LOANS AND LEASES - Troubled Debt Restructurings (Detail) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2020 USD ($) Contract	Sep. 30, 2019 USD ($) Contract	Sep. 30, 2020 USD ($) Contract	Sep. 30, 2019 USD ($) Contract
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts \| Contract	36	31	147	111
Pre- Modification Outstanding Recorded Investment	$ 4	$ 2	$ 18	$ 13
Post- Modification Outstanding Recorded Investment	$ 4	$ 2	$ 14	$ 11
Total Commercial Loans and Leases [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts \| Contract	11	5	43	30
Pre- Modification Outstanding Recorded Investment	$ 2	$ 0	$ 11	$ 9
Post- Modification Outstanding Recorded Investment	$ 2	$ 0	$ 8	$ 7
Commercial Real Estate [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts \| Contract	7	4	23	16
Pre- Modification Outstanding Recorded Investment	$ 2	$ 0	$ 8	$ 4
Post- Modification Outstanding Recorded Investment	$ 2	$ 0	$ 6	$ 4
Commercial and Industrial [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts \| Contract	4	1	19	14
Pre- Modification Outstanding Recorded Investment	$ 0	$ 0	$ 3	$ 5
Post- Modification Outstanding Recorded Investment	$ 0	$ 0	$ 2	$ 3
Other [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts \| Contract	0		1
Pre- Modification Outstanding Recorded Investment	$ 0		$ 0
Post- Modification Outstanding Recorded Investment	$ 0		$ 0
Consumer Loan [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts \| Contract	25	26	104	81
Pre- Modification Outstanding Recorded Investment	$ 2	$ 2	$ 7	$ 4
Post- Modification Outstanding Recorded Investment	$ 2	$ 2	$ 6	$ 4
Direct Installment [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts \| Contract	14	15	50	47
Pre- Modification Outstanding Recorded Investment	$ 1	$ 1	$ 3	$ 2
Post- Modification Outstanding Recorded Investment	$ 1	$ 1	$ 3	$ 2
Residential Mortgages [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts \| Contract	2	4	18	14
Pre- Modification Outstanding Recorded Investment	$ 1	$ 1	$ 3	$ 1
Post- Modification Outstanding Recorded Investment	$ 1	$ 1	$ 2	$ 1
Consumer Lines of Credit [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts \| Contract	9	7	36	20
Pre- Modification Outstanding Recorded Investment	$ 0	$ 0	$ 1	$ 1
Post- Modification Outstanding Recorded Investment	$ 0	$ 0	$ 1	$ 1

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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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