Derivatives and Risk Management - Balance Sheet Location of Hedged Item (Details) - USD ($) $ in Millions |
Dec. 31, 2019 |
Dec. 31, 2018 |
|---|---|---|
| Current maturities of debt and finance leases | ||
| Derivative [Line Items] | ||
| Carrying amount of hedged instruments | $ (19) | $ (11) |
| Cumulative amount of fair value hedge adjustments | 8 | 7 |
| Debt and finance leases | ||
| Derivative [Line Items] | ||
| Carrying amount of hedged instruments | (1,783) | (1,870) |
| Cumulative amount of fair value hedge adjustments | $ 53 | $ (8) |