FAIR VALUE MEASUREMENTS - Schedule of Assets Measured on Recurring Basis Level 3 Rollforward (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Mortgage Servicing Rights
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	$ 1,564	$ 1,496	$ 1,552	$ 1,530
Issuances	25	36	43	57
Settlements	(43)	(41)	(89)	(82)
Change in fair value during the period recognized in earnings	22	33	62	19
Ending balance	1,568	1,524	1,568	1,524
Other Derivative Contracts
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	8	13	7	1
Issuances	16	20	29	35
Settlements	(13)	(7)	(23)	(12)
Change in fair value during the period recognized in earnings	(5)	(20)	(7)	(18)
Ending balance	$ 6	$ 6	$ 6	$ 6