v2.4.1.9

Consolidated Statement of Comprehensive Income (USD $) In Millions, unless otherwise specified | 12 Months Ended
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Dec. 31, 2014 | Dec. 31, 2013 | Dec. 31, 2012
Net income | $ 8,592 us-gaap_ProfitLoss | $ 7,135 us-gaap_ProfitLoss | $ 7,865 us-gaap_ProfitLoss
Unrealized gains (losses) on marketable securities, net of deferred taxes | 33 us-gaap_OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax | 185 us-gaap_OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax | 161 us-gaap_OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax
Deferred gains (losses) on cash flow hedges, net of deferred taxes | (5)us-gaap_OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodNetOfTax | 25 us-gaap_OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodNetOfTax | 58 us-gaap_OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodNetOfTax
Amounts Reclassified To Net Income: |  |  |
Realized (gains) losses on marketable securities, net of deferred taxes | (99)us-gaap_OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesNetOfTax | (301)us-gaap_OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesNetOfTax | 0 us-gaap_OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesNetOfTax
Realized (gains) losses on cash flow hedges, net of deferred taxes | 46 us-gaap_OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIOnDerivativesNetOfTax | (3)us-gaap_OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIOnDerivativesNetOfTax | (15)us-gaap_OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIOnDerivativesNetOfTax
Employee benefit obligations, net of deferred taxes | (139)us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax | 181 us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax | (31)us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax
Currency translation adjustments, net of deferred taxes | (38)us-gaap_OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax | (29)us-gaap_OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax | 0 us-gaap_OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax
Comprehensive income | 8,390 us-gaap_ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest | 7,193 us-gaap_ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest | 8,038 us-gaap_ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest
Net (income) loss attributable to noncontrolling interests and redeemable subsidiary preferred stock | (212)cmcsa_NetIncomeLossAttributableToNoncontrollingInterestsAndRedeemableSubsidiaryPreferredStock | (319)cmcsa_NetIncomeLossAttributableToNoncontrollingInterestsAndRedeemableSubsidiaryPreferredStock | (1,662)cmcsa_NetIncomeLossAttributableToNoncontrollingInterestsAndRedeemableSubsidiaryPreferredStock
Other comprehensive (income) loss attributable to noncontrolling interests | 0 us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToNoncontrollingInterest | 9 us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToNoncontrollingInterest | (6)us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToNoncontrollingInterest
Comprehensive income attributable to Parent | 8,178 us-gaap_ComprehensiveIncomeNetOfTax | 6,883 us-gaap_ComprehensiveIncomeNetOfTax | 6,370 us-gaap_ComprehensiveIncomeNetOfTax
NBCUniversal Media, LLC [Member] |  |  |
Net income | 3,297 us-gaap_ProfitLoss / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember | 2,122 us-gaap_ProfitLoss / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember | 3,231 us-gaap_ProfitLoss / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember
Unrealized gains (losses) on marketable securities, net of deferred taxes | 0 us-gaap_OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember | 0 us-gaap_OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember | 0 us-gaap_OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember
Deferred gains (losses) on cash flow hedges, net of deferred taxes | 25 us-gaap_OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodNetOfTax / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember | (5)us-gaap_OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodNetOfTax / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember | 0 us-gaap_OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodNetOfTax / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember
Amounts Reclassified To Net Income: |  |  |
Employee benefit obligations, net of deferred taxes | (106)us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember | 95 us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember | 14 us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember
Currency translation adjustments, net of deferred taxes | (62)us-gaap_OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember | (41)us-gaap_OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember | (1)us-gaap_OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember
Comprehensive income | 3,154 us-gaap_ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember | 2,171 us-gaap_ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember | 3,244 us-gaap_ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember
Net (income) loss attributable to noncontrolling interests | (182)us-gaap_NetIncomeLossAttributableToNoncontrollingInterest / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember | (154)us-gaap_NetIncomeLossAttributableToNoncontrollingInterest / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember | (176)us-gaap_NetIncomeLossAttributableToNoncontrollingInterest / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember
Comprehensive income attributable to Parent | $ 2,972 us-gaap_ComprehensiveIncomeNetOfTax / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember | $ 2,017 us-gaap_ComprehensiveIncomeNetOfTax / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember | $ 3,068 us-gaap_ComprehensiveIncomeNetOfTax / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember

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