v2.4.1.9

Condensed Consolidating Financial Information (Condensed Consolidating Balance Sheet) (Details) (USD $) In Millions, unless otherwise specified | Mar. 31, 2015 | Dec. 31, 2014 | Mar. 31, 2014 | Dec. 31, 2013
--- | --- | --- | --- | ---
Cash and cash equivalents | $ 3,937 us-gaap_CashAndCashEquivalentsAtCarryingValue | $ 3,910 us-gaap_CashAndCashEquivalentsAtCarryingValue | $ 3,054 us-gaap_CashAndCashEquivalentsAtCarryingValue | $ 1,718 us-gaap_CashAndCashEquivalentsAtCarryingValue
Investments [Current] | 158 us-gaap_ShortTermInvestments | 602 us-gaap_ShortTermInvestments |  |
Receivables, net | 6,144 us-gaap_AccountsReceivableNetCurrent | 6,321 us-gaap_AccountsReceivableNetCurrent |  |
Programming rights | 945 cmcsa_ProgrammingRightsCurrent | 839 cmcsa_ProgrammingRightsCurrent |  |
Other current assets | 1,737 us-gaap_OtherAssetsCurrent | 1,859 us-gaap_OtherAssetsCurrent |  |
Total current assets | 12,921 us-gaap_AssetsCurrent | 13,531 us-gaap_AssetsCurrent |  |
Film and television costs | 5,637 cmcsa_FilmAndTelevisionCosts | 5,727 cmcsa_FilmAndTelevisionCosts |  |
Investments | 3,235 us-gaap_LongTermInvestments | 3,135 us-gaap_LongTermInvestments |  |
Investments in and amounts due from subsidiaries eliminated upon consolidation | 0 cmcsa_InvestmentsInAndAmountsDueFromSubsidiariesEliminatedUponConsolidation | 0 cmcsa_InvestmentsInAndAmountsDueFromSubsidiariesEliminatedUponConsolidation |  |
Property and equipment, net | 31,127 us-gaap_PropertyPlantAndEquipmentNet | 30,953 us-gaap_PropertyPlantAndEquipmentNet |  |
Franchise rights | 59,364 us-gaap_IndefiniteLivedFranchiseRights | 59,364 us-gaap_IndefiniteLivedFranchiseRights |  |
Goodwill | 27,302 us-gaap_Goodwill | 27,316 us-gaap_Goodwill |  |
Other intangible assets, net | 16,852 us-gaap_OtherIntangibleAssetsNet | 16,980 us-gaap_OtherIntangibleAssetsNet |  |
Other noncurrent assets, net | 2,319 us-gaap_OtherAssetsNoncurrent | 2,333 us-gaap_OtherAssetsNoncurrent |  |
Total assets | 158,757 us-gaap_Assets | 159,339 us-gaap_Assets |  |
Accounts payable and accrued expenses related to trade creditors | 6,157 us-gaap_AccountsPayableCurrent | 5,638 us-gaap_AccountsPayableCurrent |  |
Accrued participations and residuals | 1,387 cmcsa_AccruedParticipationsAndResidualsCurrent | 1,347 cmcsa_AccruedParticipationsAndResidualsCurrent |  |
Accrued expenses and other current liabilities [condensed] | 6,778 cmcsa_AccruedExpensesAndOtherCurrentLiabilitiesIncludingDeferredRevenue | 6,208 cmcsa_AccruedExpensesAndOtherCurrentLiabilitiesIncludingDeferredRevenue |  |
Current portion of long-term debt | 4,180 us-gaap_DebtCurrent | 4,217 us-gaap_DebtCurrent |  |
Total current liabilities | 18,502 us-gaap_LiabilitiesCurrent | 17,410 us-gaap_LiabilitiesCurrent |  |
Long-term debt, less current portion | 42,953 us-gaap_LongTermDebtAndCapitalLeaseObligations | 44,017 us-gaap_LongTermDebtAndCapitalLeaseObligations |  |
Deferred income taxes | 32,855 us-gaap_DeferredTaxLiabilitiesNoncurrent | 32,959 us-gaap_DeferredTaxLiabilitiesNoncurrent |  |
Other noncurrent liabilities | 10,837 us-gaap_OtherLiabilitiesNoncurrent | 10,819 us-gaap_OtherLiabilitiesNoncurrent |  |
Redeemable noncontrolling interests and redeemable subsidiary preferred stock | 1,099 cmcsa_RedeemableNoncontrollingInterestsAndRedeemableSubsidiaryPreferredStock | 1,066 cmcsa_RedeemableNoncontrollingInterestsAndRedeemableSubsidiaryPreferredStock |  |
Common stock | 30 us-gaap_CommonStockValue | 30 us-gaap_CommonStockValue |  |
Other shareholders' equity | 52,141 cmcsa_OtherStockholdersEquity | 52,681 cmcsa_OtherStockholdersEquity |  |
Total Comcast Corporation shareholders' equity | 52,171 us-gaap_StockholdersEquity | 52,711 us-gaap_StockholdersEquity |  |
Noncontrolling interests | 340 us-gaap_MinorityInterest | 357 us-gaap_MinorityInterest |  |
Total equity | 52,511 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest | 53,068 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest | 51,632 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest | 51,058 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest
Total liabilities and equity | 158,757 us-gaap_LiabilitiesAndStockholdersEquity | 159,339 us-gaap_LiabilitiesAndStockholdersEquity |  |
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 | 279 us-gaap_OtherAssetsCurrent / dei_LegalEntityAxis = us-gaap_ParentCompanyMember | 267 us-gaap_OtherAssetsCurrent / dei_LegalEntityAxis = us-gaap_ParentCompanyMember |  |
Total current assets | 279 us-gaap_AssetsCurrent / dei_LegalEntityAxis = us-gaap_ParentCompanyMember | 267 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 | 31 us-gaap_LongTermInvestments / dei_LegalEntityAxis = us-gaap_ParentCompanyMember | 36 us-gaap_LongTermInvestments / dei_LegalEntityAxis = us-gaap_ParentCompanyMember |  |
Investments in and amounts due from subsidiaries eliminated upon consolidation | 82,713 cmcsa_InvestmentsInAndAmountsDueFromSubsidiariesEliminatedUponConsolidation / dei_LegalEntityAxis = us-gaap_ParentCompanyMember | 84,142 cmcsa_InvestmentsInAndAmountsDueFromSubsidiariesEliminatedUponConsolidation / dei_LegalEntityAxis = us-gaap_ParentCompanyMember |  |
Property and equipment, net | 200 us-gaap_PropertyPlantAndEquipmentNet / dei_LegalEntityAxis = us-gaap_ParentCompanyMember | 199 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 | 10 us-gaap_OtherIntangibleAssetsNet / dei_LegalEntityAxis = us-gaap_ParentCompanyMember | 11 us-gaap_OtherIntangibleAssetsNet / dei_LegalEntityAxis = us-gaap_ParentCompanyMember |  |
Other noncurrent assets, net | 1,201 us-gaap_OtherAssetsNoncurrent / dei_LegalEntityAxis = us-gaap_ParentCompanyMember | 1,224 us-gaap_OtherAssetsNoncurrent / dei_LegalEntityAxis = us-gaap_ParentCompanyMember |  |
Total assets | 84,434 us-gaap_Assets / dei_LegalEntityAxis = us-gaap_ParentCompanyMember | 85,879 us-gaap_Assets / dei_LegalEntityAxis = us-gaap_ParentCompanyMember |  |
Accounts payable and accrued expenses related to trade creditors | 7 us-gaap_AccountsPayableCurrent / dei_LegalEntityAxis = us-gaap_ParentCompanyMember | 19 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] | 1,534 cmcsa_AccruedExpensesAndOtherCurrentLiabilitiesIncludingDeferredRevenue / dei_LegalEntityAxis = us-gaap_ParentCompanyMember | 1,547 cmcsa_AccruedExpensesAndOtherCurrentLiabilitiesIncludingDeferredRevenue / dei_LegalEntityAxis = us-gaap_ParentCompanyMember |  |
Current portion of long-term debt | 1,761 us-gaap_DebtCurrent / dei_LegalEntityAxis = us-gaap_ParentCompanyMember | 1,650 us-gaap_DebtCurrent / dei_LegalEntityAxis = us-gaap_ParentCompanyMember |  |
Total current liabilities | 3,302 us-gaap_LiabilitiesCurrent / dei_LegalEntityAxis = us-gaap_ParentCompanyMember | 3,216 us-gaap_LiabilitiesCurrent / dei_LegalEntityAxis = us-gaap_ParentCompanyMember |  |
Long-term debt, less current portion | 26,566 us-gaap_LongTermDebtAndCapitalLeaseObligations / dei_LegalEntityAxis = us-gaap_ParentCompanyMember | 27,616 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 | 2,395 us-gaap_OtherLiabilitiesNoncurrent / dei_LegalEntityAxis = us-gaap_ParentCompanyMember | 2,336 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 us-gaap_CommonStockValue / dei_LegalEntityAxis = us-gaap_ParentCompanyMember | 30 us-gaap_CommonStockValue / dei_LegalEntityAxis = us-gaap_ParentCompanyMember |  |
Other shareholders' equity | 52,141 cmcsa_OtherStockholdersEquity / dei_LegalEntityAxis = us-gaap_ParentCompanyMember | 52,681 cmcsa_OtherStockholdersEquity / dei_LegalEntityAxis = us-gaap_ParentCompanyMember |  |
Total Comcast Corporation shareholders' equity | 52,171 us-gaap_StockholdersEquity / dei_LegalEntityAxis = us-gaap_ParentCompanyMember | 52,711 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 | 52,171 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest / dei_LegalEntityAxis = us-gaap_ParentCompanyMember | 52,711 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest / dei_LegalEntityAxis = us-gaap_ParentCompanyMember |  |
Total liabilities and equity | 84,434 us-gaap_LiabilitiesAndStockholdersEquity / dei_LegalEntityAxis = us-gaap_ParentCompanyMember | 85,879 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 | 105,551 cmcsa_InvestmentsInAndAmountsDueFromSubsidiariesEliminatedUponConsolidation / dei_LegalEntityAxis = cmcsa_ComcastHoldingsMember | 103,420 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 us-gaap_OtherAssetsNoncurrent / dei_LegalEntityAxis = cmcsa_ComcastHoldingsMember | 148 us-gaap_OtherAssetsNoncurrent / dei_LegalEntityAxis = cmcsa_ComcastHoldingsMember |  |
Total assets | 105,699 us-gaap_Assets / dei_LegalEntityAxis = cmcsa_ComcastHoldingsMember | 103,568 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 cmcsa_AccruedExpensesAndOtherCurrentLiabilitiesIncludingDeferredRevenue / dei_LegalEntityAxis = cmcsa_ComcastHoldingsMember | 283 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 us-gaap_LiabilitiesCurrent / dei_LegalEntityAxis = cmcsa_ComcastHoldingsMember | 283 us-gaap_LiabilitiesCurrent / dei_LegalEntityAxis = cmcsa_ComcastHoldingsMember |  |
Long-term debt, less current portion | 126 us-gaap_LongTermDebtAndCapitalLeaseObligations / dei_LegalEntityAxis = cmcsa_ComcastHoldingsMember | 126 us-gaap_LongTermDebtAndCapitalLeaseObligations / dei_LegalEntityAxis = cmcsa_ComcastHoldingsMember |  |
Deferred income taxes | 682 us-gaap_DeferredTaxLiabilitiesNoncurrent / dei_LegalEntityAxis = cmcsa_ComcastHoldingsMember | 701 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 | 104,608 cmcsa_OtherStockholdersEquity / dei_LegalEntityAxis = cmcsa_ComcastHoldingsMember | 102,458 cmcsa_OtherStockholdersEquity / dei_LegalEntityAxis = cmcsa_ComcastHoldingsMember |  |
Total Comcast Corporation shareholders' equity | 104,608 us-gaap_StockholdersEquity / dei_LegalEntityAxis = cmcsa_ComcastHoldingsMember | 102,458 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 | 104,608 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest / dei_LegalEntityAxis = cmcsa_ComcastHoldingsMember | 102,458 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest / dei_LegalEntityAxis = cmcsa_ComcastHoldingsMember |  |
Total liabilities and equity | 105,699 us-gaap_LiabilitiesAndStockholdersEquity / dei_LegalEntityAxis = cmcsa_ComcastHoldingsMember | 103,568 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 | 112,432 cmcsa_InvestmentsInAndAmountsDueFromSubsidiariesEliminatedUponConsolidation / dei_LegalEntityAxis = cmcsa_CcclParentMember | 110,323 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 | 112,432 us-gaap_Assets / dei_LegalEntityAxis = cmcsa_CcclParentMember | 110,323 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] | 343 cmcsa_AccruedExpensesAndOtherCurrentLiabilitiesIncludingDeferredRevenue / dei_LegalEntityAxis = cmcsa_CcclParentMember | 233 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 | 343 us-gaap_LiabilitiesCurrent / dei_LegalEntityAxis = cmcsa_CcclParentMember | 233 us-gaap_LiabilitiesCurrent / dei_LegalEntityAxis = cmcsa_CcclParentMember |  |
Long-term debt, less current portion | 1,828 us-gaap_LongTermDebtAndCapitalLeaseObligations / dei_LegalEntityAxis = cmcsa_CcclParentMember | 1,827 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 | 110,261 cmcsa_OtherStockholdersEquity / dei_LegalEntityAxis = cmcsa_CcclParentMember | 108,263 cmcsa_OtherStockholdersEquity / dei_LegalEntityAxis = cmcsa_CcclParentMember |  |
Total Comcast Corporation shareholders' equity | 110,261 us-gaap_StockholdersEquity / dei_LegalEntityAxis = cmcsa_CcclParentMember | 108,263 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 | 110,261 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest / dei_LegalEntityAxis = cmcsa_CcclParentMember | 108,263 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest / dei_LegalEntityAxis = cmcsa_CcclParentMember |  |
Total liabilities and equity | 112,432 us-gaap_LiabilitiesAndStockholdersEquity / dei_LegalEntityAxis = cmcsa_CcclParentMember | 110,323 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 | 60,289 cmcsa_InvestmentsInAndAmountsDueFromSubsidiariesEliminatedUponConsolidation / dei_LegalEntityAxis = cmcsa_CombinedCchmoParentsMember | 58,677 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 | 60,289 us-gaap_Assets / dei_LegalEntityAxis = cmcsa_CombinedCchmoParentsMember | 58,677 us-gaap_Assets / dei_LegalEntityAxis = cmcsa_CombinedCchmoParentsMember |  |
Accounts payable and accrued expenses related to trade creditors | 0 us-gaap_AccountsPayableCurrent / dei_LegalEntityAxis = cmcsa_CombinedCchmoParentsMember | 1 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] | 21 cmcsa_AccruedExpensesAndOtherCurrentLiabilitiesIncludingDeferredRevenue / dei_LegalEntityAxis = cmcsa_CombinedCchmoParentsMember | 47 cmcsa_AccruedExpensesAndOtherCurrentLiabilitiesIncludingDeferredRevenue / dei_LegalEntityAxis = cmcsa_CombinedCchmoParentsMember |  |
Current portion of long-term debt | 676 us-gaap_DebtCurrent / dei_LegalEntityAxis = cmcsa_CombinedCchmoParentsMember | 677 us-gaap_DebtCurrent / dei_LegalEntityAxis = cmcsa_CombinedCchmoParentsMember |  |
Total current liabilities | 697 us-gaap_LiabilitiesCurrent / dei_LegalEntityAxis = cmcsa_CombinedCchmoParentsMember | 725 us-gaap_LiabilitiesCurrent / dei_LegalEntityAxis = cmcsa_CombinedCchmoParentsMember |  |
Long-term debt, less current portion | 822 us-gaap_LongTermDebtAndCapitalLeaseObligations / dei_LegalEntityAxis = cmcsa_CombinedCchmoParentsMember | 822 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 | 58,770 cmcsa_OtherStockholdersEquity / dei_LegalEntityAxis = cmcsa_CombinedCchmoParentsMember | 57,130 cmcsa_OtherStockholdersEquity / dei_LegalEntityAxis = cmcsa_CombinedCchmoParentsMember |  |
Total Comcast Corporation shareholders' equity | 58,770 us-gaap_StockholdersEquity / dei_LegalEntityAxis = cmcsa_CombinedCchmoParentsMember | 57,130 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 | 58,770 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest / dei_LegalEntityAxis = cmcsa_CombinedCchmoParentsMember | 57,130 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest / dei_LegalEntityAxis = cmcsa_CombinedCchmoParentsMember |  |
Total liabilities and equity | 60,289 us-gaap_LiabilitiesAndStockholdersEquity / dei_LegalEntityAxis = cmcsa_CombinedCchmoParentsMember | 58,677 us-gaap_LiabilitiesAndStockholdersEquity / dei_LegalEntityAxis = cmcsa_CombinedCchmoParentsMember |  |
NBCUniversal Media Parent [Member] |  |  |  |
Cash and cash equivalents | 339 us-gaap_CashAndCashEquivalentsAtCarryingValue / dei_LegalEntityAxis = cmcsa_NbcuniversalMediaParentMember | 385 us-gaap_CashAndCashEquivalentsAtCarryingValue / dei_LegalEntityAxis = cmcsa_NbcuniversalMediaParentMember | 506 us-gaap_CashAndCashEquivalentsAtCarryingValue / dei_LegalEntityAxis = cmcsa_NbcuniversalMediaParentMember | 336 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 | 64 us-gaap_OtherAssetsCurrent / dei_LegalEntityAxis = cmcsa_NbcuniversalMediaParentMember | 41 us-gaap_OtherAssetsCurrent / dei_LegalEntityAxis = cmcsa_NbcuniversalMediaParentMember |  |
Total current assets | 403 us-gaap_AssetsCurrent / dei_LegalEntityAxis = cmcsa_NbcuniversalMediaParentMember | 426 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 | 372 us-gaap_LongTermInvestments / dei_LegalEntityAxis = cmcsa_NbcuniversalMediaParentMember | 378 us-gaap_LongTermInvestments / dei_LegalEntityAxis = cmcsa_NbcuniversalMediaParentMember |  |
Investments in and amounts due from subsidiaries eliminated upon consolidation | 41,900 cmcsa_InvestmentsInAndAmountsDueFromSubsidiariesEliminatedUponConsolidation / dei_LegalEntityAxis = cmcsa_NbcuniversalMediaParentMember | 41,239 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 | 97 us-gaap_OtherAssetsNoncurrent / dei_LegalEntityAxis = cmcsa_NbcuniversalMediaParentMember | 92 us-gaap_OtherAssetsNoncurrent / dei_LegalEntityAxis = cmcsa_NbcuniversalMediaParentMember |  |
Total assets | 42,772 us-gaap_Assets / dei_LegalEntityAxis = cmcsa_NbcuniversalMediaParentMember | 42,135 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] | 407 cmcsa_AccruedExpensesAndOtherCurrentLiabilitiesIncludingDeferredRevenue / dei_LegalEntityAxis = cmcsa_NbcuniversalMediaParentMember | 331 cmcsa_AccruedExpensesAndOtherCurrentLiabilitiesIncludingDeferredRevenue / dei_LegalEntityAxis = cmcsa_NbcuniversalMediaParentMember |  |
Current portion of long-term debt | 1,003 us-gaap_DebtCurrent / dei_LegalEntityAxis = cmcsa_NbcuniversalMediaParentMember | 1,006 us-gaap_DebtCurrent / dei_LegalEntityAxis = cmcsa_NbcuniversalMediaParentMember |  |
Total current liabilities | 1,410 us-gaap_LiabilitiesCurrent / dei_LegalEntityAxis = cmcsa_NbcuniversalMediaParentMember | 1,337 us-gaap_LiabilitiesCurrent / dei_LegalEntityAxis = cmcsa_NbcuniversalMediaParentMember |  |
Long-term debt, less current portion | 9,217 us-gaap_LongTermDebtAndCapitalLeaseObligations / dei_LegalEntityAxis = cmcsa_NbcuniversalMediaParentMember | 9,218 us-gaap_LongTermDebtAndCapitalLeaseObligations / dei_LegalEntityAxis = cmcsa_NbcuniversalMediaParentMember |  |
Deferred income taxes | 67 us-gaap_DeferredTaxLiabilitiesNoncurrent / dei_LegalEntityAxis = cmcsa_NbcuniversalMediaParentMember | 67 us-gaap_DeferredTaxLiabilitiesNoncurrent / dei_LegalEntityAxis = cmcsa_NbcuniversalMediaParentMember |  |
Other noncurrent liabilities | 1,103 us-gaap_OtherLiabilitiesNoncurrent / dei_LegalEntityAxis = cmcsa_NbcuniversalMediaParentMember | 1,143 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 | 30,975 cmcsa_OtherStockholdersEquity / dei_LegalEntityAxis = cmcsa_NbcuniversalMediaParentMember | 30,370 cmcsa_OtherStockholdersEquity / dei_LegalEntityAxis = cmcsa_NbcuniversalMediaParentMember |  |
Total Comcast Corporation shareholders' equity | 30,975 us-gaap_StockholdersEquity / dei_LegalEntityAxis = cmcsa_NbcuniversalMediaParentMember | 30,370 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 | 30,975 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest / dei_LegalEntityAxis = cmcsa_NbcuniversalMediaParentMember | 30,370 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest / dei_LegalEntityAxis = cmcsa_NbcuniversalMediaParentMember |  |
Total liabilities and equity | 42,772 us-gaap_LiabilitiesAndStockholdersEquity / dei_LegalEntityAxis = cmcsa_NbcuniversalMediaParentMember | 42,135 us-gaap_LiabilitiesAndStockholdersEquity / dei_LegalEntityAxis = cmcsa_NbcuniversalMediaParentMember |  |
Comcast Non-Guarantor Subsidiaries [Member] |  |  |  |
Cash and cash equivalents | 3,598 us-gaap_CashAndCashEquivalentsAtCarryingValue / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember | 3,525 us-gaap_CashAndCashEquivalentsAtCarryingValue / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember | 2,548 us-gaap_CashAndCashEquivalentsAtCarryingValue / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember | 1,382 us-gaap_CashAndCashEquivalentsAtCarryingValue / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember
Investments [Current] | 158 us-gaap_ShortTermInvestments / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember | 602 us-gaap_ShortTermInvestments / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember |  |
Receivables, net | 6,144 us-gaap_AccountsReceivableNetCurrent / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember | 6,321 us-gaap_AccountsReceivableNetCurrent / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember |  |
Programming rights | 945 cmcsa_ProgrammingRightsCurrent / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember | 839 cmcsa_ProgrammingRightsCurrent / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember |  |
Other current assets | 1,394 us-gaap_OtherAssetsCurrent / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember | 1,551 us-gaap_OtherAssetsCurrent / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember |  |
Total current assets | 12,239 us-gaap_AssetsCurrent / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember | 12,838 us-gaap_AssetsCurrent / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember |  |
Film and television costs | 5,637 cmcsa_FilmAndTelevisionCosts / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember | 5,727 cmcsa_FilmAndTelevisionCosts / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember |  |
Investments | 2,832 us-gaap_LongTermInvestments / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember | 2,721 us-gaap_LongTermInvestments / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember |  |
Investments in and amounts due from subsidiaries eliminated upon consolidation | 101,682 cmcsa_InvestmentsInAndAmountsDueFromSubsidiariesEliminatedUponConsolidation / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember | 98,152 cmcsa_InvestmentsInAndAmountsDueFromSubsidiariesEliminatedUponConsolidation / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember |  |
Property and equipment, net | 30,927 us-gaap_PropertyPlantAndEquipmentNet / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember | 30,754 us-gaap_PropertyPlantAndEquipmentNet / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember |  |
Franchise rights | 59,364 us-gaap_IndefiniteLivedFranchiseRights / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember | 59,364 us-gaap_IndefiniteLivedFranchiseRights / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember |  |
Goodwill | 27,302 us-gaap_Goodwill / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember | 27,316 us-gaap_Goodwill / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember |  |
Other intangible assets, net | 16,842 us-gaap_OtherIntangibleAssetsNet / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember | 16,969 us-gaap_OtherIntangibleAssetsNet / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember |  |
Other noncurrent assets, net | 1,970 us-gaap_OtherAssetsNoncurrent / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember | 1,949 us-gaap_OtherAssetsNoncurrent / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember |  |
Total assets | 258,795 us-gaap_Assets / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember | 255,790 us-gaap_Assets / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember |  |
Accounts payable and accrued expenses related to trade creditors | 6,150 us-gaap_AccountsPayableCurrent / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember | 5,618 us-gaap_AccountsPayableCurrent / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember |  |
Accrued participations and residuals | 1,387 cmcsa_AccruedParticipationsAndResidualsCurrent / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember | 1,347 cmcsa_AccruedParticipationsAndResidualsCurrent / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember |  |
Accrued expenses and other current liabilities [condensed] | 4,190 cmcsa_AccruedExpensesAndOtherCurrentLiabilitiesIncludingDeferredRevenue / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember | 3,767 cmcsa_AccruedExpensesAndOtherCurrentLiabilitiesIncludingDeferredRevenue / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember |  |
Current portion of long-term debt | 740 us-gaap_DebtCurrent / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember | 884 us-gaap_DebtCurrent / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember |  |
Total current liabilities | 12,467 us-gaap_LiabilitiesCurrent / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember | 11,616 us-gaap_LiabilitiesCurrent / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember |  |
Long-term debt, less current portion | 4,394 us-gaap_LongTermDebtAndCapitalLeaseObligations / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember | 4,408 us-gaap_LongTermDebtAndCapitalLeaseObligations / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember |  |
Deferred income taxes | 33,059 us-gaap_DeferredTaxLiabilitiesNoncurrent / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember | 33,127 us-gaap_DeferredTaxLiabilitiesNoncurrent / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember |  |
Other noncurrent liabilities | 7,483 us-gaap_OtherLiabilitiesNoncurrent / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember | 7,484 us-gaap_OtherLiabilitiesNoncurrent / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember |  |
Redeemable noncontrolling interests and redeemable subsidiary preferred stock | 1,099 cmcsa_RedeemableNoncontrollingInterestsAndRedeemableSubsidiaryPreferredStock / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember | 1,066 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 | 199,953 cmcsa_OtherStockholdersEquity / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember | 197,732 cmcsa_OtherStockholdersEquity / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember |  |
Total Comcast Corporation shareholders' equity | 199,953 us-gaap_StockholdersEquity / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember | 197,732 us-gaap_StockholdersEquity / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember |  |
Noncontrolling interests | 340 us-gaap_MinorityInterest / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember | 357 us-gaap_MinorityInterest / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember |  |
Total equity | 200,293 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember | 198,089 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember |  |
Total liabilities and equity | 258,795 us-gaap_LiabilitiesAndStockholdersEquity / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember | 255,790 us-gaap_LiabilitiesAndStockholdersEquity / dei_LegalEntityAxis = cmcsa_ComcastNonGuarantorSubsidiariesMember |  |
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 | (504,567)cmcsa_InvestmentsInAndAmountsDueFromSubsidiariesEliminatedUponConsolidation / us-gaap_ConsolidationItemsAxis = cmcsa_EliminationAndConsolidationAdjustmentsMember | (495,953)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 | (1,097)us-gaap_OtherAssetsNoncurrent / us-gaap_ConsolidationItemsAxis = cmcsa_EliminationAndConsolidationAdjustmentsMember | (1,080)us-gaap_OtherAssetsNoncurrent / us-gaap_ConsolidationItemsAxis = cmcsa_EliminationAndConsolidationAdjustmentsMember |  |
Total assets | (505,664)us-gaap_Assets / us-gaap_ConsolidationItemsAxis = cmcsa_EliminationAndConsolidationAdjustmentsMember | (497,033)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 | (953)us-gaap_DeferredTaxLiabilitiesNoncurrent / us-gaap_ConsolidationItemsAxis = cmcsa_EliminationAndConsolidationAdjustmentsMember | (936)us-gaap_DeferredTaxLiabilitiesNoncurrent / us-gaap_ConsolidationItemsAxis = cmcsa_EliminationAndConsolidationAdjustmentsMember |  |
Other noncurrent liabilities | (144)us-gaap_OtherLiabilitiesNoncurrent / us-gaap_ConsolidationItemsAxis = cmcsa_EliminationAndConsolidationAdjustmentsMember | (144)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 | (504,567)cmcsa_OtherStockholdersEquity / us-gaap_ConsolidationItemsAxis = cmcsa_EliminationAndConsolidationAdjustmentsMember | (495,953)cmcsa_OtherStockholdersEquity / us-gaap_ConsolidationItemsAxis = cmcsa_EliminationAndConsolidationAdjustmentsMember |  |
Total Comcast Corporation shareholders' equity | (504,567)us-gaap_StockholdersEquity / us-gaap_ConsolidationItemsAxis = cmcsa_EliminationAndConsolidationAdjustmentsMember | (495,953)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 | (504,567)us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest / us-gaap_ConsolidationItemsAxis = cmcsa_EliminationAndConsolidationAdjustmentsMember | (495,953)us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest / us-gaap_ConsolidationItemsAxis = cmcsa_EliminationAndConsolidationAdjustmentsMember |  |
Total liabilities and equity | $ (505,664)us-gaap_LiabilitiesAndStockholdersEquity / us-gaap_ConsolidationItemsAxis = cmcsa_EliminationAndConsolidationAdjustmentsMember | $ (497,033)us-gaap_LiabilitiesAndStockholdersEquity / us-gaap_ConsolidationItemsAxis = cmcsa_EliminationAndConsolidationAdjustmentsMember |  |

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- Definition The total amount of participations, residual and royalty expenses due to another party in less than one year. Royalty expenses are due to content creators, including artists, authors and other talent; participations includes amounts to financial participants in films, including actors, directors, and producers, for contractually defined participations in a film's net profit or gross receipts; residuals include amounts due to unions and guilds. + References No definition available. + Details
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