Stockholders' Equity - Other Comprehensive Income (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Before Tax
Net unrealized gains (losses) on securities available for sale	$ (3,012)	$ 66	$ (7,299)	$ (1,446)
Net unrealized gains (losses) on hedging relationships	(634)	(68)	(2,227)	(834)
Foreign currency translation adjustments	4	4	14	17
Other	0	0	0	(1)
Other comprehensive income (loss), before tax	(3,642)	2	(9,512)	(2,264)
Provision (Benefit)
Net unrealized gains (losses) on securities available for sale	(724)	15	(1,758)	(349)
Net unrealized gains (losses) on hedging relationships	(151)	(17)	(535)	(202)
Foreign currency translation adjustments	56	(5)	71	(11)
Other	0	0	0	0
Other comprehensive income (loss), provision (benefit)	(819)	(7)	(2,222)	(562)
After Tax
Net unrealized gains (losses) on securities available for sale	(2,288)	51	(5,541)	(1,097)
Net unrealized gains (losses) on hedging relationships	(483)	(51)	(1,692)	(632)
Foreign currency translation adjustments	(52)	9	(57)	28
Other	0	0	0	(1)
Other comprehensive income (loss), net of tax	$ (2,823)	$ 9	$ (7,290)	$ (1,702)