DERIVATIVES - Schedule of Fair Value Hedges (Details) - Interest rate swap - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
Interest And Dividend Income, Investment Securities
Derivative Instruments, Gain (Loss) [Line Items]
Hedged items	$ 50	$ (39)	$ 166	$ (174)
Derivatives	(50)	40	(168)	179
Amounts related to interest settlements on derivatives	13	28	24	53
Total net interest income recognized on fair value hedges	13	29	22	58
Interest Expense
Derivative Instruments, Gain (Loss) [Line Items]
Hedged items	(2)	(3)	(4)	0
Derivatives	2	3	4	0
Amounts related to interest settlements on derivatives	(3)	(3)	(5)	(7)
Total net interest income recognized on fair value hedges	$ (3)	$ (3)	$ (5)	$ (7)