Leasing - Present Value of Lease Liabilities (Details) $ in Millions	Mar. 31, 2020 USD ($)
Operating Leases
Remainder of 2020	$ 88
2021	86
2022	64
2023	44
2024	38
Thereafter	272
Total lease payments	592
Less: Amount representing interest	(158)
Present value of lease liabilities	434
Finance Leases
Remainder of 2020	10
2021	14
2022	13
2023	6
2024	0
Thereafter	0
Total lease payments	43
Less: Amount representing interest	(2)
Present value of lease liabilities	$ 41