Leases - Maturity Schedules (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Operating leases
2021	$ 106
2022	81
2023	60
2024	39
2025	26
Thereafter	60
Total future undiscounted lease payments	372
Less imputed interest	(36)
Total reported lease liability	336	$ 330
Finance leases
2021	3
2022	2
2023	2
2024	1
2025	0
Thereafter	0
Total future undiscounted lease payments	8
Less imputed interest	0
Total reported lease liability	$ 8	$ 2