Shareholders' Equity - Schedule of Accumulated Other Comprehensive (Loss) Income (Details) - USD ($) $ in Millions	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Equity [Abstract]
Net unrealized gains on cash flow hedges	$ 229	$ 293	$ 276
Net unrealized gains (losses) on available-for-sale securities portfolio	(225)	9	273
Net unrealized gains (losses) related to reclassified available-for-sale securities	25	(28)	39
Net unrealized gains (losses) on available-for-sale securities	(200)	(19)	312
Net unrealized losses on available-for-sale securities designated in fair value hedges	(86)	(109)	(121)
Other-than-temporary impairment on available-for-sale securities related to factors other than credit	0	0	1
Net unrealized gains (losses) on hedges of net investments in non-U.S. subsidiaries	95	(14)	(14)
Other-than-temporary impairment on held-to-maturity securities related to factors other than credit	(9)	(16)	(29)
Net unrealized losses on retirement plans	(194)	(183)	(272)
Foreign currency translation	(1,875)	(1,394)	(660)
Total	$ (2,040)	$ (1,442)	$ (507)