PARENT COMPANY FINANCIALS - Condensed Statements of Operations (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
OPERATING INCOME:
Total interest income	$ 9,663	$ 10,186	$ 10,204
OPERATING EXPENSE:
Salaries and employee benefits	2,798	2,657	2,599
Interest expense	3,810	4,553	3,963
All other expenses	662	722	973
Income tax expense (benefit)	497	379	422
NET INCOME	1,831	1,509	1,608
Total other comprehensive income (loss), net of tax	1,625	163	802
Total comprehensive income (loss)	3,456	1,672	2,410
Parent company
OPERATING INCOME:
Dividends	1,100	625	2,875
Interest	174	139	43
Management and service fees	64	67	69
All other operating income	1	1	1
Total interest income	1,357	841	2,996
OPERATING EXPENSE:
Salaries and employee benefits	33	36	39
Interest expense	350	263	129
All other expenses	34	32	31
Total operating expense	417	331	199
Income before income tax expense	940	510	2,797
Income tax expense (benefit)	(38)	(24)	(13)
Income before undistributed income of subsidiaries	978	534	2,810
NET INCOME	1,831	1,509	1,608
Total other comprehensive income (loss), net of tax	1,625	163	802
Total comprehensive income (loss)	3,456	1,672	2,410
Nonbank subsidiaries | Parent company
OPERATING INCOME:
Interest	8	9	8
Dividends	10	0	0
OPERATING EXPENSE:
Equity in undistributed income (losses) of subsidiaries	30	36	(39)
Bank subsidiaries | Parent company
OPERATING EXPENSE:
Equity in undistributed income (losses) of subsidiaries	$ 823	$ 939	$ (1,163)