Assets and Liabilities Measured at Fair Value - Assets And Liabilities Measured At Fair Value On A Recurring Basis (Details) - USD ($) $ in Millions |
Sep. 30, 2020 |
Dec. 31, 2019 |
|---|---|---|
| Recurring | ||
| Assets and liabilities measured at fair value | ||
| Cash equivalents | $ 524 | $ 339 |
| Indemnification asset | 310 | 202 |
| Debt | 1,682 | 1,557 |
| Recurring | Level 1 | ||
| Assets and liabilities measured at fair value | ||
| Cash equivalents | 524 | 339 |
| Recurring | Level 2 | ||
| Assets and liabilities measured at fair value | ||
| Indemnification asset | 310 | 202 |
| Debt | $ 1,682 | $ 1,557 |
| 1.75% Exchangeable Senior Debentures due 2046 | ||
| Assets and liabilities measured at fair value | ||
| Interest rate (as a percent) | 1.75% |