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    <rr:RiskReturnHeading contextRef="S000031547_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member">         Fund Summary
                  Fund:Fidelity&#xae; Series Emerging Markets Debt Fund

</rr:RiskReturnHeading>
    <rr:ObjectiveHeading contextRef="S000031547_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member">         Investment Objective

</rr:ObjectiveHeading>
    <rr:ObjectivePrimaryTextBlock contextRef="S000031547_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member">         The fund seeks high total return.

</rr:ObjectivePrimaryTextBlock>
    <rr:ExpenseHeading contextRef="S000031547_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member">         Fee Table

</rr:ExpenseHeading>
    <rr:ExpenseNarrativeTextBlock contextRef="S000031547_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member">         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="S000031547_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member">         Shareholder fees

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    <rr:OperatingExpensesCaption contextRef="S000031547_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member">         Annual Operating Expenses
                  (expenses that you pay each year as a % of the value of your investment)

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      unitRef="pure">0</rr:ManagementFeesOverAssets>
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      unitRef="pure">0.0000</rr:ExpensesOverAssets>
    <rr:ExpenseExampleNarrativeTextBlock contextRef="S000031547_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member">         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 your shareholder 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:


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    <rr:PortfolioTurnoverHeading contextRef="S000031547_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member">Portfolio Turnover

</rr:PortfolioTurnoverHeading>
    <rr:PortfolioTurnoverTextBlock contextRef="S000031547_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member">         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 29%  of the average value of its portfolio.


</rr:PortfolioTurnoverTextBlock>
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    <rr:StrategyHeading contextRef="S000031547_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member">         Principal Investment Strategies

</rr:StrategyHeading>
    <rr:StrategyNarrativeTextBlock contextRef="S000031547_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member">
            Normally investing at least 80% of assets in debt securities of issuers in emerging markets (countries that have an emerging
               stock market as defined by MSCI, countries or markets with low- to middle-income economies as classified by the World Bank,
               and other countries or markets with similar emerging characteristics) and other debt investments that are tied economically
               to emerging markets.



            Potentially investing in other types of securities, including debt securities of non-emerging market foreign issuers and lower-quality
               debt securities (those of less than investment-grade quality, also referred to as high yield debt securities or junk bonds)
               of U.S. issuers.



            Allocating investments across different emerging market countries.


            Analyzing a security's structural features and current pricing, trading opportunities, and the credit, currency, and economic
               risks of the security and its issuer to select investments.



</rr:StrategyNarrativeTextBlock>
    <rr:RiskHeading contextRef="S000031547_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member">         Principal Investment Risks

</rr:RiskHeading>
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            Interest Rate Changes.&#160;Interest rate increases can cause the price of a debt security to decrease.



            Foreign and Emerging Market Risk.&#160;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.&#160;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. Lower-quality debt securities (those of less than investment-grade quality, also referred to as high yield debt securities
               or junk bonds) and certain types of other securities involve greater risk of default or price changes due to changes in the
               credit quality of the issuer. The value of lower-quality debt securities and certain types of other securities can be more volatile due to increased sensitivity
               to adverse issuer, political, regulatory, market, or economic developments and can be difficult to resell.


                  In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that
               it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified
               fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than
               would occur in a more diversified fund.

         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.  You could lose money by investing in the fund.


</rr:RiskNarrativeTextBlock>
    <rr:RiskNondiversifiedStatus contextRef="S000031547_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member">In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that
               it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified
               fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than
               would occur in a more diversified fund.</rr:RiskNondiversifiedStatus>
    <rr:RiskNotInsuredDepositoryInstitution contextRef="S000031547_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member">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="S000031547_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member">You could lose money by investing in the fund.</rr:RiskLoseMoney>
    <rr:BarChartAndPerformanceTableHeading contextRef="S000031547_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member">         Performance

</rr:BarChartAndPerformanceTableHeading>
    <rr:PerformanceNarrativeTextBlock contextRef="S000031547_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member">                  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>
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               of the fund's shares to the performance of a securities market index over various periods of time.</rr:PerformanceInformationIllustratesVariabilityOfReturns>
    <rr:PerformancePastDoesNotIndicateFuture contextRef="S000031547_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member">Past performance (before and after taxes) is not an indication of future performance.</rr:PerformancePastDoesNotIndicateFuture>
    <rr:PerformanceAvailabilityWebSiteAddress contextRef="S000031547_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member">www.fidelity.com</rr:PerformanceAvailabilityWebSiteAddress>
    <rr:BarChartHeading contextRef="S000031547_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member">         Year-by-Year Returns

</rr:BarChartHeading>
    <rr:HighestQuarterlyReturnLabel contextRef="S000031547_C000098197_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member">Highest Quarter Return</rr:HighestQuarterlyReturnLabel>
    <rr:BarChartHighestQuarterlyReturn
      contextRef="S000031547_C000098197_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member"
      decimals="4"
      unitRef="pure">0.1287</rr:BarChartHighestQuarterlyReturn>
    <rr:BarChartHighestQuarterlyReturnDate contextRef="S000031547_C000098197_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member">2020-06-30</rr:BarChartHighestQuarterlyReturnDate>
    <rr:LowestQuarterlyReturnLabel contextRef="S000031547_C000098197_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member">Lowest Quarter Return</rr:LowestQuarterlyReturnLabel>
    <rr:BarChartLowestQuarterlyReturn
      contextRef="S000031547_C000098197_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member"
      decimals="4"
      unitRef="pure">-0.1485</rr:BarChartLowestQuarterlyReturn>
    <rr:BarChartLowestQuarterlyReturnDate contextRef="S000031547_C000098197_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member">2020-03-31</rr:BarChartLowestQuarterlyReturnDate>
    <rr:PerformanceTableHeading contextRef="S000031547_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member">Average Annual Returns

</rr:PerformanceTableHeading>
    <rr:PerformanceTableNarrativeTextBlock contextRef="S000031547_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member">         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="S000031547_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member">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="S000031547_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member">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="S000031547_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member">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="S000031547_C000098197_ReturnBeforeTaxes_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member">Return Before Taxes</rr:AverageAnnualReturnLabel>
    <rr:AverageAnnualReturnYear01
      contextRef="S000031547_C000098197_ReturnBeforeTaxes_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member"
      decimals="4"
      unitRef="pure">-0.0060</rr:AverageAnnualReturnYear01>
    <rr:AverageAnnualReturnYear05
      contextRef="S000031547_C000098197_ReturnBeforeTaxes_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member"
      decimals="4"
      unitRef="pure">0.0394</rr:AverageAnnualReturnYear05>
    <rr:AverageAnnualReturnYear10
      contextRef="S000031547_C000098197_ReturnBeforeTaxes_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member"
      decimals="4"
      unitRef="pure">0.0517</rr:AverageAnnualReturnYear10>
    <rr:AverageAnnualReturnLabel contextRef="S000031547_C000098197_AfterTaxesOnDistributions_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member">Return After Taxes on Distributions</rr:AverageAnnualReturnLabel>
    <rr:AverageAnnualReturnYear01
      contextRef="S000031547_C000098197_AfterTaxesOnDistributions_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member"
      decimals="4"
      unitRef="pure">-0.0239</rr:AverageAnnualReturnYear01>
    <rr:AverageAnnualReturnYear05
      contextRef="S000031547_C000098197_AfterTaxesOnDistributions_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member"
      decimals="4"
      unitRef="pure">0.0151</rr:AverageAnnualReturnYear05>
    <rr:AverageAnnualReturnYear10
      contextRef="S000031547_C000098197_AfterTaxesOnDistributions_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member"
      decimals="4"
      unitRef="pure">0.0263</rr:AverageAnnualReturnYear10>
    <rr:AverageAnnualReturnLabel contextRef="S000031547_C000098197_AfterTaxesOnDistributionsAndSales_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member">Return After Taxes on Distributions and Sale of Fund Shares</rr:AverageAnnualReturnLabel>
    <rr:AverageAnnualReturnYear01
      contextRef="S000031547_C000098197_AfterTaxesOnDistributionsAndSales_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member"
      decimals="4"
      unitRef="pure">-0.0036</rr:AverageAnnualReturnYear01>
    <rr:AverageAnnualReturnYear05
      contextRef="S000031547_C000098197_AfterTaxesOnDistributionsAndSales_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member"
      decimals="4"
      unitRef="pure">0.0195</rr:AverageAnnualReturnYear05>
    <rr:AverageAnnualReturnYear10
      contextRef="S000031547_C000098197_AfterTaxesOnDistributionsAndSales_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member"
      decimals="4"
      unitRef="pure">0.0285</rr:AverageAnnualReturnYear10>
    <rr:AverageAnnualReturnLabel contextRef="S000031547_IndexJP045_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member">J.P. Morgan Emerging Markets Bond Index Global</rr:AverageAnnualReturnLabel>
    <rr:AverageAnnualReturnYear01
      contextRef="S000031547_IndexJP045_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member"
      decimals="4"
      unitRef="pure">-0.0151</rr:AverageAnnualReturnYear01>
    <rr:AverageAnnualReturnYear05
      contextRef="S000031547_IndexJP045_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member"
      decimals="4"
      unitRef="pure">0.0447</rr:AverageAnnualReturnYear05>
    <rr:AverageAnnualReturnYear10
      contextRef="S000031547_IndexJP045_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member"
      decimals="4"
      unitRef="pure">0.0495</rr:AverageAnnualReturnYear10>
    <rr:RiskReturnHeading contextRef="S000069413_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member">                  Fund Summary
                  Fund:Fidelity&#xae; Series Emerging Markets Debt Local Currency Fund

</rr:RiskReturnHeading>
    <rr:ObjectiveHeading contextRef="S000069413_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member">         Investment Objective

</rr:ObjectiveHeading>
    <rr:ObjectivePrimaryTextBlock contextRef="S000069413_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member">         The fund seeks high total return.

</rr:ObjectivePrimaryTextBlock>
    <rr:ExpenseHeading contextRef="S000069413_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member">         Fee Table

</rr:ExpenseHeading>
    <rr:ExpenseNarrativeTextBlock contextRef="S000069413_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member">         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="S000069413_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member">         Shareholder fees

</rr:ShareholderFeesCaption>
    <rr:ShareholderFeeOther
      contextRef="S000069413_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member"
      decimals="0"
      unitRef="usd">0</rr:ShareholderFeeOther>
    <rr:OperatingExpensesCaption contextRef="S000069413_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member">                  Annual Operating Expenses
                  (expenses that you pay each year as a % of the value of your investment)

</rr:OperatingExpensesCaption>
    <rr:ManagementFeesOverAssets
      contextRef="S000069413_C000221495_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member"
      decimals="4"
      unitRef="pure">0</rr:ManagementFeesOverAssets>
    <rr:DistributionAndService12b1FeesOverAssets
      contextRef="S000069413_C000221495_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member"
      decimals="4"
      unitRef="pure">0</rr:DistributionAndService12b1FeesOverAssets>
    <rr:OtherExpensesOverAssets
      contextRef="S000069413_C000221495_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member"
      decimals="4"
      unitRef="pure">0.0003</rr:OtherExpensesOverAssets>
    <rr:ExpensesOverAssets
      contextRef="S000069413_C000221495_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member"
      decimals="4"
      unitRef="pure">0.0003</rr:ExpensesOverAssets>
    <rr:FeeWaiverOrReimbursementOverAssets
      contextRef="S000069413_C000221495_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member"
      decimals="4"
      id="id_footnote_elem_780063778_68"
      unitRef="pure">-0.0003</rr:FeeWaiverOrReimbursementOverAssets>
    <rr:NetExpensesOverAssets
      contextRef="S000069413_C000221495_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member"
      decimals="4"
      unitRef="pure">0.0000</rr:NetExpensesOverAssets>
    <rr:FeeWaiverOrReimbursementOverAssetsDateOfTermination contextRef="S000069413_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member">April 30, 2025</rr:FeeWaiverOrReimbursementOverAssetsDateOfTermination>
    <rr:ExpenseExampleNarrativeTextBlock contextRef="S000069413_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member">                  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 your shareholder 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="S000069413_C000221495_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member"
      decimals="0"
      unitRef="usd">0</rr:ExpenseExampleYear01>
    <rr:ExpenseExampleYear03
      contextRef="S000069413_C000221495_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member"
      decimals="0"
      unitRef="usd">0</rr:ExpenseExampleYear03>
    <rr:ExpenseExampleYear05
      contextRef="S000069413_C000221495_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member"
      decimals="0"
      unitRef="usd">6</rr:ExpenseExampleYear05>
    <rr:ExpenseExampleYear10
      contextRef="S000069413_C000221495_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member"
      decimals="0"
      unitRef="usd">28</rr:ExpenseExampleYear10>
    <rr:PortfolioTurnoverHeading contextRef="S000069413_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member">         Portfolio Turnover

</rr:PortfolioTurnoverHeading>
    <rr:PortfolioTurnoverTextBlock contextRef="S000069413_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member">         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 65%  of the average value of its portfolio.


</rr:PortfolioTurnoverTextBlock>
    <rr:PortfolioTurnoverRate
      contextRef="S000069413_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member"
      decimals="4"
      unitRef="pure">0.65</rr:PortfolioTurnoverRate>
    <rr:StrategyHeading contextRef="S000069413_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member">         Principal Investment Strategies

</rr:StrategyHeading>
    <rr:StrategyNarrativeTextBlock contextRef="S000069413_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member">
            Normally investing at least 80% of assets in debt securities of issuers in emerging markets and other debt investments that
               are tied economically to emerging markets and denominated in the local currency of the issuer. Emerging markets include countries
               that have an emerging stock market as defined by MSCI, countries or markets with low- to middle-income economies as classified
               by currency of the World Bank, and other countries or markets with similar emerging characteristics. Emerging markets tend
               to have relatively low gross national product per capita compared to the world&#x92;s major economies and may have the potential
               for rapid economic growth.



            Potentially investing in other types of securities, including debt securities of non-emerging market foreign issuers and lower-quality
               debt securities (those of less than investment-grade quality, also referred to as high yield debt securities or junk bonds)
               of U.S. issuers.



            Allocating investments across different emerging market countries.


            Actively managing the fund&#x92;s currency exposures.


            Utilizing forward foreign currency exchange contracts for both hedging and non-hedging purposes.


            Analyzing a security's structural features and current pricing, trading opportunities, and the credit, currency, and economic
               risks of the security and its issuer to select investments.



</rr:StrategyNarrativeTextBlock>
    <rr:RiskHeading contextRef="S000069413_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member">         Principal Investment Risks

</rr:RiskHeading>
    <rr:RiskNarrativeTextBlock contextRef="S000069413_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member">
            Interest Rate Changes.&#160;Interest rate increases can cause the price of a debt security to decrease.



            Foreign and Emerging Market Risk.&#160;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.



            Foreign Currency Transactions.&#160;The fund may enter into forward foreign currency exchange contracts for both hedging and non-hedging purposes. A forward foreign
               currency exchange contract, which involves an obligation to purchase or sell a specific currency at a future date at a price
               set at the time of the contract, reduces a fund&#x92;s exposure to changes in the value of the currency it will deliver and
               increases its exposure to changes in the value of the currency it will receive for the duration of the contract. Foreign exchange
               rates can be extremely volatile and the degree of volatility of the market or in the direction of the market from that anticipated
               by the Adviser may result in losses to the fund.



            Currency Exposure.&#160;Because the fund is normally heavily exposed to foreign currencies, it could experience losses based solely on the weakness
               of foreign currencies versus the U.S. dollar and changes in the exchange rates between foreign currencies and the U.S. dollar.
               Currency risk may be particularly high to the extent that a fund invests in foreign currencies or engages in foreign currency
               transactions that are economically tied to emerging market countries. These emerging markets currency transactions may present
               market, credit, currency, liquidity, legal, political and other risks different from, or greater than, the risks of investing
               in developed foreign currencies or engaging in foreign currency transactions that are economically tied to developed foreign
               countries.



            Issuer-Specific Changes.&#160;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. Lower-quality debt securities (those of less than investment-grade quality, also referred to as high yield debt securities
               or junk bonds) and certain types of other securities involve greater risk of default or price changes due to changes in the
               credit quality of the issuer. The value of lower-quality debt securities and certain types of other securities can be more volatile due to increased sensitivity
               to adverse issuer, political, regulatory, market, or economic developments and can be difficult to resell.


                  In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that
               it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified
               fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than
               would occur in a more diversified fund.

         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.  You could lose money by investing in the fund.


</rr:RiskNarrativeTextBlock>
    <rr:RiskNondiversifiedStatus contextRef="S000069413_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member">In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that
               it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified
               fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than
               would occur in a more diversified fund.</rr:RiskNondiversifiedStatus>
    <rr:RiskNotInsuredDepositoryInstitution contextRef="S000069413_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member">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="S000069413_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member">You could lose money by investing in the fund.</rr:RiskLoseMoney>
    <rr:BarChartAndPerformanceTableHeading contextRef="S000069413_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member">         Performance

</rr:BarChartAndPerformanceTableHeading>
    <rr:PerformanceNarrativeTextBlock contextRef="S000069413_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member">                  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="S000069413_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member">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="S000069413_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member">Past performance (before and after taxes) is not an indication of future performance.</rr:PerformancePastDoesNotIndicateFuture>
    <rr:PerformanceAvailabilityWebSiteAddress contextRef="S000069413_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member">www.fidelity.com</rr:PerformanceAvailabilityWebSiteAddress>
    <rr:BarChartHeading contextRef="S000069413_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member">         Year-by-Year Returns

</rr:BarChartHeading>
    <rr:HighestQuarterlyReturnLabel contextRef="S000069413_C000221495_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member">Highest Quarter Return</rr:HighestQuarterlyReturnLabel>
    <rr:BarChartHighestQuarterlyReturn
      contextRef="S000069413_C000221495_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member"
      decimals="4"
      unitRef="pure">0.0349</rr:BarChartHighestQuarterlyReturn>
    <rr:BarChartHighestQuarterlyReturnDate contextRef="S000069413_C000221495_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member">2021-06-30</rr:BarChartHighestQuarterlyReturnDate>
    <rr:LowestQuarterlyReturnLabel contextRef="S000069413_C000221495_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member">Lowest Quarter Return</rr:LowestQuarterlyReturnLabel>
    <rr:BarChartLowestQuarterlyReturn
      contextRef="S000069413_C000221495_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member"
      decimals="4"
      unitRef="pure">-0.0656</rr:BarChartLowestQuarterlyReturn>
    <rr:BarChartLowestQuarterlyReturnDate contextRef="S000069413_C000221495_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member">2021-03-31</rr:BarChartLowestQuarterlyReturnDate>
    <rr:PerformanceTableHeading contextRef="S000069413_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member">         Average Annual Returns

</rr:PerformanceTableHeading>
    <rr:PerformanceTableNarrativeTextBlock contextRef="S000069413_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member">         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="S000069413_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member">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="S000069413_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member">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="S000069413_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member">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="S000069413_C000221495_ReturnBeforeTaxes_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member">Return Before Taxes</rr:AverageAnnualReturnLabel>
    <rr:AverageAnnualReturnYear01
      contextRef="S000069413_C000221495_ReturnBeforeTaxes_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member"
      decimals="4"
      unitRef="pure">-0.0856</rr:AverageAnnualReturnYear01>
    <rr:AverageAnnualReturnSinceInception
      contextRef="S000069413_C000221495_ReturnBeforeTaxes_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member"
      decimals="4"
      id="id_footnote_elem_780064078_100"
      unitRef="pure">-0.0049</rr:AverageAnnualReturnSinceInception>
    <rr:AverageAnnualReturnLabel contextRef="S000069413_C000221495_AfterTaxesOnDistributions_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member">Return After Taxes on Distributions</rr:AverageAnnualReturnLabel>
    <rr:AverageAnnualReturnYear01
      contextRef="S000069413_C000221495_AfterTaxesOnDistributions_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member"
      decimals="4"
      unitRef="pure">-0.1028</rr:AverageAnnualReturnYear01>
    <rr:AverageAnnualReturnSinceInception
      contextRef="S000069413_C000221495_AfterTaxesOnDistributions_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member"
      decimals="4"
      id="id_footnote_elem_780064078_103"
      unitRef="pure">-0.0230</rr:AverageAnnualReturnSinceInception>
    <rr:AverageAnnualReturnLabel contextRef="S000069413_C000221495_AfterTaxesOnDistributionsAndSales_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member">Return After Taxes on Distributions and Sale of Fund Shares</rr:AverageAnnualReturnLabel>
    <rr:AverageAnnualReturnYear01
      contextRef="S000069413_C000221495_AfterTaxesOnDistributionsAndSales_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member"
      decimals="4"
      unitRef="pure">-0.0505</rr:AverageAnnualReturnYear01>
    <rr:AverageAnnualReturnSinceInception
      contextRef="S000069413_C000221495_AfterTaxesOnDistributionsAndSales_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member"
      decimals="4"
      id="id_footnote_elem_780064078_106"
      unitRef="pure">-0.0111</rr:AverageAnnualReturnSinceInception>
    <rr:AverageAnnualReturnLabel contextRef="S000069413_IndexJP084_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member">J.P. Morgan GBI-EM Global Diversified Index</rr:AverageAnnualReturnLabel>
    <rr:AverageAnnualReturnYear01
      contextRef="S000069413_IndexJP084_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member"
      decimals="4"
      unitRef="pure">-0.0875</rr:AverageAnnualReturnYear01>
    <rr:AverageAnnualReturnSinceInception
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      unitRef="pure">-0.0034</rr:AverageAnnualReturnSinceInception>
    <rr:AnnualReturnInceptionDate contextRef="S000069413_D1231FidelitySeriesEmergingMarketsDebtFundsComboPRO02Member">2020-10-30</rr:AnnualReturnInceptionDate>
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                  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 0.003% (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
                  April 30, 2025 . FMR may not terminate this arrangement before the expiration date without the approval of the Board of Trustees and may
                  extend it in its discretion after that date.</xhtml:span></xhtml:i></xhtml:p>

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