Note 7 - Property, Plant and Equipment - Schedule of Property, Plant and Equipment (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Property Plant And Equipment [Line Items]
Property, Plant, and Equipment, Gross	$ 739,643	$ 625,108
Accumulated depreciation	(379,115)	(370,809)
Net	360,528	254,299
Land [Member]
Property Plant And Equipment [Line Items]
Property, Plant, and Equipment, Gross	18,790	6,911
Building and Building Improvements [Member]
Property Plant And Equipment [Line Items]
Property, Plant, and Equipment, Gross	177,568	129,065
Machinery and Equipment [Member]
Property Plant And Equipment [Line Items]
Property, Plant, and Equipment, Gross	489,980	451,882
Furniture and Fixtures [Member]
Property Plant And Equipment [Line Items]
Property, Plant, and Equipment, Gross	3,094	2,850
Construction in Progress [Member]
Property Plant And Equipment [Line Items]
Property, Plant, and Equipment, Gross	$ 50,211	$ 34,400

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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