Leases - Schedule of Future Minimum Operating and Finance Lease Payments (Details) $ in Millions	Sep. 30, 2019 USD ($)
Operating Leases
2019 (excluding the nine months ended September 30, 2019)	$ 6
2020	21
2021	16
2022	14
2023	13
Thereafter	49
Total lease payments	119
Less imputed interest	20
Total lease liabilities	99
Finance Leases
2019 (excluding the nine months ended September 30, 2019)	1
2020	4
2021	15
2022	3
2023	3
Thereafter	37
Total lease payments	63
Less imputed interest	17
Total lease liabilities	$ 46