CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Unaudited) - 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	$ 328	$ 402	$ 774	$ 902
Other comprehensive income (loss):
Foreign currency translation adjustment, net of tax	(2)	(11)	1	(10)
Unrealized gains (losses) on forward contracts designated as hedges, net of tax	(8)	48	(6)	36
Unrealized gains (losses) on investments, net of tax	4	7	(2)	4
Total other comprehensive income (loss)	(6)	44	(7)	30
Comprehensive income	$ 322	$ 446	$ 767	$ 932

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

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