v3.3.0.814
Supplemental Financial Information (Components of Accumulated Other Comprehensive Income (Loss)) (Details) - USD ($)
$ in Millions
Sep. 30, 2015
Dec. 31, 2014
Sep. 30, 2014
Unrealized gains (losses) on marketable securities $ 1   $ 3
Deferred gains (losses) on cash flow hedges (29)   (29)
Unrecognized gains (losses) on employee benefit obligations (54)   70
Cumulative translation adjustments (113)   (41)
Accumulated other comprehensive income (loss), net of deferred taxes (195) $ (146) 3
NBCUniversal Media, LLC [Member]      
Unrealized gains (losses) on marketable securities 0   3
Deferred gains (losses) on cash flow hedges 8   4
Unrecognized gains (losses) on employee benefit obligations (39)   45
Cumulative translation adjustments (180)   (64)
Accumulated other comprehensive income (loss), net of deferred taxes $ (211) $ (159) $ (12)