CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Statement of Comprehensive Income [Abstract]
Net income	$ 232	$ 667	$ 607	$ 1,087
Other comprehensive income (loss):
Foreign currency translation adjustments	38	(399)	71	(247)
Derivative instrument adjustments and other, net of tax	(1)	11	(2)	8
Reclassification of (income) loss, net of tax	(3)	3	(4)	16
Net other comprehensive income (loss)	34	(385)	65	(223)
Comprehensive income	$ 266	$ 282	$ 672	$ 864

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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