Note 5 - Property, Plant and Equipment - Property, Plant and Equipment (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Mar. 31, 2022	Jan. 01, 2022
Property, Plant and Equipment, Gross	$ 739,516	$ 688,596	$ 673,709
Less: accumulated depreciation	(441,840)	(420,553)	(415,505)
Property, plant and equipment, net	297,676	268,043	258,204
Land and Land Improvements [Member]
Property, Plant and Equipment, Gross	46,832	42,981	42,889
Building and Building Improvements [Member]
Property, Plant and Equipment, Gross	210,991	202,444	197,080
Machinery and Equipment [Member]
Property, Plant and Equipment, Gross	423,901	403,192	390,344
Office Furniture, Vehicles and Computer Software [Member]
Property, Plant and Equipment, Gross	11,397	10,003	10,018
Construction in Progress [Member]
Property, Plant and Equipment, Gross	$ 46,395	$ 29,976	$ 33,378

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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