Relationship with Former Parent and Related Entities - Summary of Amount Due to and from Related Parties (Details) - USD ($) $ in Millions	Sep. 30, 2018	Dec. 31, 2017
Related Party Transactions [Abstract]
Related party receivable	$ 63	$ 0
Related party notes receivable	0	76
Related party payables	3	5
Related party long-term debt	$ 12	$ 62

Amount of receivables arising from transactions with related parties due within one year or the normal operating cycle, if longer.

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Name:	us-gaap_AccountsReceivableRelatedPartiesCurrent
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant