Schedule of Valuation and Qualifying Accounts Disclosure (Details) - USD ($) $ in Millions |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2015 |
Dec. 31, 2014 |
Dec. 31, 2013 |
|
| Allowance for Doubtful Accounts [Member] | |||
| Movement in Valuation Allowances and Reserves [Roll Forward] | |||
| Balance at Beginning of Year | $ 4 | $ 5 | $ 6 |
| Charged to Expense | (2) | (1) | 4 |
| Charged to Other Accounts | 0 | 0 | (5) |
| Deductions | 0 | 0 | 0 |
| Balance at End of Year | 2 | 4 | 5 |
| Deferred Tax Asset Valuation Allowance [Member] | |||
| Movement in Valuation Allowances and Reserves [Roll Forward] | |||
| Balance at Beginning of Year | 1,836 | 2,246 | 2,222 |
| Charged to Expense | (199) | (410) | 24 |
| Charged to Other Accounts | 0 | 0 | 0 |
| Deductions | 0 | 0 | 0 |
| Balance at End of Year | $ 1,637 | $ 1,836 | $ 2,246 |