Consolidated Statement of Comprehensive Income - 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]
Net income	$ 563	$ 581	$ 1,550	$ 1,404
Other comprehensive income (loss), net of related taxes:
Foreign currency translation, net of related taxes of ($14), ($51), ($24) and ($76), respectively	38	(145)	132	(555)
Net unrealized gains (losses) on available-for-sale securities, net of reclassification adjustment and net of related taxes of ($11), $27, $347 and ($48), respectively	(13)	37	533	(106)
Net unrealized gains (losses) on available-for-sale securities designated in fair value hedges, net of related taxes of $9, ($10), ($6) and ($5), respectively	13	(16)	(9)	(9)
Other-than-temporary impairment on held-to-maturity securities related to factors other than credit, net of related taxes of $1, $2, $3 and $6, respectively	2	4	5	11
Net unrealized gains (losses) on cash flow hedges, net of related taxes of ($27), $17, ($144) and $39, respectively	(39)	26	(213)	46
Net unrealized gains (losses) on retirement plans, net of related taxes of ($1), $3, $2 and $4, respectively	3	4	1	19
Other comprehensive income (loss)	4	(90)	449	(594)
Total comprehensive income	$ 567	$ 491	$ 1,999	$ 810