Note 8 - Property, Plant & Equipment - Property, Plant and Equipment (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Property, plant and equipment, gross	$ 369,846	$ 360,975
Less accumulated depreciation and amortization	(161,307)	(142,434)
Property, plant and equipment, net before construction in progress and land	208,539	218,541
Property, plant and equipment, net	242,452	252,984
Land Improvements [Member]
Property, plant and equipment, gross	806	806
Building and Building Improvements [Member]
Property, plant and equipment, gross	89,061	88,280
Machinery and Equipment [Member]
Property, plant and equipment, gross	261,041	253,738
Furniture and Fixtures [Member]
Property, plant and equipment, gross	5,617	5,540
Computer Equipment and Software [Member]
Property, plant and equipment, gross	12,612	11,912
Vehicles [Member]
Property, plant and equipment, gross	709	699
Construction in Progress [Member]
Property, plant and equipment, net	32,812	33,342
Land [Member]
Property, plant and equipment, net	$ 1,101	$ 1,101