Note 3 - Accounts Receivable, Net, Contract Asset and Contract Liability - Accounts Receivable, Net, Contract Asset and Contract Liability (Details) - USD ($) $ in Thousands	Apr. 30, 2023	Apr. 30, 2022
Accounts Receivable, net	$ 3,793	$ 3,636
Contract Asset	1,893	1,470
Contract Liability	$ 6,031	$ 820