v3.26.3
Note 15 - Concentration of Credit Risk (Details Textual) - USD ($)
Jul. 31, 2026
Apr. 30, 2026
Jul. 31, 2025
Cash, Uninsured Amount $ 2,263,000 $ 1,259,000  
Restricted cash 305,000   $ 305,000
Cash Securing a Letter of Credit Issued as Security Deposit [Member] | Closing of Signature Bank [Member]      
Restricted cash $ 305,000