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LOANS AND ALLOWANCE FOR CREDIT LOSSES - Summary of loans (Details) - USD ($) $ in Thousands	Jun. 30, 2026	Mar. 31, 2026	Dec. 31, 2025	Jun. 30, 2025	Mar. 31, 2025	Dec. 31, 2024
LOANS AND ALLOWANCE FOR CREDIT LOSSES
Total gross loans	$ 1,108,767		$ 802,446
Unearned discount and net deferred fees and costs	1,340		773
Total loans	1,110,107		803,219
Allowance for credit losses	(13,138)	$ (8,916)	(8,749)	$ (8,488)	$ (8,635)	$ (8,545)
Net loans	1,096,969		794,470
Residential real estate
LOANS AND ALLOWANCE FOR CREDIT LOSSES
Total gross loans	420,847		318,694
Allowance for credit losses	(3,832)	(2,831)	(2,721)	(2,460)	(2,522)	(2,564)
HELOCs
LOANS AND ALLOWANCE FOR CREDIT LOSSES
Total gross loans	22,241		17,092
Allowance for credit losses	(93)	(71)	(71)	(102)	(103)	(104)
Commercial real estate
LOANS AND ALLOWANCE FOR CREDIT LOSSES
Total gross loans	552,240		370,380
Allowance for credit losses	(8,385)	(5,390)	(5,355)	(5,399)	(5,533)	(5,396)
Commercial and industrial
LOANS AND ALLOWANCE FOR CREDIT LOSSES
Total gross loans	43,631		32,582
Allowance for credit losses	(518)	(374)	(375)	(372)	(318)	(313)
Consumer
LOANS AND ALLOWANCE FOR CREDIT LOSSES
Total gross loans	69,808		63,698
Allowance for credit losses	$ (310)	$ (250)	$ (227)	$ (155)	$ (159)	$ (168)