Note 1 - Summary of Significant Accounting Policies - Summary of Property, Plant and Equipment (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Property, plant and equipment, gross	$ 306,696	$ 302,043
Less accumulated depreciation	(202,403)	(193,377)
Property, plant and equipment, net	104,293	108,666
Land [Member]
Property, plant and equipment, gross	5,813	5,805
Building [Member]
Property, plant and equipment, gross	112,760	111,876
Machinery and Equipment [Member]
Property, plant and equipment, gross	$ 188,123	$ 184,362