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PREMISES AND EQUIPMENT - Components of premises and equipment (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Dec. 31, 2021
PREMISES AND EQUIPMENT
Premises and equipment	$ 96,087,000		$ 96,087,000		$ 97,613,000
Less accumulated depreciation	(40,493,000)		(40,493,000)		(39,196,000)
Premises and equipment, net	55,594,000		55,594,000		58,417,000
Depreciation expense	842,000	$ 871,000	2,520,000	$ 2,602,000
Loss on sale of premises and equipment			1,200,000
Proceeds from lessor for early termination of lease			1,500,000
Land
PREMISES AND EQUIPMENT
Premises and equipment	15,484,000		15,484,000		15,484,000
Buildings and leasehold improvements
PREMISES AND EQUIPMENT
Premises and equipment	62,260,000		62,260,000		64,298,000
Furniture and equipment
PREMISES AND EQUIPMENT
Premises and equipment	17,619,000		17,619,000		17,087,000
Vehicles
PREMISES AND EQUIPMENT
Premises and equipment	248,000		248,000		248,000
Construction in progress
PREMISES AND EQUIPMENT
Premises and equipment	$ 476,000		$ 476,000		$ 496,000