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Supplemental Financial Information (Noncash Investing and Financing Activities)(Details) (USD $)
In Millions, except Per Share data, unless otherwise specified |
3 Months Ended |
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Mar. 31, 2015
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| Dividends payable, amount | $ 630us-gaap_DividendsPayableCurrentAndNoncurrent |
| Dividends payable, amount per share | $ 0.25us-gaap_DividendsPayableAmountPerShare |
| Capital expenditures incurred but not yet paid | 978us-gaap_CapitalExpendituresIncurredButNotYetPaid |
| Fair Value Equity Securities Settlement | 517cmcsa_FairValueEquitySecuritiesSettlement |
| Capital contribution accrued but not yet paid | 123cmcsa_CapitalContributionAccruedButNotYetPaid |
| NBCUniversal Media, LLC [Member] | |
| Capital expenditures incurred but not yet paid | 153us-gaap_CapitalExpendituresIncurredButNotYetPaid / cmcsa_LegalEntity1Axis = cmcsa_NBCUniversalMediaLLCMember |
| Capital contribution accrued but not yet paid | $ 123cmcsa_CapitalContributionAccruedButNotYetPaid / cmcsa_LegalEntity1Axis = cmcsa_NBCUniversalMediaLLCMember |
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- Definition
The carrying value of a liability for a capital contribution for an investment that was accrued but not yet paid No definition available.
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- Definition
Fair value method equity securities used to settle our obligations under prepaid forward sale agreements in the period. No definition available.
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- Definition
Future cash outflow to pay for purchases of fixed assets that have occurred. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
The per share amount of a dividend declared, but not paid, as of the financial reporting date. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Carrying value as of the balance sheet date of dividends declared but unpaid on equity securities issued by the entity and outstanding. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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