Note 15 - 401(k) Profit Sharing Plan (Details Textual) $ in Thousands	12 Months Ended
	Apr. 30, 2023 USD ($)	Apr. 30, 2022 USD ($)
Number of Days of Service Eligible to Participate in Plan (Day)	30 days
Number of Entry Dates per Calendar Year to Participate in Plan	2
Defined Contribution Plan Matching Contribution, as Percent of Every Pretax Dollar	100.00%
Defined Contribution Plan, Employer Matching Contribution, Percent of Employees' Gross Pay	6.00%
Defined Contribution Plan, Employers Matching Contribution, Annual Vesting Percentage	100.00%
Defined Contribution Plan, Cost	$ 783	$ 807