1399</rr:AnnualReturn2018>
    <rr:AnnualReturn2019
      contextRef="S000057365C000183133"
      decimals="INF"
      unitRef="pure">0.2218</rr:AnnualReturn2019>
    <rr:AnnualReturn2020
      contextRef="S000057365C000183133"
      decimals="INF"
      unitRef="pure">0.1298</rr:AnnualReturn2020>
    <rr:AnnualReturn2021
      contextRef="S000057365C000183133"
      decimals="INF"
      unitRef="pure">0.0765</rr:AnnualReturn2021>
    <rr:HighestQuarterlyReturnLabel contextRef="S000057365USY-I-ISY-I-PRO">
       &#160;&#160;&#160;Highest Quarter Return
     </rr:HighestQuarterlyReturnLabel>
    <rr:BarChartHighestQuarterlyReturn
      contextRef="S000057365USY-I-ISY-I-PRO"
      decimals="4"
      unitRef="pure">0.1775</rr:BarChartHighestQuarterlyReturn>
    <rr:BarChartHighestQuarterlyReturnDate contextRef="S000057365USY-I-ISY-I-PRO">2020-06-30</rr:BarChartHighestQuarterlyReturnDate>
    <rr:LowestQuarterlyReturnLabel contextRef="S000057365USY-I-ISY-I-PRO">
       &#160;&#160;&#160;Lowest Quarter Return
     </rr:LowestQuarterlyReturnLabel>
    <rr:BarChartLowestQuarterlyReturn
      contextRef="S000057365USY-I-ISY-I-PRO"
      decimals="4"
      unitRef="pure">-0.2212</rr:BarChartLowestQuarterlyReturn>
    <rr:BarChartLowestQuarterlyReturnDate contextRef="S000057365USY-I-ISY-I-PRO">2020-03-31</rr:BarChartLowestQuarterlyReturnDate>
    <rr:YearToDateReturnLabel contextRef="S000057365USY-I-ISY-I-PRO">
       &#160;&#160;&#160;Year-to-Date Return
     </rr:YearToDateReturnLabel>
    <rr:BarChartYearToDateReturn
      contextRef="S000057365USY-I-ISY-I-PRO"
      decimals="4"
      unitRef="pure">-0.2958</rr:BarChartYearToDateReturn>
    <rr:BarChartYearToDateReturnDate contextRef="S000057365USY-I-ISY-I-PRO">2022-09-30</rr:BarChartYearToDateReturnDate>
    <rr:PerformanceTableHeading contextRef="S000057365USY-I-ISY-I-PRO">
   Average Annual Returns
  </rr:PerformanceTableHeading>
    <rr:PerformanceTableNarrativeTextBlock contextRef="S000057365USY-I-ISY-I-PRO">

    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.

  </rr:PerformanceTableNarrativeTextBlock>
    <rr:PerformanceTableUsesHighestFederalRate contextRef="S000057365USY-I-ISY-I-PRO">
    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.
   </rr:PerformanceTableUsesHighestFederalRate>
    <rr:PerformanceTableNotRelevantToTaxDeferred contextRef="S000057365USY-I-ISY-I-PRO">
     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).
   </rr:PerformanceTableNotRelevantToTaxDeferred>
    <rr:PerformanceTableExplanationAfterTaxHigher contextRef="S000057365USY-I-ISY-I-PRO">
     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.
   </rr:PerformanceTableExplanationAfterTaxHigher>
    <rr:AverageAnnualReturnLabel contextRef="S000057365C000183133ReturnBeforeTaxes">
      Return Before Taxes
     </rr:AverageAnnualReturnLabel>
    <rr:AverageAnnualReturnYear01
      contextRef="S000057365C000183133ReturnBeforeTaxes"
      decimals="4"
      unitRef="pure">0.0765</rr:AverageAnnualReturnYear01>
    <rr:AverageAnnualReturnSinceInception
      contextRef="S000057365C000183133ReturnBeforeTaxes"
      decimals="4"
      id="footnoteUSY-I-ISY-I-PROS000057365AAR__RBT"
      unitRef="pure">0.0822</rr:AverageAnnualReturnSinceInception>
    <rr:AverageAnnualReturnLabel contextRef="S000057365C000183133AfterTaxesOnDistributions">
      Return After Taxes on Distributions
     </rr:AverageAnnualReturnLabel>
    <rr:AverageAnnualReturnYear01
      contextRef="S000057365C000183133AfterTaxesOnDistributions"
      decimals="4"
      unitRef="pure">0.0726</rr:AverageAnnualReturnYear01>
    <rr:AverageAnnualReturnSinceInception
      contextRef="S000057365C000183133AfterTaxesOnDistributions"
      decimals="4"
      id="footnoteUSY-I-ISY-I-PROS000057365AAR__ATD"
      unitRef="pure">0.0784</rr:AverageAnnualReturnSinceInception>
    <rr:AverageAnnualReturnLabel contextRef="S000057365C000183133AfterTaxesOnDistributionsAndSales">
      Return After Taxes on Distributions and Sale of Fund Shares
     </rr:AverageAnnualReturnLabel>
    <rr:AverageAnnualReturnYear01
      contextRef="S000057365C000183133AfterTaxesOnDistributionsAndSales"
      decimals="4"
      unitRef="pure">0.0497</rr:AverageAnnualReturnYear01>
    <rr:AverageAnnualReturnSinceInception
      contextRef="S000057365C000183133AfterTaxesOnDistributionsAndSales"
      decimals="4"
      id="footnoteUSY-I-ISY-I-PROS000057365AAR__ATDS"
      unitRef="pure">0.0650</rr:AverageAnnualReturnSinceInception>
    <rr:AverageAnnualReturnLabel contextRef="S000057365IndexIXWWZUSY-I-ISY-I-PRO">
      MSCI ACWI (All Country World Index) ex USA ESG Leaders Index (gross)
     </rr:AverageAnnualReturnLabel>
    <rr:AverageAnnualReturnYear01
      contextRef="S000057365IndexIXWWZUSY-I-ISY-I-PRO"
      decimals="4"
      unitRef="pure">0.0843</rr:AverageAnnualReturnYear01>
    <rr:AverageAnnualReturnSinceInception
      contextRef="S000057365IndexIXWWZUSY-I-ISY-I-PRO"
      decimals="4"
      id="footnoteUSY-I-ISY-I-PROS000057365AAR_A_IndexIXWWZ"
      unitRef="pure">0.0915</rr:AverageAnnualReturnSinceInception>
    <rr:AnnualReturnInceptionDate contextRef="S000057365USY-I-ISY-I-PRO">2017-05-09</rr:AnnualReturnInceptionDate>
    <rr:PerformanceTableMarketIndexChanged contextRef="S000057365USY-I-ISY-I-PRO">
   Effective April 1, 2022, the fund began comparing its performance to the MSCI ACWI (All Country World Index) ex USA ESG Leaders Index (net), which is adjusted for tax withholding rates applicable to U.S. based funds, rather than the MSCI ACWI (All Country World Index) ex USA ESG Leaders Index (gross).
   &#160;
  </rr:PerformanceTableMarketIndexChanged>
    <rr:RiskReturnHeading contextRef="S000057366USY-I-ISY-I-PRO">
   Fund Summary

    Fund:



     Fidelity&#xae; U.S. Sustainability Index Fund



  </rr:RiskReturnHeading>
    <rr:ObjectiveHeading contextRef="S000057366USY-I-ISY-I-PRO">
   Investment Objective
  </rr:ObjectiveHeading>
    <rr:ObjectivePrimaryTextBlock contextRef="S000057366USY-I-ISY-I-PRO">
   Fidelity&#xae; U.S. Sustainability Index Fund seeks to provide investment results that correspond to the total return of the MSCI USA ESG Leaders Index.
  </rr:ObjectivePrimaryTextBlock>
    <rr:ExpenseHeading contextRef="S000057366USY-I-ISY-I-PRO">
   Fee Table
  </rr:ExpenseHeading>
    <rr:ExpenseNarrativeTextBlock contextRef="S000057366USY-I-ISY-I-PRO">

    The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund.
    In addition to the fees and expenses described below, your broker may also require you to pay brokerage commissions on purchases and sales of the fund.


  </rr:ExpenseNarrativeTextBlock>
    <rr:ShareholderFeesCaption contextRef="S000057366USY-I-ISY-I-PRO">
   Shareholder fees
  </rr:ShareholderFeesCaption>
    <rr:ShareholderFeeOther
      contextRef="S000057366USY-I-ISY-I-PRO"
      decimals="0"
      unitRef="usd">0</rr:ShareholderFeeOther>
    <rr:OperatingExpensesCaption contextRef="S000057366USY-I-ISY-I-PRO">
   Annual Operating Expenses
  </rr:OperatingExpensesCaption>
    <rr:ManagementFeesOverAssets
      contextRef="S000057366C000183136"
      decimals="6"
      unitRef="pure">0.0011</rr:ManagementFeesOverAssets>
    <rr:DistributionAndService12b1FeesOverAssets
      contextRef="S000057366C000183136"
      decimals="6"
      unitRef="pure">0</rr:DistributionAndService12b1FeesOverAssets>
    <rr:OtherExpensesOverAssets
      contextRef="S000057366C000183136"
      decimals="6"
      unitRef="pure">0.0000</rr:OtherExpensesOverAssets>
    <rr:ExpensesOverAssets
      contextRef="S000057366C000183136"
      decimals="6"
      unitRef="pure">0.0011</rr:ExpensesOverAssets>
    <rr:ExpenseExampleNarrativeTextBlock contextRef="S000057366USY-I-ISY-I-PRO">
   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:
  </rr:ExpenseExampleNarrativeTextBlock>
    <rr:ExpenseExampleYear01
      contextRef="S000057366C000183136"
      decimals="0"
      unitRef="usd">11</rr:ExpenseExampleYear01>
    <rr:ExpenseExampleYear03
      contextRef="S000057366C000183136"
      decimals="0"
      unitRef="usd">35</rr:ExpenseExampleYear03>
    <rr:ExpenseExampleYear05
      contextRef="S000057366C000183136"
      decimals="0"
      unitRef="usd">62</rr:ExpenseExampleYear05>
    <rr:ExpenseExampleYear10
      contextRef="S000057366C000183136"
      decimals="0"
      unitRef="usd">141</rr:ExpenseExampleYear10>
    <rr:PortfolioTurnoverHeading contextRef="S000057366USY-I-ISY-I-PRO">
    Portfolio Turnover
   </rr:PortfolioTurnoverHeading>
    <rr:PortfolioTurnoverTextBlock contextRef="S000057366USY-I-ISY-I-PRO">
    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

      9

    % of the average value of its portfolio.
   </rr:PortfolioTurnoverTextBlock>
    <rr:PortfolioTurnoverRate
      contextRef="S000057366USY-I-ISY-I-PRO"
      decimals="4"
      unitRef="pure">0.09</rr:PortfolioTurnoverRate>
    <rr:StrategyHeading contextRef="S000057366USY-I-ISY-I-PRO">
    Principal Investment Strategies
   </rr:StrategyHeading>
    <rr:StrategyNarrativeTextBlock contextRef="S000057366USY-I-ISY-I-PRO">

     Normally investing at least 80% of assets in securities included in the MSCI USA ESG Leaders Index, which represents the performance of stocks of large- to mid-capitalization U.S. companies with high environmental, social, and governance (ESG) performance relative to their sector peers, as rated by MSCI ESG Research.
     Using statistical sampling techniques based on such factors as capitalization, industry exposures, dividend yield, price/earnings (P/E) ratio, price/book (P/B) ratio, and earnings growth to attempt to replicate the returns of the MSCI USA ESG Leaders Index.
     Lending securities to earn income for the fund.


   </rr:StrategyNarrativeTextBlock>
    <rr:RiskHeading contextRef="S000057366USY-I-ISY-I-PRO">
    Principal Investment Risks
   </rr:RiskHeading>
    <rr:RiskNarrativeTextBlock contextRef="S000057366USY-I-ISY-I-PRO">

     Stock Market Volatility.


     Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.


     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.


     Changes in the financial condition of an issuer or counterparty (e.g., broker-dealer or other borrower in a securities lending transaction) can increase the risk of default by an issuer or counterparty, which can affect a security's or instrument's value or result in delays in recovering securities and/or capital from a counterparty.


     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.


     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.


     Mid Cap Investing.


     The value of securities of medium size, less well-known issuers can perform differently from the market as a whole and other types of stocks and can be more volatile than that of larger issuers.


     Securities Lending Risk.


     Securities lending involves the risk that the borrower may fail to return the securities loaned in a timely manner or at all. If the borrower defaults on its obligation to return the securities loaned because of insolvency or other reasons, a fund could experience delays and costs in recovering the securities loaned or in gaining access to the collateral.



      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
      .


      &#160;
      You could lose money by investing in the fund.



   </rr:RiskNarrativeTextBlock>
    <rr:RiskNotInsuredDepositoryInstitution contextRef="S000057366USY-I-ISY-I-PRO">
      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
      .
     </rr:RiskNotInsuredDepositoryInstitution>
    <rr:RiskLoseMoney contextRef="S000057366USY-I-ISY-I-PRO">
      &#160;
      You could lose money by investing in the fund.
     </rr:RiskLoseMoney>
    <rr:BarChartAndPerformanceTableHeading contextRef="S000057366USY-I-ISY-I-PRO">
    Performance
   </rr:BarChartAndPerformanceTableHeading>
    <rr:PerformanceNarrativeTextBlock contextRef="S000057366USY-I-ISY-I-PRO">

     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.


   </rr:PerformanceNarrativeTextBlock>
    <rr:PerformanceInformationIllustratesVariabilityOfReturns contextRef="S000057366USY-I-ISY-I-PRO">
      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.
     </rr:PerformanceInformationIllustratesVariabilityOfReturns>
    <rr:PerformancePastDoesNotIndicateFuture contextRef="S000057366USY-I-ISY-I-PRO">
       Past performance (before and after taxes) is not an indication of future performance.
     </rr:PerformancePastDoesNotIndicateFuture>
    <rr:PerformanceAvailabilityWebSiteAddress contextRef="S000057366USY-I-ISY-I-PRO">
       www.fidelity.com
     </rr:PerformanceAvailabilityWebSiteAddress>
    <rr:BarChartHeading contextRef="S000057366USY-I-ISY-I-PRO">
    Year-by-Year Returns
   </rr:BarChartHeading>
    <rr:AnnualReturn2018
      contextRef="S000057366C000183136"
      decimals="INF"
      unitRef="pure">-0.0328</rr:AnnualReturn2018>
    <rr:AnnualReturn2019
      contextRef="S000057366C000183136"
      decimals="INF"
      unitRef="pure">0.3153</rr:AnnualReturn2019>
    <rr:AnnualReturn2020
      contextRef="S000057366C000183136"
      decimals="INF"
      unitRef="pure">0.1867</rr:AnnualReturn2020>
    <rr:AnnualReturn2021
      contextRef="S000057366C000183136"
      decimals="INF"
      unitRef="pure">0.3157</rr:AnnualReturn2021>
    <rr:HighestQuarterlyReturnLabel contextRef="S000057366USY-I-ISY-I-PRO">
        &#160;&#160;&#160;Highest Quarter Return
      </rr:HighestQuarterlyReturnLabel>
    <rr:BarChartHighestQuarterlyReturn
      contextRef="S000057366USY-I-ISY-I-PRO"
      decimals="4"
      unitRef="pure">0.2035</rr:BarChartHighestQuarterlyReturn>
    <rr:BarChartHighestQuarterlyReturnDate contextRef="S000057366USY-I-ISY-I-PRO">2020-06-30</rr:BarChartHighestQuarterlyReturnDate>
    <rr:LowestQuarterlyReturnLabel contextRef="S000057366USY-I-ISY-I-PRO">
        &#160;&#160;&#160;Lowest Quarter Return
      </rr:LowestQuarterlyReturnLabel>
    <rr:BarChartLowestQuarterlyReturn
      contextRef="S000057366USY-I-ISY-I-PRO"
      decimals="4"
      unitRef="pure">-0.1847</rr:BarChartLowestQuarterlyReturn>
    <rr:BarChartLowestQuarterlyReturnDate contextRef="S000057366USY-I-ISY-I-PRO">2020-03-31</rr:BarChartLowestQuarterlyReturnDate>
    <rr:YearToDateReturnLabel contextRef="S000057366USY-I-ISY-I-PRO">
        &#160;&#160;&#160;Year-to-Date Return
      </rr:YearToDateReturnLabel>
    <rr:BarChartYearToDateReturn
      contextRef="S000057366USY-I-ISY-I-PRO"
      decimals="4"
      unitRef="pure">-0.2594</rr:BarChartYearToDateReturn>
    <rr:BarChartYearToDateReturnDate contextRef="S000057366USY-I-ISY-I-PRO">2022-09-30</rr:BarChartYearToDateReturnDate>
    <rr:PerformanceTableHeading contextRef="S000057366USY-I-ISY-I-PRO">
    Average Annual Returns
   </rr:PerformanceTableHeading>
    <rr:PerformanceTableNarrativeTextBlock contextRef="S000057366USY-I-ISY-I-PRO">

     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.

   </rr:PerformanceTableNarrativeTextBlock>
    <rr:PerformanceTableUsesHighestFederalRate contextRef="S000057366USY-I-ISY-I-PRO">
     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.
    </rr:PerformanceTableUsesHighestFederalRate>
    <rr:PerformanceTableNotRelevantToTaxDeferred contextRef="S000057366USY-I-ISY-I-PRO">
      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).
    </rr:PerformanceTableNotRelevantToTaxDeferred>
    <rr:PerformanceTableExplanationAfterTaxHigher contextRef="S000057366USY-I-ISY-I-PRO">
      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.
    </rr:PerformanceTableExplanationAfterTaxHigher>
    <rr:AverageAnnualReturnLabel contextRef="S000057366C000183136ReturnBeforeTaxes">
       Return Before Taxes
      </rr:AverageAnnualReturnLabel>
    <rr:AverageAnnualReturnYear01
      contextRef="S000057366C000183136ReturnBeforeTaxes"
      decimals="4"
      unitRef="pure">0.3157</rr:AverageAnnualReturnYear01>
    <rr:AverageAnnualReturnSinceInception
      contextRef="S000057366C000183136ReturnBeforeTaxes"
      decimals="4"
      id="footnoteUSY-I-ISY-I-PROS000057366AAR__RBT"
      unitRef="pure">0.1901</rr:AverageAnnualReturnSinceInception>
    <rr:AverageAnnualReturnLabel contextRef="S000057366C000183136AfterTaxesOnDistributions">
       Return After Taxes on Distributions
      </rr:AverageAnnualReturnLabel>
    <rr:AverageAnnualReturnYear01
      contextRef="S000057366C000183136AfterTaxesOnDistributions"
      decimals="4"
      unitRef="pure">0.3124</rr:AverageAnnualReturnYear01>
    <rr:AverageAnnualReturnSinceInception
      contextRef="S000057366C000183136AfterTaxesOnDistributions"
      decimals="4"
      id="footnoteUSY-I-ISY-I-PROS000057366AAR__ATD"
      unitRef="pure">0.1865</rr:AverageAnnualReturnSinceInception>
    <rr:AverageAnnualReturnLabel contextRef="S000057366C000183136AfterTaxesOnDistributionsAndSales">
       Return After Taxes on Distributions and Sale of Fund Shares
      </rr:AverageAnnualReturnLabel>
    <rr:AverageAnnualReturnYear01
      contextRef="S000057366C000183136AfterTaxesOnDistributionsAndSales"
      decimals="4"
      unitRef="pure">0.1889</rr:AverageAnnualReturnYear01>
    <rr:AverageAnnualReturnSinceInception
      contextRef="S000057366C000183136AfterTaxesOnDistributionsAndSales"
      decimals="4"
      id="footnoteUSY-I-ISY-I-PROS000057366AAR__ATDS"
      unitRef="pure">0.1533</rr:AverageAnnualReturnSinceInception>
    <rr:AverageAnnualReturnLabel contextRef="S000057366IndexIXZFHUSY-I-ISY-I-PRO">
       MSCI USA ESG Leaders Index
      </rr:AverageAnnualReturnLabel>
    <rr:AverageAnnualReturnYear01
      contextRef="S000057366IndexIXZFHUSY-I-ISY-I-PRO"
      decimals="4"
      unitRef="pure">0.3173</rr:AverageAnnualReturnYear01>
    <rr:AverageAnnualReturnSinceInception
      contextRef="S000057366IndexIXZFHUSY-I-ISY-I-PRO"
      decimals="4"
      id="footnoteUSY-I-ISY-I-PROS000057366AAR_A_IndexIXZFH"
      unitRef="pure">0.1916</rr:AverageAnnualReturnSinceInception>
    <rr:AnnualReturnInceptionDate contextRef="S000057366USY-I-ISY-I-PRO">2017-05-09</rr:AnnualReturnInceptionDate>
    <rr:RiskReturnHeading contextRef="S000054097TI1-I-PRO">
  Fund Summary

   Fund:



    Fidelity&#xae; Total International Index Fund



 </rr:RiskReturnHeading>
    <rr:ObjectiveHeading contextRef="S000054097TI1-I-PRO">
  Investment Objective
 </rr:ObjectiveHeading>
    <rr:ObjectivePrimaryTextBlock contextRef="S000054097TI1-I-PRO">
  Fidelity&#xae; Total International Index Fund seeks to provide investment results that correspond to the total return of foreign developed and emerging stock markets.
 </rr:ObjectivePrimaryTextBlock>
    <rr:ExpenseHeading contextRef="S000054097TI1-I-PRO">
  Fee Table
 </rr:ExpenseHeading>
    <rr:ExpenseNarrativeTextBlock contextRef="S000054097TI1-I-PRO">

   The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund.
   In addition to the fees and expenses described below, your broker may also require you to pay brokerage commissions on purchases and sales of the fund.


 </rr:ExpenseNarrativeTextBlock>
    <rr:ShareholderFeesCaption contextRef="S000054097TI1-I-PRO">
  Shareholder fees
 </rr:ShareholderFeesCaption>
    <rr:ShareholderFeeOther contextRef="S000054097TI1-I-PRO" decimals="0" unitRef="usd">0</rr:ShareholderFeeOther>
    <rr:OperatingExpensesCaption contextRef="S000054097TI1-I-PRO">
  Annual Operating Expenses
 </rr:OperatingExpensesCaption>
    <rr:ManagementFeesOverAssets
      contextRef="S000054097C000170041"
      decimals="6"
      unitRef="pure">0.0006</rr:ManagementFeesOverAssets>
    <rr:DistributionAndService12b1FeesOverAssets
      contextRef="S000054097C000170041"
      decimals="6"
      unitRef="pure">0</rr:DistributionAndService12b1FeesOverAssets>
    <rr:OtherExpensesOverAssets
      contextRef="S000054097C000170041"
      decimals="6"
      unitRef="pure">0.0000</rr:OtherExpensesOverAssets>
    <rr:ExpensesOverAssets
      contextRef="S000054097C000170041"
      decimals="6"
      unitRef="pure">0.0006</rr:ExpensesOverAssets>
    <rr:ExpenseExampleNarrativeTextBlock contextRef="S000054097TI1-I-PRO">
  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:
 </rr:ExpenseExampleNarrativeTextBlock>
    <rr:ExpenseExampleYear01
      contextRef="S000054097C000170041"
      decimals="0"
      unitRef="usd">6</rr:ExpenseExampleYear01>
    <rr:ExpenseExampleYear03
      contextRef="S000054097C000170041"
      decimals="0"
      unitRef="usd">19</rr:ExpenseExampleYear03>
    <rr:ExpenseExampleYear05
      contextRef="S000054097C000170041"
      decimals="0"
      unitRef="usd">34</rr:ExpenseExampleYear05>
    <rr:ExpenseExampleYear10
      contextRef="S000054097C000170041"
      decimals="0"
      unitRef="usd">77</rr:ExpenseExampleYear10>
    <rr:PortfolioTurnoverHeading contextRef="S000054097TI1-I-PRO">
   Portfolio Turnover
  </rr:PortfolioTurnoverHeading>
    <rr:PortfolioTurnoverTextBlock contextRef="S000054097TI1-I-PRO">
   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

     3

   % of the average value of its portfolio.
  </rr:PortfolioTurnoverTextBlock>
    <rr:PortfolioTurnoverRate
      contextRef="S000054097TI1-I-PRO"
      decimals="4"
      unitRef="pure">0.03</rr:PortfolioTurnoverRate>
    <rr:StrategyHeading contextRef="S000054097TI1-I-PRO">
   Principal Investment Strategies
  </rr:StrategyHeading>
    <rr:StrategyNarrativeTextBlock contextRef="S000054097TI1-I-PRO">

    Normally investing at least 80% of assets in securities included in the MSCI ACWI (All Country World Index) ex USA Investable Market Index and in depositary receipts representing securities included in the index. The MSCI ACWI (All Country World Index) ex USA Investable Market Index is a market capitalization-weighted index designed to measure the investable equity market performance for global investors of large, mid, and small-cap stocks in developed and emerging markets, excluding the U.S.
    Using statistical sampling techniques based on such factors as capitalization, industry exposures, dividend yield, price/earnings (P/E) ratio, price/book (P/B) ratio, earnings growth, country weightings, and the effect of foreign taxes to attempt to replicate the returns of the MSCI ACWI (All Country World Index) ex USA Investable Market Index.
    Lending securities to earn income for the fund.


  </rr:StrategyNarrativeTextBlock>
    <rr:RiskHeading contextRef="S000054097TI1-I-PRO">
   Principal Investment Risks
  </rr:RiskHeading>
    <rr:RiskNarrativeTextBlock contextRef="S000054097TI1-I-PRO">

    Stock Market Volatility.


    Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.


    Foreign and Emerging Markets Risk.


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


    The extent of economic development; political stability; market depth, infrastructure, and capitalization; and regulatory oversight can be less than in more developed markets. Emerging markets typically have less established legal, accounting and financial reporting systems than those in more developed markets, which may reduce the scope or quality of financial information available to investors.


    Emerging markets can be subject to greater social, economic, regulatory, and political uncertainties and can be extremely volatile.


    Foreign exchange rates also can be extremely volatile.


    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.


    Changes in the financial condition of an issuer or counterparty (e.g., broker-dealer or other borrower in a securities lending transaction) can increase the risk of default by an issuer or counterparty, which can affect a security's or instrument's value or result in delays in recovering securities and/or capital from a counterparty.


    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.


    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.


    Mid Cap Investing.


    The value of securities of medium size, less well-known issuers can perform differently from the market as a whole and other types of stocks and can be more volatile than that of larger issuers.


    Small Cap Investing.


    The value of securities of smaller, less well-known issuers can perform differently from the market as a whole and other types of stocks and can be more volatile than that of larger issuers.


    Securities Lending Risk.


    Securities lending involves the risk that the borrower may fail to return the securities loaned in a timely manner or at all. If the borrower defaults on its obligation to return the securities loaned because of insolvency or other reasons, a fund could experience delays and costs in recovering the securities loaned or in gaining access to the collateral.



     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
     .


     &#160;
     You could lose money by investing in the fund.



  </rr:RiskNarrativeTextBlock>
    <rr:RiskNotInsuredDepositoryInstitution contextRef="S000054097TI1-I-PRO">
     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
     .
    </rr:RiskNotInsuredDepositoryInstitution>
    <rr:RiskLoseMoney contextRef="S000054097TI1-I-PRO">
     &#160;
     You could lose money by investing in the fund.
    </rr:RiskLoseMoney>
    <rr:BarChartAndPerformanceTableHeading contextRef="S000054097TI1-I-PRO">
   Performance
  </rr:BarChartAndPerformanceTableHeading>
    <rr:PerformanceNarrativeTextBlock contextRef="S000054097TI1-I-PRO">

    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.


  </rr:PerformanceNarrativeTextBlock>
    <rr:PerformanceInformationIllustratesVariabilityOfReturns contextRef="S000054097TI1-I-PRO">
     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.
    </rr:PerformanceInformationIllustratesVariabilityOfReturns>
    <rr:PerformancePastDoesNotIndicateFuture contextRef="S000054097TI1-I-PRO">
      Past performance (before and after taxes) is not an indication of future performance.
    </rr:PerformancePastDoesNotIndicateFuture>
    <rr:PerformanceAvailabilityWebSiteAddress contextRef="S000054097TI1-I-PRO">
      www.fidelity.com
    </rr:PerformanceAvailabilityWebSiteAddress>
    <rr:BarChartHeading contextRef="S000054097TI1-I-PRO">
   Year-by-Year Returns
  </rr:BarChartHeading>
    <rr:AnnualReturn2017
      contextRef="S000054097C000170041"
      decimals="INF"
      unitRef="pure">0.2763</rr:AnnualReturn2017>
    <rr:AnnualReturn2018
      contextRef="S000054097C000170041"
      decimals="INF"
      unitRef="pure">-0.1438</rr:AnnualReturn2018>
    <rr:AnnualReturn2019
      contextRef="S000054097C000170041"
      decimals="INF"
      unitRef="pure">0.2148</rr:AnnualReturn2019>
    <rr:AnnualReturn2020
      contextRef="S000054097C000170041"
      decimals="INF"
      unitRef="pure">0.1107</rr:AnnualReturn2020>
    <rr:AnnualReturn2021
      contextRef="S000054097C000170041"
      decimals="INF"
      unitRef="pure">0.0847</rr:AnnualReturn2021>
    <rr:HighestQuarterlyReturnLabel contextRef="S000054097TI1-I-PRO">
       &#160;&#160;&#160;Highest Quarter Return
     </rr:HighestQuarterlyReturnLabel>
    <rr:BarChartHighestQuarterlyReturn
      contextRef="S000054097TI1-I-PRO"
      decimals="4"
      unitRef="pure">0.1741</rr:BarChartHighestQuarterlyReturn>
    <rr:BarChartHighestQuarterlyReturnDate contextRef="S000054097TI1-I-PRO">2020-06-30</rr:BarChartHighestQuarterlyReturnDate>
    <rr:LowestQuarterlyReturnLabel contextRef="S000054097TI1-I-PRO">
       &#160;&#160;&#160;Lowest Quarter Return
     </rr:LowestQuarterlyReturnLabel>
    <rr:BarChartLowestQuarterlyReturn
      contextRef="S000054097TI1-I-PRO"
      decimals="4"
      unitRef="pure">-0.2415</rr:BarChartLowestQuarterlyReturn>
    <rr:BarChartLowestQuarterlyReturnDate contextRef="S000054097TI1-I-PRO">2020-03-31</rr:BarChartLowestQuarterlyReturnDate>
    <rr:YearToDateReturnLabel contextRef="S000054097TI1-I-PRO">
       &#160;&#160;&#160;Year-to-Date Return
     </rr:YearToDateReturnLabel>
    <rr:BarChartYearToDateReturn
      contextRef="S000054097TI1-I-PRO"
      decimals="4"
      unitRef="pure">-0.2706</rr:BarChartYearToDateReturn>
    <rr:BarChartYearToDateReturnDate contextRef="S000054097TI1-I-PRO">2022-09-30</rr:BarChartYearToDateReturnDate>
    <rr:PerformanceTableHeading contextRef="S000054097TI1-I-PRO">
   Average Annual Returns
  </rr:PerformanceTableHeading>
    <rr:PerformanceTableNarrativeTextBlock contextRef="S000054097TI1-I-PRO">

    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.

  </rr:PerformanceTableNarrativeTextBlock>
    <rr:PerformanceTableUsesHighestFederalRate contextRef="S000054097TI1-I-PRO">
    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.
   </rr:PerformanceTableUsesHighestFederalRate>
    <rr:PerformanceTableNotRelevantToTaxDeferred contextRef="S000054097TI1-I-PRO">
     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).
   </rr:PerformanceTableNotRelevantToTaxDeferred>
    <rr:PerformanceTableExplanationAfterTaxHigher contextRef="S000054097TI1-I-PRO">
     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.
   </rr:PerformanceTableExplanationAfterTaxHigher>
    <rr:AverageAnnualReturnLabel contextRef="S000054097C000170041ReturnBeforeTaxes">
      Return Before Taxes
     </rr:AverageAnnualReturnLabel>
    <rr:AverageAnnualReturnYear01
      contextRef="S000054097C000170041ReturnBeforeTaxes"
      decimals="4"
      unitRef="pure">0.0847</rr:AverageAnnualReturnYear01>
    <rr:AverageAnnualReturnYear05
      contextRef="S000054097C000170041ReturnBeforeTaxes"
      decimals="4"
      unitRef="pure">0.0985</rr:AverageAnnualReturnYear05>
    <rr:AverageAnnualReturnSinceInception
      contextRef="S000054097C000170041ReturnBeforeTaxes"
      decimals="4"
      id="footnoteTI1-I-PROS000054097AAR__RBT"
      unitRef="pure">0.0889</rr:AverageAnnualReturnSinceInception>
    <rr:AverageAnnualReturnLabel contextRef="S000054097C000170041AfterTaxesOnDistributions">
      Return After Taxes on Distributions
     </rr:AverageAnnualReturnLabel>
    <rr:AverageAnnualReturnYear01
      contextRef="S000054097C000170041AfterTaxesOnDistributions"
      decimals="4"
      unitRef="pure">0.0786</rr:AverageAnnualReturnYear01>
    <rr:AverageAnnualReturnYear05
      contextRef="S000054097C000170041AfterTaxesOnDistributions"
      decimals="4"
      unitRef="pure">0.0935</rr:AverageAnnualReturnYear05>
    <rr:AverageAnnualReturnSinceInception
      contextRef="S000054097C000170041AfterTaxesOnDistributions"
      decimals="4"
      id="footnoteTI1-I-PROS000054097AAR__ATD"
      unitRef="pure">0.0842</rr:AverageAnnualReturnSinceInception>
    <rr:AverageAnnualReturnLabel contextRef="S000054097C000170041AfterTaxesOnDistributionsAndSales">
      Return After Taxes on Distributions and Sale of Fund Shares
     </rr:AverageAnnualReturnLabel>
    <rr:AverageAnnualReturnYear01
      contextRef="S000054097C000170041AfterTaxesOnDistributionsAndSales"
      decimals="4"
      unitRef="pure">0.0551</rr:AverageAnnualReturnYear01>
    <rr:AverageAnnualReturnYear05
      contextRef="S000054097C000170041AfterTaxesOnDistributionsAndSales"
      decimals="4"
      unitRef="pure">0.0780</rr:AverageAnnualReturnYear05>
    <rr:AverageAnnualReturnSinceInception
      contextRef="S000054097C000170041AfterTaxesOnDistributionsAndSales"
      decimals="4"
      id="footnoteTI1-I-PROS000054097AAR__ATDS"
      unitRef="pure">0.0704</rr:AverageAnnualReturnSinceInception>
    <rr:AverageAnnualReturnLabel contextRef="S000054097IndexIX425TI1-I-PRO">
      MSCI ACWI (All Country World Index) ex USA Investable Market Index
     </rr:AverageAnnualReturnLabel>
    <rr:AverageAnnualReturnYear01
      contextRef="S000054097IndexIX425TI1-I-PRO"
      decimals="4"
      unitRef="pure">0.0868</rr:AverageAnnualReturnYear01>
    <rr:AverageAnnualReturnYear05
      contextRef="S000054097IndexIX425TI1-I-PRO"
      decimals="4"
      unitRef="pure">0.1001</rr:AverageAnnualReturnYear05>
    <rr:AverageAnnualReturnSinceInception
      contextRef="S000054097IndexIX425TI1-I-PRO"
      decimals="4"
      id="footnoteTI1-I-PROS000054097AAR_A_IndexIX425"
      unitRef="pure">0.0920</rr:AverageAnnualReturnSinceInception>
    <rr:AnnualReturnInceptionDate contextRef="S000054097TI1-I-PRO">2016-06-07</rr:AnnualReturnInceptionDate>
    <rr:RiskReturnHeading contextRef="S000026422SGX-PRO">
  Fund Summary

   Fund:



    Fidelity&#xae; Series Global ex U.S. Index Fund



 </rr:RiskReturnHeading>
    <rr:ObjectiveHeading contextRef="S000026422SGX-PRO">
  Investment Objective
 </rr:ObjectiveHeading>
    <rr:ObjectivePrimaryTextBlock contextRef="S000026422SGX-PRO">
  Fidelity&#xae; Series Global ex U.S. Index Fund seeks to provide investment results that correspond to the total return of foreign developed and emerging stock markets.
 </rr:ObjectivePrimaryTextBlock>
    <rr:ExpenseHeading contextRef="S000026422SGX-PRO">
  Fee Table
 </rr:ExpenseHeading>
    <rr:ExpenseNarrativeTextBlock contextRef="S000026422SGX-PRO">

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


 </rr:ExpenseNarrativeTextBlock>
    <rr:ShareholderFeesCaption contextRef="S000026422SGX-PRO">
  Shareholder fees
 </rr:ShareholderFeesCaption>
    <rr:ShareholderFeeOther contextRef="S000026422SGX-PRO" decimals="0" unitRef="usd">0</rr:ShareholderFeeOther>
    <rr:OperatingExpensesCaption contextRef="S000026422SGX-PRO">
  Annual Operating Expenses
 </rr:OperatingExpensesCaption>
    <rr:ManagementFeesOverAssets
      contextRef="S000026422C000079292"
      decimals="6"
      unitRef="pure">0</rr:ManagementFeesOverAssets>
    <rr:DistributionAndService12b1FeesOverAssets
      contextRef="S000026422C000079292"
      decimals="6"
      unitRef="pure">0</rr:DistributionAndService12b1FeesOverAssets>
    <rr:OtherExpensesOverAssets
      contextRef="S000026422C000079292"
      decimals="6"
      unitRef="pure">0.0002</rr:OtherExpensesOverAssets>
    <rr:ExpensesOverAssets
      contextRef="S000026422C000079292"
      decimals="6"
      unitRef="pure">0.0002</rr:ExpensesOverAssets>
    <rr:FeeWaiverOrReimbursementOverAssets
      contextRef="S000026422C000079292"
      decimals="6"
      id="footnoteSGX-PROAOE_A_FW"
      unitRef="pure">-0.0001</rr:FeeWaiverOrReimbursementOverAssets>
    <rr:NetExpensesOverAssets
      contextRef="S000026422C000079292"
      decimals="6"
      unitRef="pure">0.0001</rr:NetExpensesOverAssets>
    <rr:FeeWaiverOrReimbursementOverAssetsDateOfTermination contextRef="S000026422SGX-PRO">
   February 28, 2026
  </rr:FeeWaiverOrReimbursementOverAssetsDateOfTermination>
    <rr:ExpenseExampleNarrativeTextBlock contextRef="S000026422SGX-PRO">
  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:
 </rr:ExpenseExampleNarrativeTextBlock>
    <rr:ExpenseExampleYear01
      contextRef="S000026422C000079292"
      decimals="0"
      unitRef="usd">1</rr:ExpenseExampleYear01>
    <rr:ExpenseExampleYear03
      contextRef="S000026422C000079292"
      decimals="0"
      unitRef="usd">4</rr:ExpenseExampleYear03>
    <rr:ExpenseExampleYear05
      contextRef="S000026422C000079292"
      decimals="0"
      unitRef="usd">9</rr:ExpenseExampleYear05>
    <rr:ExpenseExampleYear10
      contextRef="S000026422C000079292"
      decimals="0"
      unitRef="usd">23</rr:ExpenseExampleYear10>
    <rr:PortfolioTurnoverHeading contextRef="S000026422SGX-PRO">
   Portfolio Turnover
  </rr:PortfolioTurnoverHeading>
    <rr:PortfolioTurnoverTextBlock contextRef="S000026422SGX-PRO">
   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

     4

   % of the average value of its portfolio.
  </rr:PortfolioTurnoverTextBlock>
    <rr:PortfolioTurnoverRate contextRef="S000026422SGX-PRO" decimals="4" unitRef="pure">0.04</rr:PortfolioTurnoverRate>
    <rr:StrategyHeading contextRef="S000026422SGX-PRO">
   Principal Investment Strategies
  </rr:StrategyHeading>
    <rr:StrategyNarrativeTextBlock contextRef="S000026422SGX-PRO">

    Normally investing at least 80% of assets in securities included in the MSCI ACWI (All Country World Index) ex USA Index and in depositary receipts representing securities included in the index.
    Lending securities to earn income for the fund.
    Using statistical sampling techniques based on such factors as capitalization, industry exposures, dividend yield, price/earnings (P/E) ratio, price/book (P/B) ratio, earnings growth, country weightings, and the effect of foreign taxes to attempt to replicate the returns of the MSCI ACWI (All Country World Index) ex USA Index.


  </rr:StrategyNarrativeTextBlock>
    <rr:RiskHeading contextRef="S000026422SGX-PRO">
   Principal Investment Risks
  </rr:RiskHeading>
    <rr:RiskNarrativeTextBlock contextRef="S000026422SGX-PRO">

    Stock Market Volatility.


    Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.


    Foreign and Emerging Markets Risk.


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


    The extent of economic development; political stability; market depth, infrastructure, and capitalization; and regulatory oversight can be less than in more developed markets. Emerging markets typically have less established legal, accounting and financial reporting systems than those in more developed markets, which may reduce the scope or quality of financial information available to investors.


    Emerging markets can be subject to greater social, economic, regulatory, and political uncertainties and can be extremely volatile.


    Foreign exchange rates also can be extremely volatile.


    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.


    Changes in the financial condition of an issuer or counterparty (e.g., broker-dealer or other borrower in a securities lending transaction) can increase the risk of default by an issuer or counterparty, which can affect a security's or instrument's value or result in delays in recovering securities and/or capital from a counterparty.


    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.


    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.


    Securities Lending Risk.


    Securities lending involves the risk that the borrower may fail to return the securities loaned in a timely manner or at all. If the borrower defaults on its obligation to return the securities loaned because of insolvency or other reasons, a fund could experience delays and costs in recovering the securities loaned or in gaining access to the collateral.



     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
     .


     &#160;
     You could lose money by investing in the fund.



  </rr:RiskNarrativeTextBlock>
    <rr:RiskNotInsuredDepositoryInstitution contextRef="S000026422SGX-PRO">
     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
     .
    </rr:RiskNotInsuredDepositoryInstitution>
    <rr:RiskLoseMoney contextRef="S000026422SGX-PRO">
     &#160;
     You could lose money by investing in the fund.
    </rr:RiskLoseMoney>
    <rr:BarChartAndPerformanceTableHeading contextRef="S000026422SGX-PRO">
   Performance
  </rr:BarChartAndPerformanceTableHeading>
    <rr:PerformanceNarrativeTextBlock contextRef="S000026422SGX-PRO">

    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 for more recent performance information.


  </rr:PerformanceNarrativeTextBlock>
    <rr:PerformanceInformationIllustratesVariabilityOfReturns contextRef="S000026422SGX-PRO">
     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.
    </rr:PerformanceInformationIllustratesVariabilityOfReturns>
    <rr:PerformancePastDoesNotIndicateFuture contextRef="S000026422SGX-PRO">
      Past performance (before and after taxes) is not an indication of future performance.
    </rr:PerformancePastDoesNotIndicateFuture>
    <rr:PerformanceAvailabilityWebSiteAddress contextRef="S000026422SGX-PRO">
      www.401k.com
    </rr:PerformanceAvailabilityWebSiteAddress>
    <rr:BarChartHeading contextRef="S000026422SGX-PRO">
   Year-by-Year Returns
  </rr:BarChartHeading>
    <rr:AnnualReturn2012
      contextRef="S000026422C000079292"
      decimals="INF"
      unitRef="pure">0.1802</rr:AnnualReturn2012>
    <rr:AnnualReturn2013
      contextRef="S000026422C000079292"
      decimals="INF"
      unitRef="pure">0.1422</rr:AnnualReturn2013>
    <rr:AnnualReturn2014
      contextRef="S000026422C000079292"
      decimals="INF"
      unitRef="pure">-0.0438</rr:AnnualReturn2014>
    <rr:AnnualReturn2015
      contextRef="S000026422C000079292"
      decimals="INF"
      unitRef="pure">-0.0575</rr:AnnualReturn2015>
    <rr:AnnualReturn2016
      contextRef="S000026422C000079292"
      decimals="INF"
      unitRef="pure">0.0464</rr:AnnualReturn2016>
    <rr:AnnualReturn2017
      contextRef="S000026422C000079292"
      decimals="INF"
      unitRef="pure">0.2747</rr:AnnualReturn2017>
    <rr:AnnualReturn2018
      contextRef="S000026422C000079292"
      decimals="INF"
      unitRef="pure">-0.1395</rr:AnnualReturn2018>
    <rr:AnnualReturn2019
      contextRef="S000026422C000079292"
      decimals="INF"
      unitRef="pure">0.2139</rr:AnnualReturn2019>
    <rr:AnnualReturn2020
      contextRef="S000026422C000079292"
      decimals="INF"
      unitRef="pure">0.1076</rr:AnnualReturn2020>
    <rr:AnnualReturn2021
      contextRef="S000026422C000079292"
      decimals="INF"
      unitRef="pure">0.0777</rr:AnnualReturn2021>
    <rr:HighestQuarterlyReturnLabel contextRef="S000026422SGX-PRO">
       &#160;&#160;&#160;Highest Quarter Return
     </rr:HighestQuarterlyReturnLabel>
    <rr:BarChartHighestQuarterlyReturn contextRef="S000026422SGX-PRO" decimals="4" unitRef="pure">0.1675</rr:BarChartHighestQuarterlyReturn>
    <rr:BarChartHighestQuarterlyReturnDate contextRef="S000026422SGX-PRO">2020-06-30</rr:BarChartHighestQuarterlyReturnDate>
    <rr:LowestQuarterlyReturnLabel contextRef="S000026422SGX-PRO">
       &#160;&#160;&#160;Lowest Quarter Return
     </rr:LowestQuarterlyReturnLabel>
    <rr:BarChartLowestQuarterlyReturn contextRef="S000026422SGX-PRO" decimals="4" unitRef="pure">-0.2339</rr:BarChartLowestQuarterlyReturn>
    <rr:BarChartLowestQuarterlyReturnDate contextRef="S000026422SGX-PRO">2020-03-31</rr:BarChartLowestQuarterlyReturnDate>
    <rr:YearToDateReturnLabel contextRef="S000026422SGX-PRO">
       &#160;&#160;&#160;Year-to-Date Return
     </rr:YearToDateReturnLabel>
    <rr:BarChartYearToDateReturn contextRef="S000026422SGX-PRO" decimals="4" unitRef="pure">-0.2669</rr:BarChartYearToDateReturn>
    <rr:BarChartYearToDateReturnDate contextRef="S000026422SGX-PRO">2022-09-30</rr:BarChartYearToDateReturnDate>
    <rr:PerformanceTableHeading contextRef="S000026422SGX-PRO">
   Average Annual Returns
  </rr:PerformanceTableHeading>
    <rr:PerformanceTableNarrativeTextBlock contextRef="S000026422SGX-PRO">

    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.

  </rr:PerformanceTableNarrativeTextBlock>
    <rr:PerformanceTableUsesHighestFederalRate contextRef="S000026422SGX-PRO">
    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.
   </rr:PerformanceTableUsesHighestFederalRate>
    <rr:PerformanceTableNotRelevantToTaxDeferred contextRef="S000026422SGX-PRO">
     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).
   </rr:PerformanceTableNotRelevantToTaxDeferred>
    <rr:PerformanceTableExplanationAfterTaxHigher contextRef="S000026422SGX-PRO">
     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.
   </rr:PerformanceTableExplanationAfterTaxHigher>
    <rr:AverageAnnualReturnLabel contextRef="S000026422C000079292ReturnBeforeTaxes">
      Return Before Taxes
     </rr:AverageAnnualReturnLabel>
    <rr:AverageAnnualReturnYear01
      contextRef="S000026422C000079292ReturnBeforeTaxes"
      decimals="4"
      unitRef="pure">0.0777</rr:AverageAnnualReturnYear01>
    <rr:AverageAnnualReturnYear05
      contextRef="S000026422C000079292ReturnBeforeTaxes"
      decimals="4"
      unitRef="pure">0.0971</rr:AverageAnnualReturnYear05>
    <rr:AverageAnnualReturnYear10
      contextRef="S000026422C000079292ReturnBeforeTaxes"
      decimals="4"
      unitRef="pure">0.0728</rr:AverageAnnualReturnYear10>
    <rr:AverageAnnualReturnLabel contextRef="S000026422C000079292AfterTaxesOnDistributions">
      Return After Taxes on Distributions
     </rr:AverageAnnualReturnLabel>
    <rr:AverageAnnualReturnYear01
      contextRef="S000026422C000079292AfterTaxesOnDistributions"
      decimals="4"
      unitRef="pure">0.0692</rr:AverageAnnualReturnYear01>
    <rr:AverageAnnualReturnYear05
      contextRef="S000026422C000079292AfterTaxesOnDistributions"
      decimals="4"
      unitRef="pure">0.0899</rr:AverageAnnualReturnYear05>
    <rr:AverageAnnualReturnYear10
      contextRef="S000026422C000079292AfterTaxesOnDistributions"
      decimals="4"
      unitRef="pure">0.0662</rr:AverageAnnualReturnYear10>
    <rr:AverageAnnualReturnLabel contextRef="S000026422C000079292AfterTaxesOnDistributionsAndSales">
      Return After Taxes on Distributions and Sale of Fund Shares
     </rr:AverageAnnualReturnLabel>
    <rr:AverageAnnualReturnYear01
      contextRef="S000026422C000079292AfterTaxesOnDistributionsAndSales"
      decimals="4"
      unitRef="pure">0.0487</rr:AverageAnnualReturnYear01>
    <rr:AverageAnnualReturnYear05
      contextRef="S000026422C000079292AfterTaxesOnDistributionsAndSales"
      decimals="4"
      unitRef="pure">0.0750</rr:AverageAnnualReturnYear05>
    <rr:AverageAnnualReturnYear10
      contextRef="S000026422C000079292AfterTaxesOnDistributionsAndSales"
      decimals="4"
      unitRef="pure">0.0572</rr:AverageAnnualReturnYear10>
    <rr:AverageAnnualReturnLabel contextRef="S000026422IndexMS112SGX-PRO">
      MSCI ACWI (All Country World Index) ex USA Index
     </rr:AverageAnnualReturnLabel>
    <rr:AverageAnnualReturnYear01
      contextRef="S000026422IndexMS112SGX-PRO"
      decimals="4"
      unitRef="pure">0.0798</rr:AverageAnnualReturnYear01>
    <rr:AverageAnnualReturnYear05
      contextRef="S000026422IndexMS112SGX-PRO"
      decimals="4"
      unitRef="pure">0.0979</rr:AverageAnnualReturnYear05>
    <rr:AverageAnnualReturnYear10
      contextRef="S000026422IndexMS112SGX-PRO"
      decimals="4"
      unitRef="pure">0.0744</rr:AverageAnnualReturnYear10>
    <link:footnoteLink
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        <link:footnote id="footnoteSV7-PROAOE_A" xlink:label="footnoteSV7-PROAOE_A" xlink:role="http://www.xbrl.org/2003/role/footnote" xlink:type="resource" xml:lang="en-US"><xhtml:span style="font-family:'Fidelity Futura Std Book',Arial,Helvetica,sans-serif;font-size:6px;color:#000000;font-style:normal;vertical-align:super;font-weight:normal;">A</xhtml:span><xhtml:span style="font-family:'Fidelity Futura Std Book',Arial,Helvetica,sans-serif;font-size:11px;color:#000000;font-style:normal;font-weight:normal;"><xhtml:span style="padding-right:10px"/></xhtml:span><xhtml:span style="font-family:'Fidelity Futura Std Book',Arial,Helvetica,sans-serif;font-size:11px;color:#000000;font-style:normal;font-weight:normal;">Fidelity Management &amp; Research Company LLC (FMR) has contractually agreed to reimburse the fund to the extent that total operating expenses (excluding interest, certain taxes, fees and expenses of the Independent Trustees, proxy and shareholder meeting expenses, extraordinary expenses, and acquired fund fees and expenses (including fees and expenses associated with a wholly owned subsidiary), if any, as well as non-operating expenses such as brokerage commissions and fees and expenses associated with the fund's securities lending program, if applicable), as a percentage of its average net assets, exceed 0.035% (the Expense Cap). If at any time during the current fiscal year expenses for the fund fall below the Expense Cap, FMR reserves the right to recoup through the end of the fiscal year any expenses that were reimbursed during the current fiscal year up to, but not in excess of, the Expense Cap. This arrangement will remain in effect through </xhtml:span><xhtml:span style="font-family:'Fidelity Futura Std Book',Arial,Helvetica,sans-serif;font-size:11px;color:#000000;font-style:normal;font-weight:normal;">February 29, 2024</xhtml:span><xhtml:span style="font-family:'Fidelity Futura Std Book',Arial,Helvetica,sans-serif;font-size:11px;color:#000000;font-style:normal;font-weight:normal;">. 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></link:footnote>
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        <link:footnote id="footnoteEMV-IQI-PROS000068374AAR_A" xlink:label="footnoteEMV-IQI-PROS000068374AAR_A" xlink:role="http://www.xbrl.org/2003/role/footnote" xlink:type="resource" xml:lang="en-US"><xhtml:span style="font-family:'Fidelity Futura Std Book',Arial,Helvetica,sans-serif;font-size:6px;color:#000000;font-style:normal;vertical-align:super;font-weight:normal;">A</xhtml:span><xhtml:span style="font-family:'Fidelity Futura Std Book',Arial,Helvetica,sans-serif;font-size:11px;color:#000000;font-style:italic;font-weight:normal;">From </xhtml:span><xhtml:span style="font-family:'Fidelity Futura Std Book',Arial,Helvetica,sans-serif;font-size:11px;color:#000000;font-style:italic;font-weight:normal;">May 12, 2020</xhtml:span></link:footnote>
        <link:footnoteArc
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          xlink:from="footnoteEMV-IQI-PROS000068374AAR_A_IndexIXXJI"
          xlink:to="footnoteEMV-IQI-PROS000068374AAR_A"
          xlink:type="arc"/>
        <link:loc
          xlink:href="#footnoteEMV-IQI-PROS000068375AAR_A_IndexIXXJJ"
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          xlink:type="locator"/>
        <link:footnote id="footnoteEMV-IQI-PROS000068375AAR_A" xlink:label="footnoteEMV-IQI-PROS000068375AAR_A" xlink:role="http://www.xbrl.org/2003/role/footnote" xlink:type="resource" xml:lang="en-US"><xhtml:span style="font-family:'Fidelity Futura Std Book',Arial,Helvetica,sans-serif;font-size:6px;color:#000000;font-style:normal;vertical-align:super;font-weight:normal;">A</xhtml:span><xhtml:span style="font-family:'Fidelity Futura Std Book',Arial,Helvetica,sans-serif;font-size:11px;color:#000000;font-style:italic;font-weight:normal;">From </xhtml:span><xhtml:span style="font-family:'Fidelity Futura Std Book',Arial,Helvetica,sans-serif;font-size:11px;color:#000000;font-style:italic;font-weight:normal;">May 12, 2020</xhtml:span></link:footnote>
        <link:footnoteArc
          xlink:arcrole="http://www.xbrl.org/2003/arcrole/fact-footnote"
          xlink:from="footnoteEMV-IQI-PROS000068375AAR_A_IndexIXXJJ"
          xlink:to="footnoteEMV-IQI-PROS000068375AAR_A"
          xlink:type="arc"/>
        <link:loc
          xlink:href="#footnoteSV1-SV2-PROAOE_A_FW"
          xlink:label="footnoteSV1-SV2-PROAOE_A_FW"
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        <link:footnote id="footnoteSV1-SV2-PROAOE_A" xlink:label="footnoteSV1-SV2-PROAOE_A" xlink:role="http://www.xbrl.org/2003/role/footnote" xlink:type="resource" xml:lang="en-US"><xhtml:span style="font-family:'Fidelity Futura Std Book',Arial,Helvetica,sans-serif;font-size:6px;color:#000000;font-style:normal;vertical-align:super;font-weight:normal;">A</xhtml:span><xhtml:span style="font-family:'Fidelity Futura Std Book',Arial,Helvetica,sans-serif;font-size:11px;color:#000000;font-style:normal;font-weight:normal;"><xhtml:span style="padding-right:10px"/></xhtml:span><xhtml:span style="font-family:'Fidelity Futura Std Book',Arial,Helvetica,sans-serif;font-size:11px;color:#000000;font-style:normal;font-weight:normal;">Fidelity Management &amp; Research Company LLC (FMR) has contractually agreed to reimburse the fund to the extent that total operating expenses (excluding interest, certain taxes, fees and expenses of the Independent Trustees, proxy and shareholder meeting expenses, extraordinary expenses, and acquired fund fees and expenses (including fees and expenses associated with a wholly owned subsidiary), if any, as well as non-operating expenses such as brokerage commissions and fees and expenses associated with the fund's securities lending program, if applicable), as a percentage of its average net assets, exceed 0.25% (the Expense Cap). If at any time during the current fiscal year expenses for the fund fall below the Expense Cap, FMR reserves the right to recoup through the end of the fiscal year any expenses that were reimbursed during the current fiscal year up to, but not in excess of, the Expense Cap. This arrangement will remain in effect through </xhtml:span><xhtml:span style="font-family:'Fidelity Futura Std Book',Arial,Helvetica,sans-serif;font-size:11px;color:#000000;font-style:normal;font-weight:normal;">February 29, 2024</xhtml:span><xhtml:span style="font-family:'Fidelity Futura Std Book',Arial,Helvetica,sans-serif;font-size:11px;color:#000000;font-style:normal;font-weight:normal;">. 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></link:footnote>
        <link:footnoteArc
          xlink:arcrole="http://www.xbrl.org/2003/arcrole/fact-footnote"
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        <link:loc
          xlink:href="#footnoteSV1-SV2-PROS000063743AAR_A_IndexIXYQL"
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        <link:footnote id="footnoteSV1-SV2-PROS000063743AAR_A" xlink:label="footnoteSV1-SV2-PROS000063743AAR_A" xlink:role="http://www.xbrl.org/2003/role/footnote" xlink:type="resource" xml:lang="en-US"><xhtml:span style="font-family:'Fidelity Futura Std Book',Arial,Helvetica,sans-serif;font-size:6px;color:#000000;font-style:normal;vertical-align:super;font-weight:normal;">A</xhtml:span><xhtml:span style="font-family:'Fidelity Futura Std Book',Arial,Helvetica,sans-serif;font-size:11px;color:#000000;font-style:italic;font-weight:normal;">From </xhtml:span><xhtml:span style="font-family:'Fidelity Futura Std Book',Arial,Helvetica,sans-serif;font-size:11px;color:#000000;font-style:italic;font-weight:normal;">January 30, 2019</xhtml:span></link:footnote>
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          xlink:from="footnoteSV1-SV2-PROS000063743AAR_A_IndexIXYQL"
          xlink:to="footnoteSV1-SV2-PROS000063743AAR_A"
          xlink:type="arc"/>
        <link:loc
          xlink:href="#footnoteSV1-SV2-PROS000049310AAR_A_IndexIXYXO"
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          xlink:type="locator"/>
        <link:footnote id="footnoteSV1-SV2-PROS000049310AAR_A" xlink:label="footnoteSV1-SV2-PROS000049310AAR_A" xlink:role="http://www.xbrl.org/2003/role/footnote" xlink:type="resource" xml:lang="en-US"><xhtml:span style="font-family:'Fidelity Futura Std Book',Arial,Helvetica,sans-serif;font-size:6px;color:#000000;font-style:normal;vertical-align:super;font-weight:normal;">A</xhtml:span><xhtml:span style="font-family:'Fidelity Futura Std Book',Arial,Helvetica,sans-serif;font-size:11px;color:#000000;font-style:italic;font-weight:normal;">From </xhtml:span><xhtml:span style="font-family:'Fidelity Futura Std Book',Arial,Helvetica,sans-serif;font-size:11px;color:#000000;font-style:italic;font-weight:normal;">May 29, 2015</xhtml:span></link:footnote>
        <link:footnoteArc
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          xlink:from="footnoteSV1-SV2-PROS000049310AAR_A_IndexIXYXO"
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        <link:loc
          xlink:href="#footnoteSV1-SV2-PROS000049309AAR_A_IndexIXYXN"
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          xlink:type="locator"/>
        <link:footnote id="footnoteSV1-SV2-PROS000049309AAR_A" xlink:label="footnoteSV1-SV2-PROS000049309AAR_A" xlink:role="http://www.xbrl.org/2003/role/footnote" xlink:type="resource" xml:lang="en-US"><xhtml:span style="font-family:'Fidelity Futura Std Book',Arial,Helvetica,sans-serif;font-size:6px;color:#000000;font-style:normal;vertical-align:super;font-weight:normal;">A</xhtml:span><xhtml:span style="font-family:'Fidelity Futura Std Book',Arial,Helvetica,sans-serif;font-size:11px;color:#000000;font-style:italic;font-weight:normal;">From </xhtml:span><xhtml:span style="font-family:'Fidelity Futura Std Book',Arial,Helvetica,sans-serif;font-size:11px;color:#000000;font-style:italic;font-weight:normal;">May 29, 2015</xhtml:span></link:footnote>
        <link:footnoteArc
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          xlink:from="footnoteSV1-SV2-PROS000049309AAR_A_IndexIXYXN"
          xlink:to="footnoteSV1-SV2-PROS000049309AAR_A"
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        <link:loc
          xlink:href="#footnoteIIV-PROS000059762AAR_A_IndexIXYEH"
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        <link:footnote id="footnoteIIV-PROS000059762AAR_A" xlink:label="footnoteIIV-PROS000059762AAR_A" xlink:role="http://www.xbrl.org/2003/role/footnote" xlink:type="resource" xml:lang="en-US"><xhtml:span style="font-family:'Fidelity Futura Std Book',Arial,Helvetica,sans-serif;font-size:6px;color:#000000;font-style:normal;vertical-align:super;font-weight:normal;">A</xhtml:span><xhtml:span style="font-family:'Fidelity Futura Std Book',Arial,Helvetica,sans-serif;font-size:11px;color:#000000;font-style:italic;font-weight:normal;">From </xhtml:span><xhtml:span style="font-family:'Fidelity Futura Std Book',Arial,Helvetica,sans-serif;font-size:11px;color:#000000;font-style:italic;font-weight:normal;">December 19, 2017</xhtml:span></link:footnote>
        <link:footnoteArc
          xlink:arcrole="http://www.xbrl.org/2003/arcrole/fact-footnote"
          xlink:from="footnoteIIV-PROS000059762AAR_A_IndexIXYEH"
          xlink:to="footnoteIIV-PROS000059762AAR_A"
          xlink:type="arc"/>
        <link:loc
          xlink:href="#footnoteSV6-PROAOE_A_FW"
          xlink:label="footnoteSV6-PROAOE_A_FW"
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        <link:footnote id="footnoteSV6-PROAOE_A" xlink:label="footnoteSV6-PROAOE_A" xlink:role="http://www.xbrl.org/2003/role/footnote" xlink:type="resource" xml:lang="en-US"><xhtml:span style="font-family:'Fidelity Futura Std Book',Arial,Helvetica,sans-serif;font-size:6px;color:#000000;font-style:normal;vertical-align:super;font-weight:normal;">A</xhtml:span><xhtml:span style="font-family:'Fidelity Futura Std Book',Arial,Helvetica,sans-serif;font-size:11px;color:#000000;font-style:normal;font-weight:normal;"><xhtml:span style="padding-right:10px"/></xhtml:span><xhtml:span style="font-family:'Fidelity Futura Std Book',Arial,Helvetica,sans-serif;font-size:11px;color:#000000;font-style:normal;font-weight:normal;">Fidelity Management &amp; Research Company LLC (FMR) has contractually agreed to reimburse the fund to the extent that total operating expenses (excluding interest, certain taxes, fees and expenses of the Independent Trustees, proxy and shareholder meeting expenses, extraordinary expenses, and acquired fund fees and expenses (including fees and expenses associated with a wholly owned subsidiary), if any, as well as non-operating expenses such as brokerage commissions and fees and expenses associated with the fund's securities lending program, if applicable), as a percentage of its average net assets, exceed 0.075% (the Expense Cap). If at any time during the current fiscal year expenses for the fund fall below the Expense Cap, FMR reserves the right to recoup through the end of the fiscal year any expenses that were reimbursed during the current fiscal year up to, but not in excess of, the Expense Cap. This arrangement will remain in effect through </xhtml:span><xhtml:span style="font-family:'Fidelity Futura Std Book',Arial,Helvetica,sans-serif;font-size:11px;color:#000000;font-style:normal;font-weight:normal;">February 29, 2024</xhtml:span><xhtml:span style="font-family:'Fidelity Futura Std Book',Arial,Helvetica,sans-serif;font-size:11px;color:#000000;font-style:normal;font-weight:normal;">. 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></link:footnote>
        <link:footnoteArc
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          xlink:to="footnoteSV6-PROAOE_A"
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        <link:loc
          xlink:href="#footnoteSV6-PROS000051995AAR_A_IndexMC041"
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        <link:footnote id="footnoteSV6-PROS000051995AAR_A" xlink:label="footnoteSV6-PROS000051995AAR_A" xlink:role="http://www.xbrl.org/2003/role/footnote" xlink:type="resource" xml:lang="en-US"><xhtml:span style="font-family:'Fidelity Futura Std Book',Arial,Helvetica,sans-serif;font-size:6px;color:#000000;font-style:normal;vertical-align:super;font-weight:normal;">A</xhtml:span><xhtml:span style="font-family:'Fidelity Futura Std Book',Arial,Helvetica,sans-serif;font-size:11px;color:#000000;font-style:italic;font-weight:normal;">From </xhtml:span><xhtml:span style="font-family:'Fidelity Futura Std Book',Arial,Helvetica,sans-serif;font-size:11px;color:#000000;font-style:italic;font-weight:normal;">January 5, 2016</xhtml:span></link:footnote>
        <link:footnoteArc
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          xlink:from="footnoteSV6-PROS000051995AAR_A_IndexMC041"
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        <link:loc
          xlink:href="#footnoteUSY-I-ISY-I-PROS000057365AAR_A_IndexIXWWZ"
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          xlink:type="locator"/>
        <link:footnote id="footnoteUSY-I-ISY-I-PROS000057365AAR_A" xlink:label="footnoteUSY-I-ISY-I-PROS000057365AAR_A" xlink:role="http://www.xbrl.org/2003/role/footnote" xlink:type="resource" xml:lang="en-US"><xhtml:span style="font-family:'Fidelity Futura Std Book',Arial,Helvetica,sans-serif;font-size:6px;color:#000000;font-style:normal;vertical-align:super;font-weight:normal;">A</xhtml:span><xhtml:span style="font-family:'Fidelity Futura Std Book',Arial,Helvetica,sans-serif;font-size:11px;color:#000000;font-style:italic;font-weight:normal;">From </xhtml:span><xhtml:span style="font-family:'Fidelity Futura Std Book',Arial,Helvetica,sans-serif;font-size:11px;color:#000000;font-style:italic;font-weight:normal;">May 9, 2017</xhtml:span></link:footnote>
        <link:footnoteArc
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          xlink:from="footnoteUSY-I-ISY-I-PROS000057365AAR_A_IndexIXWWZ"
          xlink:to="footnoteUSY-I-ISY-I-PROS000057365AAR_A"
          xlink:type="arc"/>
        <link:loc
          xlink:href="#footnoteUSY-I-ISY-I-PROS000057366AAR_A_IndexIXZFH"
          xlink:label="footnoteUSY-I-ISY-I-PROS000057366AAR_A_IndexIXZFH"
          xlink:type="locator"/>
        <link:footnote id="footnoteUSY-I-ISY-I-PROS000057366AAR_A" xlink:label="footnoteUSY-I-ISY-I-PROS000057366AAR_A" xlink:role="http://www.xbrl.org/2003/role/footnote" xlink:type="resource" xml:lang="en-US"><xhtml:span style="font-family:'Fidelity Futura Std Book',Arial,Helvetica,sans-serif;font-size:6px;color:#000000;font-style:normal;vertical-align:super;font-weight:normal;">A</xhtml:span><xhtml:span style="font-family:'Fidelity Futura Std Book',Arial,Helvetica,sans-serif;font-size:11px;color:#000000;font-style:italic;font-weight:normal;">From </xhtml:span><xhtml:span style="font-family:'Fidelity Futura Std Book',Arial,Helvetica,sans-serif;font-size:11px;color:#000000;font-style:italic;font-weight:normal;">May 9, 2017</xhtml:span></link:footnote>
        <link:footnoteArc
          xlink:arcrole="http://www.xbrl.org/2003/arcrole/fact-footnote"
          xlink:from="footnoteUSY-I-ISY-I-PROS000057366AAR_A_IndexIXZFH"
          xlink:to="footnoteUSY-I-ISY-I-PROS000057366AAR_A"
          xlink:type="arc"/>
        <link:loc
          xlink:href="#footnoteTI1-I-PROS000054097AAR_A_IndexIX425"
          xlink:label="footnoteTI1-I-PROS000054097AAR_A_IndexIX425"
          xlink:type="locator"/>
        <link:footnote id="footnoteTI1-I-PROS000054097AAR_A" xlink:label="footnoteTI1-I-PROS000054097AAR_A" xlink:role="http://www.xbrl.org/2003/role/footnote" xlink:type="resource" xml:lang="en-US"><xhtml:span style="font-family:'Fidelity Futura Std Book',Arial,Helvetica,sans-serif;font-size:6px;color:#000000;font-style:normal;vertical-align:super;font-weight:normal;">A</xhtml:span><xhtml:span style="font-family:'Fidelity Futura Std Book',Arial,Helvetica,sans-serif;font-size:11px;color:#000000;font-style:italic;font-weight:normal;">From </xhtml:span><xhtml:span style="font-family:'Fidelity Futura Std Book',Arial,Helvetica,sans-serif;font-size:11px;color:#000000;font-style:italic;font-weight:normal;">June 7, 2016</xhtml:span></link:footnote>
        <link:footnoteArc
          xlink:arcrole="http://www.xbrl.org/2003/arcrole/fact-footnote"
          xlink:from="footnoteTI1-I-PROS000054097AAR_A_IndexIX425"
          xlink:to="footnoteTI1-I-PROS000054097AAR_A"
          xlink:type="arc"/>
        <link:loc
          xlink:href="#footnoteSGX-PROAOE_A_FW"
          xlink:label="footnoteSGX-PROAOE_A_FW"
          xlink:type="locator"/>
        <link:footnote id="footnoteSGX-PROAOE_A" xlink:label="footnoteSGX-PROAOE_A" xlink:role="http://www.xbrl.org/2003/role/footnote" xlink:type="resource" xml:lang="en-US"><xhtml:span style="font-family:'Fidelity Futura Std Book',Arial,Helvetica,sans-serif;font-size:6px;color:#000000;font-style:normal;vertical-align:super;font-weight:normal;">A</xhtml:span><xhtml:span style="font-family:'Fidelity Futura Std Book',Arial,Helvetica,sans-serif;font-size:11px;color:#000000;font-style:normal;font-weight:normal;"><xhtml:span style="padding-right:10px"/></xhtml:span><xhtml:span style="font-family:'Fidelity Futura Std Book',Arial,Helvetica,sans-serif;font-size:11px;color:#000000;font-style:normal;font-weight:normal;">Fidelity Management &amp; Research Company LLC (FMR) has contractually agreed to reimburse the fund to the extent that total operating expenses (excluding interest, fees and expenses of the Independent Trustees, 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 0.013% (the Expense Cap). If at any time during the current fiscal year expenses for the fund fall below the Expense Cap, FMR reserves the right to recoup through the end of the fiscal year any expenses that were reimbursed during the current fiscal year up to, but not in excess of, the Expense Cap. This arrangement will remain in effect through </xhtml:span><xhtml:span style="font-family:'Fidelity Futura Std Book',Arial,Helvetica,sans-serif;font-size:11px;color:#000000;font-style:normal;font-weight:normal;">February 28, 2026</xhtml:span><xhtml:span style="font-family:'Fidelity Futura Std Book',Arial,Helvetica,sans-serif;font-size:11px;color:#000000;font-style:normal;font-weight:normal;">. 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></link:footnote>
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