v2.4.0.8

Condensed Consolidating Financial Information (Narrative) (Details) (USD $) | Sep. 30, 2014
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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
NBCUniversal Enterprise Credit Facility [Member] |
Credit facility borrowing capacity | 1,350,000,000
NBCUniversal Enterprise [Member] |
Principal amount of debt securities subject to guarantee | $ 4,000,000,000

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