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LOANS AND ALLOWANCE FOR CREDIT LOSSES - Summary of Loans by Type (Details) - USD ($)	Sep. 30, 2025	Jun. 30, 2025	Dec. 31, 2024	Sep. 30, 2024	Jun. 30, 2024	Dec. 31, 2023
LOANS AND ALLOWANCE FOR CREDIT LOSSES
Loans receivable	$ 1,945,107,000		$ 1,895,848,000
Allowance for credit losses on loans	(23,474,000)	$ (21,699,000)	(20,035,000)	$ (20,442,000)	$ (20,382,000)	$ (19,208,000)
Loans, net	1,921,633,000		1,875,813,000
Net of deferred loan origination fees	4,021,000		4,136,000
Commercial \| Commercial real estate - non-owner occupied
LOANS AND ALLOWANCE FOR CREDIT LOSSES
Loans receivable	765,366,000		739,565,000
Allowance for credit losses on loans	(13,823,000)	(13,093,000)	(11,964,000)	(11,918,000)	(12,177,000)	(12,010,000)
Commercial \| Commercial real estate - owner occupied
LOANS AND ALLOWANCE FOR CREDIT LOSSES
Loans receivable	260,365,000		261,071,000
Allowance for credit losses on loans	(3,231,000)	(3,055,000)	(2,844,000)	(2,873,000)	(2,901,000)	(2,116,000)
Commercial \| All other commercial loans
LOANS AND ALLOWANCE FOR CREDIT LOSSES
Loans receivable	449,175,000		423,277,000
Allowance for credit losses on loans	(4,376,000)	(3,891,000)	(3,361,000)	(3,424,000)	(3,678,000)	(2,918,000)
Residential mortgage loans
LOANS AND ALLOWANCE FOR CREDIT LOSSES
Loans receivable	396,810,000		408,009,000
Allowance for credit losses on loans	(1,709,000)	(1,314,000)	(1,356,000)	(1,760,000)	(1,112,000)	(1,764,000)
Consumer loans
LOANS AND ALLOWANCE FOR CREDIT LOSSES
Loans receivable	73,391,000		63,926,000
Allowance for credit losses on loans	$ (335,000)	$ (346,000)	$ (510,000)	$ (467,000)	$ (514,000)	$ (400,000)