Annual report pursuant to Section 13 and 15(d)

Stockholders' Equity - Schedule of Fair Value Assumptions of Warrants (Details)

v3.21.2
Stockholders' Equity - Schedule of Fair Value Assumptions of Warrants (Details)
Apr. 30, 2021
$ / shares
Apr. 30, 2020
$ / shares
Apr. 02, 2020
$ / shares
Warrant exercise price     $ 7.00
Expected Volatility [Member]      
Warrant measurement input 169.0    
Stock Price on Date of Grant [Member]      
Warrant exercise price $ 9.53    
Exercise Price [Member]      
Warrant exercise price $ 6.00    
Expected Dividends [Member]      
Warrant measurement input 0    
Expected Term (in years) [Member]      
Warrant measurement term 5 years    
Risk-free Rate [Member]      
Warrant measurement input 0.27    
Expected Forfeiture Rate [Member]      
Warrant measurement input 0    
Class A Warrants [Member]      
Warrant exercise price $ 11.40    
Warrant measurement term 5 years    
Class A Warrants [Member] | Expected Volatility [Member] | Minimum [Member]      
Warrant measurement input   46  
Class A Warrants [Member] | Expected Volatility [Member] | Maximum [Member]      
Warrant measurement input   74  
Class A Warrants [Member] | Stock Price on Date of Grant [Member]      
Warrant exercise price   $ 11.40  
Class A Warrants [Member] | Exercise Price [Member]      
Warrant exercise price   $ 11.40  
Class A Warrants [Member] | Expected Dividends [Member]      
Warrant measurement input   0  
Class A Warrants [Member] | Expected Term (in years) [Member] | Minimum [Member]      
Warrant measurement term   6 months  
Class A Warrants [Member] | Expected Term (in years) [Member] | Maximum [Member]      
Warrant measurement term   5 years  
Class A Warrants [Member] | Risk-free Rate [Member] | Minimum [Member]      
Warrant measurement input   1.77  
Class A Warrants [Member] | Risk-free Rate [Member] | Maximum [Member]      
Warrant measurement input   2.11  
Class A Warrants [Member] | Expected Forfeiture Rate [Member]      
Warrant measurement input   0  
Common Warrants [Member] | Expected Volatility [Member]      
Warrant measurement input   133.0  
Common Warrants [Member] | Stock Price on Date of Grant [Member]      
Warrant exercise price   $ 5.34  
Common Warrants [Member] | Exercise Price [Member]      
Warrant exercise price   $ 7.00  
Common Warrants [Member] | Expected Dividends [Member]      
Warrant measurement input   0  
Common Warrants [Member] | Expected Term (in years) [Member]      
Warrant measurement term   5 years  
Common Warrants [Member] | Risk-free Rate [Member]      
Warrant measurement input   0.39  
Common Warrants [Member] | Expected Forfeiture Rate [Member]      
Warrant measurement input   0