v3.3.1.900
Pension Plans and Postretirement Benefits (Information On Our Pension Benefit Plans) (Details) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2015
Dec. 31, 2014
Dec. 31, 2013
Pension Benefits [Member]      
Benefit obligation $ 309 $ 581 $ 498
Fair value of plan assets 0 242 220
Plan funded status and recorded benefit obligation (309) (339) (278)
Portion of benefit obligation not yet recognized in benefits expense 14 53 (3)
Benefits expense 13 $ 14 $ 12
Expected return on plan assets   5.00% 5.00%
Pension Benefits [Member] | NBCUniversal Media LLC [Member]      
Benefit obligation 309 $ 581 $ 498
Fair value of plan assets 0 242 220
Plan funded status and recorded benefit obligation (309) (339) (278)
Portion of benefit obligation not yet recognized in benefits expense 14 53 (3)
Benefits expense $ 13 $ 14 $ 12
Expected return on plan assets   5.00% 5.00%
Pension Benefits [Member] | Minimum [Member]      
Discount rate 4.31% 3.75% 4.50%
Pension Benefits [Member] | Minimum [Member] | NBCUniversal Media LLC [Member]      
Discount rate 4.31% 3.75% 4.50%
Pension Benefits [Member] | Maximum [Member]      
Discount rate 4.40% 4.25% 5.25%
Pension Benefits [Member] | Maximum [Member] | NBCUniversal Media LLC [Member]      
Discount rate 4.40% 4.25% 5.25%
Postretirement Benefits [Member]      
Benefit obligation $ 820 $ 837 $ 633
Plan funded status and recorded benefit obligation (820) (837) (633)
Portion of benefit obligation not yet recognized in benefits expense (33) 46 (110)
Benefits expense 75 $ 59 65
Discount rate   4.25%  
Postretirement Benefits [Member] | NBCUniversal Media LLC [Member]      
Benefit obligation 197 $ 209 158
Plan funded status and recorded benefit obligation (197) (209) (158)
Portion of benefit obligation not yet recognized in benefits expense (27) (3) (44)
Benefits expense $ 15 $ 12 $ 14
Discount rate 4.73% 4.25% 5.25%
Postretirement Benefits [Member] | Minimum [Member]      
Discount rate 4.70%   5.00%
Postretirement Benefits [Member] | Maximum [Member]      
Discount rate 4.73%   5.25%