Leases - Components of Lease Expense (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2020	Dec. 31, 2019
Lease Cost [Abstract]
Operating lease cost	[1]	$ 28	$ 24
Finance lease cost:
Amortization of right-of-use assets	[2]	10	9
Interest on lease liabilities	[3]	4	4
Total finance lease cost		14	13
Sublease income on operating leases	[1]	(3)	(3)
Total lease cost, net		$ 39	$ 34

[1] Operating lease costs, net of sublease income, are included within operating expenses in our consolidated statements of operations.

[2] Amount is included in depreciation expense in our consolidated statements of operations.

[3] Amount is included in interest expense in our consolidated statements of operations.