v2.4.1.9

Financial Data by Business Segment (Details) (USD $) | 3 Months Ended
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Mar. 31, 2015 | Mar. 31, 2014
Revenue | $ 17,853,000,000 us-gaap_Revenues | $ 17,408,000,000 us-gaap_Revenues
Operating income (loss) before depreciation and amortization | 5,956,000,000 cmcsa_OperatingIncomeExcludingDepreciationAndAmortization | 5,538,000,000 cmcsa_OperatingIncomeExcludingDepreciationAndAmortization
Depreciation and amortization | 2,066,000,000 us-gaap_DepreciationAndAmortization | 1,970,000,000 us-gaap_DepreciationAndAmortization
Operating income (loss) | 3,890,000,000 us-gaap_OperatingIncomeLoss | 3,568,000,000 us-gaap_OperatingIncomeLoss
Capital expenditures | 1,726,000,000 us-gaap_PaymentsToAcquirePropertyPlantAndEquipment | 1,448,000,000 us-gaap_PaymentsToAcquirePropertyPlantAndEquipment
NBCUniversal Media, LLC [Member] |  |
Revenue | 6,604,000,000 us-gaap_Revenues / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember | 6,876,000,000 us-gaap_Revenues / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember
Operating income (loss) before depreciation and amortization | 1,494,000,000 cmcsa_OperatingIncomeExcludingDepreciationAndAmortization / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember | 1,311,000,000 cmcsa_OperatingIncomeExcludingDepreciationAndAmortization / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember
Depreciation and amortization | 364,000,000 us-gaap_DepreciationAndAmortization / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember | 365,000,000 us-gaap_DepreciationAndAmortization / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember
Operating income (loss) | 1,130,000,000 us-gaap_OperatingIncomeLoss / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember | 946,000,000 us-gaap_OperatingIncomeLoss / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember
Capital expenditures | 268,000,000 us-gaap_PaymentsToAcquirePropertyPlantAndEquipment / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember | 291,000,000 us-gaap_PaymentsToAcquirePropertyPlantAndEquipment / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember
Cable Communications [Member] |  |
Revenue | 11,430,000,000 us-gaap_Revenues / us-gaap_StatementBusinessSegmentsAxis = cmcsa_CableCommunicationsMember | 10,757,000,000 us-gaap_Revenues / us-gaap_StatementBusinessSegmentsAxis = cmcsa_CableCommunicationsMember
Operating income (loss) before depreciation and amortization | 4,674,000,000 cmcsa_OperatingIncomeExcludingDepreciationAndAmortization / us-gaap_StatementBusinessSegmentsAxis = cmcsa_CableCommunicationsMember | 4,400,000,000 cmcsa_OperatingIncomeExcludingDepreciationAndAmortization / us-gaap_StatementBusinessSegmentsAxis = cmcsa_CableCommunicationsMember
Depreciation and amortization | 1,675,000,000 us-gaap_DepreciationAndAmortization / us-gaap_StatementBusinessSegmentsAxis = cmcsa_CableCommunicationsMember | 1,584,000,000 us-gaap_DepreciationAndAmortization / us-gaap_StatementBusinessSegmentsAxis = cmcsa_CableCommunicationsMember
Operating income (loss) | 2,999,000,000 us-gaap_OperatingIncomeLoss / us-gaap_StatementBusinessSegmentsAxis = cmcsa_CableCommunicationsMember | 2,816,000,000 us-gaap_OperatingIncomeLoss / us-gaap_StatementBusinessSegmentsAxis = cmcsa_CableCommunicationsMember
Capital expenditures | 1,445,000,000 us-gaap_PaymentsToAcquirePropertyPlantAndEquipment / us-gaap_StatementBusinessSegmentsAxis = cmcsa_CableCommunicationsMember | 1,145,000,000 us-gaap_PaymentsToAcquirePropertyPlantAndEquipment / us-gaap_StatementBusinessSegmentsAxis = cmcsa_CableCommunicationsMember
Cable segment revenue types as percentage of total cable revenue | 100.00%cmcsa_CableSegmentRevenueTypesAsPercentageOfTotalCableRevenue / us-gaap_StatementBusinessSegmentsAxis = cmcsa_CableCommunicationsMember | 100.00%cmcsa_CableSegmentRevenueTypesAsPercentageOfTotalCableRevenue / us-gaap_StatementBusinessSegmentsAxis = cmcsa_CableCommunicationsMember
Cable Networks [Member] |  |
Revenue | 2,359,000,000 us-gaap_Revenues / us-gaap_StatementBusinessSegmentsAxis = cmcsa_CableNetworksMember | 2,505,000,000 us-gaap_Revenues / us-gaap_StatementBusinessSegmentsAxis = cmcsa_CableNetworksMember
Operating income (loss) before depreciation and amortization | 898,000,000 cmcsa_OperatingIncomeExcludingDepreciationAndAmortization / us-gaap_StatementBusinessSegmentsAxis = cmcsa_CableNetworksMember | 895,000,000 cmcsa_OperatingIncomeExcludingDepreciationAndAmortization / us-gaap_StatementBusinessSegmentsAxis = cmcsa_CableNetworksMember
Depreciation and amortization | 184,000,000 us-gaap_DepreciationAndAmortization / us-gaap_StatementBusinessSegmentsAxis = cmcsa_CableNetworksMember | 189,000,000 us-gaap_DepreciationAndAmortization / us-gaap_StatementBusinessSegmentsAxis = cmcsa_CableNetworksMember
Operating income (loss) | 714,000,000 us-gaap_OperatingIncomeLoss / us-gaap_StatementBusinessSegmentsAxis = cmcsa_CableNetworksMember | 706,000,000 us-gaap_OperatingIncomeLoss / us-gaap_StatementBusinessSegmentsAxis = cmcsa_CableNetworksMember
Capital expenditures | 6,000,000 us-gaap_PaymentsToAcquirePropertyPlantAndEquipment / us-gaap_StatementBusinessSegmentsAxis = cmcsa_CableNetworksMember | 11,000,000 us-gaap_PaymentsToAcquirePropertyPlantAndEquipment / us-gaap_StatementBusinessSegmentsAxis = cmcsa_CableNetworksMember
Cable Networks [Member] | NBCUniversal Media, LLC [Member] |  |
Revenue | 2,359,000,000 us-gaap_Revenues / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementBusinessSegmentsAxis = cmcsa_CableNetworksMember | 2,505,000,000 us-gaap_Revenues / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementBusinessSegmentsAxis = cmcsa_CableNetworksMember
Operating income (loss) before depreciation and amortization | 898,000,000 cmcsa_OperatingIncomeExcludingDepreciationAndAmortization / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementBusinessSegmentsAxis = cmcsa_CableNetworksMember | 895,000,000 cmcsa_OperatingIncomeExcludingDepreciationAndAmortization / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementBusinessSegmentsAxis = cmcsa_CableNetworksMember
Depreciation and amortization | 184,000,000 us-gaap_DepreciationAndAmortization / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementBusinessSegmentsAxis = cmcsa_CableNetworksMember | 189,000,000 us-gaap_DepreciationAndAmortization / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementBusinessSegmentsAxis = cmcsa_CableNetworksMember
Operating income (loss) | 714,000,000 us-gaap_OperatingIncomeLoss / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementBusinessSegmentsAxis = cmcsa_CableNetworksMember | 706,000,000 us-gaap_OperatingIncomeLoss / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementBusinessSegmentsAxis = cmcsa_CableNetworksMember
Capital expenditures | 6,000,000 us-gaap_PaymentsToAcquirePropertyPlantAndEquipment / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementBusinessSegmentsAxis = cmcsa_CableNetworksMember | 11,000,000 us-gaap_PaymentsToAcquirePropertyPlantAndEquipment / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementBusinessSegmentsAxis = cmcsa_CableNetworksMember
Broadcast Television [Member] |  |
Revenue | 2,248,000,000 us-gaap_Revenues / us-gaap_StatementBusinessSegmentsAxis = cmcsa_BroadcastTelevisionMember | 2,621,000,000 us-gaap_Revenues / us-gaap_StatementBusinessSegmentsAxis = cmcsa_BroadcastTelevisionMember
Operating income (loss) before depreciation and amortization | 182,000,000 cmcsa_OperatingIncomeExcludingDepreciationAndAmortization / us-gaap_StatementBusinessSegmentsAxis = cmcsa_BroadcastTelevisionMember | 122,000,000 cmcsa_OperatingIncomeExcludingDepreciationAndAmortization / us-gaap_StatementBusinessSegmentsAxis = cmcsa_BroadcastTelevisionMember
Depreciation and amortization | 29,000,000 us-gaap_DepreciationAndAmortization / us-gaap_StatementBusinessSegmentsAxis = cmcsa_BroadcastTelevisionMember | 27,000,000 us-gaap_DepreciationAndAmortization / us-gaap_StatementBusinessSegmentsAxis = cmcsa_BroadcastTelevisionMember
Operating income (loss) | 153,000,000 us-gaap_OperatingIncomeLoss / us-gaap_StatementBusinessSegmentsAxis = cmcsa_BroadcastTelevisionMember | 95,000,000 us-gaap_OperatingIncomeLoss / us-gaap_StatementBusinessSegmentsAxis = cmcsa_BroadcastTelevisionMember
Capital expenditures | 11,000,000 us-gaap_PaymentsToAcquirePropertyPlantAndEquipment / us-gaap_StatementBusinessSegmentsAxis = cmcsa_BroadcastTelevisionMember | 11,000,000 us-gaap_PaymentsToAcquirePropertyPlantAndEquipment / us-gaap_StatementBusinessSegmentsAxis = cmcsa_BroadcastTelevisionMember
Broadcast Television [Member] | NBCUniversal Media, LLC [Member] |  |
Revenue | 2,248,000,000 us-gaap_Revenues / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementBusinessSegmentsAxis = cmcsa_BroadcastTelevisionMember | 2,621,000,000 us-gaap_Revenues / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementBusinessSegmentsAxis = cmcsa_BroadcastTelevisionMember
Operating income (loss) before depreciation and amortization | 182,000,000 cmcsa_OperatingIncomeExcludingDepreciationAndAmortization / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementBusinessSegmentsAxis = cmcsa_BroadcastTelevisionMember | 122,000,000 cmcsa_OperatingIncomeExcludingDepreciationAndAmortization / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementBusinessSegmentsAxis = cmcsa_BroadcastTelevisionMember
Depreciation and amortization | 29,000,000 us-gaap_DepreciationAndAmortization / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementBusinessSegmentsAxis = cmcsa_BroadcastTelevisionMember | 27,000,000 us-gaap_DepreciationAndAmortization / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementBusinessSegmentsAxis = cmcsa_BroadcastTelevisionMember
Operating income (loss) | 153,000,000 us-gaap_OperatingIncomeLoss / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementBusinessSegmentsAxis = cmcsa_BroadcastTelevisionMember | 95,000,000 us-gaap_OperatingIncomeLoss / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementBusinessSegmentsAxis = cmcsa_BroadcastTelevisionMember
Capital expenditures | 11,000,000 us-gaap_PaymentsToAcquirePropertyPlantAndEquipment / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementBusinessSegmentsAxis = cmcsa_BroadcastTelevisionMember | 11,000,000 us-gaap_PaymentsToAcquirePropertyPlantAndEquipment / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementBusinessSegmentsAxis = cmcsa_BroadcastTelevisionMember
Filmed Entertainment [Member] |  |
Revenue | 1,446,000,000 us-gaap_Revenues / us-gaap_StatementBusinessSegmentsAxis = cmcsa_FilmedEntertainmentMember | 1,351,000,000 us-gaap_Revenues / us-gaap_StatementBusinessSegmentsAxis = cmcsa_FilmedEntertainmentMember
Operating income (loss) before depreciation and amortization | 293,000,000 cmcsa_OperatingIncomeExcludingDepreciationAndAmortization / us-gaap_StatementBusinessSegmentsAxis = cmcsa_FilmedEntertainmentMember | 288,000,000 cmcsa_OperatingIncomeExcludingDepreciationAndAmortization / us-gaap_StatementBusinessSegmentsAxis = cmcsa_FilmedEntertainmentMember
Depreciation and amortization | 5,000,000 us-gaap_DepreciationAndAmortization / us-gaap_StatementBusinessSegmentsAxis = cmcsa_FilmedEntertainmentMember | 5,000,000 us-gaap_DepreciationAndAmortization / us-gaap_StatementBusinessSegmentsAxis = cmcsa_FilmedEntertainmentMember
Operating income (loss) | 288,000,000 us-gaap_OperatingIncomeLoss / us-gaap_StatementBusinessSegmentsAxis = cmcsa_FilmedEntertainmentMember | 283,000,000 us-gaap_OperatingIncomeLoss / us-gaap_StatementBusinessSegmentsAxis = cmcsa_FilmedEntertainmentMember
Capital expenditures | 1,000,000 us-gaap_PaymentsToAcquirePropertyPlantAndEquipment / us-gaap_StatementBusinessSegmentsAxis = cmcsa_FilmedEntertainmentMember | 1,000,000 us-gaap_PaymentsToAcquirePropertyPlantAndEquipment / us-gaap_StatementBusinessSegmentsAxis = cmcsa_FilmedEntertainmentMember
Filmed Entertainment [Member] | NBCUniversal Media, LLC [Member] |  |
Revenue | 1,446,000,000 us-gaap_Revenues / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementBusinessSegmentsAxis = cmcsa_FilmedEntertainmentMember | 1,351,000,000 us-gaap_Revenues / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementBusinessSegmentsAxis = cmcsa_FilmedEntertainmentMember
Operating income (loss) before depreciation and amortization | 293,000,000 cmcsa_OperatingIncomeExcludingDepreciationAndAmortization / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementBusinessSegmentsAxis = cmcsa_FilmedEntertainmentMember | 288,000,000 cmcsa_OperatingIncomeExcludingDepreciationAndAmortization / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementBusinessSegmentsAxis = cmcsa_FilmedEntertainmentMember
Depreciation and amortization | 5,000,000 us-gaap_DepreciationAndAmortization / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementBusinessSegmentsAxis = cmcsa_FilmedEntertainmentMember | 5,000,000 us-gaap_DepreciationAndAmortization / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementBusinessSegmentsAxis = cmcsa_FilmedEntertainmentMember
Operating income (loss) | 288,000,000 us-gaap_OperatingIncomeLoss / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementBusinessSegmentsAxis = cmcsa_FilmedEntertainmentMember | 283,000,000 us-gaap_OperatingIncomeLoss / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementBusinessSegmentsAxis = cmcsa_FilmedEntertainmentMember
Capital expenditures | 1,000,000 us-gaap_PaymentsToAcquirePropertyPlantAndEquipment / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementBusinessSegmentsAxis = cmcsa_FilmedEntertainmentMember | 1,000,000 us-gaap_PaymentsToAcquirePropertyPlantAndEquipment / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementBusinessSegmentsAxis = cmcsa_FilmedEntertainmentMember
Theme Parks [Member] |  |
Revenue | 651,000,000 us-gaap_Revenues / us-gaap_StatementBusinessSegmentsAxis = cmcsa_ThemeParksMember | 487,000,000 us-gaap_Revenues / us-gaap_StatementBusinessSegmentsAxis = cmcsa_ThemeParksMember
Operating income (loss) before depreciation and amortization | 263,000,000 cmcsa_OperatingIncomeExcludingDepreciationAndAmortization / us-gaap_StatementBusinessSegmentsAxis = cmcsa_ThemeParksMember | 170,000,000 cmcsa_OperatingIncomeExcludingDepreciationAndAmortization / us-gaap_StatementBusinessSegmentsAxis = cmcsa_ThemeParksMember
Depreciation and amortization | 66,000,000 us-gaap_DepreciationAndAmortization / us-gaap_StatementBusinessSegmentsAxis = cmcsa_ThemeParksMember | 69,000,000 us-gaap_DepreciationAndAmortization / us-gaap_StatementBusinessSegmentsAxis = cmcsa_ThemeParksMember
Operating income (loss) | 197,000,000 us-gaap_OperatingIncomeLoss / us-gaap_StatementBusinessSegmentsAxis = cmcsa_ThemeParksMember | 101,000,000 us-gaap_OperatingIncomeLoss / us-gaap_StatementBusinessSegmentsAxis = cmcsa_ThemeParksMember
Capital expenditures | 162,000,000 us-gaap_PaymentsToAcquirePropertyPlantAndEquipment / us-gaap_StatementBusinessSegmentsAxis = cmcsa_ThemeParksMember | 144,000,000 us-gaap_PaymentsToAcquirePropertyPlantAndEquipment / us-gaap_StatementBusinessSegmentsAxis = cmcsa_ThemeParksMember
Theme Parks [Member] | NBCUniversal Media, LLC [Member] |  |
Revenue | 651,000,000 us-gaap_Revenues / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementBusinessSegmentsAxis = cmcsa_ThemeParksMember | 487,000,000 us-gaap_Revenues / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementBusinessSegmentsAxis = cmcsa_ThemeParksMember
Operating income (loss) before depreciation and amortization | 263,000,000 cmcsa_OperatingIncomeExcludingDepreciationAndAmortization / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementBusinessSegmentsAxis = cmcsa_ThemeParksMember | 170,000,000 cmcsa_OperatingIncomeExcludingDepreciationAndAmortization / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementBusinessSegmentsAxis = cmcsa_ThemeParksMember
Depreciation and amortization | 66,000,000 us-gaap_DepreciationAndAmortization / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementBusinessSegmentsAxis = cmcsa_ThemeParksMember | 69,000,000 us-gaap_DepreciationAndAmortization / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementBusinessSegmentsAxis = cmcsa_ThemeParksMember
Operating income (loss) | 197,000,000 us-gaap_OperatingIncomeLoss / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementBusinessSegmentsAxis = cmcsa_ThemeParksMember | 101,000,000 us-gaap_OperatingIncomeLoss / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementBusinessSegmentsAxis = cmcsa_ThemeParksMember
Capital expenditures | 162,000,000 us-gaap_PaymentsToAcquirePropertyPlantAndEquipment / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementBusinessSegmentsAxis = cmcsa_ThemeParksMember | 144,000,000 us-gaap_PaymentsToAcquirePropertyPlantAndEquipment / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementBusinessSegmentsAxis = cmcsa_ThemeParksMember
Headquarters And Other [Member] |  |
Revenue | 4,000,000 us-gaap_Revenues / us-gaap_StatementBusinessSegmentsAxis = cmcsa_HeadquartersAndOtherMember | 2,000,000 us-gaap_Revenues / us-gaap_StatementBusinessSegmentsAxis = cmcsa_HeadquartersAndOtherMember
Operating income (loss) before depreciation and amortization | (140,000,000)cmcsa_OperatingIncomeExcludingDepreciationAndAmortization / us-gaap_StatementBusinessSegmentsAxis = cmcsa_HeadquartersAndOtherMember | (163,000,000)cmcsa_OperatingIncomeExcludingDepreciationAndAmortization / us-gaap_StatementBusinessSegmentsAxis = cmcsa_HeadquartersAndOtherMember
Depreciation and amortization | 80,000,000 us-gaap_DepreciationAndAmortization / us-gaap_StatementBusinessSegmentsAxis = cmcsa_HeadquartersAndOtherMember | 75,000,000 us-gaap_DepreciationAndAmortization / us-gaap_StatementBusinessSegmentsAxis = cmcsa_HeadquartersAndOtherMember
Operating income (loss) | (220,000,000)us-gaap_OperatingIncomeLoss / us-gaap_StatementBusinessSegmentsAxis = cmcsa_HeadquartersAndOtherMember | (238,000,000)us-gaap_OperatingIncomeLoss / us-gaap_StatementBusinessSegmentsAxis = cmcsa_HeadquartersAndOtherMember
Capital expenditures | 88,000,000 us-gaap_PaymentsToAcquirePropertyPlantAndEquipment / us-gaap_StatementBusinessSegmentsAxis = cmcsa_HeadquartersAndOtherMember | 124,000,000 us-gaap_PaymentsToAcquirePropertyPlantAndEquipment / us-gaap_StatementBusinessSegmentsAxis = cmcsa_HeadquartersAndOtherMember
Headquarters And Other [Member] | NBCUniversal Media, LLC [Member] |  |
Revenue | 4,000,000 us-gaap_Revenues / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementBusinessSegmentsAxis = cmcsa_HeadquartersAndOtherMember | 2,000,000 us-gaap_Revenues / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementBusinessSegmentsAxis = cmcsa_HeadquartersAndOtherMember
Operating income (loss) before depreciation and amortization | (140,000,000)cmcsa_OperatingIncomeExcludingDepreciationAndAmortization / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementBusinessSegmentsAxis = cmcsa_HeadquartersAndOtherMember | (163,000,000)cmcsa_OperatingIncomeExcludingDepreciationAndAmortization / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementBusinessSegmentsAxis = cmcsa_HeadquartersAndOtherMember
Depreciation and amortization | 80,000,000 us-gaap_DepreciationAndAmortization / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementBusinessSegmentsAxis = cmcsa_HeadquartersAndOtherMember | 75,000,000 us-gaap_DepreciationAndAmortization / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementBusinessSegmentsAxis = cmcsa_HeadquartersAndOtherMember
Operating income (loss) | (220,000,000)us-gaap_OperatingIncomeLoss / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementBusinessSegmentsAxis = cmcsa_HeadquartersAndOtherMember | (238,000,000)us-gaap_OperatingIncomeLoss / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementBusinessSegmentsAxis = cmcsa_HeadquartersAndOtherMember
Capital expenditures | 88,000,000 us-gaap_PaymentsToAcquirePropertyPlantAndEquipment / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementBusinessSegmentsAxis = cmcsa_HeadquartersAndOtherMember | 124,000,000 us-gaap_PaymentsToAcquirePropertyPlantAndEquipment / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementBusinessSegmentsAxis = cmcsa_HeadquartersAndOtherMember
NBCUniversal Eliminations [Member] |  |
Revenue | (104,000,000)us-gaap_Revenues / us-gaap_StatementBusinessSegmentsAxis = cmcsa_NbcuniversalEliminationsMember | (90,000,000)us-gaap_Revenues / us-gaap_StatementBusinessSegmentsAxis = cmcsa_NbcuniversalEliminationsMember
Operating income (loss) before depreciation and amortization | (2,000,000)cmcsa_OperatingIncomeExcludingDepreciationAndAmortization / us-gaap_StatementBusinessSegmentsAxis = cmcsa_NbcuniversalEliminationsMember | (1,000,000)cmcsa_OperatingIncomeExcludingDepreciationAndAmortization / us-gaap_StatementBusinessSegmentsAxis = cmcsa_NbcuniversalEliminationsMember
Depreciation and amortization | 0 us-gaap_DepreciationAndAmortization / us-gaap_StatementBusinessSegmentsAxis = cmcsa_NbcuniversalEliminationsMember | 0 us-gaap_DepreciationAndAmortization / us-gaap_StatementBusinessSegmentsAxis = cmcsa_NbcuniversalEliminationsMember
Operating income (loss) | (2,000,000)us-gaap_OperatingIncomeLoss / us-gaap_StatementBusinessSegmentsAxis = cmcsa_NbcuniversalEliminationsMember | (1,000,000)us-gaap_OperatingIncomeLoss / us-gaap_StatementBusinessSegmentsAxis = cmcsa_NbcuniversalEliminationsMember
Capital expenditures | 0 us-gaap_PaymentsToAcquirePropertyPlantAndEquipment / us-gaap_StatementBusinessSegmentsAxis = cmcsa_NbcuniversalEliminationsMember | 0 us-gaap_PaymentsToAcquirePropertyPlantAndEquipment / us-gaap_StatementBusinessSegmentsAxis = cmcsa_NbcuniversalEliminationsMember
NBCUniversal Eliminations [Member] | NBCUniversal Media, LLC [Member] |  |
Revenue | (104,000,000)us-gaap_Revenues / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementBusinessSegmentsAxis = cmcsa_NbcuniversalEliminationsMember | (90,000,000)us-gaap_Revenues / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementBusinessSegmentsAxis = cmcsa_NbcuniversalEliminationsMember
Operating income (loss) before depreciation and amortization | (2,000,000)cmcsa_OperatingIncomeExcludingDepreciationAndAmortization / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementBusinessSegmentsAxis = cmcsa_NbcuniversalEliminationsMember | (1,000,000)cmcsa_OperatingIncomeExcludingDepreciationAndAmortization / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementBusinessSegmentsAxis = cmcsa_NbcuniversalEliminationsMember
Depreciation and amortization | 0 us-gaap_DepreciationAndAmortization / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementBusinessSegmentsAxis = cmcsa_NbcuniversalEliminationsMember | 0 us-gaap_DepreciationAndAmortization / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementBusinessSegmentsAxis = cmcsa_NbcuniversalEliminationsMember
Operating income (loss) | (2,000,000)us-gaap_OperatingIncomeLoss / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementBusinessSegmentsAxis = cmcsa_NbcuniversalEliminationsMember | (1,000,000)us-gaap_OperatingIncomeLoss / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementBusinessSegmentsAxis = cmcsa_NbcuniversalEliminationsMember
Capital expenditures | 0 us-gaap_PaymentsToAcquirePropertyPlantAndEquipment / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementBusinessSegmentsAxis = cmcsa_NbcuniversalEliminationsMember | 0 us-gaap_PaymentsToAcquirePropertyPlantAndEquipment / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementBusinessSegmentsAxis = cmcsa_NbcuniversalEliminationsMember
NBCUniversal [Member] |  |
Revenue | 6,604,000,000 us-gaap_Revenues / us-gaap_StatementBusinessSegmentsAxis = cmcsa_NbcuniversalMember | 6,876,000,000 us-gaap_Revenues / us-gaap_StatementBusinessSegmentsAxis = cmcsa_NbcuniversalMember
Operating income (loss) before depreciation and amortization | 1,494,000,000 cmcsa_OperatingIncomeExcludingDepreciationAndAmortization / us-gaap_StatementBusinessSegmentsAxis = cmcsa_NbcuniversalMember | 1,311,000,000 cmcsa_OperatingIncomeExcludingDepreciationAndAmortization / us-gaap_StatementBusinessSegmentsAxis = cmcsa_NbcuniversalMember
Depreciation and amortization | 364,000,000 us-gaap_DepreciationAndAmortization / us-gaap_StatementBusinessSegmentsAxis = cmcsa_NbcuniversalMember | 365,000,000 us-gaap_DepreciationAndAmortization / us-gaap_StatementBusinessSegmentsAxis = cmcsa_NbcuniversalMember
Operating income (loss) | 1,130,000,000 us-gaap_OperatingIncomeLoss / us-gaap_StatementBusinessSegmentsAxis = cmcsa_NbcuniversalMember | 946,000,000 us-gaap_OperatingIncomeLoss / us-gaap_StatementBusinessSegmentsAxis = cmcsa_NbcuniversalMember
Capital expenditures | 268,000,000 us-gaap_PaymentsToAcquirePropertyPlantAndEquipment / us-gaap_StatementBusinessSegmentsAxis = cmcsa_NbcuniversalMember | 291,000,000 us-gaap_PaymentsToAcquirePropertyPlantAndEquipment / us-gaap_StatementBusinessSegmentsAxis = cmcsa_NbcuniversalMember
Corporate and Other [Member] |  |
Revenue | 204,000,000 us-gaap_Revenues / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateAndOtherMember | 174,000,000 us-gaap_Revenues / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateAndOtherMember
Operating income (loss) before depreciation and amortization | (225,000,000)cmcsa_OperatingIncomeExcludingDepreciationAndAmortization / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateAndOtherMember | (153,000,000)cmcsa_OperatingIncomeExcludingDepreciationAndAmortization / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateAndOtherMember
Depreciation and amortization | 27,000,000 us-gaap_DepreciationAndAmortization / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateAndOtherMember | 21,000,000 us-gaap_DepreciationAndAmortization / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateAndOtherMember
Operating income (loss) | (252,000,000)us-gaap_OperatingIncomeLoss / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateAndOtherMember | (174,000,000)us-gaap_OperatingIncomeLoss / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateAndOtherMember
Capital expenditures | 13,000,000 us-gaap_PaymentsToAcquirePropertyPlantAndEquipment / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateAndOtherMember | 12,000,000 us-gaap_PaymentsToAcquirePropertyPlantAndEquipment / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateAndOtherMember
Eliminations [Member] |  |
Revenue | (385,000,000)us-gaap_Revenues / us-gaap_StatementBusinessSegmentsAxis = cmcsa_EliminationsMember | (399,000,000)us-gaap_Revenues / us-gaap_StatementBusinessSegmentsAxis = cmcsa_EliminationsMember
Operating income (loss) before depreciation and amortization | 13,000,000 cmcsa_OperatingIncomeExcludingDepreciationAndAmortization / us-gaap_StatementBusinessSegmentsAxis = cmcsa_EliminationsMember | (20,000,000)cmcsa_OperatingIncomeExcludingDepreciationAndAmortization / us-gaap_StatementBusinessSegmentsAxis = cmcsa_EliminationsMember
Depreciation and amortization | 0 us-gaap_DepreciationAndAmortization / us-gaap_StatementBusinessSegmentsAxis = cmcsa_EliminationsMember | 0 us-gaap_DepreciationAndAmortization / us-gaap_StatementBusinessSegmentsAxis = cmcsa_EliminationsMember
Operating income (loss) | 13,000,000 us-gaap_OperatingIncomeLoss / us-gaap_StatementBusinessSegmentsAxis = cmcsa_EliminationsMember | (20,000,000)us-gaap_OperatingIncomeLoss / us-gaap_StatementBusinessSegmentsAxis = cmcsa_EliminationsMember
Capital expenditures | $ 0 us-gaap_PaymentsToAcquirePropertyPlantAndEquipment / us-gaap_StatementBusinessSegmentsAxis = cmcsa_EliminationsMember | $ 0 us-gaap_PaymentsToAcquirePropertyPlantAndEquipment / us-gaap_StatementBusinessSegmentsAxis = cmcsa_EliminationsMember
Cable Communications Segment Revenue Percentage-Video [Member] |  |
Cable segment revenue types as percentage of total cable revenue | 46.60%cmcsa_CableSegmentRevenueTypesAsPercentageOfTotalCableRevenue / us-gaap_StatementBusinessSegmentsAxis = cmcsa_CableCommunicationsSegmentRevenuePercentageVideoMember | 48.10%cmcsa_CableSegmentRevenueTypesAsPercentageOfTotalCableRevenue / us-gaap_StatementBusinessSegmentsAxis = cmcsa_CableCommunicationsSegmentRevenuePercentageVideoMember
Cable Communications Segment Revenue Percentage - High-speed Internet [Member] |  |
Cable segment revenue types as percentage of total cable revenue | 26.60%cmcsa_CableSegmentRevenueTypesAsPercentageOfTotalCableRevenue / us-gaap_StatementBusinessSegmentsAxis = cmcsa_CableCommunicationsSegmentRevenuePercentageHighSpeedInternetMember | 25.60%cmcsa_CableSegmentRevenueTypesAsPercentageOfTotalCableRevenue / us-gaap_StatementBusinessSegmentsAxis = cmcsa_CableCommunicationsSegmentRevenuePercentageHighSpeedInternetMember
Cable Communications Segment Revenue Percentage- Voice [Member] |  |
Cable segment revenue types as percentage of total cable revenue | 7.90%cmcsa_CableSegmentRevenueTypesAsPercentageOfTotalCableRevenue / us-gaap_StatementBusinessSegmentsAxis = cmcsa_CableCommunicationsSegmentRevenuePercentageVoiceMember | 8.50%cmcsa_CableSegmentRevenueTypesAsPercentageOfTotalCableRevenue / us-gaap_StatementBusinessSegmentsAxis = cmcsa_CableCommunicationsSegmentRevenuePercentageVoiceMember
Cable Communications Segment Revenue Percentage- Business Services [Member] |  |
Cable segment revenue types as percentage of total cable revenue | 9.70%cmcsa_CableSegmentRevenueTypesAsPercentageOfTotalCableRevenue / us-gaap_StatementBusinessSegmentsAxis = cmcsa_CableCommunicationsSegmentRevenuePercentageBusinessServicesMember | 8.50%cmcsa_CableSegmentRevenueTypesAsPercentageOfTotalCableRevenue / us-gaap_StatementBusinessSegmentsAxis = cmcsa_CableCommunicationsSegmentRevenuePercentageBusinessServicesMember
Cable Communications Segment Revenue Percentage- Advertising [Member] |  |
Cable segment revenue types as percentage of total cable revenue | 4.40%cmcsa_CableSegmentRevenueTypesAsPercentageOfTotalCableRevenue / us-gaap_StatementBusinessSegmentsAxis = cmcsa_CableCommunicationsSegmentRevenuePercentageAdvertisingMember | 4.70%cmcsa_CableSegmentRevenueTypesAsPercentageOfTotalCableRevenue / us-gaap_StatementBusinessSegmentsAxis = cmcsa_CableCommunicationsSegmentRevenuePercentageAdvertisingMember
Cable Communications Segment Revenue Percentage- Other [Member] |  |
Cable segment revenue types as percentage of total cable revenue | 4.80%cmcsa_CableSegmentRevenueTypesAsPercentageOfTotalCableRevenue / us-gaap_StatementBusinessSegmentsAxis = cmcsa_CableCommunicationsSegmentRevenuePercentageOtherMember | 4.60%cmcsa_CableSegmentRevenueTypesAsPercentageOfTotalCableRevenue / us-gaap_StatementBusinessSegmentsAxis = cmcsa_CableCommunicationsSegmentRevenuePercentageOtherMember
Cable Communications Segment Revenue Percentage- Franchise and other regulatory fees [Member] |  |
Cable segment revenue types as percentage of total cable revenue | 2.80%cmcsa_CableSegmentRevenueTypesAsPercentageOfTotalCableRevenue / us-gaap_StatementBusinessSegmentsAxis = cmcsa_CableCommunicationsSegmentRevenuePercentageFranchiseFeesMember | 2.80%cmcsa_CableSegmentRevenueTypesAsPercentageOfTotalCableRevenue / us-gaap_StatementBusinessSegmentsAxis = cmcsa_CableCommunicationsSegmentRevenuePercentageFranchiseFeesMember

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