ALLOWANCE FOR CREDIT LOSSES AND CREDIT QUALITY - Allowance for Loan Losses by Portfolio Segment (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2023	Mar. 31, 2022
Financing Receivable, Allowance for Credit Loss [Line Items]
Beginning balance	$ 72,606	$ 67,773
Provision for credit losses	4,350	417
Loans charged-off	(5,896)	(740)
Recoveries	155	76
Net loans (charged-off) recovered	(5,741)	(664)
Ending balance	71,215	67,526
Unallocated
Financing Receivable, Allowance for Credit Loss [Line Items]
Beginning balance	554	450
Provision for credit losses	286	32
Loans charged-off	0	0
Recoveries	0	0
Net loans (charged-off) recovered	0	0
Ending balance	840	482
Commercial Portfolio Segment \| Commercial and Industrial
Financing Receivable, Allowance for Credit Loss [Line Items]
Beginning balance	35,290	30,595
Provision for credit losses	1,504	730
Loans charged-off	(5,644)	(19)
Recoveries	40	16
Net loans (charged-off) recovered	(5,604)	(3)
Ending balance	31,190	31,322
Commercial Portfolio Segment \| Commercial Real Estate and Multifamily Residential
Financing Receivable, Allowance for Credit Loss [Line Items]
Beginning balance	27,394	26,535
Provision for credit losses	1,642	319
Loans charged-off	0	(597)
Recoveries	0	0
Net loans (charged-off) recovered	0	(597)
Ending balance	29,036	26,257
Commercial Portfolio Segment \| Agri-business and Agricultural
Financing Receivable, Allowance for Credit Loss [Line Items]
Beginning balance	4,429	5,034
Provision for credit losses	192	(273)
Loans charged-off	0	0
Recoveries	0	0
Net loans (charged-off) recovered	0	0
Ending balance	4,621	4,761
Commercial Portfolio Segment \| Other Commercial
Financing Receivable, Allowance for Credit Loss [Line Items]
Beginning balance	917	1,146
Provision for credit losses	117	(88)
Loans charged-off	0	0
Recoveries	0	0
Net loans (charged-off) recovered	0	0
Ending balance	1,034	1,058
Consumer Portfolio Segment \| Consumer 1-4 Family Mortgage
Financing Receivable, Allowance for Credit Loss [Line Items]
Beginning balance	3,001	2,866
Provision for credit losses	394	(248)
Loans charged-off	0	(22)
Recoveries	3	10
Net loans (charged-off) recovered	3	(12)
Ending balance	3,398	2,606
Consumer Portfolio Segment \| Other Consumer
Financing Receivable, Allowance for Credit Loss [Line Items]
Beginning balance	1,021	1,147
Provision for credit losses	215	(55)
Loans charged-off	(252)	(102)
Recoveries	112	50
Net loans (charged-off) recovered	(140)	(52)
Ending balance	$ 1,096	$ 1,040

Amount excluding accrued interest, of allowance for credit loss on financing receivable. Excludes net investment in lease.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 45
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=124255206&loc=SL82895884-210446

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Amount, excluding accrued interest, of increase in allowance for credit loss on financing receivable from recovery. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 13
-Subparagraph (e)
-URI https://asc.fasb.org/extlink&oid=124255953&loc=SL82919249-210447

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Amount, excluding accrued interest, of decrease in allowance for credit loss on financing receivable from writeoff. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 13
-Subparagraph (d)
-URI https://asc.fasb.org/extlink&oid=124255953&loc=SL82919249-210447

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Amount, excluding accrued interest, of decrease (increase) in allowance for credit loss on financing receivable from writeoff (recovery). Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 13
-URI https://asc.fasb.org/extlink&oid=124255953&loc=SL82919249-210447

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+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 13
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=124255953&loc=SL82919249-210447

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