v2.4.1.9

Investments (Details) (USD $) | Dec. 31, 2014 | Dec. 31, 2013
--- | --- | ---
Fair value method | $ 662,000,000 us-gaap_MarketableSecurities | $ 4,345,000,000 us-gaap_MarketableSecurities
Equity method | 1,019,000,000 us-gaap_EquityMethodInvestments | 989,000,000 us-gaap_EquityMethodInvestments
Cost method | 2,056,000,000 us-gaap_CostMethodInvestments | 2,009,000,000 us-gaap_CostMethodInvestments
Total Investments | 3,737,000,000 us-gaap_Investments | 7,343,000,000 us-gaap_Investments
Less: Current investments | 602,000,000 us-gaap_ShortTermInvestments | 3,573,000,000 us-gaap_ShortTermInvestments
Noncurrent investments | 3,135,000,000 us-gaap_LongTermInvestments | 3,770,000,000 us-gaap_LongTermInvestments
NBCUniversal Media, LLC [Member] |  |
Fair value method | 10,000,000 us-gaap_MarketableSecurities / cmcsa_LegalEntity1Axis = cmcsa_NBCUniversalMediaLLCMember | 11,000,000 us-gaap_MarketableSecurities / cmcsa_LegalEntity1Axis = cmcsa_NBCUniversalMediaLLCMember
Equity method | 840,000,000 us-gaap_EquityMethodInvestments / cmcsa_LegalEntity1Axis = cmcsa_NBCUniversalMediaLLCMember | 852,000,000 us-gaap_EquityMethodInvestments / cmcsa_LegalEntity1Axis = cmcsa_NBCUniversalMediaLLCMember
Cost method | 32,000,000 us-gaap_CostMethodInvestments / cmcsa_LegalEntity1Axis = cmcsa_NBCUniversalMediaLLCMember | 21,000,000 us-gaap_CostMethodInvestments / cmcsa_LegalEntity1Axis = cmcsa_NBCUniversalMediaLLCMember
Total Investments | 882,000,000 us-gaap_Investments / cmcsa_LegalEntity1Axis = cmcsa_NBCUniversalMediaLLCMember | 884,000,000 us-gaap_Investments / cmcsa_LegalEntity1Axis = cmcsa_NBCUniversalMediaLLCMember
Other Equity Method Investments [Member] |  |
Equity method | 517,000,000 us-gaap_EquityMethodInvestments / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = cmcsa_OtherEquityMethodInvestmentsMember | 469,000,000 us-gaap_EquityMethodInvestments / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = cmcsa_OtherEquityMethodInvestmentsMember
Other Equity Method Investments [Member] | NBCUniversal Media, LLC [Member] |  |
Equity method | 338,000,000 us-gaap_EquityMethodInvestments / cmcsa_LegalEntity1Axis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = cmcsa_OtherEquityMethodInvestmentsMember | 332,000,000 us-gaap_EquityMethodInvestments / cmcsa_LegalEntity1Axis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = cmcsa_OtherEquityMethodInvestmentsMember
Air Touch [Member] |  |
Cost method | 1,568,000,000 us-gaap_CostMethodInvestments / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = cmcsa_AirTouchMember | 1,553,000,000 us-gaap_CostMethodInvestments / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = cmcsa_AirTouchMember
Other Investment [Member] |  |
Cost method | 488,000,000 us-gaap_CostMethodInvestments / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = cmcsa_OtherInvestmentMember | 456,000,000 us-gaap_CostMethodInvestments / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = cmcsa_OtherInvestmentMember
The Weather Channel [Member] |  |
Equity method | 335,000,000 us-gaap_EquityMethodInvestments / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = cmcsa_WeatherChannelMember | 333,000,000 us-gaap_EquityMethodInvestments / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = cmcsa_WeatherChannelMember
The Weather Channel [Member] | NBCUniversal Media, LLC [Member] |  |
Equity method | 335,000,000 us-gaap_EquityMethodInvestments / cmcsa_LegalEntity1Axis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = cmcsa_WeatherChannelMember | 333,000,000 us-gaap_EquityMethodInvestments / cmcsa_LegalEntity1Axis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = cmcsa_WeatherChannelMember
Hulu [Member] |  |
Equity method | 167,000,000 us-gaap_EquityMethodInvestments / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = cmcsa_HuluMember | 187,000,000 us-gaap_EquityMethodInvestments / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = cmcsa_HuluMember
Hulu [Member] | NBCUniversal Media, LLC [Member] |  |
Equity method | $ 167,000,000 us-gaap_EquityMethodInvestments / cmcsa_LegalEntity1Axis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = cmcsa_HuluMember | $ 187,000,000 us-gaap_EquityMethodInvestments / cmcsa_LegalEntity1Axis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = cmcsa_HuluMember

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