Parent Company Financial Statements - Statement of Income (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Condensed Financial Statements, Captions [Line Items]
Total revenue	$ 11,945	$ 12,148	$ 12,027
Other	1,529	1,075	896
Total expenses	9,583	8,801	8,889
Income tax expense	372	553	478
Equity in undistributed income of consolidated subsidiaries and unconsolidated entities:
Net income	1,944	2,774	2,693
Parent Company
Condensed Financial Statements, Captions [Line Items]
Cash dividends from consolidated banking subsidiary	4,550	1,500	0
Cash dividends from consolidated non-banking subsidiaries and unconsolidated entities	320	198	170
Other, net	274	69	49
Total revenue	5,144	1,767	219
Interest expense	975	426	239
Other	198	93	315
Total expenses	1,173	519	554
Income tax expense	(224)	(121)	(153)
Income (Loss) before equity in undistributed income of consolidated subsidiaries and unconsolidated entities	4,195	1,369	(182)
Equity in undistributed income of consolidated subsidiaries and unconsolidated entities:
Consolidated banking subsidiary	(2,464)	1,275	2,657
Consolidated non-banking subsidiaries and unconsolidated entities	213	130	218
Net income	$ 1,944	$ 2,774	$ 2,693