Leases - Maturities (Details) $ in Millions	Sep. 30, 2019 USD ($)
Leases [Abstract]
Operating Leases, Remainder of 2019	$ 13
Operating Leases, 2020	47
Operating Leases, 2021	39
Operating Leases, 2022	29
Operating Leases, 2023	22
Operating Leases, Thereafter	58
Operating Leases, Total lease payments	208
Operating Leases, Less: interest	31
Operating Leases, Present value of lease liabilities	177
Finance Leases, Remainder of 2019	1
Finance Leases, 2020	6
Finance Leases, 2021	6
Finance Leases, 2022	5
Finance Leases, 2023	3
Finance Leases, Thereafter	14
Finance Leases, Total lease payments	35
Finance Leases, Less: interest	5
Finance Leases, Present value of lease liabilities	$ 30