Detail of Selected Balance Sheet Accounts (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Gross	$ 25,844	$ 24,848
Less accumulated depreciation	14,388	13,493
Total	11,456	11,355
Land [Member]
Gross	2,476	2,476
Buildings [Member]
Gross	8,501	8,207
Machinery And Equipment [Member]
Gross	$ 14,867	$ 14,165

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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