Derivative and Financial Instruments - FX Balance Sheet (Details) - USD ($) $ in Millions |
Dec. 31, 2019 |
Dec. 31, 2018 |
|---|---|---|
| Prepaid expenses and other current assets [Member] | ||
| Derivatives, Fair Value [Line Items] | ||
| Foreign currency exchange derivative assets | $ 1 | $ 7 |
| Other accruals [Member] | ||
| Derivatives, Fair Value [Line Items] | ||
| Foreign currency exchange derivative liabilities | 20 | 6 |
| Other liabilities and deferred credits [Member] | ||
| Derivatives, Fair Value [Line Items] | ||
| Foreign currency exchange derivative liabilities | $ 8 | $ 0 |