LOANS AND LEASES - Troubled Debt Restructurings (Detail) $ in Millions	3 Months Ended
Mar. 31, 2021 USD ($) Contract	Mar. 31, 2020 USD ($) Contract
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts \| Contract	34	60
Pre- Modification Outstanding Recorded Investment	$ 19	$ 5
Post- Modification Outstanding Recorded Investment	$ 19	$ 4
Total Commercial Loans and Leases [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts \| Contract	12	12
Pre- Modification Outstanding Recorded Investment	$ 17	$ 2
Post- Modification Outstanding Recorded Investment	$ 17	$ 1
Commercial Real Estate [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts \| Contract	11	5
Pre- Modification Outstanding Recorded Investment	$ 17	$ 1
Post- Modification Outstanding Recorded Investment	$ 17	$ 1
Commercial and Industrial [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts \| Contract	1	7
Pre- Modification Outstanding Recorded Investment	$ 0	$ 1
Post- Modification Outstanding Recorded Investment	$ 0	$ 0
Consumer Loan [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts \| Contract	22	48
Pre- Modification Outstanding Recorded Investment	$ 2	$ 3
Post- Modification Outstanding Recorded Investment	$ 2	$ 3
Direct Installment [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts \| Contract	10	19
Pre- Modification Outstanding Recorded Investment	$ 0	$ 2
Post- Modification Outstanding Recorded Investment	$ 0	$ 2
Residential Mortgages [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts \| Contract	2	14
Pre- Modification Outstanding Recorded Investment	$ 1	$ 1
Post- Modification Outstanding Recorded Investment	$ 1	$ 1
Consumer Lines of Credit [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts \| Contract	10	15
Pre- Modification Outstanding Recorded Investment	$ 1	$ 0
Post- Modification Outstanding Recorded Investment	$ 1	$ 0

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Number of financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953676-111524

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Amount, after troubled debt restructuring, of modified financing receivable.

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Amount, before troubled debt restructuring, of financing receivable to be modified.

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