v2.4.1.9

Supplemental Financial Information (Net Cash Provided by Operating Activities)(Details) (USD $) | 3 Months Ended
--- | ---
Mar. 31, 2015 | Mar. 31, 2014
Net income | $ 2,141,000,000 us-gaap_ProfitLoss | $ 1,938,000,000 us-gaap_ProfitLoss
Adjustments to reconcile net income to net cash provided by operating activities: |  |
Depreciation and amortization | 2,066,000,000 us-gaap_DepreciationAndAmortization | 1,970,000,000 us-gaap_DepreciationAndAmortization
Share-based compensation | 135,000,000 us-gaap_ShareBasedCompensation | 119,000,000 us-gaap_ShareBasedCompensation
Noncash interest expense (income), net | 51,000,000 cmcsa_NoncashInterestExpenseIncomeNet | 42,000,000 cmcsa_NoncashInterestExpenseIncomeNet
Equity in net (income) losses of investees, net | (33,000,000)us-gaap_IncomeLossFromEquityMethodInvestments | (32,000,000)us-gaap_IncomeLossFromEquityMethodInvestments
Cash received from investees | 22,000,000 us-gaap_EquityMethodInvestmentDividendsOrDistributions | 18,000,000 us-gaap_EquityMethodInvestmentDividendsOrDistributions
Net (gain) loss on investment activity and other | (121,000,000)cmcsa_GainLossOnInvestmentsAndNoncashOtherIncomeExpenseNet | (59,000,000)cmcsa_GainLossOnInvestmentsAndNoncashOtherIncomeExpenseNet
Deferred income taxes | (119,000,000)us-gaap_DeferredIncomeTaxExpenseBenefit | (226,000,000)us-gaap_DeferredIncomeTaxExpenseBenefit
Changes in operating assets and liabilities, net of effects of acquisitions and divestitures: |  |
Current and noncurrent receivables, net | 119,000,000 cmcsa_ChangeInCurrentAndNoncurrentReceivablesNet | 195,000,000 cmcsa_ChangeInCurrentAndNoncurrentReceivablesNet
Film and television costs, net | (38,000,000)cmcsa_FilmAndTelevisionCostsNet | 154,000,000 cmcsa_FilmAndTelevisionCostsNet
Accounts payable and accrued expenses related to trade creditors (cash flow) | 372,000,000 us-gaap_IncreaseDecreaseInAccountsPayableAndAccruedLiabilities | 82,000,000 us-gaap_IncreaseDecreaseInAccountsPayableAndAccruedLiabilities
Other operating assets and liabilities | 650,000,000 us-gaap_IncreaseDecreaseInOtherOperatingCapitalNet | 285,000,000 us-gaap_IncreaseDecreaseInOtherOperatingCapitalNet
Net cash provided by operating activities | 5,245,000,000 us-gaap_NetCashProvidedByUsedInOperatingActivities | 4,486,000,000 us-gaap_NetCashProvidedByUsedInOperatingActivities
NBCUniversal Media, LLC [Member] |  |
Net income | 918,000,000 us-gaap_ProfitLoss / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember | 741,000,000 us-gaap_ProfitLoss / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember
Adjustments to reconcile net income to net cash provided by operating activities: |  |
Depreciation and amortization | 364,000,000 us-gaap_DepreciationAndAmortization / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember | 365,000,000 us-gaap_DepreciationAndAmortization / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember
Equity in net (income) losses of investees, net | (20,000,000)us-gaap_IncomeLossFromEquityMethodInvestments / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember | (18,000,000)us-gaap_IncomeLossFromEquityMethodInvestments / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember
Cash received from investees | 12,000,000 us-gaap_EquityMethodInvestmentDividendsOrDistributions / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember | 12,000,000 us-gaap_EquityMethodInvestmentDividendsOrDistributions / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember
Net (gain) loss on investment activity and other | 46,000,000 cmcsa_GainLossOnInvestmentsAndNoncashOtherIncomeExpenseNet / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember | 21,000,000 cmcsa_GainLossOnInvestmentsAndNoncashOtherIncomeExpenseNet / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember
Deferred income taxes | 3,000,000 us-gaap_DeferredIncomeTaxExpenseBenefit / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember | 16,000,000 us-gaap_DeferredIncomeTaxExpenseBenefit / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember
Changes in operating assets and liabilities, net of effects of acquisitions and divestitures: |  |
Current and noncurrent receivables, net | (106,000,000)cmcsa_ChangeInCurrentAndNoncurrentReceivablesNet / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember | 55,000,000 cmcsa_ChangeInCurrentAndNoncurrentReceivablesNet / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember
Film and television costs, net | (36,000,000)cmcsa_FilmAndTelevisionCostsNet / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember | 148,000,000 cmcsa_FilmAndTelevisionCostsNet / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember
Accounts payable and accrued expenses related to trade creditors (cash flow) | 16,000,000 us-gaap_IncreaseDecreaseInAccountsPayableAndAccruedLiabilities / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember | (117,000,000)us-gaap_IncreaseDecreaseInAccountsPayableAndAccruedLiabilities / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember
Other operating assets and liabilities | 5,000,000 us-gaap_IncreaseDecreaseInOtherOperatingCapitalNet / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember | (467,000,000)us-gaap_IncreaseDecreaseInOtherOperatingCapitalNet / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember
Net cash provided by operating activities | $ 1,202,000,000 us-gaap_NetCashProvidedByUsedInOperatingActivities / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember | $ 756,000,000 us-gaap_NetCashProvidedByUsedInOperatingActivities / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember

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