Note 3 - Property, Plant and Equipment - Summary of Property, Plant and Equipment (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020	Mar. 31, 2020
Property, plant and equipment, gross	$ 423,931		$ 367,310
Less: Accumulated Depreciation	(92,560)		(86,237)
Property, plant and equipment, net	331,371	$ 281,073	281,073
Refrigeration Equipment [Member]
Property, plant and equipment, gross	111,536		107,703
Machinery and Equipment [Member]
Property, plant and equipment, gross	115,613		106,176
Land, Buildings and Improvements [Member]
Property, plant and equipment, gross	103,850		101,786
Furniture and Office Equipment [Member]
Property, plant and equipment, gross	5,883		5,687
Leasehold Improvements [Member]
Property, plant and equipment, gross	1,314		1,301
Automotive Equipment [Member]
Property, plant and equipment, gross	65		160
Construction in Progress [Member]
Property, plant and equipment, gross	$ 85,671		$ 44,497

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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