Share-Based Compensation (Recognized Share-Based Compensation Expense) (Details) - USD ($) $ in Millions |
3 Months Ended | |
|---|---|---|
Mar. 31, 2016 |
Mar. 31, 2015 |
|
| Recognized share-based compensation expense | $ 115 | $ 101 |
| NBCUniversal Media LLC [Member] | ||
| Recognized share-based compensation expense | 23 | 21 |
| Restricted Share Units [Member] | ||
| Recognized share-based compensation expense | 70 | 58 |
| Restricted Share Units [Member] | NBCUniversal Media LLC [Member] | ||
| Recognized share-based compensation expense | 18 | 17 |
| Stock Options [Member] | ||
| Recognized share-based compensation expense | 37 | 35 |
| Stock Options [Member] | NBCUniversal Media LLC [Member] | ||
| Recognized share-based compensation expense | 2 | 2 |
| Employee Stock Purchase Plan [Member] | ||
| Recognized share-based compensation expense | 8 | 8 |
| Employee Stock Purchase Plan [Member] | NBCUniversal Media LLC [Member] | ||
| Recognized share-based compensation expense | $ 3 | $ 2 |