Premises and Equipment - Components of Premises and Equipment Included in the Consolidated Balance Sheets (Detail) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Property, Plant and Equipment [Line Items]
Premises and equipment, Gross	$ 36,262	$ 37,132
Less accumulated depreciation	14,503	14,432
Premises and equipment, net	21,759	22,700
Land [Member]
Property, Plant and Equipment [Line Items]
Premises and equipment, Gross	6,546	6,555
Land Improvements [Member]
Property, Plant and Equipment [Line Items]
Premises and equipment, Gross	1,141	1,153
Buildings [Member]
Property, Plant and Equipment [Line Items]
Premises and equipment, Gross	22,504	22,467
Furniture and Equipment [Member]
Property, Plant and Equipment [Line Items]
Premises and equipment, Gross	$ 6,071	$ 6,957

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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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.

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