Note 9 - Property and Equipment - Components of Property and Equipment (Details) - USD ($)	Jul. 31, 2020	Apr. 30, 2020	May 01, 2019
Building and leasehold improvements	$ 1,013,000	$ 1,013,000
Operating lease - right-of-use asset	8,298,000	8,550,000	$ 9,575,000
Furniture and equipment	4,054,000	4,047,000
Property, Plant and Equipment, Gross, Ending Balance	13,365,000	13,610,000
Accumulated depreciation and amortization	(4,159,000)	(4,110,000)
Total property and equipment, net	$ 9,206,000	$ 9,500,000

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 equipment commonly used in offices and stores that have no permanent connection to the structure of a building or utilities. Examples include, but are not limited to, desks, chairs, tables, and bookcases.

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Amount of lessee's right to use underlying asset under operating lease.

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