Earnings Per Share - Computations of Basic and Diluted Earnings Per Share (Details) - USD ($)
12 Months Ended
Apr. 30, 2020
Apr. 30, 2019
Net earnings $ 2,788,605 $ 21,423,337
After-tax interest expense adjustment 37,414 279,950
Net earnings, if-converted basis $ 2,826,019 $ 21,703,287
Weighted average basic shares 131,472,281 80,487,890
Weighted average diluted shares 239,823,972 239,810,239
Earnings (loss) per share: Basic $ 0.02 $ 0.27
Earnings (loss) per share: Diluted $ 0.01 $ 0.09
Convertible Notes [Member]    
Weighted average diluted shares 39,993,730 63,195,608
Convertible Preferred Stock [Member]    
Weighted average diluted shares 46,125,389 90,914,381
Stock Options and Warrants [Member]    
Weighted average diluted shares 22,232,572 5,212,360