Consolidated Statements Of Comprehensive Income (Loss) (Parenthetical) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Statement of Comprehensive Income [Abstract]
Foreign currency translation adjustments, tax	$ 6	$ 4	$ 18	$ 3
Unrealized gains (losses), tax	(15)	3	(32)	(5)
Reclassification adjustment for losses (gains) included in other income (expense), net, tax	$ (1)	$ (1)	$ (2)	$ (1)