Annual report pursuant to Section 13 and 15(d)

Stockholders' Equity - Schedule of All Options and Exercisable Options (Details)

v3.21.2
Stockholders' Equity - Schedule of All Options and Exercisable Options (Details) - $ / shares
12 Months Ended
Apr. 30, 2021
Apr. 30, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
ALL OPTIONS, Outstanding No. of Options 1,214,473  
EXERCISABLE OPTIONS, Exercisable No. of Options 1,032,411 2,734,899
$2.28 to $2.76    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
ALL OPTIONS, Exercise Price Lower Range $ 2.28  
ALL OPTIONS, Exercise Price Upper Range 2.76  
ALL OPTIONS, Weighted Average Exercise Price $ 2.76  
ALL OPTIONS, Outstanding No. of Options 10,423  
EXERCISABLE OPTIONS, Weighted Average Exercise Price $ 2.76  
EXERCISABLE OPTIONS, Weighted Average Remaining Life In Years 5 months 1 day  
EXERCISABLE OPTIONS, Exercisable No. of Options 10,423  
$3.24 to $4.38    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
ALL OPTIONS, Exercise Price Lower Range $ 3.24  
ALL OPTIONS, Exercise Price Upper Range 4.38  
ALL OPTIONS, Weighted Average Exercise Price $ 3.82  
ALL OPTIONS, Outstanding No. of Options 184,222  
EXERCISABLE OPTIONS, Weighted Average Exercise Price $ 3.75  
EXERCISABLE OPTIONS, Weighted Average Remaining Life In Years 1 year 25 days  
EXERCISABLE OPTIONS, Exercisable No. of Options 144,387  
$4.50 to $5.20    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
ALL OPTIONS, Exercise Price Lower Range $ 4.50  
ALL OPTIONS, Exercise Price Upper Range 5.20  
ALL OPTIONS, Weighted Average Exercise Price $ 4.94  
ALL OPTIONS, Outstanding No. of Options 360,654  
EXERCISABLE OPTIONS, Weighted Average Exercise Price $ 4.93  
EXERCISABLE OPTIONS, Weighted Average Remaining Life In Years 1 year 7 months 28 days  
EXERCISABLE OPTIONS, Exercisable No. of Options 316,427  
$5.95 to $6.28    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
ALL OPTIONS, Exercise Price Lower Range $ 5.95  
ALL OPTIONS, Exercise Price Upper Range 6.28  
ALL OPTIONS, Weighted Average Exercise Price $ 6.10  
ALL OPTIONS, Outstanding No. of Options 58,000  
EXERCISABLE OPTIONS, Weighted Average Exercise Price $ 6.12  
EXERCISABLE OPTIONS, Weighted Average Remaining Life In Years 1 year 2 months 15 days  
EXERCISABLE OPTIONS, Exercisable No. of Options 58,000  
$7.17 to $7.55    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
ALL OPTIONS, Exercise Price Lower Range $ 7.17  
ALL OPTIONS, Exercise Price Upper Range 7.55  
ALL OPTIONS, Weighted Average Exercise Price $ 7.44  
ALL OPTIONS, Outstanding No. of Options 443,425  
EXERCISABLE OPTIONS, Weighted Average Exercise Price $ 7.42  
EXERCISABLE OPTIONS, Weighted Average Remaining Life In Years 2 years 4 months 9 days  
EXERCISABLE OPTIONS, Exercisable No. of Options 345,425  
$8.57 to $9.07    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
ALL OPTIONS, Exercise Price Lower Range $ 8.57  
ALL OPTIONS, Exercise Price Upper Range 9.07  
ALL OPTIONS, Weighted Average Exercise Price $ 8.98  
ALL OPTIONS, Outstanding No. of Options 157,749  
EXERCISABLE OPTIONS, Weighted Average Exercise Price $ 8.98  
EXERCISABLE OPTIONS, Weighted Average Remaining Life In Years 1 year 8 months 8 days  
EXERCISABLE OPTIONS, Exercisable No. of Options 157,749