Property and Equipment (Details) - USD ($) $ in Thousands	Apr. 30, 2020	Apr. 30, 2019
Property, Plant and Equipment [Line Items]
Gross property plant and equipment	$ 33,332	$ 32,912
Accumulated depreciation and amortization	(29,959)	(29,327)
Net property plant and equipment	3,373	3,585
Buildings and leasehold improvements
Property, Plant and Equipment [Line Items]
Gross property plant and equipment	16,881	16,724
Computer equipment and purchased software
Property, Plant and Equipment [Line Items]
Gross property plant and equipment	11,478	11,235
Office furniture and equipment
Property, Plant and Equipment [Line Items]
Gross property plant and equipment	$ 4,973	$ 4,953

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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