LOAN COMMITMENTS AND OTHER RELATED ACTIVITIES - Contractual Amount of Financial Instruments with Off-Balance-Sheet Risk (Detail) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2020	Dec. 31, 2019
Affordable Housing Fund Investment
Other Commitments [Line Items]
Alternative investments unfunded investment commitments	$ 18,900
Small Business Investment Companies
Other Commitments [Line Items]
Alternative investments unfunded investment commitments	5,600
Other Investments
Other Commitments [Line Items]
Alternative investments unfunded investment commitments	10,500
Commitments to extend credit
Other Commitments [Line Items]
Fixed Rate	20,181	$ 473
Variable Rate	49,274	129,495
Unused lines of credit
Other Commitments [Line Items]
Fixed Rate	1,778	703
Variable Rate	1,334,060	1,049,632
Letters of credit
Other Commitments [Line Items]
Fixed Rate	157	134
Variable Rate	$ 9,202	$ 5,316

Alternative Investments, Unfunded Investment Commitments

No definition available.

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- Definition

Reflects the amount of cash required to fully fund agreements to provide advances to borrowers and lessees at stated interest rates.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 825
-Section 50
-Paragraph 1
-Subparagraph (b)(2)
-URI http://asc.fasb.org/extlink&oid=108315417&loc=d3e61044-112788

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
-Topic 942
-SubTopic 825
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=108315417&loc=d3e61082-112788

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- Definition

Reflects the amount of cash required to fully fund agreements to provide advances to borrowers and lessees at interest rates that increase or decrease depending on certain facts or circumstances.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 825
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=108315417&loc=d3e61082-112788

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 825
-Section 50
-Paragraph 1
-Subparagraph (b)(2)
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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