Consolidated Statement of Comprehensive Income (Parenthetical) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Statement of Comprehensive Income [Abstract]
Foreign currency translation, Taxes	$ (110)	$ (19)	$ 13	$ (10)
Change in net unrealized losses on available-for-sale securities, Taxes	177	187	308	358
Change in net unrealized losses on available-for-sale securities designated in fair value hedges, Taxes	0	(3)	5	(15)
Other-than-temporary impairment on held-to-maturity securities related to factors other than credit, Taxes	0	1	1	2
Change in net unrealized losses on cash flow hedges, Taxes	(113)	(72)	(164)	(117)
Change in unrealized losses on retirement plans, Taxes	$ (1)	$ 1	$ 2	$ 3