LOANS AND LEASES - Troubled Debt Restructurings (Detail) $ in Millions	3 Months Ended
Mar. 31, 2019 USD ($) Contract	Mar. 31, 2018 USD ($) Contract
Financing Receivable, Modifications [Line Items]
Number of Contracts \| Contract	42	225
Pre- Modification Outstanding Recorded Investment	$ 2	$ 4
Post- Modification Outstanding Recorded Investment	$ 2	$ 3
Commercial Real Estate [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| Contract	1	1
Pre- Modification Outstanding Recorded Investment	$ 0	$ 0
Post- Modification Outstanding Recorded Investment	$ 0	$ 0
Commercial and Industrial [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| Contract	12	1
Pre- Modification Outstanding Recorded Investment	$ 1	$ 2
Post- Modification Outstanding Recorded Investment	$ 1	$ 1
Total Commercial Loans and Leases [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| Contract	13	2
Pre- Modification Outstanding Recorded Investment	$ 1	$ 2
Post- Modification Outstanding Recorded Investment	$ 1	$ 1
Direct Installment [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| Contract	18	182
Pre- Modification Outstanding Recorded Investment	$ 1	$ 1
Post- Modification Outstanding Recorded Investment	$ 1	$ 1
Residential Mortgages [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| Contract	3	11
Pre- Modification Outstanding Recorded Investment	$ 0	$ 1
Post- Modification Outstanding Recorded Investment	$ 0	$ 1
Indirect Installment [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| Contract		9
Pre- Modification Outstanding Recorded Investment		$ 0
Post- Modification Outstanding Recorded Investment		$ 0
Consumer Lines of Credit [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| Contract	8	21
Pre- Modification Outstanding Recorded Investment	$ 0	$ 0
Post- Modification Outstanding Recorded Investment	$ 0	$ 0
Consumer Loan [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| Contract	29	223
Pre- Modification Outstanding Recorded Investment	$ 1	$ 2
Post- Modification Outstanding Recorded Investment	$ 1	$ 2

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953676-111524

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