DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES (Derivatives Not Designated as Hedges) (Details) - Derivatives not designated as hedging instruments - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Derivative Instruments, Gain (Loss) [Line Items]
Other Noninterest Income/(Expense)	$ 10	$ 20	$ 38	$ 47
Customer-facing interest rate derivatives
Derivative Instruments, Gain (Loss) [Line Items]
Other Noninterest Income/(Expense)	4	11	17	22
Other interest rate derivatives
Derivative Instruments, Gain (Loss) [Line Items]
Other Noninterest Income/(Expense)	(2)	1	(1)	4
Foreign exchange derivatives
Derivative Instruments, Gain (Loss) [Line Items]
Other Noninterest Income/(Expense)	8	8	22	22
Purchased credit derivatives
Derivative Instruments, Gain (Loss) [Line Items]
Other Noninterest Income/(Expense)	$ 0	$ 0	$ 0	$ (1)