v2.4.1.9

Long-Term Debt (Details) | Dec. 31, 2014 USD ($) | Dec. 31, 2013 USD ($) | Dec. 31, 2014 NBCUniversal Media, LLC [Member] USD ($) | Dec. 31, 2013 NBCUniversal Media, LLC [Member] USD ($) | Dec. 31, 2014 Revolving bank credit facility [Member] | Dec. 31, 2014 Commercial Paper Program | Dec. 31, 2014 Senior notes with maturities of 5 years or less [Member] USD ($) | Dec. 31, 2013 Senior notes with maturities of 5 years or less [Member] USD ($) | Dec. 31, 2014 Senior notes with maturities of 5 years or less [Member] NBCUniversal Media, LLC [Member] USD ($) | Dec. 31, 2013 Senior notes with maturities of 5 years or less [Member] NBCUniversal Media, LLC [Member] USD ($) | Dec. 31, 2014 Senior notes with maturities between 5 and 10 years [Member] USD ($) | Dec. 31, 2013 Senior notes with maturities between 5 and 10 years [Member] USD ($) | Dec. 31, 2014 Senior notes with maturities between 5 and 10 years [Member] NBCUniversal Media, LLC [Member] USD ($) | Dec. 31, 2013 Senior notes with maturities between 5 and 10 years [Member] NBCUniversal Media, LLC [Member] USD ($) | Dec. 31, 2014 Senior notes with maturities greater than 10 years [Member] USD ($) | Dec. 31, 2013 Senior notes with maturities greater than 10 years [Member] USD ($) | Dec. 31, 2014 Senior notes with maturities greater than 10 years [Member] NBCUniversal Media, LLC [Member] USD ($) | Dec. 31, 2013 Senior notes with maturities greater than 10 years [Member] NBCUniversal Media, LLC [Member] USD ($) | Dec. 31, 2014 Other Including Capital Lease Obligations [Member] USD ($) | Dec. 31, 2013 Other Including Capital Lease Obligations [Member] USD ($) | Dec. 31, 2014 Other Including Capital Lease Obligations [Member] NBCUniversal Media, LLC [Member] USD ($) | Dec. 31, 2013 Other Including Capital Lease Obligations [Member] NBCUniversal Media, LLC [Member] USD ($) | Dec. 31, 2014 Notes 5.50% Due 2029 [Member] USD ($) | Dec. 31, 2014 Notes 5.50% Due 2029 [Member] GBP (£) | Dec. 31, 2013 Notes 5.50% Due 2029 [Member] USD ($) | Dec. 31, 2013 Notes 5.50% Due 2029 [Member] GBP (£)
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Commercial paper | $ 845,000,000 us-gaap_CommercialPaper | $ 1,350,000,000 us-gaap_CommercialPaper |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Revolving credit facilities | 0 us-gaap_LineOfCreditFacilityAmountOutstanding | 1,250,000,000 us-gaap_LineOfCreditFacilityAmountOutstanding |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Senior notes |  |  |  |  |  |  | 15,334,000,000 us-gaap_SeniorNotes / us-gaap_DebtInstrumentAxis = cmcsa_SeniorNotesWithMaturitiesOf5YearsOrLessMember | 15,080,000,000 us-gaap_SeniorNotes / us-gaap_DebtInstrumentAxis = cmcsa_SeniorNotesWithMaturitiesOf5YearsOrLessMember | 2,005,000,000 us-gaap_SeniorNotes / us-gaap_DebtInstrumentAxis = cmcsa_SeniorNotesWithMaturitiesOf5YearsOrLessMember / cmcsa_LegalEntity1Axis = cmcsa_NBCUniversalMediaLLCMember | 2,917,000,000 us-gaap_SeniorNotes / us-gaap_DebtInstrumentAxis = cmcsa_SeniorNotesWithMaturitiesOf5YearsOrLessMember / cmcsa_LegalEntity1Axis = cmcsa_NBCUniversalMediaLLCMember | 10,527,000,000 us-gaap_SeniorNotes / us-gaap_DebtInstrumentAxis = cmcsa_SeniorNotesWithMaturitiesBetween5And10YearsMember | 11,533,000,000 us-gaap_SeniorNotes / us-gaap_DebtInstrumentAxis = cmcsa_SeniorNotesWithMaturitiesBetween5And10YearsMember | 4,996,000,000 us-gaap_SeniorNotes / us-gaap_DebtInstrumentAxis = cmcsa_SeniorNotesWithMaturitiesBetween5And10YearsMember / cmcsa_LegalEntity1Axis = cmcsa_NBCUniversalMediaLLCMember | 4,996,000,000 us-gaap_SeniorNotes / us-gaap_DebtInstrumentAxis = cmcsa_SeniorNotesWithMaturitiesBetween5And10YearsMember / cmcsa_LegalEntity1Axis = cmcsa_NBCUniversalMediaLLCMember | 20,937,000,000 us-gaap_SeniorNotes / us-gaap_DebtInstrumentAxis = cmcsa_SeniorNotesWithMaturitiesGreaterThan10YearsMember | 18,010,000,000 us-gaap_SeniorNotes / us-gaap_DebtInstrumentAxis = cmcsa_SeniorNotesWithMaturitiesGreaterThan10YearsMember | 3,204,000,000 us-gaap_SeniorNotes / us-gaap_DebtInstrumentAxis = cmcsa_SeniorNotesWithMaturitiesGreaterThan10YearsMember / cmcsa_LegalEntity1Axis = cmcsa_NBCUniversalMediaLLCMember | 3,205,000,000 us-gaap_SeniorNotes / us-gaap_DebtInstrumentAxis = cmcsa_SeniorNotesWithMaturitiesGreaterThan10YearsMember / cmcsa_LegalEntity1Axis = cmcsa_NBCUniversalMediaLLCMember |  |  |  |  | 974,000,000 us-gaap_SeniorNotes / us-gaap_DebtInstrumentAxis = cmcsa_Notes550Due2029Member | 625,000,000 us-gaap_SeniorNotes / us-gaap_DebtInstrumentAxis = cmcsa_Notes550Due2029Member | 1,000,000,000 us-gaap_SeniorNotes / us-gaap_DebtInstrumentAxis = cmcsa_Notes550Due2029Member | 625,000,000 us-gaap_SeniorNotes / us-gaap_DebtInstrumentAxis = cmcsa_Notes550Due2029Member
Other, including capital lease obligations |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 591,000,000 us-gaap_OtherBorrowings / us-gaap_DebtInstrumentAxis = cmcsa_OtherIncludingCapitalLeaseObligationsMember | 624,000,000 us-gaap_OtherBorrowings / us-gaap_DebtInstrumentAxis = cmcsa_OtherIncludingCapitalLeaseObligationsMember | 44,000,000 us-gaap_OtherBorrowings / us-gaap_DebtInstrumentAxis = cmcsa_OtherIncludingCapitalLeaseObligationsMember / cmcsa_LegalEntity1Axis = cmcsa_NBCUniversalMediaLLCMember | 47,000,000 us-gaap_OtherBorrowings / us-gaap_DebtInstrumentAxis = cmcsa_OtherIncludingCapitalLeaseObligationsMember / cmcsa_LegalEntity1Axis = cmcsa_NBCUniversalMediaLLCMember |  |  |  |
Total debt | 48,234,000,000 us-gaap_DebtAndCapitalLeaseObligations | 47,847,000,000 us-gaap_DebtAndCapitalLeaseObligations | 10,249,000,000 us-gaap_DebtAndCapitalLeaseObligations / cmcsa_LegalEntity1Axis = cmcsa_NBCUniversalMediaLLCMember | 11,165,000,000 us-gaap_DebtAndCapitalLeaseObligations / cmcsa_LegalEntity1Axis = cmcsa_NBCUniversalMediaLLCMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Less: current portion | 4,217,000,000 us-gaap_DebtCurrent | 3,280,000,000 us-gaap_DebtCurrent | 1,023,000,000 us-gaap_DebtCurrent / cmcsa_LegalEntity1Axis = cmcsa_NBCUniversalMediaLLCMember | 906,000,000 us-gaap_DebtCurrent / cmcsa_LegalEntity1Axis = cmcsa_NBCUniversalMediaLLCMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Long-term debt, less current portion | $ 44,017,000,000 us-gaap_LongTermDebtAndCapitalLeaseObligations | $ 44,567,000,000 us-gaap_LongTermDebtAndCapitalLeaseObligations | $ 9,226,000,000 us-gaap_LongTermDebtAndCapitalLeaseObligations / cmcsa_LegalEntity1Axis = cmcsa_NBCUniversalMediaLLCMember | $ 10,259,000,000 us-gaap_LongTermDebtAndCapitalLeaseObligations / cmcsa_LegalEntity1Axis = cmcsa_NBCUniversalMediaLLCMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Weighted average interest rate | 4.95%us-gaap_DebtWeightedAverageInterestRate |  | 4.46%us-gaap_DebtWeightedAverageInterestRate / cmcsa_LegalEntity1Axis = cmcsa_NBCUniversalMediaLLCMember |  | 0.00%us-gaap_DebtWeightedAverageInterestRate / us-gaap_DebtInstrumentAxis = cmcsa_RevolvingBankCreditFacilityMember | 0.373%us-gaap_DebtWeightedAverageInterestRate / us-gaap_DebtInstrumentAxis = us-gaap_CommercialPaperMember | 4.642%us-gaap_DebtWeightedAverageInterestRate / us-gaap_DebtInstrumentAxis = cmcsa_SeniorNotesWithMaturitiesOf5YearsOrLessMember |  | 3.254%us-gaap_DebtWeightedAverageInterestRate / us-gaap_DebtInstrumentAxis = cmcsa_SeniorNotesWithMaturitiesOf5YearsOrLessMember / cmcsa_LegalEntity1Axis = cmcsa_NBCUniversalMediaLLCMember |  | 4.822%us-gaap_DebtWeightedAverageInterestRate / us-gaap_DebtInstrumentAxis = cmcsa_SeniorNotesWithMaturitiesBetween5And10YearsMember |  | 4.389%us-gaap_DebtWeightedAverageInterestRate / us-gaap_DebtInstrumentAxis = cmcsa_SeniorNotesWithMaturitiesBetween5And10YearsMember / cmcsa_LegalEntity1Axis = cmcsa_NBCUniversalMediaLLCMember |  | 5.737%us-gaap_DebtWeightedAverageInterestRate / us-gaap_DebtInstrumentAxis = cmcsa_SeniorNotesWithMaturitiesGreaterThan10YearsMember |  | 5.614%us-gaap_DebtWeightedAverageInterestRate / us-gaap_DebtInstrumentAxis = cmcsa_SeniorNotesWithMaturitiesGreaterThan10YearsMember / cmcsa_LegalEntity1Axis = cmcsa_NBCUniversalMediaLLCMember |  |  |  |  |  |  |  |  |

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