Related Party Transactions - Schedule of Other Related Party Balances (Details) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Related Party Transaction [Line Items]
Accounts receivable	$ 29	$ 29
Prepaid expenses	11	15
Other assets	3	3
Accounts payable	9	9
Deferred revenue	1	3
Accrued liabilities	15	16
Debt payable	2,091	2,091
Accrued interest, related parties	14	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

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