Consolidated Statements of Comprehensive Income (Parenthetical) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Other Comprehensive Income (Loss):
Tax on foreign currency translation	$ 17	$ (34)
Defined benefit plans:
Tax on amortization of prior service cost and unrecognized gains and losses included in total benefit cost	8	9
Tax on decrease (increase) in net actuarial losses	(1)	0
Tax on deferred derivative gains (losses)	(1)	2
Tax on reclassification adjustment for amounts recognized in income	(1)	(1)
Tax on unrealized investment gains	$ 0	$ 4