v2.4.1.9

Condensed Consolidating Financial Information (Condensed Consolidating Balance Sheet) (Details) (USD $) | Dec. 31, 2014 | Dec. 31, 2013 | Dec. 31, 2012 | Dec. 31, 2011
--- | --- | --- | --- | ---
Cash and cash equivalents | $ 3,910,000,000 us-gaap_CashAndCashEquivalentsAtCarryingValue | $ 1,718,000,000 us-gaap_CashAndCashEquivalentsAtCarryingValue | $ 10,951,000,000 us-gaap_CashAndCashEquivalentsAtCarryingValue | $ 1,620,000,000 us-gaap_CashAndCashEquivalentsAtCarryingValue
Investments [Current] | 602,000,000 us-gaap_ShortTermInvestments | 3,573,000,000 us-gaap_ShortTermInvestments |  |
Receivables, net | 6,321,000,000 us-gaap_AccountsReceivableNetCurrent | 6,376,000,000 us-gaap_AccountsReceivableNetCurrent |  |
Programming rights | 839,000,000 cmcsa_ProgrammingRightsCurrent | 928,000,000 cmcsa_ProgrammingRightsCurrent |  |
Other current assets | 1,859,000,000 us-gaap_OtherAssetsCurrent | 1,480,000,000 us-gaap_OtherAssetsCurrent |  |
Total current assets | 13,531,000,000 us-gaap_AssetsCurrent | 14,075,000,000 us-gaap_AssetsCurrent |  |
Film and television costs | 5,727,000,000 cmcsa_FilmAndTelevisionCosts | 4,994,000,000 cmcsa_FilmAndTelevisionCosts |  |
Investments | 3,135,000,000 us-gaap_LongTermInvestments | 3,770,000,000 us-gaap_LongTermInvestments |  |
Property and equipment, net | 30,953,000,000 us-gaap_PropertyPlantAndEquipmentNet | 29,840,000,000 us-gaap_PropertyPlantAndEquipmentNet |  |
Franchise rights | 59,364,000,000 us-gaap_IndefiniteLivedFranchiseRights | 59,364,000,000 us-gaap_IndefiniteLivedFranchiseRights |  |
Goodwill | 27,316,000,000 us-gaap_Goodwill | 27,098,000,000 us-gaap_Goodwill | 26,985,000,000 us-gaap_Goodwill |
Other intangible assets, net | 16,980,000,000 us-gaap_OtherIntangibleAssetsNet | 17,329,000,000 us-gaap_OtherIntangibleAssetsNet |  |
Other noncurrent assets, net | 2,333,000,000 us-gaap_OtherAssetsNoncurrent | 2,343,000,000 us-gaap_OtherAssetsNoncurrent |  |
Total assets | 159,339,000,000 us-gaap_Assets | 158,813,000,000 us-gaap_Assets |  |
Accounts payable and accrued expenses related to trade creditors | 5,638,000,000 us-gaap_AccountsPayableCurrent | 5,528,000,000 us-gaap_AccountsPayableCurrent |  |
Accrued participations and residuals | 1,347,000,000 cmcsa_AccruedParticipationsAndResidualsCurrent | 1,239,000,000 cmcsa_AccruedParticipationsAndResidualsCurrent |  |
Accrued expenses and other current liabilities [condensed] | 6,208,000,000 cmcsa_AccruedExpensesAndOtherCurrentLiabilitiesIncludingDeferredRevenue | 8,865,000,000 cmcsa_AccruedExpensesAndOtherCurrentLiabilitiesIncludingDeferredRevenue |  |
Current portion of long-term debt | 4,217,000,000 us-gaap_DebtCurrent | 3,280,000,000 us-gaap_DebtCurrent |  |
Total current liabilities | 17,410,000,000 us-gaap_LiabilitiesCurrent | 18,912,000,000 us-gaap_LiabilitiesCurrent |  |
Long-term debt, less current portion | 44,017,000,000 us-gaap_LongTermDebtAndCapitalLeaseObligations | 44,567,000,000 us-gaap_LongTermDebtAndCapitalLeaseObligations |  |
Deferred income taxes | 32,959,000,000 us-gaap_DeferredTaxLiabilitiesNoncurrent | 31,935,000,000 us-gaap_DeferredTaxLiabilitiesNoncurrent |  |
Other noncurrent liabilities | 10,819,000,000 us-gaap_OtherLiabilitiesNoncurrent | 11,384,000,000 us-gaap_OtherLiabilitiesNoncurrent |  |
Redeemable noncontrolling interests and redeemable subsidiary preferred stock | 1,066,000,000 cmcsa_RedeemableNoncontrollingInterestsAndRedeemableSubsidiaryPreferredStock | 957,000,000 cmcsa_RedeemableNoncontrollingInterestsAndRedeemableSubsidiaryPreferredStock |  |
Common stock | 30,000,000 us-gaap_CommonStockValue | 30,000,000 us-gaap_CommonStockValue |  |
Other shareholders' equity | 52,681,000,000 cmcsa_OtherStockholdersEquity | 50,664,000,000 cmcsa_OtherStockholdersEquity |  |
Total Comcast Corporation shareholders' equity | 52,711,000,000 us-gaap_StockholdersEquity | 50,694,000,000 us-gaap_StockholdersEquity |  |
Noncontrolling interests | 357,000,000 us-gaap_MinorityInterest | 364,000,000 us-gaap_MinorityInterest |  |
Total equity | 53,068,000,000 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest | 51,058,000,000 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest | 49,796,000,000 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest | 47,655,000,000 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest
Total liabilities and equity | 159,339,000,000 us-gaap_LiabilitiesAndStockholdersEquity | 158,813,000,000 us-gaap_LiabilitiesAndStockholdersEquity |  |
Elimination and Consolidation Adjustments [Member] |  |  |  |
Cash and cash equivalents | 0 us-gaap_CashAndCashEquivalentsAtCarryingValue / us-gaap_ConsolidationItemsAxis = cmcsa_EliminationAndConsolidationAdjustmentsMember | 0 us-gaap_CashAndCashEquivalentsAtCarryingValue / us-gaap_ConsolidationItemsAxis = cmcsa_EliminationAndConsolidationAdjustmentsMember | 0 us-gaap_CashAndCashEquivalentsAtCarryingValue / us-gaap_ConsolidationItemsAxis = cmcsa_EliminationAndConsolidationAdjustmentsMember | 0 us-gaap_CashAndCashEquivalentsAtCarryingValue / us-gaap_ConsolidationItemsAxis = cmcsa_EliminationAndConsolidationAdjustmentsMember
Investments [Current] | 0 us-gaap_ShortTermInvestments / us-gaap_ConsolidationItemsAxis = cmcsa_EliminationAndConsolidationAdjustmentsMember | 0 us-gaap_ShortTermInvestments / us-gaap_ConsolidationItemsAxis = cmcsa_EliminationAndConsolidationAdjustmentsMember |  |
Receivables, net | 0 us-gaap_AccountsReceivableNetCurrent / us-gaap_ConsolidationItemsAxis = cmcsa_EliminationAndConsolidationAdjustmentsMember | 0 us-gaap_AccountsReceivableNetCurrent / us-gaap_ConsolidationItemsAxis = cmcsa_EliminationAndConsolidationAdjustmentsMember |  |
Programming rights | 0 cmcsa_ProgrammingRightsCurrent / us-gaap_ConsolidationItemsAxis = cmcsa_EliminationAndConsolidationAdjustmentsMember | 0 cmcsa_ProgrammingRightsCurrent / us-gaap_ConsolidationItemsAxis = cmcsa_EliminationAndConsolidationAdjustmentsMember |  |
Other current assets | 0 us-gaap_OtherAssetsCurrent / us-gaap_ConsolidationItemsAxis = cmcsa_EliminationAndConsolidationAdjustmentsMember | 0 us-gaap_OtherAssetsCurrent / us-gaap_ConsolidationItemsAxis = cmcsa_EliminationAndConsolidationAdjustmentsMember |  |
Total current assets | 0 us-gaap_AssetsCurrent / us-gaap_ConsolidationItemsAxis = cmcsa_EliminationAndConsolidationAdjustmentsMember | 0 us-gaap_AssetsCurrent / us-gaap_ConsolidationItemsAxis = cmcsa_EliminationAndConsolidationAdjustmentsMember |  |
Film and television costs | 0 cmcsa_FilmAndTelevisionCosts / us-gaap_ConsolidationItemsAxis = cmcsa_EliminationAndConsolidationAdjustmentsMember | 0 cmcsa_FilmAndTelevisionCosts / us-gaap_ConsolidationItemsAxis = cmcsa_EliminationAndConsolidationAdjustmentsMember |  |
Investments | 0 us-gaap_LongTermInvestments / us-gaap_ConsolidationItemsAxis = cmcsa_EliminationAndConsolidationAdjustmentsMember | 0 us-gaap_LongTermInvestments / us-gaap_ConsolidationItemsAxis = cmcsa_EliminationAndConsolidationAdjustmentsMember |  |
Investments in and amounts due from subsidiaries eliminated upon consolidation | (495,953,000,000)cmcsa_InvestmentsInAndAmountsDueFromSubsidiariesEliminatedUponConsolidation / us-gaap_ConsolidationItemsAxis = cmcsa_EliminationAndConsolidationAdjustmentsMember | (460,590,000,000)cmcsa_InvestmentsInAndAmountsDueFromSubsidiariesEliminatedUponConsolidation / us-gaap_ConsolidationItemsAxis = cmcsa_EliminationAndConsolidationAdjustmentsMember |  |
Property and equipment, net | 0 us-gaap_PropertyPlantAndEquipmentNet / us-gaap_ConsolidationItemsAxis = cmcsa_EliminationAndConsolidationAdjustmentsMember | 0 us-gaap_PropertyPlantAndEquipmentNet / us-gaap_ConsolidationItemsAxis = cmcsa_EliminationAndConsolidationAdjustmentsMember |  |
Franchise rights | 0 us-gaap_IndefiniteLivedFranchiseRights / us-gaap_ConsolidationItemsAxis = cmcsa_EliminationAndConsolidationAdjustmentsMember | 0 us-gaap_IndefiniteLivedFranchiseRights / us-gaap_ConsolidationItemsAxis = cmcsa_EliminationAndConsolidationAdjustmentsMember |  |
Goodwill | 0 us-gaap_Goodwill / us-gaap_ConsolidationItemsAxis = cmcsa_EliminationAndConsolidationAdjustmentsMember | 0 us-gaap_Goodwill / us-gaap_ConsolidationItemsAxis = cmcsa_EliminationAndConsolidationAdjustmentsMember |  |
Other intangible assets, net | 0 us-gaap_OtherIntangibleAssetsNet / us-gaap_ConsolidationItemsAxis = cmcsa_EliminationAndConsolidationAdjustmentsMember | 0 us-gaap_OtherIntangibleAssetsNet / us-gaap_ConsolidationItemsAxis = cmcsa_EliminationAndConsolidationAdjustmentsMember |  |
Other noncurrent assets, net | (1,080,000,000)us-gaap_OtherAssetsNoncurrent / us-gaap_ConsolidationItemsAxis = cmcsa_EliminationAndConsolidationAdjustmentsMember | (882,000,000)us-gaap_OtherAssetsNoncurrent / us-gaap_ConsolidationItemsAxis = cmcsa_EliminationAndConsolidationAdjustmentsMember |  |
Total assets | (497,033,000,000)us-gaap_Assets / us-gaap_ConsolidationItemsAxis = cmcsa_EliminationAndConsolidationAdjustmentsMember | (461,472,000,000)us-gaap_Assets / us-gaap_ConsolidationItemsAxis = cmcsa_EliminationAndConsolidationAdjustmentsMember |  |
Accounts payable and accrued expenses related to trade creditors | 0 us-gaap_AccountsPayableCurrent / us-gaap_ConsolidationItemsAxis = cmcsa_EliminationAndConsolidationAdjustmentsMember | 0 us-gaap_AccountsPayableCurrent / us-gaap_ConsolidationItemsAxis = cmcsa_EliminationAndConsolidationAdjustmentsMember |  |
Accrued participations and residuals | 0 cmcsa_AccruedParticipationsAndResidualsCurrent / us-gaap_ConsolidationItemsAxis = cmcsa_EliminationAndConsolidationAdjustmentsMember | 0 cmcsa_AccruedParticipationsAndResidualsCurrent / us-gaap_ConsolidationItemsAxis = cmcsa_EliminationAndConsolidationAdjustmentsMember |  |
Accrued expenses and other current liabilities [condensed] | 0 cmcsa_AccruedExpensesAndOtherCurrentLiabilitiesIncludingDeferredRevenue / us-gaap_ConsolidationItemsAxis = cmcsa_EliminationAndConsolidationAdjustmentsMember | 0 cmcsa_AccruedExpensesAndOtherCurrentLiabilitiesIncludingDeferredRevenue / us-gaap_ConsolidationItemsAxis = cmcsa_EliminationAndConsolidationAdjustmentsMember |  |
Current portion of long-term debt | 0 us-gaap_DebtCurrent / us-gaap_ConsolidationItemsAxis = cmcsa_EliminationAndConsolidationAdjustmentsMember | 0 us-gaap_DebtCurrent / us-gaap_ConsolidationItemsAxis = cmcsa_EliminationAndConsolidationAdjustmentsMember |  |
Total current liabilities | 0 us-gaap_LiabilitiesCurrent / us-gaap_ConsolidationItemsAxis = cmcsa_EliminationAndConsolidationAdjustmentsMember | 0 us-gaap_LiabilitiesCurrent / us-gaap_ConsolidationItemsAxis = cmcsa_EliminationAndConsolidationAdjustmentsMember |  |
Long-term debt, less current portion | 0 us-gaap_LongTermDebtAndCapitalLeaseObligations / us-gaap_ConsolidationItemsAxis = cmcsa_EliminationAndConsolidationAdjustmentsMember | 0 us-gaap_LongTermDebtAndCapitalLeaseObligations / us-gaap_ConsolidationItemsAxis = cmcsa_EliminationAndConsolidationAdjustmentsMember |  |
Deferred income taxes | (936,000,000)us-gaap_DeferredTaxLiabilitiesNoncurrent / us-gaap_ConsolidationItemsAxis = cmcsa_EliminationAndConsolidationAdjustmentsMember | (741,000,000)us-gaap_DeferredTaxLiabilitiesNoncurrent / us-gaap_ConsolidationItemsAxis = cmcsa_EliminationAndConsolidationAdjustmentsMember |  |
Other noncurrent liabilities | (144,000,000)us-gaap_OtherLiabilitiesNoncurrent / us-gaap_ConsolidationItemsAxis = cmcsa_EliminationAndConsolidationAdjustmentsMember | (141,000,000)us-gaap_OtherLiabilitiesNoncurrent / us-gaap_ConsolidationItemsAxis = cmcsa_EliminationAndConsolidationAdjustmentsMember |  |
Redeemable noncontrolling interests and redeemable subsidiary preferred stock | 0 cmcsa_RedeemableNoncontrollingInterestsAndRedeemableSubsidiaryPreferredStock / us-gaap_ConsolidationItemsAxis = cmcsa_EliminationAndConsolidationAdjustmentsMember | 0 cmcsa_RedeemableNoncontrollingInterestsAndRedeemableSubsidiaryPreferredStock / us-gaap_ConsolidationItemsAxis = cmcsa_EliminationAndConsolidationAdjustmentsMember |  |
Common stock | 0 us-gaap_CommonStockValue / us-gaap_ConsolidationItemsAxis = cmcsa_EliminationAndConsolidationAdjustmentsMember | 0 us-gaap_CommonStockValue / us-gaap_ConsolidationItemsAxis = cmcsa_EliminationAndConsolidationAdjustmentsMember |  |
Other shareholders' equity | (495,953,000,000)cmcsa_OtherStockholdersEquity / us-gaap_ConsolidationItemsAxis = cmcsa_EliminationAndConsolidationAdjustmentsMember | (460,590,000,000)cmcsa_OtherStockholdersEquity / us-gaap_ConsolidationItemsAxis = cmcsa_EliminationAndConsolidationAdjustmentsMember |  |
Total Comcast Corporation shareholders' equity | (495,953,000,000)us-gaap_StockholdersEquity / us-gaap_ConsolidationItemsAxis = cmcsa_EliminationAndConsolidationAdjustmentsMember | (460,590,000,000)us-gaap_StockholdersEquity / us-gaap_ConsolidationItemsAxis = cmcsa_EliminationAndConsolidationAdjustmentsMember |  |
Noncontrolling interests | 0 us-gaap_MinorityInterest / us-gaap_ConsolidationItemsAxis = cmcsa_EliminationAndConsolidationAdjustmentsMember | 0 us-gaap_MinorityInterest / us-gaap_ConsolidationItemsAxis = cmcsa_EliminationAndConsolidationAdjustmentsMember |  |
Total equity | (495,953,000,000)us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest / us-gaap_ConsolidationItemsAxis = cmcsa_EliminationAndConsolidationAdjustmentsMember | (460,590,000,000)us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest / us-gaap_ConsolidationItemsAxis = cmcsa_EliminationAndConsolidationAdjustmentsMember |  |
Total liabilities and equity | (497,033,000,000)us-gaap_LiabilitiesAndStockholdersEquity / us-gaap_ConsolidationItemsAxis = cmcsa_EliminationAndConsolidationAdjustmentsMember | (461,472,000,000)us-gaap_LiabilitiesAndStockholdersEquity / us-gaap_ConsolidationItemsAxis = cmcsa_EliminationAndConsolidationAdjustmentsMember |  |
Comcast Parent [Member] |  |  |  |
Cash and cash equivalents | 0 us-gaap_CashAndCashEquivalentsAtCarryingValue / dei_LegalEntityAxis = us-gaap_ParentCompanyMember | 0 us-gaap_CashAndCashEquivalentsAtCarryingValue / dei_LegalEntityAxis = us-gaap_ParentCompanyMember | 0 us-gaap_CashAndCashEquivalentsAtCarryingValue / dei_LegalEntityAxis = us-gaap_ParentCompanyMember | 0 us-gaap_CashAndCashEquivalentsAtCarryingValue / dei_LegalEntityAxis = us-gaap_ParentCompanyMember
Investments [Current] | 0 us-gaap_ShortTermInvestments / dei_LegalEntityAxis = us-gaap_ParentCompanyMember | 0 us-gaap_ShortTermInvestments / dei_LegalEntityAxis = us-gaap_ParentCompanyMember |  |
Receivables, net | 0 us-gaap_AccountsReceivableNetCurrent / dei_LegalEntityAxis = us-gaap_ParentCompanyMember | 0 us-gaap_AccountsReceivableNetCurrent / dei_LegalEntityAxis = us-gaap_ParentCompanyMember |  |
Programming rights | 0 cmcsa_ProgrammingRightsCurrent / dei_LegalEntityAxis = us-gaap_ParentCompanyMember | 0 cmcsa_ProgrammingRightsCurrent / dei_LegalEntityAxis = us-gaap_ParentCompanyMember |  |
Other current assets | 267,000,000 us-gaap_OtherAssetsCurrent / dei_LegalEntityAxis = us-gaap_ParentCompanyMember | 237,000,000 us-gaap_OtherAssetsCurrent / dei_LegalEntityAxis = us-gaap_ParentCompanyMember |  |
Total current assets | 267,000,000 us-gaap_AssetsCurrent / dei_LegalEntityAxis = us-gaap_ParentCompanyMember | 237,000,000 us-gaap_AssetsCurrent / dei_LegalEntityAxis = us-gaap_ParentCompanyMember |  |
Film and television costs | 0 cmcsa_FilmAndTelevisionCosts / dei_LegalEntityAxis = us-gaap_ParentCompanyMember | 0 cmcsa_FilmAndTelevisionCosts / dei_LegalEntityAxis = us-gaap_ParentCompanyMember |  |
Investments | 36,000,000 us-gaap_LongTermInvestments / dei_LegalEntityAxis = us-gaap_ParentCompanyMember | 11,000,000 us-gaap_LongTermInvestments / dei_LegalEntityAxis = us-gaap_ParentCompanyMember |  |
Investments in and amounts due from subsidiaries eliminated upon consolidation | 84,142,000,000 cmcsa_InvestmentsInAndAmountsDueFromSubsidiariesEliminatedUponConsolidation / dei_LegalEntityAxis = us-gaap_ParentCompanyMember | 79,956,000,000 cmcsa_InvestmentsInAndAmountsDueFromSubsidiariesEliminatedUponConsolidation / dei_LegalEntityAxis = us-gaap_ParentCompanyMember |  |
Property and equipment, net | 199,000,000 us-gaap_PropertyPlantAndEquipmentNet / dei_LegalEntityAxis = us-gaap_ParentCompanyMember | 220,000,000 us-gaap_PropertyPlantAndEquipmentNet / dei_LegalEntityAxis = us-gaap_ParentCompanyMember |  |
Franchise rights | 0 us-gaap_IndefiniteLivedFranchiseRights / dei_LegalEntityAxis = us-gaap_ParentCompanyMember | 0 us-gaap_IndefiniteLivedFranchiseRights / dei_LegalEntityAxis = us-gaap_ParentCompanyMember |  |
Goodwill | 0 us-gaap_Goodwill / dei_LegalEntityAxis = us-gaap_ParentCompanyMember | 0 us-gaap_Goodwill / dei_LegalEntityAxis = us-gaap_ParentCompanyMember |  |
Other intangible assets, net | 11,000,000 us-gaap_OtherIntangibleAssetsNet / dei_LegalEntityAxis = us-gaap_ParentCompanyMember | 11,000,000 us-gaap_OtherIntangibleAssetsNet / dei_LegalEntityAxis = us-gaap_ParentCompanyMember |  |
Other noncurrent assets, net | 1,224,000,000 us-gaap_OtherAssetsNoncurrent / dei_LegalEntityAxis = us-gaap_ParentCompanyMember | 1,078,000,000 us-gaap_OtherAssetsNoncurrent / dei_LegalEntityAxis = us-gaap_ParentCompanyMember |  |
Total assets | 85,879,000,000 us-gaap_Assets / dei_LegalEntityAxis = us-gaap_ParentCompanyMember | 81,513,000,000 us-gaap_Assets / dei_LegalEntityAxis = us-gaap_ParentCompanyMember |  |
Accounts payable and accrued expenses related to trade creditors | 19,000,000 us-gaap_AccountsPayableCurrent / dei_LegalEntityAxis = us-gaap_ParentCompanyMember | 8,000,000 us-gaap_AccountsPayableCurrent / dei_LegalEntityAxis = us-gaap_ParentCompanyMember |  |
Accrued participations and residuals | 0 cmcsa_AccruedParticipationsAndResidualsCurrent / dei_LegalEntityAxis = us-gaap_ParentCompanyMember | 0 cmcsa_AccruedParticipationsAndResidualsCurrent / dei_LegalEntityAxis = us-gaap_ParentCompanyMember |  |
Accrued expenses and other current liabilities [condensed] | 1,547,000,000 cmcsa_AccruedExpensesAndOtherCurrentLiabilitiesIncludingDeferredRevenue / dei_LegalEntityAxis = us-gaap_ParentCompanyMember | 1,371,000,000 cmcsa_AccruedExpensesAndOtherCurrentLiabilitiesIncludingDeferredRevenue / dei_LegalEntityAxis = us-gaap_ParentCompanyMember |  |
Current portion of long-term debt | 1,650,000,000 us-gaap_DebtCurrent / dei_LegalEntityAxis = us-gaap_ParentCompanyMember | 2,351,000,000 us-gaap_DebtCurrent / dei_LegalEntityAxis = us-gaap_ParentCompanyMember |  |
Total current liabilities | 3,216,000,000 us-gaap_LiabilitiesCurrent / dei_LegalEntityAxis = us-gaap_ParentCompanyMember | 3,730,000,000 us-gaap_LiabilitiesCurrent / dei_LegalEntityAxis = us-gaap_ParentCompanyMember |  |
Long-term debt, less current portion | 27,616,000,000 us-gaap_LongTermDebtAndCapitalLeaseObligations / dei_LegalEntityAxis = us-gaap_ParentCompanyMember | 25,170,000,000 us-gaap_LongTermDebtAndCapitalLeaseObligations / dei_LegalEntityAxis = us-gaap_ParentCompanyMember |  |
Deferred income taxes | 0 us-gaap_DeferredTaxLiabilitiesNoncurrent / dei_LegalEntityAxis = us-gaap_ParentCompanyMember | 0 us-gaap_DeferredTaxLiabilitiesNoncurrent / dei_LegalEntityAxis = us-gaap_ParentCompanyMember |  |
Other noncurrent liabilities | 2,336,000,000 us-gaap_OtherLiabilitiesNoncurrent / dei_LegalEntityAxis = us-gaap_ParentCompanyMember | 1,919,000,000 us-gaap_OtherLiabilitiesNoncurrent / dei_LegalEntityAxis = us-gaap_ParentCompanyMember |  |
Redeemable noncontrolling interests and redeemable subsidiary preferred stock | 0 cmcsa_RedeemableNoncontrollingInterestsAndRedeemableSubsidiaryPreferredStock / dei_LegalEntityAxis = us-gaap_ParentCompanyMember | 0 cmcsa_RedeemableNoncontrollingInterestsAndRedeemableSubsidiaryPreferredStock / dei_LegalEntityAxis = us-gaap_ParentCompanyMember |  |
Common stock | 30,000,000 us-gaap_CommonStockValue / dei_LegalEntityAxis = us-gaap_ParentCompanyMember | 30,000,000 us-gaap_CommonStockValue / dei_LegalEntityAxis = us-gaap_ParentCompanyMember |  |
Other shareholders' equity | 52,681,000,000 cmcsa_OtherStockholdersEquity / dei_LegalEntityAxis = us-gaap_ParentCompanyMember | 50,664,000,000 cmcsa_OtherStockholdersEquity / dei_LegalEntityAxis = us-gaap_ParentCompanyMember |  |
Total Comcast Corporation shareholders' equity | 52,711,000,000 us-gaap_StockholdersEquity / dei_LegalEntityAxis = us-gaap_ParentCompanyMember | 50,694,000,000 us-gaap_StockholdersEquity / dei_LegalEntityAxis = us-gaap_ParentCompanyMember |  |
Noncontrolling interests | 0 us-gaap_MinorityInterest / dei_LegalEntityAxis = us-gaap_ParentCompanyMember | 0 us-gaap_MinorityInterest / dei_LegalEntityAxis = us-gaap_ParentCompanyMember |  |
Total equity | 52,711,000,000 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest / dei_LegalEntityAxis = us-gaap_ParentCompanyMember | 50,694,000,000 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest / dei_LegalEntityAxis = us-gaap_ParentCompanyMember |  |
Total liabilities and equity | 85,879,000,000 us-gaap_LiabilitiesAndStockholdersEquity / dei_LegalEntityAxis = us-gaap_ParentCompanyMember | 81,513,000,000 us-gaap_LiabilitiesAndStockholdersEquity / dei_LegalEntityAxis = us-gaap_ParentCompanyMember |  |
Comcast Holdings [Member] |  |  |  |
Cash and cash equivalents | 0 us-gaap_CashAndCashEquivalentsAtCarryingValue / dei_LegalEntityAxis = cmcsa_ComcastHoldingsMember | 0 us-gaap_CashAndCashEquivalentsAtCarryingValue / dei_LegalEntityAxis = cmcsa_ComcastHoldingsMember | 0 us-gaap_CashAndCashEquivalentsAtCarryingValue / dei_LegalEntityAxis = cmcsa_ComcastHoldingsMember | 0 us-gaap_CashAndCashEquivalentsAtCarryingValue / dei_LegalEntityAxis = cmcsa_ComcastHoldingsMember
Investments [Current] | 0 us-gaap_ShortTermInvestments / dei_LegalEntityAxis = cmcsa_ComcastHoldingsMember | 0 us-gaap_ShortTermInvestments / dei_LegalEntityAxis = cmcsa_ComcastHoldingsMember |  |
Receivables, net | 0 us-gaap_AccountsReceivableNetCurrent / dei_LegalEntityAxis = cmcsa_ComcastHoldingsMember | 0 us-gaap_AccountsReceivableNetCurrent / dei_LegalEntityAxis = cmcsa_ComcastHoldingsMember |  |
Programming rights | 0 cmcsa_ProgrammingRightsCurrent / dei_LegalEntityAxis = cmcsa_ComcastHoldingsMember | 0 cmcsa_ProgrammingRightsCurrent / dei_LegalEntityAxis = cmcsa_ComcastHoldingsMember |  |
Other current assets | 0 us-gaap_OtherAssetsCurrent / dei_LegalEntityAxis = cmcsa_ComcastHoldingsMember | 0 us-gaap_OtherAssetsCurrent / dei_LegalEntityAxis = cmcsa_ComcastHoldingsMember |  |
Total current assets | 0 us-gaap_AssetsCurrent / dei_LegalEntityAxis = cmcsa_ComcastHoldingsMember | 0 us-gaap_AssetsCurrent / dei_LegalEntityAxis = cmcsa_ComcastHoldingsMember |  |
Film and television costs | 0 cmcsa_FilmAndTelevisionCosts / dei_LegalEntityAxis = cmcsa_ComcastHoldingsMember | 0 cmcsa_FilmAndTelevisionCosts / dei_LegalEntityAxis = cmcsa_ComcastHoldingsMember |  |
Investments | 0 us-gaap_LongTermInvestments / dei_LegalEntityAxis = cmcsa_ComcastHoldingsMember | 0 us-gaap_LongTermInvestments / dei_LegalEntityAxis = cmcsa_ComcastHoldingsMember |  |
Investments in and amounts due from subsidiaries eliminated upon consolidation | 103,420,000,000 cmcsa_InvestmentsInAndAmountsDueFromSubsidiariesEliminatedUponConsolidation / dei_LegalEntityAxis = cmcsa_ComcastHoldingsMember | 97,429,000,000 cmcsa_InvestmentsInAndAmountsDueFromSubsidiariesEliminatedUponConsolidation / dei_LegalEntityAxis = cmcsa_ComcastHoldingsMember |  |
Property and equipment, net | 0 us-gaap_PropertyPlantAndEquipmentNet / dei_LegalEntityAxis = cmcsa_ComcastHoldingsMember | 0 us-gaap_PropertyPlantAndEquipmentNet / dei_LegalEntityAxis = cmcsa_ComcastHoldingsMember |  |
Franchise rights | 0 us-gaap_IndefiniteLivedFranchiseRights / dei_LegalEntityAxis = cmcsa_ComcastHoldingsMember | 0 us-gaap_IndefiniteLivedFranchiseRights / dei_LegalEntityAxis = cmcsa_ComcastHoldingsMember |  |
Goodwill | 0 us-gaap_Goodwill / dei_LegalEntityAxis = cmcsa_ComcastHoldingsMember | 0 us-gaap_Goodwill / dei_LegalEntityAxis = cmcsa_ComcastHoldingsMember |  |
Other intangible assets, net | 0 us-gaap_OtherIntangibleAssetsNet / dei_LegalEntityAxis = cmcsa_ComcastHoldingsMember | 0 us-gaap_OtherIntangibleAssetsNet / dei_LegalEntityAxis = cmcsa_ComcastHoldingsMember |  |
Other noncurrent assets, net | 148,000,000 us-gaap_OtherAssetsNoncurrent / dei_LegalEntityAxis = cmcsa_ComcastHoldingsMember | 145,000,000 us-gaap_OtherAssetsNoncurrent / dei_LegalEntityAxis = cmcsa_ComcastHoldingsMember |  |
Total assets | 103,568,000,000 us-gaap_Assets / dei_LegalEntityAxis = cmcsa_ComcastHoldingsMember | 97,574,000,000 us-gaap_Assets / dei_LegalEntityAxis = cmcsa_ComcastHoldingsMember |  |
Accounts payable and accrued expenses related to trade creditors | 0 us-gaap_AccountsPayableCurrent / dei_LegalEntityAxis = cmcsa_ComcastHoldingsMember | 0 us-gaap_AccountsPayableCurrent / dei_LegalEntityAxis = cmcsa_ComcastHoldingsMember |  |
Accrued participations and residuals | 0 cmcsa_AccruedParticipationsAndResidualsCurrent / dei_LegalEntityAxis = cmcsa_ComcastHoldingsMember | 0 cmcsa_AccruedParticipationsAndResidualsCurrent / dei_LegalEntityAxis = cmcsa_ComcastHoldingsMember |  |
Accrued expenses and other current liabilities [condensed] | 283,000,000 cmcsa_AccruedExpensesAndOtherCurrentLiabilitiesIncludingDeferredRevenue / dei_LegalEntityAxis = cmcsa_ComcastHoldingsMember | 266,000,000 cmcsa_AccruedExpensesAndOtherCurrentLiabilitiesIncludingDeferredRevenue / dei_LegalEntityAxis = cmcsa_ComcastHoldingsMember |  |
Current portion of long-term debt | 0 us-gaap_DebtCurrent / dei_LegalEntityAxis = cmcsa_ComcastHoldingsMember | 0 us-gaap_DebtCurrent / dei_LegalEntityAxis = cmcsa_ComcastHoldingsMember |  |
Total current liabilities | 283,000,000 us-gaap_LiabilitiesCurrent / dei_LegalEntityAxis = cmcsa_ComcastHoldingsMember | 266,000,000 us-gaap_LiabilitiesCurrent / dei_LegalEntityAxis = cmcsa_ComcastHoldingsMember |  |
Long-term debt, less current portion | 126,000,000 us-gaap_LongTermDebtAndCapitalLeaseObligations / dei_LegalEntityAxis = cmcsa_ComcastHoldingsMember | 132,000,000 us-gaap_LongTermDebtAndCapitalLeaseObligations / dei_LegalEntityAxis = cmcsa_ComcastHoldingsMember |  |
Deferred income taxes | 701,000,000 us-gaap_DeferredTaxLiabilitiesNoncurrent / dei_LegalEntityAxis = cmcsa_ComcastHoldingsMember | 777,000,000 us-gaap_DeferredTaxLiabilitiesNoncurrent / dei_LegalEntityAxis = cmcsa_ComcastHoldingsMember |  |
Other noncurrent liabilities | 0 us-gaap_OtherLiabilitiesNoncurrent / dei_LegalEntityAxis = cmcsa_ComcastHoldingsMember | 0 us-gaap_OtherLiabilitiesNoncurrent / dei_LegalEntityAxis = cmcsa_ComcastHoldingsMember |  |
Redeemable noncontrolling interests and redeemable subsidiary preferred stock | 0 cmcsa_RedeemableNoncontrollingInterestsAndRedeemableSubsidiaryPreferredStock / dei_LegalEntityAxis = cmcsa_ComcastHoldingsMember | 0 cmcsa_RedeemableNoncontrollingInterestsAndRedeemableSubsidiaryPreferredStock / dei_LegalEntityAxis = cmcsa_ComcastHoldingsMember |  |
Common stock | 0 us-gaap_CommonStockValue / dei_LegalEntityAxis = cmcsa_ComcastHoldingsMember | 0 us-gaap_CommonStockValue / dei_LegalEntityAxis = cmcsa_ComcastHoldingsMember |  |
Other shareholders' equity | 102,458,000,000 cmcsa_OtherStockholdersEquity / dei_LegalEntityAxis = cmcsa_ComcastHoldingsMember | 96,399,000,000 cmcsa_OtherStockholdersEquity / dei_LegalEntityAxis = cmcsa_ComcastHoldingsMember |  |
Total Comcast Corporation shareholders' equity | 102,458,000,000 us-gaap_StockholdersEquity / dei_LegalEntityAxis = cmcsa_ComcastHoldingsMember | 96,399,000,000 us-gaap_StockholdersEquity / dei_LegalEntityAxis = cmcsa_ComcastHoldingsMember |  |
Noncontrolling interests | 0 us-gaap_MinorityInterest / dei_LegalEntityAxis = cmcsa_ComcastHoldingsMember | 0 us-gaap_MinorityInterest / dei_LegalEntityAxis = cmcsa_ComcastHoldingsMember |  |
Total equity | 102,458,000,000 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest / dei_LegalEntityAxis = cmcsa_ComcastHoldingsMember | 96,399,000,000 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest / dei_LegalEntityAxis = cmcsa_ComcastHoldingsMember |  |
Total liabilities and equity | 103,568,000,000 us-gaap_LiabilitiesAndStockholdersEquity / dei_LegalEntityAxis = cmcsa_ComcastHoldingsMember | 97,574,000,000 us-gaap_LiabilitiesAndStockholdersEquity / dei_LegalEntityAxis = cmcsa_ComcastHoldingsMember |  |
CCCL Parent [Member] |  |  |  |
Cash and cash equivalents | 0 us-gaap_CashAndCashEquivalentsAtCarryingValue / dei_LegalEntityAxis = cmcsa_CcclParentMember | 0 us-gaap_CashAndCashEquivalentsAtCarryingValue / dei_LegalEntityAxis = cmcsa_CcclParentMember | 0 us-gaap_CashAndCashEquivalentsAtCarryingValue / dei_LegalEntityAxis = cmcsa_CcclParentMember | 0 us-gaap_CashAndCashEquivalentsAtCarryingValue / dei_LegalEntityAxis = cmcsa_CcclParentMember
Investments [Current] | 0 us-gaap_ShortTermInvestments / dei_LegalEntityAxis = cmcsa_CcclParentMember | 0 us-gaap_ShortTermInvestments / dei_LegalEntityAxis = cmcsa_CcclParentMember |  |
Receivables, net | 0 us-gaap_AccountsReceivableNetCurrent / dei_LegalEntityAxis = cmcsa_CcclParentMember | 0 us-gaap_AccountsReceivableNetCurrent / dei_LegalEntityAxis = cmcsa_CcclParentMember |  |
Programming rights | 0 cmcsa_ProgrammingRightsCurrent / dei_LegalEntityAxis = cmcsa_CcclParentMember | 0 cmcsa_ProgrammingRightsCurrent / dei_LegalEntityAxis = cmcsa_CcclParentMember |  |
Other current assets | 0 us-gaap_OtherAssetsCurrent / dei_LegalEntityAxis = cmcsa_CcclParentMember | 0 us-gaap_OtherAssetsCurrent / dei_LegalEntityAxis = cmcsa_CcclParentMember |  |
Total current assets | 0 us-gaap_AssetsCurrent / dei_LegalEntityAxis = cmcsa_CcclParentMember | 0 us-gaap_AssetsCurrent / dei_LegalEntityAxis = cmcsa_CcclParentMember |  |
Film and television costs | 0 cmcsa_FilmAndTelevisionCosts / dei_LegalEntityAxis = cmcsa_CcclParentMember | 0 cmcsa_FilmAndTelevisionCosts / dei_LegalEntityAxis = cmcsa_CcclParentMember |  |
Investments | 0 us-gaap_LongTermInvestments / dei_LegalEntityAxis = cmcsa_CcclParentMember | 0 us-gaap_LongTermInvestments / dei_LegalEntityAxis = cmcsa_CcclParentMember |  |
Investments in and amounts due from subsidiaries eliminated upon consolidation | 110,323,000,000 cmcsa_InvestmentsInAndAmountsDueFromSubsidiariesEliminatedUponConsolidation / dei_LegalEntityAxis = cmcsa_CcclParentMember | 102,673,000,000 cmcsa_InvestmentsInAndAmountsDueFromSubsidiariesEliminatedUponConsolidation / dei_LegalEntityAxis = cmcsa_CcclParentMember |  |
Property and equipment, net | 0 us-gaap_PropertyPlantAndEquipmentNet / dei_LegalEntityAxis = cmcsa_CcclParentMember | 0 us-gaap_PropertyPlantAndEquipmentNet / dei_LegalEntityAxis = cmcsa_CcclParentMember |  |
Franchise rights | 0 us-gaap_IndefiniteLivedFranchiseRights / dei_LegalEntityAxis = cmcsa_CcclParentMember | 0 us-gaap_IndefiniteLivedFranchiseRights / dei_LegalEntityAxis = cmcsa_CcclParentMember |  |
Goodwill | 0 us-gaap_Goodwill / dei_LegalEntityAxis = cmcsa_CcclParentMember | 0 us-gaap_Goodwill / dei_LegalEntityAxis = cmcsa_CcclParentMember |  |
Other intangible assets, net | 0 us-gaap_OtherIntangibleAssetsNet / dei_LegalEntityAxis = cmcsa_CcclParentMember | 0 us-gaap_OtherIntangibleAssetsNet / dei_LegalEntityAxis = cmcsa_CcclParentMember |  |
Other noncurrent assets, net | 0 us-gaap_OtherAssetsNoncurrent / dei_LegalEntityAxis = cmcsa_CcclParentMember | 0 us-gaap_OtherAssetsNoncurrent / dei_LegalEntityAxis = cmcsa_CcclParentMember |  |
Total assets | 110,323,000,000 us-gaap_Assets / dei_LegalEntityAxis = cmcsa_CcclParentMember | 102,673,000,000 us-gaap_Assets / dei_LegalEntityAxis = cmcsa_CcclParentMember |  |
Accounts payable and accrued expenses related to trade creditors | 0 us-gaap_AccountsPayableCurrent / dei_LegalEntityAxis = cmcsa_CcclParentMember | 0 us-gaap_AccountsPayableCurrent / dei_LegalEntityAxis = cmcsa_CcclParentMember |  |
Accrued participations and residuals | 0 cmcsa_AccruedParticipationsAndResidualsCurrent / dei_LegalEntityAxis = cmcsa_CcclParentMember | 0 cmcsa_AccruedParticipationsAndResidualsCurrent / dei_LegalEntityAxis = cmcsa_CcclParentMember |  |
Accrued expenses and other current liabilities [condensed] | 233,000,000 cmcsa_AccruedExpensesAndOtherCurrentLiabilitiesIncludingDeferredRevenue / dei_LegalEntityAxis = cmcsa_CcclParentMember | 180,000,000 cmcsa_AccruedExpensesAndOtherCurrentLiabilitiesIncludingDeferredRevenue / dei_LegalEntityAxis = cmcsa_CcclParentMember |  |
Current portion of long-term debt | 0 us-gaap_DebtCurrent / dei_LegalEntityAxis = cmcsa_CcclParentMember | 0 us-gaap_DebtCurrent / dei_LegalEntityAxis = cmcsa_CcclParentMember |  |
Total current liabilities | 233,000,000 us-gaap_LiabilitiesCurrent / dei_LegalEntityAxis = cmcsa_CcclParentMember | 180,000,000 us-gaap_LiabilitiesCurrent / dei_LegalEntityAxis = cmcsa_CcclParentMember |  |
Long-term debt, less current portion | 1,827,000,000 us-gaap_LongTermDebtAndCapitalLeaseObligations / dei_LegalEntityAxis = cmcsa_CcclParentMember | 1,827,000,000 us-gaap_LongTermDebtAndCapitalLeaseObligations / dei_LegalEntityAxis = cmcsa_CcclParentMember |  |
Deferred income taxes | 0 us-gaap_DeferredTaxLiabilitiesNoncurrent / dei_LegalEntityAxis = cmcsa_CcclParentMember | 0 us-gaap_DeferredTaxLiabilitiesNoncurrent / dei_LegalEntityAxis = cmcsa_CcclParentMember |  |
Other noncurrent liabilities | 0 us-gaap_OtherLiabilitiesNoncurrent / dei_LegalEntityAxis = cmcsa_CcclParentMember | 0 us-gaap_OtherLiabilitiesNoncurrent / dei_LegalEntityAxis = cmcsa_CcclParentMember |  |
Redeemable noncontrolling interests and redeemable subsidiary preferred stock | 0 cmcsa_RedeemableNoncontrollingInterestsAndRedeemableSubsidiaryPreferredStock / dei_LegalEntityAxis = cmcsa_CcclParentMember | 0 cmcsa_RedeemableNoncontrollingInterestsAndRedeemableSubsidiaryPreferredStock / dei_LegalEntityAxis = cmcsa_CcclParentMember |  |
Common stock | 0 us-gaap_CommonStockValue / dei_LegalEntityAxis = cmcsa_CcclParentMember | 0 us-gaap_CommonStockValue / dei_LegalEntityAxis = cmcsa_CcclParentMember |  |
Other shareholders' equity | 108,263,000,000 cmcsa_OtherStockholdersEquity / dei_LegalEntityAxis = cmcsa_CcclParentMember | 100,666,000,000 cmcsa_OtherStockholdersEquity / dei_LegalEntityAxis = cmcsa_CcclParentMember |  |
Total Comcast Corporation shareholders' equity | 108,263,000,000 us-gaap_StockholdersEquity / dei_LegalEntityAxis = cmcsa_CcclParentMember | 100,666,000,000 us-gaap_StockholdersEquity / dei_LegalEntityAxis = cmcsa_CcclParentMember |  |
Noncontrolling interests | 0 us-gaap_MinorityInterest / dei_LegalEntityAxis = cmcsa_CcclParentMember | 0 us-gaap_MinorityInterest / dei_LegalEntityAxis = cmcsa_CcclParentMember |  |
Total equity | 108,263,000,000 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest / dei_LegalEntityAxis = cmcsa_CcclParentMember | 100,666,000,000 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest / dei_LegalEntityAxis = cmcsa_CcclParentMember |  |
Total liabilities and equity | 110,323,000,000 us-gaap_LiabilitiesAndStockholdersEquity / dei_LegalEntityAxis = cmcsa_CcclParentMember | 102,673,000,000 us-gaap_LiabilitiesAndStockholdersEquity / dei_LegalEntityAxis = cmcsa_CcclParentMember |  |
Combined CCHMO Parents [Member] |  |  |  |
Cash and cash equivalents | 0 us-gaap_CashAndCashEquivalentsAtCarryingValue / dei_LegalEntityAxis = cmcsa_CombinedCchmoParentsMember | 0 us-gaap_CashAndCashEquivalentsAtCarryingValue / dei_LegalEntityAxis = cmcsa_CombinedCchmoParentsMember | 0 us-gaap_CashAndCashEquivalentsAtCarryingValue / dei_LegalEntityAxis = cmcsa_CombinedCchmoParentsMember | 0 us-gaap_CashAndCashEquivalentsAtCarryingValue / dei_LegalEntityAxis = cmcsa_CombinedCchmoParentsMember
Investments [Current] | 0 us-gaap_ShortTermInvestments / dei_LegalEntityAxis = cmcsa_CombinedCchmoParentsMember | 0 us-gaap_ShortTermInvestments / dei_LegalEntityAxis = cmcsa_CombinedCchmoParentsMember |  |
Receivables, net | 0 us-gaap_AccountsReceivableNetCurrent / dei_LegalEntityAxis = cmcsa_CombinedCchmoParentsMember | 0 us-gaap_AccountsReceivableNetCurrent / dei_LegalEntityAxis = cmcsa_CombinedCchmoParentsMember |  |
Programming rights | 0 cmcsa_ProgrammingRightsCurrent / dei_LegalEntityAxis = cmcsa_CombinedCchmoParentsMember | 0 cmcsa_ProgrammingRightsCurrent / dei_LegalEntityAxis = cmcsa_CombinedCchmoParentsMember |  |
Other current assets | 0 us-gaap_OtherAssetsCurrent / dei_LegalEntityAxis = cmcsa_CombinedCchmoParentsMember | 0 us-gaap_OtherAssetsCurrent / dei_LegalEntityAxis = cmcsa_CombinedCchmoParentsMember |  |
Total current assets | 0 us-gaap_AssetsCurrent / dei_LegalEntityAxis = cmcsa_CombinedCchmoParentsMember | 0 us-gaap_AssetsCurrent / dei_LegalEntityAxis = cmcsa_CombinedCchmoParentsMember |  |
Film and television costs | 0 cmcsa_FilmAndTelevisionCosts / dei_LegalEntityAxis = cmcsa_CombinedCchmoParentsMember | 0 cmcsa_FilmAndTelevisionCosts / dei_LegalEntityAxis = cmcsa_CombinedCchmoParentsMember |  |
Investments | 0 us-gaap_LongTermInvestments / dei_LegalEntityAxis = cmcsa_CombinedCchmoParentsMember | 0 us-gaap_LongTermInvestments / dei_LegalEntityAxis = cmcsa_CombinedCchmoParentsMember |  |
Investments in and amounts due from subsidiaries eliminated upon consolidation | 58,677,000,000 cmcsa_InvestmentsInAndAmountsDueFromSubsidiariesEliminatedUponConsolidation / dei_LegalEntityAxis = cmcsa_CombinedCchmoParentsMember | 54,724,000,000 cmcsa_InvestmentsInAndAmountsDueFromSubsidiariesEliminatedUponConsolidation / dei_LegalEntityAxis = cmcsa_CombinedCchmoParentsMember |  |
Property and equipment, net | 0 us-gaap_PropertyPlantAndEquipmentNet / dei_LegalEntityAxis = cmcsa_CombinedCchmoParentsMember | 0 us-gaap_PropertyPlantAndEquipmentNet / dei_LegalEntityAxis = cmcsa_CombinedCchmoParentsMember |  |
Franchise rights | 0 us-gaap_IndefiniteLivedFranchiseRights / dei_LegalEntityAxis = cmcsa_CombinedCchmoParentsMember | 0 us-gaap_IndefiniteLivedFranchiseRights / dei_LegalEntityAxis = cmcsa_CombinedCchmoParentsMember |  |
Goodwill | 0 us-gaap_Goodwill / dei_LegalEntityAxis = cmcsa_CombinedCchmoParentsMember | 0 us-gaap_Goodwill / dei_LegalEntityAxis = cmcsa_CombinedCchmoParentsMember |  |
Other intangible assets, net | 0 us-gaap_OtherIntangibleAssetsNet / dei_LegalEntityAxis = cmcsa_CombinedCchmoParentsMember | 0 us-gaap_OtherIntangibleAssetsNet / dei_LegalEntityAxis = cmcsa_CombinedCchmoParentsMember |  |
Other noncurrent assets, net | 0 us-gaap_OtherAssetsNoncurrent / dei_LegalEntityAxis = cmcsa_CombinedCchmoParentsMember | 0 us-gaap_OtherAssetsNoncurrent / dei_LegalEntityAxis = cmcsa_CombinedCchmoParentsMember |  |
Total assets | 58,677,000,000 us-gaap_Assets / dei_LegalEntityAxis = cmcsa_CombinedCchmoParentsMember | 54,724,000,000 us-gaap_Assets / dei_LegalEntityAxis = cmcsa_CombinedCchmoParentsMember |  |
Accounts payable and accrued expenses related to trade creditors | 1,000,000 us-gaap_AccountsPayableCurrent / dei_LegalEntityAxis = cmcsa_CombinedCchmoParentsMember | 0 us-gaap_AccountsPayableCurrent / dei_LegalEntityAxis = cmcsa_CombinedCchmoParentsMember |  |
Accrued participations and residuals | 0 cmcsa_AccruedParticipationsAndResidualsCurrent / dei_LegalEntityAxis = cmcsa_CombinedCchmoParentsMember | 0 cmcsa_AccruedParticipationsAndResidualsCurrent / dei_LegalEntityAxis = cmcsa_CombinedCchmoParentsMember |  |
Accrued expenses and other current liabilities [condensed] | 47,000,000 cmcsa_AccruedExpensesAndOtherCurrentLiabilitiesIncludingDeferredRevenue / dei_LegalEntityAxis = cmcsa_CombinedCchmoParentsMember | 47,000,000 cmcsa_AccruedExpensesAndOtherCurrentLiabilitiesIncludingDeferredRevenue / dei_LegalEntityAxis = cmcsa_CombinedCchmoParentsMember |  |
Current portion of long-term debt | 677,000,000 us-gaap_DebtCurrent / dei_LegalEntityAxis = cmcsa_CombinedCchmoParentsMember | 0 us-gaap_DebtCurrent / dei_LegalEntityAxis = cmcsa_CombinedCchmoParentsMember |  |
Total current liabilities | 725,000,000 us-gaap_LiabilitiesCurrent / dei_LegalEntityAxis = cmcsa_CombinedCchmoParentsMember | 47,000,000 us-gaap_LiabilitiesCurrent / dei_LegalEntityAxis = cmcsa_CombinedCchmoParentsMember |  |
Long-term debt, less current portion | 822,000,000 us-gaap_LongTermDebtAndCapitalLeaseObligations / dei_LegalEntityAxis = cmcsa_CombinedCchmoParentsMember | 1,505,000,000 us-gaap_LongTermDebtAndCapitalLeaseObligations / dei_LegalEntityAxis = cmcsa_CombinedCchmoParentsMember |  |
Deferred income taxes | 0 us-gaap_DeferredTaxLiabilitiesNoncurrent / dei_LegalEntityAxis = cmcsa_CombinedCchmoParentsMember | 0 us-gaap_DeferredTaxLiabilitiesNoncurrent / dei_LegalEntityAxis = cmcsa_CombinedCchmoParentsMember |  |
Other noncurrent liabilities | 0 us-gaap_OtherLiabilitiesNoncurrent / dei_LegalEntityAxis = cmcsa_CombinedCchmoParentsMember | 0 us-gaap_OtherLiabilitiesNoncurrent / dei_LegalEntityAxis = cmcsa_CombinedCchmoParentsMember |  |
Redeemable noncontrolling interests and redeemable subsidiary preferred stock | 0 cmcsa_RedeemableNoncontrollingInterestsAndRedeemableSubsidiaryPreferredStock / dei_LegalEntityAxis = cmcsa_CombinedCchmoParentsMember | 0 cmcsa_RedeemableNoncontrollingInterestsAndRedeemableSubsidiaryPreferredStock / dei_LegalEntityAxis = cmcsa_CombinedCchmoParentsMember |  |
Common stock | 0 us-gaap_CommonStockValue / dei_LegalEntityAxis = cmcsa_CombinedCchmoParentsMember | 0 us-gaap_CommonStockValue / dei_LegalEntityAxis = cmcsa_CombinedCchmoParentsMember |  |
Other shareholders' equity | 57,130,000,000 cmcsa_OtherStockholdersEquity / dei_LegalEntityAxis = cmcsa_CombinedCchmoParentsMember | 53,172,000,000 cmcsa_OtherStockholdersEquity / dei_LegalEntityAxis = cmcsa_CombinedCchmoParentsMember |  |
Total Comcast Corporation shareholders' equity | 57,130,000,000 us-gaap_StockholdersEquity / dei_LegalEntityAxis = cmcsa_CombinedCchmoParentsMember | 53,172,000,000 us-gaap_StockholdersEquity / dei_LegalEntityAxis = cmcsa_CombinedCchmoParentsMember |  |
Noncontrolling interests | 0 us-gaap_MinorityInterest / dei_LegalEntityAxis = cmcsa_CombinedCchmoParentsMember | 0 us-gaap_MinorityInterest / dei_LegalEntityAxis = cmcsa_CombinedCchmoParentsMember |  |
Total equity | 57,130,000,000 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest / dei_LegalEntityAxis = cmcsa_CombinedCchmoParentsMember | 53,172,000,000 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest / dei_LegalEntityAxis = cmcsa_CombinedCchmoParentsMember |  |
Total liabilities and equity | 58,677,000,000 us-gaap_LiabilitiesAndStockholdersEquity / dei_LegalEntityAxis = cmcsa_CombinedCchmoParentsMember | 54,724,000,000 us-gaap_LiabilitiesAndStockholdersEquity / dei_LegalEntityAxis = cmcsa_CombinedCchmoParentsMember |  |
NBCUniversal Media Parent [Member] |  |  |  |
Cash and cash equivalents | 385,000,000 us-gaap_CashAndCashEquivalentsAtCarryingValue / dei_LegalEntityAxis = cmcsa_NbcuniversalMediaParentMember | 336,000,000 us-gaap_CashAndCashEquivalentsAtCarryingValue / dei_LegalEntityAxis = cmcsa_NbcuniversalMediaParentMember | 5,129,000,000 us-gaap_CashAndCashEquivalentsAtCarryingValue / dei_LegalEntityAxis = cmcsa_NbcuniversalMediaParentMember | 238,000,000 us-gaap_CashAndCashEquivalentsAtCarryingValue / dei_LegalEntityAxis = cmcsa_NbcuniversalMediaParentMember
Investments [Current] | 0 us-gaap_ShortTermInvestments / dei_LegalEntityAxis = cmcsa_NbcuniversalMediaParentMember | 0 us-gaap_ShortTermInvestments / dei_LegalEntityAxis = cmcsa_NbcuniversalMediaParentMember |  |
Receivables, net | 0 us-gaap_AccountsReceivableNetCurrent / dei_LegalEntityAxis = cmcsa_NbcuniversalMediaParentMember | 0 us-gaap_AccountsReceivableNetCurrent / dei_LegalEntityAxis = cmcsa_NbcuniversalMediaParentMember |  |
Programming rights | 0 cmcsa_ProgrammingRightsCurrent / dei_LegalEntityAxis = cmcsa_NbcuniversalMediaParentMember | 0 cmcsa_ProgrammingRightsCurrent / dei_LegalEntityAxis = cmcsa_NbcuniversalMediaParentMember |  |
Other current assets | 41,000,000 us-gaap_OtherAssetsCurrent / dei_LegalEntityAxis = cmcsa_NbcuniversalMediaParentMember | 35,000,000 us-gaap_OtherAssetsCurrent / dei_LegalEntityAxis = cmcsa_NbcuniversalMediaParentMember |  |
Total current assets | 426,000,000 us-gaap_AssetsCurrent / dei_LegalEntityAxis = cmcsa_NbcuniversalMediaParentMember | 371,000,000 us-gaap_AssetsCurrent / dei_LegalEntityAxis = cmcsa_NbcuniversalMediaParentMember |  |
Film and television costs | 0 cmcsa_FilmAndTelevisionCosts / dei_LegalEntityAxis = cmcsa_NbcuniversalMediaParentMember | 0 cmcsa_FilmAndTelevisionCosts / dei_LegalEntityAxis = cmcsa_NbcuniversalMediaParentMember |  |
Investments | 378,000,000 us-gaap_LongTermInvestments / dei_LegalEntityAxis = cmcsa_NbcuniversalMediaParentMember | 374,000,000 us-gaap_LongTermInvestments / dei_LegalEntityAxis = cmcsa_NbcuniversalMediaParentMember |  |
Investments in and amounts due from subsidiaries eliminated upon consolidation | 41,239,000,000 cmcsa_InvestmentsInAndAmountsDueFromSubsidiariesEliminatedUponConsolidation / dei_LegalEntityAxis = cmcsa_NbcuniversalMediaParentMember | 40,644,000,000 cmcsa_InvestmentsInAndAmountsDueFromSubsidiariesEliminatedUponConsolidation / dei_LegalEntityAxis = cmcsa_NbcuniversalMediaParentMember |  |
Property and equipment, net | 0 us-gaap_PropertyPlantAndEquipmentNet / dei_LegalEntityAxis = cmcsa_NbcuniversalMediaParentMember | 0 us-gaap_PropertyPlantAndEquipmentNet / dei_LegalEntityAxis = cmcsa_NbcuniversalMediaParentMember |  |
Franchise rights | 0 us-gaap_IndefiniteLivedFranchiseRights / dei_LegalEntityAxis = cmcsa_NbcuniversalMediaParentMember | 0 us-gaap_IndefiniteLivedFranchiseRights / dei_LegalEntityAxis = cmcsa_NbcuniversalMediaParentMember |  |
Goodwill | 0 us-gaap_Goodwill / dei_LegalEntityAxis = cmcsa_NbcuniversalMediaParentMember | 0 us-gaap_Goodwill / dei_LegalEntityAxis = cmcsa_NbcuniversalMediaParentMember |  |
Other intangible assets, net | 0 us-gaap_OtherIntangibleAssetsNet / dei_LegalEntityAxis = cmcsa_NbcuniversalMediaParentMember | 0 us-gaap_OtherIntangibleAssetsNet / dei_LegalEntityAxis = cmcsa_NbcuniversalMediaParentMember |  |
Other noncurrent assets, net | 92,000,000 us-gaap_OtherAssetsNoncurrent / dei_LegalEntityAxis = cmcsa_NbcuniversalMediaParentMember | 103,000,000 us-gaap_OtherAssetsNoncurrent / dei_LegalEntityAxis = cmcsa_NbcuniversalMediaParentMember |  |
Total assets | 42,135,000,000 us-gaap_Assets / dei_LegalEntityAxis = cmcsa_NbcuniversalMediaParentMember | 41,492,000,000 us-gaap_Assets / dei_LegalEntityAxis = cmcsa_NbcuniversalMediaParentMember |  |
Accounts payable and accrued expenses related to trade creditors | 0 us-gaap_AccountsPayableCurrent / dei_LegalEntityAxis = cmcsa_NbcuniversalMediaParentMember | 0 us-gaap_AccountsPayableCurrent / dei_LegalEntityAxis = cmcsa_NbcuniversalMediaParentMember |  |
Accrued participations and residuals | 0 cmcsa_AccruedParticipationsAndResidualsCurrent / dei_LegalEntityAxis = cmcsa_NbcuniversalMediaParentMember | 0 cmcsa_AccruedParticipationsAndResidualsCurrent / dei_LegalEntityAxis = cmcsa_NbcuniversalMediaParentMember |  |
Accrued expenses and other current liabilities [condensed] | 331,000,000 cmcsa_AccruedExpensesAndOtherCurrentLiabilitiesIncludingDeferredRevenue / dei_LegalEntityAxis = cmcsa_NbcuniversalMediaParentMember | 323,000,000 cmcsa_AccruedExpensesAndOtherCurrentLiabilitiesIncludingDeferredRevenue / dei_LegalEntityAxis = cmcsa_NbcuniversalMediaParentMember |  |
Current portion of long-term debt | 1,006,000,000 us-gaap_DebtCurrent / dei_LegalEntityAxis = cmcsa_NbcuniversalMediaParentMember | 903,000,000 us-gaap_DebtCurrent / dei_LegalEntityAxis = cmcsa_NbcuniversalMediaParentMember |  |
Total current liabilities | 1,337,000,000 us-gaap_LiabilitiesCurrent / dei_LegalEntityAxis = cmcsa_NbcuniversalMediaParentMember | 1,226,000,000 us-gaap_LiabilitiesCurrent / dei_LegalEntityAxis = cmcsa_NbcuniversalMediaParentMember |  |
Long-term debt, less current portion | 9,218,000,000 us-gaap_LongTermDebtAndCapitalLeaseObligations / dei_LegalEntityAxis = cmcsa_NbcuniversalMediaParentMember | 10,236,000,000 us-gaap_LongTermDebtAndCapitalLeaseObligations / dei_LegalEntityAxis = cmcsa_NbcuniversalMediaParentMember |  |
Deferred income taxes | 67,000,000 us-gaap_DeferredTaxLiabilitiesNoncurrent / dei_LegalEntityAxis = cmcsa_NbcuniversalMediaParentMember | 59,000,000 us-gaap_DeferredTaxLiabilitiesNoncurrent / dei_LegalEntityAxis = cmcsa_NbcuniversalMediaParentMember |  |
Other noncurrent liabilities | 1,143,000,000 us-gaap_OtherLiabilitiesNoncurrent / dei_LegalEntityAxis = cmcsa_NbcuniversalMediaParentMember | 931,000,000 us-gaap_OtherLiabilitiesNoncurrent / dei_LegalEntityAxis = cmcsa_NbcuniversalMediaParentMember |  |
Redeemable noncontrolling interests and redeemable subsidiary preferred stock | 0 cmcsa_RedeemableNoncontrollingInterestsAndRedeemableSubsidiaryPreferredStock / dei_LegalEntityAxis = cmcsa_NbcuniversalMediaParentMember | 0 cmcsa_RedeemableNoncontrollingInterestsAndRedeemableSubsidiaryPreferredStock / dei_LegalEntityAxis = cmcsa_NbcuniversalMediaParentMember |  |
Common stock | 0 us-gaap_CommonStockValue / dei_LegalEntityAxis = cmcsa_NbcuniversalMediaParentMember | 0 us-gaap_CommonStockValue / dei_LegalEntityAxis = cmcsa_NbcuniversalMediaParentMember |  |
Other shareholders' equity | 30,370,000,000 cmcsa_OtherStockholdersEquity / dei_LegalEntityAxis = cmcsa_NbcuniversalMediaParentMember | 29,040,000,000 cmcsa_OtherStockholdersEquity / dei_LegalEntityAxis = cmcsa_NbcuniversalMediaParentMember |  |
Total Comcast Corporation shareholders' equity | 30,370,000,000 us-gaap_StockholdersEquity / dei_LegalEntityAxis = cmcsa_NbcuniversalMediaParentMember | 29,040,000,000 us-gaap_StockholdersEquity / dei_LegalEntityAxis = cmcsa_NbcuniversalMediaParentMember |  |
Noncontrolling interests | 0 us-gaap_MinorityInterest / dei_LegalEntityAxis = cmcsa_NbcuniversalMediaParentMember | 0 us-gaap_MinorityInterest / dei_LegalEntityAxis = cmcsa_NbcuniversalMediaParentMember |  |
Total equity | 30,370,000,000 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest / dei_LegalEntityAxis = cmcsa_NbcuniversalMediaParentMember | 29,040,000,000 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest / dei_LegalEntityAxis = cmcsa_NbcuniversalMediaParentMember |  |
Total liabilities and equity | 42,135,000,000 us-gaap_LiabilitiesAndStockholdersEquity / dei_LegalEntityAxis = cmcsa_NbcuniversalMediaParentMember | 41,492,000,000 us-gaap_LiabilitiesAndStockholdersEquity / dei_LegalEntityAxis = cmcsa_NbcuniversalMediaParentMember |  |
Comcast Non-Guarantor Subsidiaries [Member] |  |  |  |
Cash and cash equivalents | 3,525,000,000 us-gaap_CashAndCashEquivalentsAtCarryingValue / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember | 1,382,000,000 us-gaap_CashAndCashEquivalentsAtCarryingValue / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember | 5,822,000,000 us-gaap_CashAndCashEquivalentsAtCarryingValue / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember | 1,382,000,000 us-gaap_CashAndCashEquivalentsAtCarryingValue / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember
Investments [Current] | 602,000,000 us-gaap_ShortTermInvestments / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember | 3,573,000,000 us-gaap_ShortTermInvestments / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember |  |
Receivables, net | 6,321,000,000 us-gaap_AccountsReceivableNetCurrent / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember | 6,376,000,000 us-gaap_AccountsReceivableNetCurrent / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember |  |
Programming rights | 839,000,000 cmcsa_ProgrammingRightsCurrent / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember | 928,000,000 cmcsa_ProgrammingRightsCurrent / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember |  |
Other current assets | 1,551,000,000 us-gaap_OtherAssetsCurrent / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember | 1,208,000,000 us-gaap_OtherAssetsCurrent / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember |  |
Total current assets | 12,838,000,000 us-gaap_AssetsCurrent / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember | 13,467,000,000 us-gaap_AssetsCurrent / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember |  |
Film and television costs | 5,727,000,000 cmcsa_FilmAndTelevisionCosts / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember | 4,994,000,000 cmcsa_FilmAndTelevisionCosts / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember |  |
Investments | 2,721,000,000 us-gaap_LongTermInvestments / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember | 3,385,000,000 us-gaap_LongTermInvestments / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember |  |
Investments in and amounts due from subsidiaries eliminated upon consolidation | 98,152,000,000 cmcsa_InvestmentsInAndAmountsDueFromSubsidiariesEliminatedUponConsolidation / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember | 85,164,000,000 cmcsa_InvestmentsInAndAmountsDueFromSubsidiariesEliminatedUponConsolidation / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember |  |
Property and equipment, net | 30,754,000,000 us-gaap_PropertyPlantAndEquipmentNet / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember | 29,620,000,000 us-gaap_PropertyPlantAndEquipmentNet / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember |  |
Franchise rights | 59,364,000,000 us-gaap_IndefiniteLivedFranchiseRights / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember | 59,364,000,000 us-gaap_IndefiniteLivedFranchiseRights / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember |  |
Goodwill | 27,316,000,000 us-gaap_Goodwill / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember | 27,098,000,000 us-gaap_Goodwill / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember |  |
Other intangible assets, net | 16,969,000,000 us-gaap_OtherIntangibleAssetsNet / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember | 17,318,000,000 us-gaap_OtherIntangibleAssetsNet / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember |  |
Other noncurrent assets, net | 1,949,000,000 us-gaap_OtherAssetsNoncurrent / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember | 1,899,000,000 us-gaap_OtherAssetsNoncurrent / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember |  |
Total assets | 255,790,000,000 us-gaap_Assets / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember | 242,309,000,000 us-gaap_Assets / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember |  |
Accounts payable and accrued expenses related to trade creditors | 5,618,000,000 us-gaap_AccountsPayableCurrent / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember | 5,520,000,000 us-gaap_AccountsPayableCurrent / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember |  |
Accrued participations and residuals | 1,347,000,000 cmcsa_AccruedParticipationsAndResidualsCurrent / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember | 1,239,000,000 cmcsa_AccruedParticipationsAndResidualsCurrent / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember |  |
Accrued expenses and other current liabilities [condensed] | 3,767,000,000 cmcsa_AccruedExpensesAndOtherCurrentLiabilitiesIncludingDeferredRevenue / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember | 6,678,000,000 cmcsa_AccruedExpensesAndOtherCurrentLiabilitiesIncludingDeferredRevenue / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember |  |
Current portion of long-term debt | 884,000,000 us-gaap_DebtCurrent / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember | 26,000,000 us-gaap_DebtCurrent / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember |  |
Total current liabilities | 11,616,000,000 us-gaap_LiabilitiesCurrent / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember | 13,463,000,000 us-gaap_LiabilitiesCurrent / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember |  |
Long-term debt, less current portion | 4,408,000,000 us-gaap_LongTermDebtAndCapitalLeaseObligations / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember | 5,697,000,000 us-gaap_LongTermDebtAndCapitalLeaseObligations / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember |  |
Deferred income taxes | 33,127,000,000 us-gaap_DeferredTaxLiabilitiesNoncurrent / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember | 31,840,000,000 us-gaap_DeferredTaxLiabilitiesNoncurrent / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember |  |
Other noncurrent liabilities | 7,484,000,000 us-gaap_OtherLiabilitiesNoncurrent / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember | 8,675,000,000 us-gaap_OtherLiabilitiesNoncurrent / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember |  |
Redeemable noncontrolling interests and redeemable subsidiary preferred stock | 1,066,000,000 cmcsa_RedeemableNoncontrollingInterestsAndRedeemableSubsidiaryPreferredStock / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember | 957,000,000 cmcsa_RedeemableNoncontrollingInterestsAndRedeemableSubsidiaryPreferredStock / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember |  |
Common stock | 0 us-gaap_CommonStockValue / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember | 0 us-gaap_CommonStockValue / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember |  |
Other shareholders' equity | 197,732,000,000 cmcsa_OtherStockholdersEquity / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember | 181,313,000,000 cmcsa_OtherStockholdersEquity / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember |  |
Total Comcast Corporation shareholders' equity | 197,732,000,000 us-gaap_StockholdersEquity / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember | 181,313,000,000 us-gaap_StockholdersEquity / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember |  |
Noncontrolling interests | 357,000,000 us-gaap_MinorityInterest / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember | 364,000,000 us-gaap_MinorityInterest / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember |  |
Total equity | 198,089,000,000 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember | 181,677,000,000 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember |  |
Total liabilities and equity | $ 255,790,000,000 us-gaap_LiabilitiesAndStockholdersEquity / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember | $ 242,309,000,000 us-gaap_LiabilitiesAndStockholdersEquity / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember |  |

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