Leases - Lease Expense (Details) $ in Millions	12 Months Ended
	Dec. 31, 2019 USD ($)
Leases [Abstract]
Operating and short-term lease cost	$ 43
Lease, Cost [Abstract]
Amortization of right-of-use assets	9
Interest on lease liability	1
Total finance lease cost	10
Total lease cost	$ 53