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Related Party Transactions - Consolidated Balance Sheet (Details) (USD $)
In Millions, unless otherwise specified |
Dec. 31, 2014
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Dec. 31, 2013
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|---|---|---|
| Receivables, net | $ 6,321us-gaap_AccountsReceivableNetCurrent | $ 6,376us-gaap_AccountsReceivableNetCurrent |
| Accounts payable and accrued expenses related to trade creditors | 5,638us-gaap_AccountsPayableCurrent | 5,528us-gaap_AccountsPayableCurrent |
| Accrued expenses and other current liabilities | 5,293us-gaap_AccruedLiabilitiesCurrent | 7,967us-gaap_AccruedLiabilitiesCurrent |
| Other noncurrent liabilities | 10,819us-gaap_OtherLiabilitiesNoncurrent | 11,384us-gaap_OtherLiabilitiesNoncurrent |
| NBCUniversal Media, LLC [Member] | ||
| Receivables, net | 4,842us-gaap_AccountsReceivableNetCurrent / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember |
4,911us-gaap_AccountsReceivableNetCurrent / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember |
| Accounts payable and accrued expenses related to trade creditors | 1,388us-gaap_AccountsPayableCurrent / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember |
1,583us-gaap_AccountsPayableCurrent / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember |
| Accrued expenses and other current liabilities | 1,422us-gaap_AccruedLiabilitiesCurrent / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember |
1,465us-gaap_AccruedLiabilitiesCurrent / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember |
| Note payable to Comcast | 865cmcsa_NotesPayableToComcast / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember |
799cmcsa_NotesPayableToComcast / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember |
| Other noncurrent liabilities | 3,722us-gaap_OtherLiabilitiesNoncurrent / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember |
3,412us-gaap_OtherLiabilitiesNoncurrent / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember |
| Transactions With Comcast And Consolidated Subsidiaries [Member] | NBCUniversal Media, LLC [Member] | ||
| Receivables, net | 229us-gaap_AccountsReceivableNetCurrent / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_RelatedPartyTransactionsByRelatedPartyAxis = cmcsa_ComcastAndConsolidatedSubsidiariesMember |
228us-gaap_AccountsReceivableNetCurrent / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_RelatedPartyTransactionsByRelatedPartyAxis = cmcsa_ComcastAndConsolidatedSubsidiariesMember |
| Accounts payable and accrued expenses related to trade creditors | 47us-gaap_AccountsPayableCurrent / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_RelatedPartyTransactionsByRelatedPartyAxis = cmcsa_ComcastAndConsolidatedSubsidiariesMember |
56us-gaap_AccountsPayableCurrent / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_RelatedPartyTransactionsByRelatedPartyAxis = cmcsa_ComcastAndConsolidatedSubsidiariesMember |
| Accrued expenses and other current liabilities | 8us-gaap_AccruedLiabilitiesCurrent / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_RelatedPartyTransactionsByRelatedPartyAxis = cmcsa_ComcastAndConsolidatedSubsidiariesMember |
37us-gaap_AccruedLiabilitiesCurrent / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_RelatedPartyTransactionsByRelatedPartyAxis = cmcsa_ComcastAndConsolidatedSubsidiariesMember |
| Note payable to Comcast | 865cmcsa_NotesPayableToComcast / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_RelatedPartyTransactionsByRelatedPartyAxis = cmcsa_ComcastAndConsolidatedSubsidiariesMember |
799cmcsa_NotesPayableToComcast / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_RelatedPartyTransactionsByRelatedPartyAxis = cmcsa_ComcastAndConsolidatedSubsidiariesMember |
| Other noncurrent liabilities | $ 383us-gaap_OtherLiabilitiesNoncurrent / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_RelatedPartyTransactionsByRelatedPartyAxis = cmcsa_ComcastAndConsolidatedSubsidiariesMember |
$ 383us-gaap_OtherLiabilitiesNoncurrent / dei_LegalEntityAxis = cmcsa_NBCUniversalMediaLLCMember / us-gaap_RelatedPartyTransactionsByRelatedPartyAxis = cmcsa_ComcastAndConsolidatedSubsidiariesMember |
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- Definition
The total amount due to Comcast, with respect to cash management arrangements under the matching revolving credit notes, as of the balance sheet date. No definition available.
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- Definition
Carrying value as of the balance sheet date of liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer). Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Amount due from customers or clients, within one year of the balance sheet date (or the normal operating cycle, whichever is longer), for goods or services (including trade receivables) that have been delivered or sold in the normal course of business, reduced to the estimated net realizable fair value by an allowance established by the entity of the amount it deems uncertain of collection. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Carrying value as of the balance sheet date of obligations incurred and payable, pertaining to costs that are statutory in nature, are incurred on contractual obligations, or accumulate over time and for which invoices have not yet been received or will not be rendered. Examples include taxes, interest, rent and utilities. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer). Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Aggregate carrying amount, as of the balance sheet date, of noncurrent obligations not separately disclosed in the balance sheet. Noncurrent liabilities are expected to be paid after one year (or the normal operating cycle, if longer). Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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- Details
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