Leases - Schedule of Lease Obligations (Details) - USD ($) $ in Millions	Jun. 30, 2019	Jan. 01, 2019	Dec. 31, 2018
Operating Leases
Other current liabilities	$ 17	$ 16
Operating lease liabilities - non-current	75	$ 57
Total lease liabilities	93
Finance Leases
Other current liabilities	1
Finance lease non-current liabilities	33		$ 1
Total lease liabilities	46
Operating Leases, Liability, Related Party	1
Finance Leases, Liability, Related Party	$ 12