ALLOWANCE FOR CREDIT LOSSES AND CREDIT QUALITY - Schedule of Activity in the Allowance for Credit Losses by Portfolio Segment (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2025	Mar. 31, 2024	Dec. 31, 2024
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	$ 85,960	$ 71,972	$ 71,972
Provision for credit losses	6,800	1,520
Loans charged-off	(508)	(504)	(3,468)
Recoveries	181	192
Net loans (charged-off) recovered	(327)	(312)
Ending balance	92,433	73,180	85,960
Unallocated
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	383	372	372
Provision for credit losses	76	129
Loans charged-off	0	0
Recoveries	0	0
Net loans (charged-off) recovered	0	0
Ending balance	459	501	383
Commercial Portfolio Segment \| Commercial and Industrial
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	45,539	30,338	30,338
Provision for credit losses	6,741	542
Loans charged-off	(10)	(194)
Recoveries	32	34
Net loans (charged-off) recovered	22	(160)
Ending balance	52,302	30,720	45,539
Commercial Portfolio Segment \| Commercial Real Estate and Multifamily Residential
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	30,865	31,335	31,335
Provision for credit losses	(423)	717
Loans charged-off	0	0
Recoveries	26	26
Net loans (charged-off) recovered	26	26
Ending balance	30,468	32,078	30,865
Commercial Portfolio Segment \| Agri-business and Agricultural
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	3,541	4,150	4,150
Provision for credit losses	(41)	(38)
Loans charged-off	0	0
Recoveries	0	0
Net loans (charged-off) recovered	0	0
Ending balance	3,500	4,112	3,541
Commercial Portfolio Segment \| Other Commercial
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	743	1,129	1,129
Provision for credit losses	(20)	(107)
Loans charged-off	0	0
Recoveries	0	0
Net loans (charged-off) recovered	0	0
Ending balance	723	1,022	743
Consumer Portfolio Segment \| Consumer 1-4 Family Mortgage
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	3,358	3,474	3,474
Provision for credit losses	124	21
Loans charged-off	(24)	0
Recoveries	6	23
Net loans (charged-off) recovered	(18)	23
Ending balance	3,464	3,518	3,358
Consumer Portfolio Segment \| Other Consumer
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	1,531	1,174	1,174
Provision for credit losses	343	256
Loans charged-off	(474)	(310)
Recoveries	117	109
Net loans (charged-off) recovered	(357)	(201)
Ending balance	$ 1,517	$ 1,229	$ 1,531

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
-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

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- Definition

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
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

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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
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-6

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

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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
-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

Amount, excluding accrued interest, of credit loss expense (reversal of expense) on financing receivable. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

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