Financial Instruments - Reconciliation of recurring Level 3 fair value measurements (Details) - USD ($) $ in Millions |
12 Months Ended | |
|---|---|---|
Dec. 31, 2022 |
Dec. 31, 2021 |
|
| Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] | ||
| Balance at beginning of year | $ 8 | $ 30 |
| Proceeds at maturity | (8) | (22) |
| Balance at end of year | $ 0 | $ 8 |