Consolidated Statements of Comprehensive Income (Parenthetical) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Unrealized loss/gain on derivatives, income tax benefit/(expense)	$ (1)	$ (19)	$ 21
Foreign currency translation adjustments, income tax benefit/(expense)	0	0	5
Available-for-sale securities, income tax benefit/(expense)	0	3	2
Defined benefit plan, income tax benefit/(expense)	$ 0	$ (69)	$ 88