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, 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	$ 22,665	$ 21,031	$ 21,388	$ 22,517	$ 22,517
Charge-offs	(288)	(305)	(1,807)	(1,122)	(1,873)
Recoveries	202	227	467	556
Net recoveries (charge-offs)	(86)	(78)	(1,340)	(566)
Provision (credit)	1,066	488	3,597	(510)
Ending balance	23,645	21,441	23,645	21,441	21,388
Commercial and Industrial
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	4,524	4,894	4,520	5,055	5,055
Charge-offs	0	(18)	(777)	(18)
Recoveries	1	68	9	118
Net recoveries (charge-offs)	1	50	(768)	100
Provision (credit)	52	(48)	825	(259)
Ending balance	4,577	4,896	4,577	4,896	4,520
Commercial Mortgages
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	12,714	10,530	11,214	12,026	12,026
Charge-offs	0	0	0	0
Recoveries	1	1	3	3
Net recoveries (charge-offs)	1	1	3	3
Provision (credit)	1,023	231	2,521	(1,267)
Ending balance	13,738	10,762	13,738	10,762	11,214
Residential Mortgages
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	2,597	2,106	2,259	2,194	2,194
Charge-offs	0	(1)	0	(21)	(21)
Recoveries	5	8	16	57
Net recoveries (charge-offs)	5	7	16	36
Provision (credit)	31	105	358	(12)
Ending balance	2,633	2,218	2,633	2,218	2,259
Consumer Loans
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	2,830	3,501	3,395	3,242	3,242
Charge-offs	(288)	(286)	(1,030)	(1,083)
Recoveries	195	150	439	378
Net recoveries (charge-offs)	(93)	(136)	(591)	(705)
Provision (credit)	(40)	200	(107)	1,028
Ending balance	2,697	3,565	2,697	3,565	3,395
Unfunded Loan Commitment
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	548	756	842	919	919
Provision (credit)	(2)	76	(296)	(87)
Ending balance	$ 546	$ 832	$ 546	$ 832	$ 842