Property, Plant and Equipment, Net (Details) - Schedule of Property, Plant and Equipment - USD ($) $ in Thousands	Apr. 30, 2021	Apr. 30, 2020
Schedule of Property, Plant and Equipment [Abstract]
Buildings and building improvements	$ 2,721	$ 2,692
Machinery, equipment and furniture	59,136	57,916
	61,857	60,608
Less accumulated depreciation	(52,245)	(49,341)
	$ 9,612	$ 11,267

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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 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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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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