LOANS AND ALLOWANCE FOR CREDIT LOSSES - Loans by Class Modified as Troubled Debt Restructurings (Detail) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2020 USD ($) loan	Sep. 30, 2019 USD ($) loan	Sep. 30, 2020 USD ($) loan	Sep. 30, 2019 USD ($) loan
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans \| loan				12
Post-Modification Outstanding Recorded Investment				$ 17,889
Commercial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans \| loan	0	0	1	12
Pre- Modification Outstanding Recorded Investment	$ 0	$ 0	$ 5,000	$ 20,553
Post-Modification Outstanding Recorded Investment	$ 0	$ 0	$ 5,000	$ 17,889
Commercial \| Commercial and industrial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans \| loan	0	0	1	10
Pre- Modification Outstanding Recorded Investment	$ 0	$ 0	$ 5,000	$ 17,339
Post-Modification Outstanding Recorded Investment	$ 0	$ 0	$ 5,000	$ 17,020
Commercial \| SBA
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans \| loan		0		2
Pre- Modification Outstanding Recorded Investment		$ 0		$ 3,214
Post-Modification Outstanding Recorded Investment		$ 0		$ 869

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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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