Note 2 - Property, Plant and Equipment - Summary of Property, Plant and Equipment (Details) - USD ($) $ in Thousands	Jul. 31, 2021	May 01, 2021
Land	$ 9,835	$ 9,835
Buildings and improvements	62,785	62,346
Machinery and equipment	261,244	257,119
Total	333,864	329,300
Less accumulated depreciation	(201,947)	(198,273)
Property, plant and equipment – net	$ 131,917	$ 131,027

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 of building structures held for productive use including addition, improvement, or renovation to the structure, including, but not limited to, interior masonry, interior flooring, electrical, and plumbing.

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Amount before accumulated depletion of real estate held for productive use, excluding land held for sale.

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Amount before accumulated depreciation of tangible personal property used to produce goods and services, including, but is not limited to, tools, dies and molds, computer and office equipment.

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