Stockholders' Equity - Other Comprehensive Income (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Before Tax
Net unrealized gains (losses) on securities available for sale	$ (3,882)	$ (270)	$ (11,181)	$ (1,716)
Net unrealized gains (losses) on hedging relationships	(1,065)	(255)	(3,292)	(1,089)
Foreign currency translation adjustments	33	(6)	47	11
Other	(1)	(3)	(1)	(4)
Other comprehensive income (loss), before tax	(4,915)	(534)	(14,427)	(2,798)
Provision (Benefit)
Net unrealized gains (losses) on securities available for sale	(947)	(62)	(2,705)	(411)
Net unrealized gains (losses) on hedging relationships	(261)	(60)	(796)	(262)
Foreign currency translation adjustments	81	21	152	10
Other	0	(1)	0	(1)
Other comprehensive income (loss), provision (benefit)	(1,127)	(102)	(3,349)	(664)
After Tax
Net unrealized gains (losses) on securities available for sale	(2,935)	(208)	(8,476)	(1,305)
Net unrealized gains (losses) on hedging relationships	(804)	(195)	(2,496)	(827)
Foreign currency translation adjustments	(48)	(27)	(105)	1
Other	(1)	(2)	(1)	(3)
Other comprehensive loss, net of tax	$ (3,788)	$ (432)	$ (11,078)	$ (2,134)