v3.7.0.1

Investments (Equity Method Investments) (Details) - USD ($) $ in Millions | 1 Months Ended | 3 Months Ended
--- | --- | ---
Jan. 31, 2016 | Mar. 31, 2017 | Mar. 31, 2016
Schedule of Equity Method Investments [Line Items] |  |  |
Equity in net income (losses) of investees |  | $ 36 | $ (11)
Atairos [Member] |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |
Purchases of investments |  | 457 |
Equity in net income (losses) of investees |  | 57 | (15)
The Weather Channel [Member] |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |
Pretax gain on sale of investment | $ 108 |  |
NBCUniversal Media LLC [Member] |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |
Equity in net income (losses) of investees |  | $ (26) | $ (2)
NBCUniversal Media LLC [Member] | The Weather Channel [Member] |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |
Pretax gain on sale of investment | $ 108 |  |

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