FAIR VALUE MEASUREMENTS - Schedule of Assets Measured on Recurring Basis Level 3 Rollforward (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Mortgage Servicing Rights
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	$ 1,426	$ 1,568	$ 1,491	$ 1,552
Issuances	42	28	117	71
Sales	0		(72)
Settlements	(41)	(46)	(120)	(135)
Changes in fair value recognized in earnings	3	(49)	14	13
Ending balance	1,430	1,501	1,430	1,501
Other Derivative Contracts
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	15	6	1	7
Issuances	21	18	55	47
Sales	0		0
Settlements	(33)	(27)	(60)	(50)
Changes in fair value recognized in earnings	1	0	8	(7)
Ending balance	$ 4	$ (3)	$ 4	$ (3)