Consolidated Statement of Comprehensive Income - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Statement of Comprehensive Income [Abstract]
Net income	$ 508	$ 659
Other comprehensive income (loss), net of related taxes:
Foreign currency translation, net of related taxes of ($8), $21 and ($11), respectively	(26)	151
Net unrealized gains (losses) on available-for-sale securities, net of reclassification adjustment and net of related taxes of ($134), $272 and ($119), respectively	272	(149)
Net unrealized gains (losses) on available-for-sale securities designated in fair value hedges, net of related taxes of $9, $16 and $16, respectively	(2)	18
Other-than-temporary impairment on held-to-maturity securities related to factors other than credit, net of related taxes of $2, $3 and $5, respectively	0	0
Net unrealized gains (losses) on cash flow hedges, net of related taxes of ($17), ($181) and ($42), respectively	24	(97)
Net unrealized gains (losses) on retirement plans, net of related taxes of $8, $8 and $1, respectively	(8)	12
Other comprehensive income (loss)	260	(65)
Total comprehensive income	$ 768	$ 594