Note 3 - Accounts Receivable, Net, Contract Asset and Contract Liability (Details Textual) - USD ($) $ in Thousands	12 Months Ended
	Apr. 30, 2024	Apr. 30, 2023
Accounts Receivable, after Allowance for Credit Loss	$ 5,776	$ 3,793
Accounts Receivable, Allowance for Credit Loss	47	205
Contract with Customer, Asset, after Allowance for Credit Loss	3,812	1,893
Increase (Decrease) in Contract with Customer, Asset	1,919	423
Increase (Decrease) in Contract with Customer, Liability	(109)	5,211
Contract with Customer, Liability, Revenue Recognized	$ 4,323	$ 820