Revenues - Receivables (Details) - USD ($) $ in Millions	Sep. 30, 2019	Jan. 01, 2018
Revenue from Contract with Customer [Abstract]
Receivables for Product and Services in Accounts Receivable, Net	$ 1,195	$ 1,051

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.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant