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    <dei:EntityRegistrantName contextRef="Trust">NORTH CAROLINA CAPITAL MANAGEMENT TRUST</dei:EntityRegistrantName>
    <rr:RiskReturnHeading contextRef="S000007506_D0630NorthCarolinaCapitalManagementTrustPRO14Member">         Fund Summary
                  Fund:Government Portfolio

</rr:RiskReturnHeading>
    <rr:ObjectiveHeading contextRef="S000007506_D0630NorthCarolinaCapitalManagementTrustPRO14Member">         Investment Objective

</rr:ObjectiveHeading>
    <rr:ObjectivePrimaryTextBlock contextRef="S000007506_D0630NorthCarolinaCapitalManagementTrustPRO14Member">         The fund seeks to obtain as high a level of current income as is consistent with the preservation of capital and liquidity
            and to maintain a constant net asset value of $1.00 per share.


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    <rr:ExpenseHeading contextRef="S000007506_D0630NorthCarolinaCapitalManagementTrustPRO14Member">         Fee Table

</rr:ExpenseHeading>
    <rr:ExpenseNarrativeTextBlock contextRef="S000007506_D0630NorthCarolinaCapitalManagementTrustPRO14Member">         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, you may pay other fees, such as fees to financial intermediaries.


</rr:ExpenseNarrativeTextBlock>
    <rr:ShareholderFeesCaption contextRef="S000007506_D0630NorthCarolinaCapitalManagementTrustPRO14Member">         Shareholder fees

</rr:ShareholderFeesCaption>
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      contextRef="S000007506_D0630NorthCarolinaCapitalManagementTrustPRO14Member"
      decimals="0"
      unitRef="usd">0</rr:ShareholderFeeOther>
    <rr:OperatingExpensesCaption contextRef="S000007506_D0630NorthCarolinaCapitalManagementTrustPRO14Member">                  Annual Operating Expenses
                  (expenses that you pay each year as a % of the value of your investment)

</rr:OperatingExpensesCaption>
    <rr:ManagementFeesOverAssets
      contextRef="S000007506_C000020486_D0630NorthCarolinaCapitalManagementTrustPRO14Member"
      decimals="4"
      unitRef="pure">0.0016</rr:ManagementFeesOverAssets>
    <rr:DistributionAndService12b1FeesOverAssets
      contextRef="S000007506_C000020486_D0630NorthCarolinaCapitalManagementTrustPRO14Member"
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      unitRef="pure">0.0006</rr:DistributionAndService12b1FeesOverAssets>
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      contextRef="S000007506_C000020486_D0630NorthCarolinaCapitalManagementTrustPRO14Member"
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    <rr:ExpensesOverAssets
      contextRef="S000007506_C000020486_D0630NorthCarolinaCapitalManagementTrustPRO14Member"
      decimals="4"
      unitRef="pure">0.0022</rr:ExpensesOverAssets>
    <rr:ExpenseExampleNarrativeTextBlock contextRef="S000007506_D0630NorthCarolinaCapitalManagementTrustPRO14Member">                  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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      contextRef="S000007506_C000020486_D0630NorthCarolinaCapitalManagementTrustPRO14Member"
      decimals="0"
      unitRef="usd">23</rr:ExpenseExampleYear01>
    <rr:ExpenseExampleYear03
      contextRef="S000007506_C000020486_D0630NorthCarolinaCapitalManagementTrustPRO14Member"
      decimals="0"
      unitRef="usd">71</rr:ExpenseExampleYear03>
    <rr:ExpenseExampleYear05
      contextRef="S000007506_C000020486_D0630NorthCarolinaCapitalManagementTrustPRO14Member"
      decimals="0"
      unitRef="usd">124</rr:ExpenseExampleYear05>
    <rr:ExpenseExampleYear10
      contextRef="S000007506_C000020486_D0630NorthCarolinaCapitalManagementTrustPRO14Member"
      decimals="0"
      unitRef="usd">280</rr:ExpenseExampleYear10>
    <rr:StrategyHeading contextRef="S000007506_D0630NorthCarolinaCapitalManagementTrustPRO14Member">Principal Investment Strategies

</rr:StrategyHeading>
    <rr:StrategyNarrativeTextBlock contextRef="S000007506_D0630NorthCarolinaCapitalManagementTrustPRO14Member">
            Normally investing at least 99.5% of total assets in cash, U.S. Government securities and/or repurchase agreements that are
               collateralized fully (i.e., collateralized by cash or government securities), as permitted by North Carolina General Statute
               159-30, as amended (the Statute) and 20 North Carolina Administrative Code 3.0703, as amended (the Code).



            Investing in U.S. Government securities issued by entities that are chartered or sponsored by Congress but whose securities
               are neither issued nor guaranteed by the U.S. Treasury.



            Investing in compliance with industry-standard regulatory requirements for money market funds for the quality, maturity, liquidity,
               and diversification of investments.


                  In addition, the fund normally invests at least 80% of its assets in U.S. Government securities and repurchase agreements
            for those securities.


</rr:StrategyNarrativeTextBlock>
    <rr:RiskHeading contextRef="S000007506_D0630NorthCarolinaCapitalManagementTrustPRO14Member">         Principal Investment Risks

</rr:RiskHeading>
    <rr:RiskNarrativeTextBlock contextRef="S000007506_D0630NorthCarolinaCapitalManagementTrustPRO14Member">
            Interest Rate Changes.&#160;Interest rate increases can cause the price of a money market security to decrease.



            Income Risk.&#160;A low or negative interest rate environment can adversely affect the fund&#x92;s yield.



            Issuer-Specific Changes.&#160;A decline in the credit quality of an issuer or a provider of credit support or a maturity-shortening structure for a security
               can cause the price of a money market security to decrease.


                  You could lose money by investing in the fund.  Although the fund seeks to preserve the value of your investment at $1.00 per share, it cannot guarantee it will do so.  An investment in the fund is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government
               agency.  Fidelity Investments and its affiliates, the fund&#x92;s sponsor, have no legal obligation to provide financial support to
               the fund, and you should not expect that the sponsor will provide financial support to the fund at any time.

         The fund will not impose a fee upon the sale of your shares, nor temporarily suspend your ability to sell shares if the fund's
            weekly liquid assets fall below 30% of its total assets because of market conditions or other factors.


</rr:RiskNarrativeTextBlock>
    <rr:RiskLoseMoney contextRef="S000007506_D0630NorthCarolinaCapitalManagementTrustPRO14Member">You could lose money by investing in the fund.</rr:RiskLoseMoney>
    <rr:RiskMoneyMarketFundMayNotPreserveDollar contextRef="S000007506_D0630NorthCarolinaCapitalManagementTrustPRO14Member">Although the fund seeks to preserve the value of your investment at $1.00 per share, it cannot guarantee it will do so.</rr:RiskMoneyMarketFundMayNotPreserveDollar>
    <rr:RiskNotInsuredDepositoryInstitution contextRef="S000007506_D0630NorthCarolinaCapitalManagementTrustPRO14Member">An investment in the fund is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government
               agency.</rr:RiskNotInsuredDepositoryInstitution>
    <rr:RiskMoneyMarketFundSponsorMayNotProvideSupport contextRef="S000007506_D0630NorthCarolinaCapitalManagementTrustPRO14Member">Fidelity Investments and its affiliates, the fund&#x92;s sponsor, have no legal obligation to provide financial support to
               the fund, and you should not expect that the sponsor will provide financial support to the fund at any time.</rr:RiskMoneyMarketFundSponsorMayNotProvideSupport>
    <rr:BarChartAndPerformanceTableHeading contextRef="S000007506_D0630NorthCarolinaCapitalManagementTrustPRO14Member">         Performance

</rr:BarChartAndPerformanceTableHeading>
    <rr:PerformanceNarrativeTextBlock contextRef="S000007506_D0630NorthCarolinaCapitalManagementTrustPRO14Member">         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.  Past performance is not an indication of future performance.


</rr:PerformanceNarrativeTextBlock>
    <rr:PerformanceInformationIllustratesVariabilityOfReturns contextRef="S000007506_D0630NorthCarolinaCapitalManagementTrustPRO14Member">The information illustrates the changes in the performance of the fund's shares from year to year.</rr:PerformanceInformationIllustratesVariabilityOfReturns>
    <rr:PerformancePastDoesNotIndicateFuture contextRef="S000007506_D0630NorthCarolinaCapitalManagementTrustPRO14Member">Past performance is not an indication of future performance.</rr:PerformancePastDoesNotIndicateFuture>
    <rr:BarChartHeading contextRef="S000007506_D0630NorthCarolinaCapitalManagementTrustPRO14Member">         Year-by-Year Returns

</rr:BarChartHeading>
    <rr:HighestQuarterlyReturnLabel contextRef="S000007506_C000020486_D0630NorthCarolinaCapitalManagementTrustPRO14Member">Highest Quarter Return</rr:HighestQuarterlyReturnLabel>
    <rr:BarChartHighestQuarterlyReturn
      contextRef="S000007506_C000020486_D0630NorthCarolinaCapitalManagementTrustPRO14Member"
      decimals="4"
      unitRef="pure">0.0057</rr:BarChartHighestQuarterlyReturn>
    <rr:BarChartHighestQuarterlyReturnDate contextRef="S000007506_C000020486_D0630NorthCarolinaCapitalManagementTrustPRO14Member">2019-06-30</rr:BarChartHighestQuarterlyReturnDate>
    <rr:LowestQuarterlyReturnLabel contextRef="S000007506_C000020486_D0630NorthCarolinaCapitalManagementTrustPRO14Member">Lowest Quarter Return</rr:LowestQuarterlyReturnLabel>
    <rr:BarChartLowestQuarterlyReturn
      contextRef="S000007506_C000020486_D0630NorthCarolinaCapitalManagementTrustPRO14Member"
      decimals="4"
      unitRef="pure">0.0000</rr:BarChartLowestQuarterlyReturn>
    <rr:BarChartLowestQuarterlyReturnDate contextRef="S000007506_C000020486_D0630NorthCarolinaCapitalManagementTrustPRO14Member">2014-03-31</rr:BarChartLowestQuarterlyReturnDate>
    <rr:YearToDateReturnLabel contextRef="S000007506_C000020486_D0630NorthCarolinaCapitalManagementTrustPRO14Member">Year-to-Date Return</rr:YearToDateReturnLabel>
    <rr:BarChartYearToDateReturn
      contextRef="S000007506_C000020486_D0630NorthCarolinaCapitalManagementTrustPRO14Member"
      decimals="4"
      unitRef="pure">0.0016</rr:BarChartYearToDateReturn>
    <rr:BarChartYearToDateReturnDate contextRef="S000007506_C000020486_D0630NorthCarolinaCapitalManagementTrustPRO14Member">2022-06-30</rr:BarChartYearToDateReturnDate>
    <rr:PerformanceTableHeading contextRef="S000007506_D0630NorthCarolinaCapitalManagementTrustPRO14Member">         Average Annual Returns

</rr:PerformanceTableHeading>
    <rr:AverageAnnualReturnLabel contextRef="S000007506_C000020486_ReturnBeforeTaxes_D0630NorthCarolinaCapitalManagementTrustPRO14Member">Government Portfolio</rr:AverageAnnualReturnLabel>
    <rr:AverageAnnualReturnYear01
      contextRef="S000007506_C000020486_ReturnBeforeTaxes_D0630NorthCarolinaCapitalManagementTrustPRO14Member"
      decimals="4"
      unitRef="pure">0.0001</rr:AverageAnnualReturnYear01>
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      contextRef="S000007506_C000020486_ReturnBeforeTaxes_D0630NorthCarolinaCapitalManagementTrustPRO14Member"
      decimals="4"
      unitRef="pure">0.0098</rr:AverageAnnualReturnYear05>
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      contextRef="S000007506_C000020486_ReturnBeforeTaxes_D0630NorthCarolinaCapitalManagementTrustPRO14Member"
      decimals="4"
      unitRef="pure">0.0054</rr:AverageAnnualReturnYear10>
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