v2.4.0.8
Condensed Consolidating Financial Information (Narrative) (Details) (USD $)
12 Months Ended
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