Parent Company Condensed Financial Information (Condensed Statement of Comprehensive Income) (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2022	Dec. 31, 2021		Dec. 31, 2020
Net financing revenue and other interest income (loss)		$ 6,850	$ 6,167		$ 4,703
Total other revenue		1,578	2,039		1,983
Total net revenue		8,428	8,206		6,686
Provision for credit losses		1,399	241		1,439
Total noninterest expense		4,687	4,110		3,833
Income (loss) from continuing operations before income tax benefit and undistributed (loss) income of subsidiaries		2,342	3,855		1,414
Income tax expense from continuing operations		627	790		328
Net income from continuing operations	[1]	1,715	3,065		1,086
Loss from discontinued operations, net of tax		(1)	(5)	[1]	(1)	[1]
Net income		1,714	3,060		1,085
Other comprehensive (loss) income, net of tax		(3,901)	(789)		508
Comprehensive (loss) income		(2,187)	2,271		1,593
Parent company
Net financing revenue and other interest income (loss)		(1,000)	(1,070)		(1,049)
Dividends from bank subsidiaries		3,150	3,450		1,150
Dividends from nonbank subsidiaries		1	27		66
Total other revenue		103	243		367
Total net revenue		2,254	2,650		534
Provision for credit losses		(32)	(106)		(68)
Total noninterest expense		665	650		693
Income (loss) from continuing operations before income tax benefit and undistributed (loss) income of subsidiaries		1,621	2,106		(91)
Income tax expense from continuing operations		(253)	(412)		(300)
Net income from continuing operations		1,874	2,518		209
Loss from discontinued operations, net of tax		(1)	(5)		(1)
Equity in undistributed earnings of subsidiaries		(159)	547		877
Net income		1,714	3,060		1,085
Other comprehensive (loss) income, net of tax		(3,901)	(789)		508
Comprehensive (loss) income		$ (2,187)	$ 2,271		$ 1,593

[1] Figures in the table may not recalculate exactly due to rounding. Earnings per share is calculated based on unrounded numbers.