Related Party Transactions - Condensed Consolidated Statement of Income (Details) - USD ($) $ in Millions |
3 Months Ended | 9 Months Ended | ||
|---|---|---|---|---|
Sep. 30, 2015 |
Sep. 30, 2014 |
Sep. 30, 2015 |
Sep. 30, 2014 |
|
| Revenue | $ 18,669 | $ 16,791 | $ 55,265 | $ 51,043 |
| NBCUniversal Media, LLC [Member] | ||||
| Revenue | 7,151 | 5,921 | 20,985 | 18,813 |
| Transactions With Comcast And Consolidated Subsidiaries [Member] | NBCUniversal Media, LLC [Member] | ||||
| Revenue | 334 | 316 | 1,006 | 989 |
| Operating costs and expenses | (71) | (32) | (164) | (96) |
| Other income (expense) | $ (7) | $ (10) | $ (25) | $ (32) |