DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES - Schedule of Effect of Cash Flow Hedging on Income Statement (Details) - USD ($)	3 Months Ended
	Mar. 31, 2025	Mar. 31, 2024
Derivative [Line Items]
Interest Income - Loans and Leases	$ 480,000,000	$ 481,000,000
Interest Expense - Short-Term Borrowings	14,000,000	28,000,000
Interest rate contracts
Derivative [Line Items]
Amount of gain (loss) reclassified from AOCI into net income	0	0
Interest rate contracts | Interest Income - Loans and Leases
Derivative [Line Items]
Amount of gain (loss) reclassified from AOCI into net income	(8,000,000)	(12,000,000)
Interest rate contracts | Interest Expense - Short-Term Borrowings
Derivative [Line Items]
Amount of gain (loss) reclassified from AOCI into net income	$ 0	$ 4,000,000