Property and Equipment - Schedule of Property and Equipment (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Property, Plant and Equipment [Line Items]
Property and equipment, Gross	$ 21,712	$ 21,541
Accumulated depreciation and amortization	(15,530)	(15,210)
Property and equipment, net	6,182	6,331
Land and Office Building [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, Gross	7,919	7,819
Furniture and Equipment [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, Gross	5,438	6,097
Software [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, Gross	7,916	7,366
Automobiles [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, Gross	74	74
Finance Lease Right-of-use Assets [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, Gross	$ 365	$ 185

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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