| **Fair Value Measurements (Details) - USD ($) $ in Millions** | Sep. 30, 2016 | Dec. 31, 2015 |
|---------------------------------------------------------------|---------------|---------------|
| Level 1                                                       |          |          |
| **Assets**                                                    |          |          |
| Investment in equity securities                               | $ 2           | $ 0           |
| Recurring basis | Level 1                                     |          |          |
| **Assets**                                                    |          |          |
| Investment in equity securities                               | 2             |          |
| Recurring basis | Level 2                                     |          |          |
| **Assets**                                                    |          |          |
| Derivative financial instruments, net                         | $ 17          | $ 81          |

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| - Definition
Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.
+ References
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| - Definition
Fair values as of the balance sheet date of the net amount of all assets and liabilities resulting from contracts that meet the criteria of being accounted for as derivative instruments.
+ References
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