Note 5 - Property, Plant and Equipment, Net - Summary of Property, Plant and Equipment (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Property, plant and equipment, gross	$ 95,963	$ 88,691
Accumulated depreciation and amortization	(59,319)	(55,866)
Property, plant and equipment, net	36,644	32,825
Land [Member]
Property, plant and equipment, gross	3,085	3,635
Buildings Improvements and Leaseholds [Member]
Property, plant and equipment, gross	15,972	18,745
Machinery, Equipment and Fixtures [Member]
Property, plant and equipment, gross	$ 76,906	$ 66,311

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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