4. Property And Equipment (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Property, plant and equipment, gross	$ 52,264	$ 49,864
Less accumulated depreciation	(27,229)	(25,219)
Property, plant and equipment, net	25,035	24,645
Land [Member]
Property, plant and equipment, gross	1,747	1,747
Buildings And improvements [Member]
Property, plant and equipment, gross	17,446	17,260
Machinery And Equipment [Member]
Property, plant and equipment, gross	30,598	27,539
Vehicles [Member]
Property, plant and equipment, gross	901	901
Office Equipment [Member]
Property, plant and equipment, gross	879	734
Construction In Progress [Member]
Property, plant and equipment, gross	$ 693	$ 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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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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