Acquisitions and Dispositions Additional Information (Details) - USD ($) $ in Millions |
3 Months Ended | |
|---|---|---|
Jun. 30, 2016 |
Mar. 31, 2016 |
|
| Business Acquisition [Line Items] | ||
| Equity Method Investments | $ 20 | |
| Subsequent Event [Member] | ||
| Business Acquisition [Line Items] | ||
| Proceeds from Sale of Other Investments | $ 41 | |
| Subsequent Event [Member] | Minimum [Member] | ||
| Business Acquisition [Line Items] | ||
| Gain (Loss) on Sale of Other Investments | 18 | |
| Subsequent Event [Member] | Maximum [Member] | ||
| Business Acquisition [Line Items] | ||
| Gain (Loss) on Sale of Other Investments | $ 23 |