Derivatives and Risk Management - Balance Sheet Location of Hedged Item (Details) - USD ($) $ in Millions |
Sep. 30, 2020 |
Dec. 31, 2019 |
|---|---|---|
| Derivative [Line Items] | ||
| Cumulative amount of adjustments remaining for which hedge accounting has been discontinued | $ 84 | |
| Current maturities of debt and finance leases | ||
| Derivative [Line Items] | ||
| Carrying amount of hedge instruments | 21 | $ (19) |
| Cumulative amount of fair value hedge adjustments | 21 | 8 |
| Debt and finance leases | ||
| Derivative [Line Items] | ||
| Carrying amount of hedge instruments | (61) | (1,783) |
| Cumulative amount of fair value hedge adjustments | $ 88 | $ 53 |