GOODWILL AND CORE DEPOSIT INTANGIBLES - Schedule of Changes in Core Deposit Intangibles (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Finite-lived Intangible Assets [Roll Forward]
Less: amortization for the period	$ (13)	$ (15)	$ (41)	$ (47)
Core Deposits
Finite-lived Intangible Assets [Roll Forward]
Balance at beginning of period, net of accumulated amortization			249
Less: amortization for the period			41
Balance at end of period, net of accumulated amortization	$ 208		$ 208