Revenue Recognition - Summary of Balances of Accounts Receivable and Contract Assets from Contracts with Customers (Details) - USD ($) $ in Millions	Sep. 30, 2019	Dec. 31, 2018
Revenue From Contract With Customer [Abstract]
Accounts receivable	$ 212	$ 205
Contract assets	6	7
Total	$ 218	$ 212

Amount, after allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business, classified as current.

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