Derivative Financial Instruments - Cumulative Basis Adjustments for Fair Value Hedges (Details) - USD ($) $ in Millions |
Mar. 31, 2020 |
Dec. 31, 2019 |
|---|---|---|
| Short-term debt | ||
| Amounts recorded in the Consolidated Statement of Financial Position related to cumulative basis adjustments for fair value hedges | ||
| Carrying amount of the hedged item | $ (1,314) | |
| Cumulative hedging adjustments included in the carrying amount-assets/(liabilities) | (15) | |
| Long-term debt | ||
| Amounts recorded in the Consolidated Statement of Financial Position related to cumulative basis adjustments for fair value hedges | ||
| Carrying amount of the hedged item | (2,147) | $ (3,411) |
| Cumulative hedging adjustments included in the carrying amount-assets/(liabilities) | (475) | (440) |
| Hedging adjustments on discontinued hedging relationships | $ (391) | $ (404) |