v2.4.1.9

Condensed Consolidated Balance Sheet (Parenthetical) (USD $) In Millions, except Share data, unless otherwise specified | Mar. 31, 2015 | Dec. 31, 2014
--- | --- | ---
Preferred stock, authorized | 20,000,000 us-gaap_PreferredStockSharesAuthorized | 20,000,000 us-gaap_PreferredStockSharesAuthorized
Preferred stock, issued | 0 us-gaap_PreferredStockSharesIssued | 0 us-gaap_PreferredStockSharesIssued
Accumulated depreciation | $ 46,037 us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment | $ 45,410 us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment
Accumulated amortization | 10,507 us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization | 10,170 us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization
NBCUniversal Media, LLC [Member] |  |
Accumulated depreciation | 2,309 us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember | 2,167 us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember
Accumulated amortization | $ 5,027 us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember | $ 4,829 us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember
Class A Common Stock [Member] |  |
Common stock, par value | $ 0.01 us-gaap_CommonStockParOrStatedValuePerShare / us-gaap_StatementClassOfStockAxis = us-gaap_CommonClassAMember | $ 0.01 us-gaap_CommonStockParOrStatedValuePerShare / us-gaap_StatementClassOfStockAxis = us-gaap_CommonClassAMember
Common stock, authorized | 7,500,000,000 us-gaap_CommonStockSharesAuthorized / us-gaap_StatementClassOfStockAxis = us-gaap_CommonClassAMember | 7,500,000,000 us-gaap_CommonStockSharesAuthorized / us-gaap_StatementClassOfStockAxis = us-gaap_CommonClassAMember
Common stock, issued | 2,488,377,059 us-gaap_CommonStockSharesIssued / us-gaap_StatementClassOfStockAxis = us-gaap_CommonClassAMember | 2,496,598,612 us-gaap_CommonStockSharesIssued / us-gaap_StatementClassOfStockAxis = us-gaap_CommonClassAMember
Common stock, outstanding | 2,122,916,309 us-gaap_CommonStockSharesOutstanding / us-gaap_StatementClassOfStockAxis = us-gaap_CommonClassAMember | 2,131,137,862 us-gaap_CommonStockSharesOutstanding / us-gaap_StatementClassOfStockAxis = us-gaap_CommonClassAMember
Treasury stock common shares | 365,460,750 us-gaap_TreasuryStockShares / us-gaap_StatementClassOfStockAxis = us-gaap_CommonClassAMember | 365,460,750 us-gaap_TreasuryStockShares / us-gaap_StatementClassOfStockAxis = us-gaap_CommonClassAMember
Class A Special Common Stock [Member] |  |
Common stock, par value | $ 0.01 us-gaap_CommonStockParOrStatedValuePerShare / us-gaap_StatementClassOfStockAxis = cmcsa_ClassaSpecialCommonStockMember | $ 0.01 us-gaap_CommonStockParOrStatedValuePerShare / us-gaap_StatementClassOfStockAxis = cmcsa_ClassaSpecialCommonStockMember
Common stock, authorized | 7,500,000,000 us-gaap_CommonStockSharesAuthorized / us-gaap_StatementClassOfStockAxis = cmcsa_ClassaSpecialCommonStockMember | 7,500,000,000 us-gaap_CommonStockSharesAuthorized / us-gaap_StatementClassOfStockAxis = cmcsa_ClassaSpecialCommonStockMember
Common stock, issued | 452,117,242 us-gaap_CommonStockSharesIssued / us-gaap_StatementClassOfStockAxis = cmcsa_ClassaSpecialCommonStockMember | 471,419,601 us-gaap_CommonStockSharesIssued / us-gaap_StatementClassOfStockAxis = cmcsa_ClassaSpecialCommonStockMember
Common stock, outstanding | 381,182,478 us-gaap_CommonStockSharesOutstanding / us-gaap_StatementClassOfStockAxis = cmcsa_ClassaSpecialCommonStockMember | 400,484,837 us-gaap_CommonStockSharesOutstanding / us-gaap_StatementClassOfStockAxis = cmcsa_ClassaSpecialCommonStockMember
Treasury stock common shares | 70,934,764 us-gaap_TreasuryStockShares / us-gaap_StatementClassOfStockAxis = cmcsa_ClassaSpecialCommonStockMember | 70,934,764 us-gaap_TreasuryStockShares / us-gaap_StatementClassOfStockAxis = cmcsa_ClassaSpecialCommonStockMember
Class B Common Stock [Member] |  |
Common stock, par value | $ 0.01 us-gaap_CommonStockParOrStatedValuePerShare / us-gaap_StatementClassOfStockAxis = us-gaap_CommonClassBMember | $ 0.01 us-gaap_CommonStockParOrStatedValuePerShare / us-gaap_StatementClassOfStockAxis = us-gaap_CommonClassBMember
Common stock, authorized | 75,000,000 us-gaap_CommonStockSharesAuthorized / us-gaap_StatementClassOfStockAxis = us-gaap_CommonClassBMember | 75,000,000 us-gaap_CommonStockSharesAuthorized / us-gaap_StatementClassOfStockAxis = us-gaap_CommonClassBMember
Common stock, issued | 9,444,375 us-gaap_CommonStockSharesIssued / us-gaap_StatementClassOfStockAxis = us-gaap_CommonClassBMember | 9,444,375 us-gaap_CommonStockSharesIssued / us-gaap_StatementClassOfStockAxis = us-gaap_CommonClassBMember
Common stock, outstanding | 9,444,375 us-gaap_CommonStockSharesOutstanding / us-gaap_StatementClassOfStockAxis = us-gaap_CommonClassBMember | 9,444,375 us-gaap_CommonStockSharesOutstanding / us-gaap_StatementClassOfStockAxis = us-gaap_CommonClassBMember

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