Note 7 - Property, Plant and Equipment, Net - Property, Plant and Equipment (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Property, plant and equipment, gross	$ 149,087	$ 148,062
Accumulated depreciation	(111,518)	(109,852)
Property, plant and equipment, net	37,569	38,210
Land [Member]
Property, plant and equipment, gross	1,105	1,105
Building and Building Improvements [Member]
Property, plant and equipment, gross	21,469	20,915
Machinery and Equipment [Member]
Property, plant and equipment, gross	122,051	120,961
Construction in Progress [Member]
Property, plant and equipment, gross	$ 4,462	$ 5,081

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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