DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES - Effect of Cash Flow Hedging on Income Statement (Detail) (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Derivative [Line Items]
Loans and leases, including fees	$ 266	$ 269
Short-term borrowings	14	26
Interest rate contracts [Member]
Derivative [Line Items]
Amount of gain (loss) reclassified from AOCI into net income	0
Amount of Gain (Loss) Reclassified from AOCI into Income		0
Interest Income - Loans and Leases [Member] \| Interest rate contracts [Member]
Derivative [Line Items]
Amount of gain (loss) reclassified from AOCI into net income	0
Amount of Gain (Loss) Reclassified from AOCI into Income		0
Interest Expense - Short-Term Borrowings [Member] \| Interest rate contracts [Member]
Derivative [Line Items]
Amount of gain (loss) reclassified from AOCI into net income	$ (1)
Amount of Gain (Loss) Reclassified from AOCI into Income		$ 1

The effective portion of net gain (loss) reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments.

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-Publisher FASB
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The aggregate interest and fee income generated by: (1) loans the Entity has positive intent and ability to hold for the foreseeable future, or until maturity or payoff, including commercial and consumer loans, whether domestic or foreign, which may consist of: (a) industrial and agricultural; (b) real estate; and (c) real estate construction loans; (d) trade financing; (e) lease financing; (f) home equity lines-of-credit; (g) automobile and other vehicle loans; and (h) credit card and other revolving-type loans and (2) loans and leases held-for-sale which may include mortgage loans, direct financing, and sales-type leases.

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The aggregate interest expense incurred on short-term borrowings including commercial paper and Federal funds purchased and securities sold under agreements to repurchase.

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Amount, before tax, of reclassification of gain (loss) from accumulated other comprehensive income (AOCI) for derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness.

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