Commitments and Contingencies - Lease Commitments (Details) $ in Millions	Dec. 31, 2018 USD ($)
Operating Leases
2019	$ 32
2020	30
2021	24
2022	16
2023 and thereafter	46
Total minimum lease payments	148
Less: Amounts representing interest	0
Present value of minimum lease payments	148
Capital Leases
2019	2
2020	0
2021	0
2022	0
2023 and thereafter	0
Total minimum lease payments	2
Less: Amounts representing interest	0
Present value of minimum lease payments	$ 2

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