Pension Plans and Postretirement Benefits (Deferred Compensation Plans) (Details) - Deferred Compensation Plans [Member] - USD ($) $ in Millions |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2015 |
Dec. 31, 2014 |
Dec. 31, 2013 |
|
| Benefit obligation | $ 2,038 | $ 1,774 | $ 1,434 |
| Interest expense | 171 | 149 | 128 |
| NBCUniversal Media LLC [Member] | |||
| Benefit obligation | 417 | 349 | 250 |
| Interest expense | $ 28 | $ 24 | $ 18 |