Fair Value Measurements (Financial Instruments Measured at Fair Value on a Recurring Basis) (Details) (USD $) In Millions, unless otherwise specified
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Dec. 31, 2014
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Dec. 31, 2013
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Dec. 31, 2012
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Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
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Available-for-sale Securities |
$ 19.6us-gaap_AvailableForSaleSecurities |
$ 18.8us-gaap_AvailableForSaleSecurities |
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Trading Securities at Fair Value |
55.1us-gaap_TradingSecurities |
49.6us-gaap_TradingSecurities |
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Marketable Securities at Fair Value |
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68.4us-gaap_InvestmentsFairValueDisclosure |
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Investment Owned, at Fair Value |
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499.9us-gaap_InvestmentOwnedAtFairValue |
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Business Combination, Contingent Consideration, Liability |
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15.7us-gaap_BusinessCombinationContingentConsiderationLiability |
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Total liabilities at fair value |
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15.7us-gaap_LiabilitiesFairValueDisclosure |
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US Treasury Securities [Member] |
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Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
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Available-for-sale Securities |
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18.3us-gaap_AvailableForSaleSecurities / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USTreasurySecuritiesMember |
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Total Assets at Fair Value |
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568.3us-gaap_AssetsFairValueDisclosure / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USTreasurySecuritiesMember |
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Mutual funds [Member] |
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Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
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Trading Securities at Fair Value |
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49.6us-gaap_TradingSecurities / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = cme_MutualFundsMember |
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Asset-backed Securities [Member] |
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Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
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Available-for-sale Securities |
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0.4us-gaap_AvailableForSaleSecurities / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_AssetBackedSecuritiesMember |
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Domestic Corporate Debt Securities [Member] |
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Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
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Available-for-sale Securities |
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0.1us-gaap_AvailableForSaleSecurities / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_DomesticCorporateDebtSecuritiesMember |
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Fair Value, Inputs, level 1 [Member] |
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Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
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Marketable Securities at Fair Value |
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68.0us-gaap_InvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member |
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Investment Owned, at Fair Value |
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499.9us-gaap_InvestmentOwnedAtFairValue / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member |
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Business Combination, Contingent Consideration, Liability |
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0us-gaap_BusinessCombinationContingentConsiderationLiability / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member |
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Total liabilities at fair value |
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0us-gaap_LiabilitiesFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member |
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Fair Value, Inputs, level 1 [Member] | US Treasury Securities [Member] |
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Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
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Available-for-sale Securities |
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18.3us-gaap_AvailableForSaleSecurities / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USTreasurySecuritiesMember |
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Total Assets at Fair Value |
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567.9us-gaap_AssetsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USTreasurySecuritiesMember |
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Fair Value, Inputs, level 1 [Member] | Mutual funds [Member] |
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Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
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Trading Securities at Fair Value |
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49.6us-gaap_TradingSecurities / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = cme_MutualFundsMember |
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Fair Value, Inputs, level 1 [Member] | Asset-backed Securities [Member] |
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Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
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Available-for-sale Securities |
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0us-gaap_AvailableForSaleSecurities / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_AssetBackedSecuritiesMember |
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Fair Value, Inputs, level 1 [Member] | Domestic Corporate Debt Securities [Member] |
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Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
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Available-for-sale Securities |
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0.1us-gaap_AvailableForSaleSecurities / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_DomesticCorporateDebtSecuritiesMember |
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Fair Value, Inputs, level 2 [Member] |
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Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
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Marketable Securities at Fair Value |
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0.4us-gaap_InvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member |
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Investment Owned, at Fair Value |
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0us-gaap_InvestmentOwnedAtFairValue / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member |
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Business Combination, Contingent Consideration, Liability |
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0us-gaap_BusinessCombinationContingentConsiderationLiability / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member |
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Total liabilities at fair value |
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0us-gaap_LiabilitiesFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member |
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Fair Value, Inputs, level 2 [Member] | US Treasury Securities [Member] |
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Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
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Available-for-sale Securities |
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0us-gaap_AvailableForSaleSecurities / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USTreasurySecuritiesMember |
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Total Assets at Fair Value |
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0.4us-gaap_AssetsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USTreasurySecuritiesMember |
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Fair Value, Inputs, level 2 [Member] | Mutual funds [Member] |
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Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
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Trading Securities at Fair Value |
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0us-gaap_TradingSecurities / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = cme_MutualFundsMember |
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Fair Value, Inputs, level 2 [Member] | Asset-backed Securities [Member] |
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Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
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Available-for-sale Securities |
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0.4us-gaap_AvailableForSaleSecurities / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_AssetBackedSecuritiesMember |
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Fair Value, Inputs, level 2 [Member] | Domestic Corporate Debt Securities [Member] |
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Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
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Available-for-sale Securities |
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0us-gaap_AvailableForSaleSecurities / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_DomesticCorporateDebtSecuritiesMember |
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Fair Value, Inputs, level 3 [Member] |
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Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
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Marketable Securities at Fair Value |
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0us-gaap_InvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member |
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Investment Owned, at Fair Value |
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0us-gaap_InvestmentOwnedAtFairValue / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member |
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Business Combination, Contingent Consideration, Liability |
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15.7us-gaap_BusinessCombinationContingentConsiderationLiability / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member |
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Total liabilities at fair value |
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15.7us-gaap_LiabilitiesFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member |
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Fair Value, Inputs, level 3 [Member] | US Treasury Securities [Member] |
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Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
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Available-for-sale Securities |
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0us-gaap_AvailableForSaleSecurities / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USTreasurySecuritiesMember |
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Total Assets at Fair Value |
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0us-gaap_AssetsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USTreasurySecuritiesMember |
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Fair Value, Inputs, level 3 [Member] | Mutual funds [Member] |
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Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
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Trading Securities at Fair Value |
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0us-gaap_TradingSecurities / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = cme_MutualFundsMember |
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Fair Value, Inputs, level 3 [Member] | Asset-backed Securities [Member] |
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Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
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Available-for-sale Securities |
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0us-gaap_AvailableForSaleSecurities / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_AssetBackedSecuritiesMember |
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Fair Value, Inputs, level 3 [Member] | Domestic Corporate Debt Securities [Member] |
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Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
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Available-for-sale Securities |
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0us-gaap_AvailableForSaleSecurities / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_DomesticCorporateDebtSecuritiesMember |
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Fair Value, Measurements, Recurring [Member] |
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Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
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Marketable Securities at Fair Value |
74.7us-gaap_InvestmentsFairValueDisclosure / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |
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Investment Owned, at Fair Value |
432.1us-gaap_InvestmentOwnedAtFairValue / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |
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Total Assets at Fair Value |
17,206.5us-gaap_AssetsFairValueDisclosure / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |
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Derivative Liability, Fair Value, Gross Liability |
2.3us-gaap_DerivativeFairValueOfDerivativeLiability / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |
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Business Combination, Contingent Consideration, Liability |
17.7us-gaap_BusinessCombinationContingentConsiderationLiability / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |
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Total liabilities at fair value |
20.0us-gaap_LiabilitiesFairValueDisclosure / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |
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Fair Value, Measurements, Recurring [Member] | US Treasury Securities [Member] |
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Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
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Available-for-sale Securities |
19.1us-gaap_AvailableForSaleSecurities / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USTreasurySecuritiesMember |
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Fair Value, Measurements, Recurring [Member] | Mutual funds [Member] |
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Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
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Trading Securities at Fair Value |
55.1us-gaap_TradingSecurities / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = cme_MutualFundsMember |
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Fair Value, Measurements, Recurring [Member] | Equity Securities [Member] |
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Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
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Available-for-sale Securities |
0.1us-gaap_AvailableForSaleSecurities / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_EquitySecuritiesMember |
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Fair Value, Measurements, Recurring [Member] | Asset-backed Securities [Member] |
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Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
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Available-for-sale Securities |
0.4us-gaap_AvailableForSaleSecurities / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_AssetBackedSecuritiesMember |
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Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, level 1 [Member] |
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Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
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Marketable Securities at Fair Value |
74.3us-gaap_InvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |
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Investment Owned, at Fair Value |
432.1us-gaap_InvestmentOwnedAtFairValue / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |
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Total Assets at Fair Value |
17,206.1us-gaap_AssetsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |
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Derivative Liability, Fair Value, Gross Liability |
0us-gaap_DerivativeFairValueOfDerivativeLiability / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |
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Business Combination, Contingent Consideration, Liability |
0us-gaap_BusinessCombinationContingentConsiderationLiability / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |
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Total liabilities at fair value |
0us-gaap_LiabilitiesFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |
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Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, level 1 [Member] | US Treasury Securities [Member] |
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Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
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Available-for-sale Securities |
19.1us-gaap_AvailableForSaleSecurities / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USTreasurySecuritiesMember |
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Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, level 1 [Member] | Mutual funds [Member] |
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Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
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Trading Securities at Fair Value |
55.1us-gaap_TradingSecurities / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = cme_MutualFundsMember |
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Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, level 1 [Member] | Equity Securities [Member] |
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Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
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Available-for-sale Securities |
0.1us-gaap_AvailableForSaleSecurities / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_EquitySecuritiesMember |
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Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, level 1 [Member] | Asset-backed Securities [Member] |
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Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
|
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Available-for-sale Securities |
0us-gaap_AvailableForSaleSecurities / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_AssetBackedSecuritiesMember |
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Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, level 2 [Member] |
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Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
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Marketable Securities at Fair Value |
0.4us-gaap_InvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |
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Investment Owned, at Fair Value |
0us-gaap_InvestmentOwnedAtFairValue / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |
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Total Assets at Fair Value |
0.4us-gaap_AssetsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |
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Derivative Liability, Fair Value, Gross Liability |
2.3us-gaap_DerivativeFairValueOfDerivativeLiability / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |
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Business Combination, Contingent Consideration, Liability |
0us-gaap_BusinessCombinationContingentConsiderationLiability / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |
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Total liabilities at fair value |
2.3us-gaap_LiabilitiesFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |
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Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, level 2 [Member] | US Treasury Securities [Member] |
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Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
|
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Available-for-sale Securities |
0us-gaap_AvailableForSaleSecurities / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USTreasurySecuritiesMember |
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Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, level 2 [Member] | Mutual funds [Member] |
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Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
|
|
|
Trading Securities at Fair Value |
0us-gaap_TradingSecurities / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = cme_MutualFundsMember |
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Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, level 2 [Member] | Equity Securities [Member] |
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Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
|
|
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Available-for-sale Securities |
0us-gaap_AvailableForSaleSecurities / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_EquitySecuritiesMember |
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Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, level 2 [Member] | Asset-backed Securities [Member] |
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Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
|
|
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Available-for-sale Securities |
0.4us-gaap_AvailableForSaleSecurities / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_AssetBackedSecuritiesMember |
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Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, level 3 [Member] |
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Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
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Marketable Securities at Fair Value |
0us-gaap_InvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |
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Investment Owned, at Fair Value |
0us-gaap_InvestmentOwnedAtFairValue / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |
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Total Assets at Fair Value |
0us-gaap_AssetsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |
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Derivative Liability, Fair Value, Gross Liability |
0us-gaap_DerivativeFairValueOfDerivativeLiability / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |
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Business Combination, Contingent Consideration, Liability |
17.7us-gaap_BusinessCombinationContingentConsiderationLiability / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |
15.7us-gaap_BusinessCombinationContingentConsiderationLiability / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |
12.6us-gaap_BusinessCombinationContingentConsiderationLiability / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |
Total liabilities at fair value |
17.7us-gaap_LiabilitiesFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |
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Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, level 3 [Member] | US Treasury Securities [Member] |
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Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
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Available-for-sale Securities |
0us-gaap_AvailableForSaleSecurities / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USTreasurySecuritiesMember |
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Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, level 3 [Member] | Mutual funds [Member] |
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Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
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Trading Securities at Fair Value |
0us-gaap_TradingSecurities / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = cme_MutualFundsMember |
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Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, level 3 [Member] | Equity Securities [Member] |
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Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
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Available-for-sale Securities |
0us-gaap_AvailableForSaleSecurities / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_EquitySecuritiesMember |
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Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, level 3 [Member] | Asset-backed Securities [Member] |
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Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
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Available-for-sale Securities |
0us-gaap_AvailableForSaleSecurities / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_AssetBackedSecuritiesMember |
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U.S. Treasury Performance Bond [Member] |
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Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
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Available-for-sale Securities |
16,700.0us-gaap_AvailableForSaleSecurities / us-gaap_InvestmentTypeAxis = cme_U.S.TreasuryPerformanceBondMember |
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U.S. Treasury Performance Bond [Member] | Fair Value, Measurements, Recurring [Member] |
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Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
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Available-for-sale Securities |
16,699.7us-gaap_AvailableForSaleSecurities / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember / us-gaap_FinancialInstrumentAxis = cme_U.S.TreasuryPerformanceBondMember |
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U.S. Treasury Performance Bond [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, level 1 [Member] |
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Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
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Available-for-sale Securities |
16,699.7us-gaap_AvailableForSaleSecurities / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember / us-gaap_FinancialInstrumentAxis = cme_U.S.TreasuryPerformanceBondMember |
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U.S. Treasury Performance Bond [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, level 2 [Member] |
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Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
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Available-for-sale Securities |
0us-gaap_AvailableForSaleSecurities / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember / us-gaap_FinancialInstrumentAxis = cme_U.S.TreasuryPerformanceBondMember |
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U.S. Treasury Performance Bond [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, level 3 [Member] |
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Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
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Available-for-sale Securities |
$ 0us-gaap_AvailableForSaleSecurities / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember / us-gaap_FinancialInstrumentAxis = cme_U.S.TreasuryPerformanceBondMember |
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