LOANS AND LEASES - Troubled Debt Restructurings (Detail) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2020 USD ($) Contract	Jun. 30, 2019 USD ($) Contract	Jun. 30, 2020 USD ($) Contract	Jun. 30, 2019 USD ($) Contract
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts \| Contract	54	41	115	81
Pre- Modification Outstanding Recorded Investment	$ 9	$ 8	$ 15	$ 11
Post- Modification Outstanding Recorded Investment	$ 8	$ 8	$ 13	$ 10
Total Commercial Loans and Leases [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts \| Contract	20	13	33	25
Pre- Modification Outstanding Recorded Investment	$ 7	$ 7	$ 9	$ 9
Post- Modification Outstanding Recorded Investment	$ 6	$ 7	$ 7	$ 8
Commercial Real Estate [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts \| Contract	11	11	16	12
Pre- Modification Outstanding Recorded Investment	$ 5	$ 3	$ 6	$ 4
Post- Modification Outstanding Recorded Investment	$ 5	$ 4	$ 5	$ 4
Commercial and Industrial [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts \| Contract	9	2	16	13
Pre- Modification Outstanding Recorded Investment	$ 2	$ 4	$ 3	$ 5
Post- Modification Outstanding Recorded Investment	$ 1	$ 3	$ 2	$ 4
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	34	28	82	56
Pre- Modification Outstanding Recorded Investment	$ 2	$ 1	$ 6	$ 2
Post- Modification Outstanding Recorded Investment	$ 2	$ 1	$ 6	$ 2
Direct Installment [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts \| Contract	19	14	38	32
Pre- Modification Outstanding Recorded Investment	$ 1	$ 1	$ 3	$ 1
Post- Modification Outstanding Recorded Investment	$ 1	$ 1	$ 3	$ 1
Residential Mortgages [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts \| Contract	2	7	16	10
Pre- Modification Outstanding Recorded Investment	$ 1	$ 0	$ 2	$ 1
Post- Modification Outstanding Recorded Investment	$ 1	$ 0	$ 2	$ 1
Consumer Lines of Credit [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts \| Contract	13	7	28	14
Pre- Modification Outstanding Recorded Investment	$ 0	$ 0	$ 1	$ 0
Post- Modification Outstanding Recorded Investment	$ 0	$ 0	$ 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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