Annual report pursuant to Section 13 and 15(d)

Stockholders' Equity (Schedule of Warrants) (Details)

v3.19.2
Stockholders' Equity (Schedule of Warrants) (Details) - Warrant [Member] - USD ($)
12 Months Ended
Apr. 30, 2019
Apr. 30, 2018
Number of Shares    
Balance Outstanding, April 30, 2018 651,286  
Granted 342,049  
Exercised (262,183)  
Surrendered  
Expired  
Balance Outstanding, April 30, 2019 731,152 651,286
Exercisable, April 30, 2019 681,152  
Weighted Average Exercise Price    
Balance Outstanding, April 30, 2018 $ 3.80  
Granted 5.80  
Exercised  
Surrendered  
Expired  
Balance Outstanding, April 30, 2019 5.28 $ 3.80
Exercisable, April 30, 2019 $ 5.31  
Weighted Average Remaining Contractual Term    
Granted 4 years 9 months 11 days  
Balance Outstanding, April 30, 2019 3 years 3 months 15 days 2 years 4 months 24 days
Exercisable, April 30, 2019 3 years 2 months 1 day  
Aggregate Intrinsic Value    
Balance Outstanding, April 30, 2018 $ 2,581,450  
Balance Outstanding, April 30, 2019 413,296 $ 2,581,450
Exercisable, April 30, 2019 $ 413,296