Quarterly report pursuant to Section 13 or 15(d)

Summary of activity under the Plan (Details)

v3.22.2.2
Summary of activity under the Plan (Details) - Options 1 [Member] - USD ($)
3 Months Ended 12 Months Ended
Jul. 31, 2022
Jul. 31, 2021
Apr. 30, 2021
Apr. 30, 2022
Apr. 30, 2020
Share-Based Payment Arrangement, Option, Exercise Price Range [Line Items]          
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Number 3,634,142     3,694,142 2,197,475
Share-Based Payment Arrangement, Option, Exercise Price Range, Outstanding, Weighted Average Exercise Price $ 2.16     $ 2.17 $ 1.79
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term 8 years 3 months 21 days 8 years 6 months 21 days 8 years 8 months 4 days    
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Vested and Expected to Vest, Outstanding, Aggregate Intrinsic Value $ 1,608,791   $ 4,943,870 $ 1,407,545  
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Gross 1,681,000      
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value   $ 2.58      
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercises in Period (150,000)      
Share-Based Compensation Arrangements by Share-Based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price   $ 2.49      
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Nonvested Options Forfeited, Number of Shares (60,000) (34,333)      
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Forfeitures and Expirations in Period, Weighted Average Exercise Price $ 2.55 $ 2.11      
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercisable, Number 2,312,975        
Share-Based Payment Arrangement, Option, Exercise Price Range, Exercisable, Weighted Average Exercise Price $ 1.89        
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercisable, Weighted Average Remaining Contractual Term 7 years 8 months 4 days        
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Vested and Expected to Vest, Exercisable, Aggregate Intrinsic Value $ 1,334,291