Consolidated Statement of Comprehensive Income - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Statement of Comprehensive Income [Abstract]
Net income	$ 502	$ 368
Other comprehensive income (loss), net of related taxes:
Foreign currency translation, net of related taxes of $123 and $9, respectively	91	306
Net unrealized gains (losses) on available-for-sale securities, net of reclassification adjustment and net of related taxes of $131 and $171, respectively	201	260
Net unrealized gains (losses) on available-for-sale securities designated in fair value hedges, net of related taxes of $5 and ($12), respectively	6	(19)
Other-than-temporary impairment on held-to-maturity securities related to factors other than credit, net of related taxes of $1 and $1, respectively	1	1
Net unrealized gains (losses) on cash flow hedges, net of related taxes of ($51) and ($45), respectively	(70)	(68)
Net unrealized gains (losses) on retirement plans, net of related taxes of $3 and $2, respectively	6	(2)
Other comprehensive income (loss)	235	478
Total comprehensive income	$ 737	$ 846