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, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Mortgage Servicing Rights
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	$ 1,568	$ 1,524	$ 1,552	$ 1,530
Issuances	28	47	71	104
Settlements	(46)	(42)	(135)	(124)
Change in fair value during the period recognized in earnings	(49)	91	13	110
Ending balance	1,501	1,620	1,501	1,620
Other Derivative Contracts
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	6	6	7	1
Issuances	18	17	47	52
Settlements	(27)	1	(50)	(11)
Change in fair value during the period recognized in earnings	0	(21)	(7)	(39)
Ending balance	$ (3)	$ 3	$ (3)	$ 3