Leases - Maturities (Details) $ in Millions	Dec. 31, 2021 USD ($)
Maturities of operating lease liabilities
2022	$ 190
2023	151
2024	79
2025	52
2026	47
Thereafter	84
Total undiscounted lease payments	603
Less imputed interest	(72)
Total operating lease liability	531
Maturities of finance lease liabilities
2022	27
2023	27
2024	25
2025	17
2026	12
Thereafter	43
Total undiscounted lease payments	151
Less imputed interest	(24)
Total finance lease liability	$ 127
Weighted average discount rate for operating leases	5.37%
Weighted average discount rate for financing leases	4.16%