v3.7.0.1

Investments (Schedule of Investments) (Details) - USD ($) $ in Millions | Mar. 31, 2017 | Dec. 31, 2016
--- | --- | ---
Fair Value, Equity And Cost Method Investments [Line Items] |  |
Fair value method | $ 823 | $ 198
Equity method | 2,426 | 2,376
Cost method | 2,700 | 2,770
Total Investments | 5,949 | 5,344
Less: Current investments | 11 | 97
Noncurrent Investments | 5,938 | 5,247
Snap [Member] |  |
Fair Value, Equity And Cost Method Investments [Line Items] |  |
Fair value method | 662 | 0
Other Fair Value Method Investments [Member] |  |
Fair Value, Equity And Cost Method Investments [Line Items] |  |
Fair value method | 161 | 198
Atairos [Member] |  |
Fair Value, Equity And Cost Method Investments [Line Items] |  |
Equity method | 1,624 | 1,601
Hulu [Member] |  |
Fair Value, Equity And Cost Method Investments [Line Items] |  |
Equity method | 171 | 225
Other Equity Method Investments [Member] |  |
Fair Value, Equity And Cost Method Investments [Line Items] |  |
Equity method | 631 | 550
AirTouch [Member] |  |
Fair Value, Equity And Cost Method Investments [Line Items] |  |
Cost method | 1,602 | 1,599
BuzzFeed [Member] |  |
Fair Value, Equity And Cost Method Investments [Line Items] |  |
Cost method | 400 | 400
Other Cost Method Investments [Member] |  |
Fair Value, Equity And Cost Method Investments [Line Items] |  |
Cost method | 698 | 771
NBCUniversal Media LLC [Member] |  |
Fair Value, Equity And Cost Method Investments [Line Items] |  |
Fair value method | 669 | 6
Equity method | 571 | 561
Cost method | 700 | 696
Total Investments | 1,940 | 1,263
Noncurrent Investments | 1,940 | 1,263
NBCUniversal Media LLC [Member] | Snap [Member] |  |
Fair Value, Equity And Cost Method Investments [Line Items] |  |
Fair value method | 662 | 0
NBCUniversal Media LLC [Member] | Other Fair Value Method Investments [Member] |  |
Fair Value, Equity And Cost Method Investments [Line Items] |  |
Fair value method | 7 | 6
NBCUniversal Media LLC [Member] | Hulu [Member] |  |
Fair Value, Equity And Cost Method Investments [Line Items] |  |
Equity method | 171 | 225
NBCUniversal Media LLC [Member] | Other Equity Method Investments [Member] |  |
Fair Value, Equity And Cost Method Investments [Line Items] |  |
Equity method | 400 | 336
NBCUniversal Media LLC [Member] | BuzzFeed [Member] |  |
Fair Value, Equity And Cost Method Investments [Line Items] |  |
Cost method | 400 | 400
NBCUniversal Media LLC [Member] | Other Cost Method Investments [Member] |  |
Fair Value, Equity And Cost Method Investments [Line Items] |  |
Cost method | $ 300 | $ 296

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