Related Party Transactions - Related Party Receivable and Payable (Details) - USD ($) $ in Millions |
Sep. 30, 2019 |
Dec. 31, 2018 |
|---|---|---|
| Related Party Transaction [Line Items] | ||
| Due from related parties | $ 11 | $ 7 |
| Due to related parties | 135 | 139 |
| Other current assets | ||
| Related Party Transaction [Line Items] | ||
| Due from related parties | 11 | 7 |
| Other current liabilities | ||
| Related Party Transaction [Line Items] | ||
| Due to related parties | 13 | 9 |
| Contingent liabilities, current | ||
| Related Party Transaction [Line Items] | ||
| Due to related parties | 122 | 25 |
| Contingent liabilities | ||
| Related Party Transaction [Line Items] | ||
| Due to related parties | $ 0 | $ 105 |