Related Party Transactions - Schedule of Other Related Party Balances (Details) - USD ($) $ in Millions	Jun. 30, 2019	Dec. 31, 2018
Related Party Transaction [Line Items]
Accounts receivable	$ 39	$ 29
Prepaid expenses	6	15
Other assets	2	3
Accounts payable	8	9
Deferred revenue	0	3
Accrued liabilities	17	16
Debt payable	2,691	2,091
Accrued interest, related parties	16	14
Other accrued liabilities, related parties	1	2
Unamortized debt issuance costs	3	3
Affiliated Entity
Related Party Transaction [Line Items]
Unamortized debt issuance costs	$ 3	$ 3

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