Supplemental Financial Information (Cash Payments for Interest and Income Taxes)(Details) - USD ($) $ in Millions |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2016 |
Dec. 31, 2015 |
Dec. 31, 2014 |
|
| Cash Payments for Interest and Income Taxes | |||
| Interest | $ 2,565 | $ 2,443 | $ 2,389 |
| Income taxes | 3,693 | 3,726 | 3,668 |
| NBCUniversal Media LLC [Member] | |||
| Cash Payments for Interest and Income Taxes | |||
| Interest | 548 | 456 | 485 |
| Income taxes | $ 208 | $ 182 | $ 174 |