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	9 Months Ended	12 Months Ended
Sep. 30, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025	Dec. 31, 2025
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	$ 70,598	$ 66,552	$ 68,995	$ 85,960	$ 85,960
Provision for credit losses	1,200	2,000	4,908	11,800
Loans charged-off	(3,101)	(573)	(5,728)	(30,193)	(30,414)
Recoveries	133	189	655	601
Net loans (charged-off) recovered	(2,968)	(384)	(5,073)	(29,592)
Ending balance	68,830	68,168	68,830	68,168	68,995
Unallocated
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	598	400	325	383	383
Provision for credit losses	297	(29)	570	(12)
Loans charged-off	0	0	0	0
Recoveries	0	0	0	0
Net loans (charged-off) recovered	0	0	0	0
Ending balance	895	371	895	371	325
Total commercial loans \| Commercial and Industrial
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	28,752	25,882	28,436	45,539	45,539
Provision for credit losses	785	1,447	3,044	10,335
Loans charged-off	(2,871)	(222)	(4,951)	(28,848)
Recoveries	35	42	172	123
Net loans (charged-off) recovered	(2,836)	(180)	(4,779)	(28,725)
Ending balance	26,701	27,149	26,701	27,149	28,436
Total commercial loans \| Commercial Real Estate and Multifamily Residential
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	30,655	31,082	30,163	30,865	30,865
Provision for credit losses	(314)	(197)	62	(32)
Loans charged-off	0	0	0	0
Recoveries	26	27	142	79
Net loans (charged-off) recovered	26	27	142	79
Ending balance	30,367	30,912	30,367	30,912	30,163
Total commercial loans \| Agri-business and Agricultural
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	3,258	3,299	3,315	3,541	3,541
Provision for credit losses	(27)	(80)	(84)	(322)
Loans charged-off	0	0	0	0
Recoveries	0	0	0	0
Net loans (charged-off) recovered	0	0	0	0
Ending balance	3,231	3,219	3,231	3,219	3,315
Total commercial loans \| Other Commercial
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	1,082	720	1,041	743	743
Provision for credit losses	(9)	(29)	32	(52)
Loans charged-off	0	0	0	0
Recoveries	0	0	0	0
Net loans (charged-off) recovered	0	0	0	0
Ending balance	1,073	691	1,073	691	1,041
Total consumer loans \| Consumer 1-4 Family Mortgage
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	4,366	3,590	3,996	3,358	3,358
Provision for credit losses	200	460	576	878
Loans charged-off	(15)	(4)	(127)	(226)
Recoveries	8	16	114	52
Net loans (charged-off) recovered	(7)	12	(13)	(174)
Ending balance	4,559	4,062	4,559	4,062	3,996
Total consumer loans \| Other Consumer
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	1,887	1,579	1,719	1,531	1,531
Provision for credit losses	268	428	708	1,005
Loans charged-off	(215)	(347)	(650)	(1,119)
Recoveries	64	104	227	347
Net loans (charged-off) recovered	(151)	(243)	(423)	(772)
Ending balance	$ 2,004	$ 1,764	$ 2,004	$ 1,764	$ 1,719

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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477657/942-210-S45-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478478/942-210-S50-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478546/942-210-S99-1

Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
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-Publisher FASB
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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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