Annual report pursuant to Section 13 and 15(d)

Debt (Details)

v3.21.2
Debt (Details)
3 Months Ended 12 Months Ended
Sep. 14, 2020
USD ($)
$ / shares
shares
Sep. 14, 2020
USD ($)
d
$ / shares
Sep. 14, 2020
USD ($)
day
$ / shares
Jun. 05, 2020
$ / shares
shares
Jan. 22, 2020
USD ($)
lender
note
d
$ / shares
Mar. 06, 2019
USD ($)
agreement
$ / shares
shares
Nov. 08, 2018
$ / shares
shares
Nov. 05, 2018
USD ($)
$ / shares
shares
Feb. 29, 2012
USD ($)
$ / shares
Oct. 31, 2020
USD ($)
Apr. 30, 2020
USD ($)
Apr. 30, 2021
USD ($)
Apr. 30, 2020
USD ($)
Jun. 08, 2020
shares
Debt Instrument [Line Items]                            
Proceeds from issuance or sale of equity         $ 10,000,000                  
Beneficial conversion feature on Convertible Debt                       $ 0 $ 1,692,309  
Proceeds from convertible debt         16,000,000                  
Reverse stock split, conversion ratio                 0.08333          
Gain on extinguishment of debt                     $ 50,000 0 50,000  
Number of loan agreements | agreement           2                
Convertible Debt                            
Debt Instrument [Line Items]                            
Antidilutive securities excluded from computation of earnings per share, amount | shares 1,398,602                          
Cooperman Warrants                            
Debt Instrument [Line Items]                            
Class of warrant or right, number of securities called by warrants or rights (in shares) | shares                           192,049
Warrant | Cooperman Warrants                            
Debt Instrument [Line Items]                            
Common stock issued for warrants exercised for cash (in shares) | shares       100,000                    
Loans Payable                            
Debt Instrument [Line Items]                            
Write off of deferred debt issuance cost         182,000                  
Loan Agreements                            
Debt Instrument [Line Items]                            
Debt instrument, term           5 years                
Stock issued during period, shares, conversion of convertible securities | shares           100,000                
Warrants granted, exercise price (in dollars per share) | $ / shares           $ 6.00                
Warrants issued as part of senior secured term loans           $ 360,516                
Closing costs of senior secured loans           $ 33,693                
Loan Agreements | Cooperman Warrants                            
Debt Instrument [Line Items]                            
Warrants granted, exercise price (in dollars per share) | $ / shares       $ 5.70   $ 6.00                
Revolving Credit Facility                            
Debt Instrument [Line Items]                            
Line of credit facility, maximum borrowing capacity           $ 5,000,000                
Outstanding balance under facility               $ 0            
Leon and Toby Cooperman Family Foundation | Loan Agreements                            
Debt Instrument [Line Items]                            
Proceeds from issuance or sale of equity           $ 10,000,000                
Interest rate (as a percent)           12.00%                
Common stock short swing reclamation           $ 5,000,000                
One-time extension fee           1.00%                
Convertible Notes | Revolving Credit Facility                            
Debt Instrument [Line Items]                            
Line of credit facility, maximum borrowing capacity               5,000,000            
Beneficial conversion feature on Convertible Debt         1,692,309                  
Convertible Notes | Convertible Notes Payable                            
Debt Instrument [Line Items]                            
Proceeds from issuance or sale of equity         10,000,000                  
Face value of loan $ 10,000,000 $ 10,000,000 $ 10,000,000   $ 5,000,000                  
Number of lenders | lender         2                  
Number of notes | note         2                  
Conversion price after issuance date         6 months                  
Debt instrument, convertible, conversion price (in dollars per share) | $ / shares $ 7.15 $ 7.15 $ 7.15   $ 7.15                  
Average closing price of common stock (in dollars per share) | $ / shares $ 10.725 $ 10.725 $ 10.725   $ 10.725                  
Consecutive trading day period   20 20   20                  
Debt instrument, term         3 years                  
Interest rate (as a percent)         7.00%                  
Debt instrument, extension period         1 year                  
Extension fee per note         $ 50,000                  
Total extension fee         100,000                  
Payment to cover taxes         $ 40,400                  
Amortization expense                   $ 1,400,000        
Convertible note payable Dated February 29, 2012                            
Debt Instrument [Line Items]                            
Face value of loan                 $ 50,000          
2 Year Promissory Notes                            
Debt Instrument [Line Items]                            
Debt instrument, convertible, conversion price (in dollars per share) | $ / shares                 $ 12.00          
Debt instrument, term                 2 years          
Interest rate (as a percent)                 0.19%          
Credit Facility Agreement | Revolving Credit Facility                            
Debt Instrument [Line Items]                            
Line of credit facility, maximum borrowing capacity               $ 5,000,000            
Effective interest rate (as a percent)               12.00%            
Proceeds received from loan agreements               $ 100,000            
One-time extension fee (as a percent)               2.00%            
Outstanding balance under facility                     0 0 0  
Class of warrant or right, number of securities called by warrants or rights (in shares) | shares             92,049 92,049            
Warrant term             5 years 5 years            
Exercise price of warrants (in dollars per share) | $ / shares             $ 5.85 $ 5.85            
Warrants and rights outstanding               $ 255,071            
Unamortized costs                     $ 182,418 $ 18,056 $ 182,418  
Credit Facility Agreement | Revolving Credit Facility | Cooperman Warrants                            
Debt Instrument [Line Items]                            
Exercise price of warrants (in dollars per share) | $ / shares       $ 5.56       $ 5.85