Note 9 - Property and Equipment - Components of Property and Equipment (Details) - USD ($)	Jan. 31, 2022	Apr. 30, 2021	May 01, 2019
Building and leasehold improvements	$ 1,013,000	$ 1,013,000
Operating lease - right-of-use asset	6,717,000	7,522,000	$ 9,575,000
Furniture and equipment	4,080,000	4,080,000
Property, Plant and Equipment, Gross, Ending Balance	11,810,000	12,615,000
Accumulated depreciation and amortization	(4,443,000)	(4,304,000)
Total property and equipment, net	$ 7,367,000	$ 8,311,000