Related Party Transactions - Schedule of Other Related Party Balances (Details) - USD ($) $ in Millions	Mar. 31, 2021	Dec. 31, 2020
Related Party Transaction [Line Items]
Accounts receivable	$ 31	$ 21
Prepaid expenses	14	22
Other assets	2	2
Contract assets	229	233
Accounts payable	12	16
Deferred revenue	22	19
Accrued liabilities	16	28
Debt payable	2,691	2,692
Finance lease liability	2	2
Financing receivables	297	298
Accrued interest, related parties	12	16
Other accrued liabilities, related parties	4	12
Unamortized debt issuance costs	3	2
Affiliated Entity
Related Party Transaction [Line Items]
Unamortized debt issuance costs	$ 3	$ 2

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