LOANS AND ALLOWANCE FOR CREDIT LOSSES - Allowances For Credit Losses (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended	12 Months Ended
Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023	Dec. 31, 2023
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	$ 21,031	$ 20,172	$ 22,517	$ 19,659	$ 19,659
Charge-offs	(305)	(431)	(1,122)	(1,066)	(1,383)
Recoveries	227	75	556	295
Net recoveries (charge-offs)	(78)	(356)	(566)	(771)
Provision (credit)	488	436	(510)	990
Ending balance	21,441	20,252	21,441	20,252	22,517
Cumulative effect adjustment for the adoption of ASC 326
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance				374	374
Cumulative Effect, Period of Adoption, Adjusted Balance
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance				20,033	20,033
Commercial and Industrial
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	4,894	4,121	5,055	3,373	3,373
Charge-offs	(18)	(81)	(18)	(281)
Recoveries	68	4	118	13
Net recoveries (charge-offs)	50	(77)	100	(268)
Provision (credit)	(48)	102	(259)	132
Ending balance	4,896	4,146	4,896	4,146	5,055
Commercial and Industrial \| Cumulative effect adjustment for the adoption of ASC 326
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance				909	909
Commercial and Industrial \| Cumulative Effect, Period of Adoption, Adjusted Balance
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance				4,282	4,282
Commercial Mortgages
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	10,530	10,994	12,026	11,576	11,576
Charge-offs	0	0	0	0
Recoveries	1	1	3	1
Net recoveries (charge-offs)	1	1	3	1
Provision (credit)	231	30	(1,267)	143
Ending balance	10,762	11,025	10,762	11,025	12,026
Commercial Mortgages \| Cumulative effect adjustment for the adoption of ASC 326
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance				(695)	(695)
Commercial Mortgages \| Cumulative Effect, Period of Adoption, Adjusted Balance
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance				10,881	10,881
Residential Mortgages
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	2,106	1,905	2,194	1,845	1,845
Charge-offs	(1)	0	(21)	0	(32)
Recoveries	8	0	57	0
Net recoveries (charge-offs)	7	0	36	0
Provision (credit)	105	(37)	(12)	39
Ending balance	2,218	1,868	2,218	1,868	2,194
Residential Mortgages \| Cumulative effect adjustment for the adoption of ASC 326
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance				(16)	(16)
Residential Mortgages \| Cumulative Effect, Period of Adoption, Adjusted Balance
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance				1,829	1,829
Consumer Loans
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	3,501	3,152	3,242	2,865	2,865
Charge-offs	(286)	(350)	(1,083)	(785)
Recoveries	150	70	378	281
Net recoveries (charge-offs)	(136)	(280)	(705)	(504)
Provision (credit)	200	341	1,028	676
Ending balance	3,565	3,213	3,565	3,213	3,242
Consumer Loans \| Cumulative effect adjustment for the adoption of ASC 326
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance				176	176
Consumer Loans \| Cumulative Effect, Period of Adoption, Adjusted Balance
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance				3,041	3,041
Unfunded Loan Commitment
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	756	1,041	919	0	0
Provision (credit)	76	13	(87)	(28)
Ending balance	$ 832	$ 1,054	832	1,054	919
Unfunded Loan Commitment \| Cumulative effect adjustment for the adoption of ASC 326
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance			$ 0	$ 1,082	1,082
Ending balance					$ 0

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 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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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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