ALLOWANCE FOR CREDIT LOSSES AND CREDIT QUALITY - Additional Information (Details)	3 Months Ended	12 Months Ended
Mar. 31, 2024 USD ($)	Mar. 31, 2024 USD ($) loan	Dec. 31, 2023 USD ($)
Financing Receivable, Allowance for Credit Loss [Line Items]
Loan amount of credit quality analysis	$ 250,000
Loans receivable before allowance for credit loss	4,997,559,000	$ 4,997,559,000	$ 4,916,534,000
PPP \| Pass
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans receivable before allowance for credit loss	$ 1,200,000	$ 1,200,000	$ 1,300,000
Working capital lines of credit loans \| Commercial and industrial loans: \| 30-59 Days Past Due
Financing Receivable, Allowance for Credit Loss [Line Items]
Number of loans modified \| loan		1

The minimum loan amount required for credit quality analysis.

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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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name Regulation S-K (SK)
-Number 229
-Section 1405
-Paragraph c
-Publisher SEC

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

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- Definition

Amortized cost excluding accrued interest, before allowance for credit loss, of financing receivable. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479344/326-20-45-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
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-Paragraph 3B
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-3B

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
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-Paragraph 5
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-5

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- Definition

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

+ References

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-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
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