Leases - Lease Costs (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Lessee, Lease, Description [Line Items]
Operating lease cost	$ 111	$ 125
Short-term lease cost	31	35
Other	8	0
Total lease cost	150	$ 160
Agreement to store at facilities owned by equity method investee | Equity Method Investees
Lessee, Lease, Description [Line Items]
Other	$ 6
Ownership interest in unconsolidated entity	50.00%