v2.4.1.9

Condensed Consolidated Statement of Changes in Equity (USD $) In Millions | Total | NBCUniversal Media, LLC [Member] | Redeemable Noncontrolling Interests And Redeemable Subisdiary Preferred Stock [Member] | Class A Common Stock [Member] | Class A Special Common Stock [Member] | Class B Common Stock [Member] | Additional Paid-In Capital [Member] | Retained Earnings [Member] | Treasury Stock at Cost [Member] | Accumulated Other Comprehensive Income (Loss) [Member] | Accumulated Other Comprehensive Income (Loss) [Member] NBCUniversal Media, LLC [Member] | Noncontrolling Interests [Member] | Noncontrolling Interests [Member] NBCUniversal Media, LLC [Member] | Redeemable Noncontrolling Interest [Member] NBCUniversal Media, LLC [Member] | Member's Capital [Member] NBCUniversal Media, LLC [Member]
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Beginning balance at Dec. 31, 2013 |  | $ 29,327 us-gaap_LimitedLiabilityCompanyLlcMembersEquityIncludingPortionAttributableToNoncontrollingInterest / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember |  |  |  |  |  |  |  |  | $ (16)us-gaap_LimitedLiabilityCompanyLlcMembersEquityIncludingPortionAttributableToNoncontrollingInterest / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementEquityComponentsAxis = us-gaap_AccumulatedOtherComprehensiveIncomeMember |  | $ 287 us-gaap_LimitedLiabilityCompanyLlcMembersEquityIncludingPortionAttributableToNoncontrollingInterest / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementEquityComponentsAxis = us-gaap_NoncontrollingInterestMember | $ 231 us-gaap_LimitedLiabilityCompanyLlcMembersEquityIncludingPortionAttributableToNoncontrollingInterest / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementEquityComponentsAxis = cmcsa_RedeemableNoncontrollingInterestMember | $ 29,056 us-gaap_LimitedLiabilityCompanyLlcMembersEquityIncludingPortionAttributableToNoncontrollingInterest / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementEquityComponentsAxis = cmcsa_MembersCapitalMember
Beginning Balance at Dec. 31, 2013 | 51,058 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest |  | 957 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest / us-gaap_StatementEquityComponentsAxis = cmcsa_RedeemableNoncontrollingInterestsAndRedeemableSubisdiaryPreferredStockMember | 25 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest / us-gaap_StatementEquityComponentsAxis = us-gaap_CommonClassAMember | 5 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest / us-gaap_StatementEquityComponentsAxis = cmcsa_ClassaSpecialCommonStockMember | 0 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest / us-gaap_StatementEquityComponentsAxis = us-gaap_CommonClassBMember | 38,890 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest / us-gaap_StatementEquityComponentsAxis = us-gaap_AdditionalPaidInCapitalMember | 19,235 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest / us-gaap_StatementEquityComponentsAxis = us-gaap_RetainedEarningsMember | (7,517)us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest / us-gaap_StatementEquityComponentsAxis = us-gaap_TreasuryStockMember | 56 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest / us-gaap_StatementEquityComponentsAxis = us-gaap_AccumulatedOtherComprehensiveIncomeMember |  | 364 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest / us-gaap_StatementEquityComponentsAxis = us-gaap_NoncontrollingInterestMember |  |  |
Stock compensation plans | 36 us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation |  |  |  |  |  | 242 us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation / us-gaap_StatementEquityComponentsAxis = us-gaap_AdditionalPaidInCapitalMember | (206)us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation / us-gaap_StatementEquityComponentsAxis = us-gaap_RetainedEarningsMember |  |  |  |  |  |  |
Repurchases and retirements of common stock | (750)us-gaap_StockRepurchasedAndRetiredDuringPeriodValue |  |  |  |  |  | (172)us-gaap_StockRepurchasedAndRetiredDuringPeriodValue / us-gaap_StatementEquityComponentsAxis = us-gaap_AdditionalPaidInCapitalMember | (578)us-gaap_StockRepurchasedAndRetiredDuringPeriodValue / us-gaap_StatementEquityComponentsAxis = us-gaap_RetainedEarningsMember |  |  |  |  |  |  |
Employee stock purchase plans | 26 us-gaap_StockIssuedDuringPeriodValueEmployeeStockPurchasePlan |  |  |  |  |  | 26 us-gaap_StockIssuedDuringPeriodValueEmployeeStockPurchasePlan / us-gaap_StatementEquityComponentsAxis = us-gaap_AdditionalPaidInCapitalMember |  |  |  |  |  |  |  |
Other comprehensive income (loss) | (23)us-gaap_OtherComprehensiveIncomeLossNetOfTax | 3 us-gaap_OtherComprehensiveIncomeLossNetOfTax / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember |  |  |  |  |  |  |  | (23)us-gaap_OtherComprehensiveIncomeLossNetOfTax / us-gaap_StatementEquityComponentsAxis = us-gaap_AccumulatedOtherComprehensiveIncomeMember | 3 us-gaap_OtherComprehensiveIncomeLossNetOfTax / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementEquityComponentsAxis = us-gaap_AccumulatedOtherComprehensiveIncomeMember |  |  |  |
Dividends declared | (585)us-gaap_DividendsCommonStockCash | (195)us-gaap_DividendsCommonStockCash / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember |  |  |  |  |  | (585)us-gaap_DividendsCommonStockCash / us-gaap_StatementEquityComponentsAxis = us-gaap_RetainedEarningsMember |  |  |  |  |  |  | (195)us-gaap_DividendsCommonStockCash / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementEquityComponentsAxis = cmcsa_MembersCapitalMember
Issuance of subsidiary shares to noncontrolling interests |  |  | 82 cmcsa_NoncontrollingInterestIncreaseFromEquityIssuanceOrSaleOfParentEquityInterest / us-gaap_StatementEquityComponentsAxis = cmcsa_RedeemableNoncontrollingInterestsAndRedeemableSubisdiaryPreferredStockMember |  |  |  |  |  |  |  |  |  |  | 82 cmcsa_NoncontrollingInterestIncreaseFromEquityIssuanceOrSaleOfParentEquityInterest / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementEquityComponentsAxis = cmcsa_RedeemableNoncontrollingInterestMember |
Contributions from (distributions to) noncontrolling interests, net | (37)cmcsa_ContributionsFromAndDistributionsToNoncontrollingInterests | (44)cmcsa_ContributionsFromAndDistributionsToNoncontrollingInterests / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember | (5)cmcsa_ContributionsFromAndDistributionsToNoncontrollingInterests / us-gaap_StatementEquityComponentsAxis = cmcsa_RedeemableNoncontrollingInterestsAndRedeemableSubisdiaryPreferredStockMember |  |  |  |  |  |  |  |  | (37)cmcsa_ContributionsFromAndDistributionsToNoncontrollingInterests / us-gaap_StatementEquityComponentsAxis = us-gaap_NoncontrollingInterestMember | (44)cmcsa_ContributionsFromAndDistributionsToNoncontrollingInterests / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementEquityComponentsAxis = us-gaap_NoncontrollingInterestMember | (10)cmcsa_ContributionsFromAndDistributionsToNoncontrollingInterests / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementEquityComponentsAxis = cmcsa_RedeemableNoncontrollingInterestMember |
Other | (7)us-gaap_StockholdersEquityOther |  | (5)us-gaap_StockholdersEquityOther / us-gaap_StatementEquityComponentsAxis = cmcsa_RedeemableNoncontrollingInterestsAndRedeemableSubisdiaryPreferredStockMember |  |  |  | (1)us-gaap_StockholdersEquityOther / us-gaap_StatementEquityComponentsAxis = us-gaap_AdditionalPaidInCapitalMember |  |  |  |  | (6)us-gaap_StockholdersEquityOther / us-gaap_StatementEquityComponentsAxis = us-gaap_NoncontrollingInterestMember | 1 us-gaap_StockholdersEquityOther / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementEquityComponentsAxis = us-gaap_NoncontrollingInterestMember |  | (1)us-gaap_StockholdersEquityOther / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementEquityComponentsAxis = cmcsa_MembersCapitalMember
Net income (loss) | 1,914 cmcsa_EquityProfitLoss | 727 cmcsa_EquityProfitLoss / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember | 24 cmcsa_EquityProfitLoss / us-gaap_StatementEquityComponentsAxis = cmcsa_RedeemableNoncontrollingInterestsAndRedeemableSubisdiaryPreferredStockMember |  |  |  |  | 1,871 cmcsa_EquityProfitLoss / us-gaap_StatementEquityComponentsAxis = us-gaap_RetainedEarningsMember |  |  |  | 43 cmcsa_EquityProfitLoss / us-gaap_StatementEquityComponentsAxis = us-gaap_NoncontrollingInterestMember | 45 cmcsa_EquityProfitLoss / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementEquityComponentsAxis = us-gaap_NoncontrollingInterestMember | 14 cmcsa_EquityProfitLoss / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementEquityComponentsAxis = cmcsa_RedeemableNoncontrollingInterestMember | 682 cmcsa_EquityProfitLoss / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementEquityComponentsAxis = cmcsa_MembersCapitalMember
Ending Balance at Mar. 31, 2014 | 51,632 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest | 29,818 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember | 1,053 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest / us-gaap_StatementEquityComponentsAxis = cmcsa_RedeemableNoncontrollingInterestsAndRedeemableSubisdiaryPreferredStockMember | 25 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest / us-gaap_StatementEquityComponentsAxis = us-gaap_CommonClassAMember | 5 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest / us-gaap_StatementEquityComponentsAxis = cmcsa_ClassaSpecialCommonStockMember | 0 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest / us-gaap_StatementEquityComponentsAxis = us-gaap_CommonClassBMember | 38,985 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest / us-gaap_StatementEquityComponentsAxis = us-gaap_AdditionalPaidInCapitalMember | 19,737 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest / us-gaap_StatementEquityComponentsAxis = us-gaap_RetainedEarningsMember | (7,517)us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest / us-gaap_StatementEquityComponentsAxis = us-gaap_TreasuryStockMember | 33 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest / us-gaap_StatementEquityComponentsAxis = us-gaap_AccumulatedOtherComprehensiveIncomeMember | (13)us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementEquityComponentsAxis = us-gaap_AccumulatedOtherComprehensiveIncomeMember | 364 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest / us-gaap_StatementEquityComponentsAxis = us-gaap_NoncontrollingInterestMember | 289 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementEquityComponentsAxis = us-gaap_NoncontrollingInterestMember | 317 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementEquityComponentsAxis = cmcsa_RedeemableNoncontrollingInterestMember | 29,542 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementEquityComponentsAxis = cmcsa_MembersCapitalMember
Beginning balance at Dec. 31, 2014 |  | 30,637 us-gaap_LimitedLiabilityCompanyLlcMembersEquityIncludingPortionAttributableToNoncontrollingInterest / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember |  |  |  |  |  |  |  |  | (159)us-gaap_LimitedLiabilityCompanyLlcMembersEquityIncludingPortionAttributableToNoncontrollingInterest / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementEquityComponentsAxis = us-gaap_AccumulatedOtherComprehensiveIncomeMember |  | 267 us-gaap_LimitedLiabilityCompanyLlcMembersEquityIncludingPortionAttributableToNoncontrollingInterest / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementEquityComponentsAxis = us-gaap_NoncontrollingInterestMember | 330 us-gaap_LimitedLiabilityCompanyLlcMembersEquityIncludingPortionAttributableToNoncontrollingInterest / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementEquityComponentsAxis = cmcsa_RedeemableNoncontrollingInterestMember | 30,529 us-gaap_LimitedLiabilityCompanyLlcMembersEquityIncludingPortionAttributableToNoncontrollingInterest / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementEquityComponentsAxis = cmcsa_MembersCapitalMember
Beginning Balance at Dec. 31, 2014 | 53,068 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest |  | 1,066 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest / us-gaap_StatementEquityComponentsAxis = cmcsa_RedeemableNoncontrollingInterestsAndRedeemableSubisdiaryPreferredStockMember | 25 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest / us-gaap_StatementEquityComponentsAxis = us-gaap_CommonClassAMember | 5 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest / us-gaap_StatementEquityComponentsAxis = cmcsa_ClassaSpecialCommonStockMember | 0 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest / us-gaap_StatementEquityComponentsAxis = us-gaap_CommonClassBMember | 38,805 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest / us-gaap_StatementEquityComponentsAxis = us-gaap_AdditionalPaidInCapitalMember | 21,539 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest / us-gaap_StatementEquityComponentsAxis = us-gaap_RetainedEarningsMember | (7,517)us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest / us-gaap_StatementEquityComponentsAxis = us-gaap_TreasuryStockMember | (146)us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest / us-gaap_StatementEquityComponentsAxis = us-gaap_AccumulatedOtherComprehensiveIncomeMember |  | 357 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest / us-gaap_StatementEquityComponentsAxis = us-gaap_NoncontrollingInterestMember |  |  |
Stock compensation plans | 43 us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation |  |  |  |  |  | 232 us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation / us-gaap_StatementEquityComponentsAxis = us-gaap_AdditionalPaidInCapitalMember | (189)us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation / us-gaap_StatementEquityComponentsAxis = us-gaap_RetainedEarningsMember |  |  |  |  |  |  |
Repurchases and retirements of common stock | (2,000)us-gaap_StockRepurchasedAndRetiredDuringPeriodValue |  |  |  |  |  | (407)us-gaap_StockRepurchasedAndRetiredDuringPeriodValue / us-gaap_StatementEquityComponentsAxis = us-gaap_AdditionalPaidInCapitalMember | (1,593)us-gaap_StockRepurchasedAndRetiredDuringPeriodValue / us-gaap_StatementEquityComponentsAxis = us-gaap_RetainedEarningsMember |  |  |  |  |  |  |
Employee stock purchase plans | 30 us-gaap_StockIssuedDuringPeriodValueEmployeeStockPurchasePlan |  |  |  |  |  | 30 us-gaap_StockIssuedDuringPeriodValueEmployeeStockPurchasePlan / us-gaap_StatementEquityComponentsAxis = us-gaap_AdditionalPaidInCapitalMember |  |  |  |  |  |  |  |
Other comprehensive income (loss) | (42)us-gaap_OtherComprehensiveIncomeLossNetOfTax | (51)us-gaap_OtherComprehensiveIncomeLossNetOfTax / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember |  |  |  |  |  |  |  | (42)us-gaap_OtherComprehensiveIncomeLossNetOfTax / us-gaap_StatementEquityComponentsAxis = us-gaap_AccumulatedOtherComprehensiveIncomeMember | (51)us-gaap_OtherComprehensiveIncomeLossNetOfTax / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementEquityComponentsAxis = us-gaap_AccumulatedOtherComprehensiveIncomeMember |  |  |  |
Dividends declared | (630)us-gaap_DividendsCommonStockCash | (195)us-gaap_DividendsCommonStockCash / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember |  |  |  |  |  | (630)us-gaap_DividendsCommonStockCash / us-gaap_StatementEquityComponentsAxis = us-gaap_RetainedEarningsMember |  |  |  |  |  |  | (195)us-gaap_DividendsCommonStockCash / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementEquityComponentsAxis = cmcsa_MembersCapitalMember
Contributions from (distributions to) noncontrolling interests, net | (34)cmcsa_ContributionsFromAndDistributionsToNoncontrollingInterests | (41)cmcsa_ContributionsFromAndDistributionsToNoncontrollingInterests / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember |  |  |  |  |  |  |  |  |  | (34)cmcsa_ContributionsFromAndDistributionsToNoncontrollingInterests / us-gaap_StatementEquityComponentsAxis = us-gaap_NoncontrollingInterestMember | (41)cmcsa_ContributionsFromAndDistributionsToNoncontrollingInterests / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementEquityComponentsAxis = us-gaap_NoncontrollingInterestMember | (10)cmcsa_ContributionsFromAndDistributionsToNoncontrollingInterests / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementEquityComponentsAxis = cmcsa_RedeemableNoncontrollingInterestMember |
Other | (39)us-gaap_StockholdersEquityOther | (15)us-gaap_StockholdersEquityOther / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember | 7 us-gaap_StockholdersEquityOther / us-gaap_StatementEquityComponentsAxis = cmcsa_RedeemableNoncontrollingInterestsAndRedeemableSubisdiaryPreferredStockMember |  |  |  |  |  |  |  |  | (39)us-gaap_StockholdersEquityOther / us-gaap_StatementEquityComponentsAxis = us-gaap_NoncontrollingInterestMember | (14)us-gaap_StockholdersEquityOther / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementEquityComponentsAxis = us-gaap_NoncontrollingInterestMember |  | (1)us-gaap_StockholdersEquityOther / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementEquityComponentsAxis = cmcsa_MembersCapitalMember
Net income (loss) | 2,115 cmcsa_EquityProfitLoss | 902 cmcsa_EquityProfitLoss / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember | 26 cmcsa_EquityProfitLoss / us-gaap_StatementEquityComponentsAxis = cmcsa_RedeemableNoncontrollingInterestsAndRedeemableSubisdiaryPreferredStockMember |  |  |  |  | 2,059 cmcsa_EquityProfitLoss / us-gaap_StatementEquityComponentsAxis = us-gaap_RetainedEarningsMember |  |  |  | 56 cmcsa_EquityProfitLoss / us-gaap_StatementEquityComponentsAxis = us-gaap_NoncontrollingInterestMember | 50 cmcsa_EquityProfitLoss / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementEquityComponentsAxis = us-gaap_NoncontrollingInterestMember | 16 cmcsa_EquityProfitLoss / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementEquityComponentsAxis = cmcsa_RedeemableNoncontrollingInterestMember | 852 cmcsa_EquityProfitLoss / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementEquityComponentsAxis = cmcsa_MembersCapitalMember
Ending Balance at Mar. 31, 2015 | 52,511 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest |  | 1,099 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest / us-gaap_StatementEquityComponentsAxis = cmcsa_RedeemableNoncontrollingInterestsAndRedeemableSubisdiaryPreferredStockMember | 25 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest / us-gaap_StatementEquityComponentsAxis = us-gaap_CommonClassAMember | 5 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest / us-gaap_StatementEquityComponentsAxis = cmcsa_ClassaSpecialCommonStockMember | 0 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest / us-gaap_StatementEquityComponentsAxis = us-gaap_CommonClassBMember | 38,660 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest / us-gaap_StatementEquityComponentsAxis = us-gaap_AdditionalPaidInCapitalMember | 21,186 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest / us-gaap_StatementEquityComponentsAxis = us-gaap_RetainedEarningsMember | (7,517)us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest / us-gaap_StatementEquityComponentsAxis = us-gaap_TreasuryStockMember | (188)us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest / us-gaap_StatementEquityComponentsAxis = us-gaap_AccumulatedOtherComprehensiveIncomeMember |  | 340 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest / us-gaap_StatementEquityComponentsAxis = us-gaap_NoncontrollingInterestMember |  |  |
Ending balance at Mar. 31, 2015 |  | $ 31,237 us-gaap_LimitedLiabilityCompanyLlcMembersEquityIncludingPortionAttributableToNoncontrollingInterest / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember |  |  |  |  |  |  |  |  | $ (210)us-gaap_LimitedLiabilityCompanyLlcMembersEquityIncludingPortionAttributableToNoncontrollingInterest / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementEquityComponentsAxis = us-gaap_AccumulatedOtherComprehensiveIncomeMember |  | $ 262 us-gaap_LimitedLiabilityCompanyLlcMembersEquityIncludingPortionAttributableToNoncontrollingInterest / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementEquityComponentsAxis = us-gaap_NoncontrollingInterestMember | $ 336 us-gaap_LimitedLiabilityCompanyLlcMembersEquityIncludingPortionAttributableToNoncontrollingInterest / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementEquityComponentsAxis = cmcsa_RedeemableNoncontrollingInterestMember | $ 31,185 us-gaap_LimitedLiabilityCompanyLlcMembersEquityIncludingPortionAttributableToNoncontrollingInterest / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_StatementEquityComponentsAxis = cmcsa_MembersCapitalMember

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- Definition Amount of stockholders' equity (deficit), net of receivables from officers, directors, owners, and affiliates of the entity, attributable to both the parent and noncontrolling interests. Amount excludes temporary equity. Alternate caption for the concept is permanent equity. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 45 -Paragraph 15 -URI http://asc.fasb.org/extlink&oid=7656940&loc=SL4568447-111683 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 45 -Paragraph 16 -URI http://asc.fasb.org/extlink&oid=7656940&loc=SL4568740-111683 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 55 -Paragraph 4I -URI http://asc.fasb.org/extlink&oid=35736750&loc=SL4590271-111686 + Details
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- Definition Aggregate change in value for stock issued during the period as a result of employee stock purchase plan. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Article 3 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.3-04) -URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 29, 30, 31 -Article 5 + Details
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- Definition Equity impact of the value of stock that has been repurchased and retired during the period. The excess of the purchase price over par value can be charged against retained earnings (once the excess is fully allocated to additional paid in capital). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Article 3 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 29, 30, 31 -Article 5 + Details
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