Consolidated Statements Of Comprehensive Income (Unaudited) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Statement of Comprehensive Income [Abstract]
Net income	$ 441	$ 520
Other comprehensive income (loss), net of tax:
Foreign currency translation adjustments	(2)	37
Change in unrealized gains and losses on cash flow hedges	36	(36)
Change in unrealized gains and losses on available-for-sale securities	6	(7)
Other comprehensive income (loss)	40	(6)
Comprehensive income	$ 481	$ 514

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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