MORTGAGE BANKING AND OTHER SERVICED LOANS - Changes Related to MSRs - Fair Value Method (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024	Dec. 31, 2024
MSRs
Fair value as of beginning of the period			$ 1,491
Fair value at end of the period	$ 1,430		1,430
Residential mortgages
MSRs
Fair value as of beginning of the period	1,426	$ 1,568	1,491	$ 1,552
Amounts capitalized	42	28	117	71
Sales	0	0	(72)	0
Changes in unpaid principal balance	(41)	(46)	(120)	(135)
Changes in fair value	3	(49)	14	13
Fair value at end of the period	1,430	$ 1,501	1,430	$ 1,501
MSR loans	95,200		95,200		$ 95,600
Federal Home Loan Mortgage Corporation (FHLMC)
MSRs
MSR loans	$ 10,500		$ 10,500