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, 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	$ 25,232	$ 22,665	$ 24,209	$ 21,388	$ 21,388
Charge-offs	(530)	(288)	(1,633)	(1,807)	(2,456)
Recoveries	3,093	202	4,130	467
Net recoveries (charge-offs)	2,563	(86)	2,497	(1,340)
Provision (credit)	(2,582)	1,066	(1,493)	3,597
Ending balance	25,213	23,645	25,213	23,645	24,209
Commercial and Industrial
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	4,213	4,524	4,524	4,520	4,520
Charge-offs	(135)	0	(136)	(777)
Recoveries	2,902	1	3,584	9
Net recoveries (charge-offs)	2,767	1	3,448	(768)
Provision (credit)	(2,937)	52	(3,929)	825
Ending balance	4,043	4,577	4,043	4,577	4,524
Commercial Real Estate
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	16,198	12,714	14,363	11,214	11,214
Charge-offs	0	0	(310)	0
Recoveries	0	1	1	3
Net recoveries (charge-offs)	0	1	(309)	3
Provision (credit)	267	1,023	2,411	2,521
Ending balance	16,465	13,738	16,465	13,738	14,363
Residential Mortgages
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	2,401	2,597	2,788	2,259	2,259
Charge-offs	0	0	(8)	0	0
Recoveries	1	5	33	16
Net recoveries (charge-offs)	1	5	25	16
Provision (credit)	35	31	(376)	358
Ending balance	2,437	2,633	2,437	2,633	2,788
Consumer Loans
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	2,420	2,830	2,534	3,395	3,395
Charge-offs	(395)	(288)	(1,179)	(1,030)
Recoveries	190	195	512	439
Net recoveries (charge-offs)	(205)	(93)	(667)	(591)
Provision (credit)	53	(40)	401	(107)
Ending balance	2,268	2,697	2,268	2,697	2,534
Unfunded Loan Commitment
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	659	548	586	842	842
Provision (credit)	(20)	(2)	53	(296)
Ending balance	$ 639	$ 546	$ 639	$ 546	$ 586

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
-Subparagraph (SX 210.9-03(7)(2))
-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
-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
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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 13
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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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

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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