DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES - Effect of Cash Flow Hedging on Income Statement (Detail) (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Derivative [Line Items]
Loans and leases, including fees	$ 245,000,000	$ 276,000,000	$ 511,000,000	$ 545,000,000
Short-term borrowings	$ 8,000,000	$ 22,000,000	22,000,000	48,000,000
Interest rate contracts [Member]
Derivative [Line Items]
Amount of gain (loss) reclassified from AOCI into net income			0	0
Interest Income - Loans and Leases [Member] | Interest rate contracts [Member]
Derivative [Line Items]
Amount of gain (loss) reclassified from AOCI into net income			1,000,000	(1,000,000)
Interest Expense - Short-Term Borrowings [Member] | Interest rate contracts [Member]
Derivative [Line Items]
Amount of gain (loss) reclassified from AOCI into net income			$ (5,000,000)	$ 3,000,000