Note 7 - Property, Plant and Equipment - Property, Plant and Equipment (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Property, plant and equipment, gross	$ 149,678	$ 168,377
Accumulated depreciation	(114,577)	(126,434)
Property, plant and equipment, net	35,101	41,943
Land [Member]
Property, plant and equipment, gross	1,104	1,431
Building and Building Improvements [Member]
Property, plant and equipment, gross	20,149	29,722
Machinery and Equipment [Member]
Property, plant and equipment, gross	126,156	132,134
Construction in Progress [Member]
Property, plant and equipment, gross	$ 2,269	$ 5,090

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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