Note 2 - Composition of Certain Financial Statement Captions - Summary of Property, Plant and Equipment (Details) - USD ($) $ in Thousands	Jan. 25, 2020	Apr. 27, 2019
Land	$ 9,835	$ 9,835
Buildings and improvements	58,747	58,291
Machinery and equipment	236,863	222,243
Total	305,445	290,369
Less accumulated depreciation	(189,674)	(179,053)
Property, plant and equipment – net	$ 115,771	$ 111,316

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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