Note 5 - Property, Plant and Equipment - Summary of Property, Plant and Equipment (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Property, plant and equipment, gross	$ 80,265	$ 74,421
Accumulated depreciation and amortization	(51,496)	(47,577)
	28,769	26,844
Land [Member]
Property, plant and equipment, gross	3,635	3,635
Buildings Improvements and Leaseholds [Member]
Property, plant and equipment, gross	18,519	18,192
Machinery, Equipment and Fixtures [Member]
Property, plant and equipment, gross	$ 58,111	$ 52,594

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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