v2.4.0.8

Condensed Consolidating Financial Information (Narrative) (Details) (USD $) | 12 Months Ended
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Dec. 31, 2013
Holding company ownership in subsidiaries | 100.00%
Comcast Holdings' ZONES due October 2029 [Member] |
Principal amount of debt securities subject to guarantee | $ 185,000,000
Comcast Holdings' ZONES due November 2029 [Member] |
Principal amount of debt securities not subject to guarantee | 62,000,000
Guarantor Subsidiaries [Member] |
Principal amount of debt securities subject to guarantee | 30,900,000,000
Maturing In Next Five Years [Member] |
Principal amount of debt securities subject to guarantee | 11,000,000,000
Comcast And Comcast Cable Communications LLC [Member] |
Credit facility borrowing capacity | 6,250,000,000
NBCUniversal Enterprise [Member] |
Credit facility borrowing capacity | 1,350,000,000
Principal amount of debt securities subject to guarantee | $ 4,000,000,000

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