Leases - Maturities of Lease Liabilities (Details) $ in Millions	12 Months Ended
	Dec. 31, 2019 USD ($)
Operating leases
2020	$ 119
2021	104
2022	59
2023	38
2024	22
Thereafter	58
Total lease payments	400
Less: Interest	40
Present value of lease liabilities	360
Finance leases
2020	10
2021	9
2022	8
2023	1
2024	0
Thereafter	0
Total lease payments	28
Less: Interest	1
Present value of lease liabilities	27
Total
2020	129	[1],[2]
2021	113	[1],[2]
2022	67	[1],[2]
2023	39	[1],[2]
2024	22	[1],[2]
Thereafter	58	[1],[2]
Total lease payments	428	[1],[2]
Less: Interest	41	[1],[2]
Present value of lease liabilities	387	[1],[2]
Contractual minimum lease payments for leases executed but not yet commenced	$ 350
Lease term for leases executed but not yet commenced	11 years

[1] Lease payments recognized as part of lease liabilities for optional renewal periods are insignificant.

[2] Total lease payments exclude approximately $350 million of contractual minimum lease payments for leases executed but not yet commenced. These leases will commence in 2020 with lease terms of approximately 11 years.