Property and Equipment (Details) - USD ($) $ in Thousands	Apr. 30, 2019	May 01, 2018	Apr. 30, 2018
Property, Plant and Equipment [Line Items]
Gross property plant and equipment	$ 32,912		$ 31,678
Accumulated depreciation and amortization	(29,327)		(28,644)
Net property plant and equipment	3,585	$ 3,034	3,034
Buildings and leasehold improvements
Property, Plant and Equipment [Line Items]
Gross property plant and equipment	16,724		15,325
Computer equipment and purchased software
Property, Plant and Equipment [Line Items]
Gross property plant and equipment	11,235		11,692
Office furniture and equipment
Property, Plant and Equipment [Line Items]
Gross property plant and equipment	$ 4,953		$ 4,661

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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