4. Property And Equipment (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Property and equipment, gross	$ 51,280	$ 49,864
Less accumulated depreciation	(26,707)	(25,219)
Total property and equipment	24,573	24,645
Land [Member]
Property and equipment, gross	1,747	1,747
Buildings And improvements [Member]
Property and equipment, gross	17,520	17,260
Machinery And Equipment [Member]
Property and equipment, gross	29,692	27,539
Vehicles [Member]
Property and equipment, gross	937	901
Office Equipment [Member]
Property and equipment, gross	838	734
Construction In Progress [Member]
Property and equipment, gross	$ 546	$ 1,683

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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