ALLOWANCE FOR CREDIT LOSSES FOR LOANS - Roll Forward (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended	12 Months Ended
Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024	Dec. 31, 2024
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	$ 18,700	$ 19,000	$ 17,900	$ 22,000	$ 22,000
Charge-offs	(839)	(1,598)	(1,040)	(5,161)
Recoveries	6	53	92	168
Provision for (reversal of) credit losses	2,933	855	3,848	1,303
Ending balance	20,800	18,310	20,800	18,310	17,900
Reserve for unfunded commitments
Beginning balance	530	200	600	225	225
Provision for (reversal of) credit losses	40	390	(30)	365
Ending balance	570	590	570	590	600
Commercial and industrial
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	4,467	3,987	4,681	4,216	4,216
Charge-offs		(1,031)	(193)	(1,387)
Recoveries	6	53	21	68
Provision for (reversal of) credit losses	(35)	1,991	(71)	2,103
Ending balance	4,438	5,000	4,438	5,000	4,681
Construction and land
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	141	105	72	298	298
Provision for (reversal of) credit losses	134	13	203	(180)
Ending balance	275	118	275	118	72
Commercial real estate
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	12,327	13,695	11,365	16,498	16,498
Charge-offs	(839)	(566)	(839)	(3,772)
Recoveries			69
Provision for (reversal of) credit losses	2,541	(1,670)	3,434	(1,267)
Ending balance	14,029	11,459	14,029	11,459	11,365
Residential
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	1,761	1,205	1,780	979	979
Charge-offs			(1)
Recoveries			1	99
Provision for (reversal of) credit losses	291	523	272	650
Ending balance	2,052	1,728	2,052	1,728	1,780
Consumer
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	4	8	2	9	9
Charge-offs		(1)	(7)	(2)
Recoveries			1	1
Provision for (reversal of) credit losses	2	(2)	10	(3)
Ending balance	$ 6	$ 5	$ 6	$ 5	$ 2

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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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 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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Amount of expected credit loss for credit exposure on off-balance-sheet commitment, including but not limited to, loan commitment, standby letter of credit, financial guarantee not accounted for as insurance. Excludes off-balance sheet credit exposure accounted for as insurance and instrument accounted for under derivatives and hedging.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479344/326-20-45-2

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 460
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482454/460-10-45-1

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Amount of expense (reversal of expense) for expected credit loss for off-balance sheet credit exposure. Excludes off-balance sheet credit exposure accounted for as insurance and instrument accounted for under derivatives and hedging.

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