Property and Equipment - Schedule of Property and Equipment (Detail) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Property, Plant and Equipment [Line Items]
Property and equipment, Gross	$ 21,361	$ 21,221
Accumulated depreciation	(15,103)	(15,093)
Property and equipment, net	6,258	6,128
Land and Office Building [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, Gross	7,798	7,713
Furniture and Equipment [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, Gross	6,150	6,578
Software [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, Gross	7,339	6,856
Automobiles [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, Gross	$ 74	$ 74