Leases - Lease Maturities (Details) $ in Millions	Dec. 31, 2019 USD ($)
Operating Leases
2020	$ 28
2021	20
2022	14
2023	10
2024	5
Thereafter	3
Subtotal - undiscounted lease payments	80
Less imputed interest	(7)
Total operating lease liabilities	73
Finance Leases
2020	23
2021	24
2022	21
2023	21
2024	22
Thereafter	289
Subtotal - undiscounted lease payments	400
Less imputed interest	(161)
Total finance lease liabilities	$ 239