PREMISES AND EQUIPMENT - Premises and Equipment (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Premises and equipment [Abstract]
Premises and equipment, gross	$ 89,293	$ 89,088
Less accumulated depreciation and amortization	69,174	66,671
Net book value	20,119	22,417
Depreciation expense	2,918	3,112	$ 3,437
Land
Premises and equipment [Abstract]
Premises and equipment, gross	4,803	4,803
Buildings
Premises and equipment [Abstract]
Premises and equipment, gross	41,957	41,408
Projects in progress
Premises and equipment [Abstract]
Premises and equipment, gross	65	113
Equipment and furniture
Premises and equipment [Abstract]
Premises and equipment, gross	37,183	37,007
Leasehold improvements
Premises and equipment [Abstract]
Premises and equipment, gross	$ 5,285	$ 5,757

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ References

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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ References

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