Stockholders' Equity - Reclassifications from AOCI (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Jun. 30, 2022	Dec. 31, 2021	Jun. 30, 2021	Dec. 31, 2020
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Interest income (loss)	$ 7,003	$ 6,156	$ 19,917	$ 17,721
Interest expense	1,197	382	2,162	1,217
Non-interest income (loss)	192	245	634	598
Income (loss) from continuing operations before income taxes	2,187	3,986	7,696	12,750
Income tax provision (benefit)	493	882	1,568	2,782
Net income	1,694	3,104	6,128	9,965
Accumulated other comprehensive income (loss)	(10,704)		(10,704)			$ 374
Other comprehensive income (loss), net of tax	(3,788)	(432)	(11,078)	(2,134)
Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net income	(6)	256	146	747
Securities available for sale | Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Non-interest income (loss)	(3)	2	(9)	6
Income tax provision (benefit)	(1)	0	(2)	1
Net income	(2)	2	(7)	5
Hedging Relationships
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Accumulated other comprehensive income (loss)	(2,378)	535	(2,378)	535	$ (1,574)	118	$ 730	$ 1,362
Other comprehensive income (loss) before reclassifications	(809)	57	(2,344)	(88)
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	5	(252)	(152)	(739)
Other comprehensive income (loss), net of tax	(804)	(195)	(2,496)	(827)
Hedging Relationships | Interest rate contracts | Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Interest income (loss)	(86)	250	104	730
Hedging Relationships | Foreign exchange contracts | Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Interest income (loss)	2	0	1	1
Interest expense	(1)	0	(2)	(2)
Non-interest income (loss)	79	83	97	245
Income (loss) from continuing operations before income taxes	(6)	333	200	974
Income tax provision (benefit)	(1)	81	48	235
Net income	(5)	252	152	739
Foreign Currency Translation Adjustments
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Accumulated other comprehensive income (loss)	(126)	(30)	(126)	(30)	(78)	(21)	(3)	(31)
Other comprehensive income (loss) before reclassifications	(48)	(27)	(105)	1
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	0	0	0	0
Other comprehensive income (loss), net of tax	(48)	(27)	(105)	1
Other
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Accumulated other comprehensive income (loss)	(21)	(26)	(21)	(26)	(20)	(20)	(24)	(23)
Other comprehensive income (loss) before reclassifications	0	0	0	0
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	(1)	(2)	(1)	(3)
Other comprehensive income (loss), net of tax	(1)	(2)	(1)	(3)
Other | Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Income (loss) from continuing operations before income taxes	1	3	1	4
Income tax provision (benefit)	0	1	0	1
Net income	1	2	1	3
Accumulated Other Comprehensive Income (Loss)
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Accumulated other comprehensive income (loss)	(10,704)	1,360	(10,704)	1,360	$ (6,916)	$ 374	$ 1,792	$ 3,494
Other comprehensive income (loss) before reclassifications	(3,794)	(176)	(10,932)	(1,387)
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	6	(256)	(146)	(747)
Other comprehensive income (loss), net of tax	$ (3,788)	$ (432)	$ (11,078)	$ (2,134)