Annual report pursuant to Section 13 and 15(d)

Debt - Narrative (Details)

v3.20.2
Debt - Narrative (Details)
1 Months Ended 3 Months Ended 12 Months Ended
Jan. 23, 2020
d
$ / shares
Jan. 22, 2020
USD ($)
note
lender
Mar. 06, 2019
USD ($)
$ / shares
shares
Feb. 25, 2019
USD ($)
Dec. 01, 2018
USD ($)
Nov. 08, 2018
$ / shares
shares
Nov. 05, 2018
USD ($)
$ / shares
shares
Nov. 05, 2018
USD ($)
$ / shares
shares
Dec. 02, 2017
USD ($)
$ / shares
Feb. 29, 2012
USD ($)
$ / shares
Mar. 31, 2019
USD ($)
Apr. 30, 2020
USD ($)
Apr. 30, 2020
USD ($)
Apr. 30, 2019
USD ($)
Debt Instrument [Line Items]                            
Beneficial conversion feature on convertible debt                         $ 1,692,309 $ 0
Proceeds from issuance or sale of equity   $ 10,000,000                        
Proceeds from convertible debt   16,000,000                        
Debt instrument, term                 2 years          
Interest rate (as a percent)                 8.00%          
Reverse stock split, conversion ratio                   0.08333        
Gain on debt extinguishment                       $ 50,000 50,000 0
Conversion of stock, amount converted                 $ 1,000,000          
Warrants issued as part of senior secured term loans                         0 360,516
Closing costs of senior secured loans                         0 $ 33,693
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                      
Loan Agreements | WarrantsMember                            
Debt Instrument [Line Items]                            
Warrants issued as part of senior secured term loans     $ 360,516                      
Closing costs of senior secured loans     33,693                      
Revolving Credit Facility                            
Debt Instrument [Line Items]                            
Line of credit facility, maximum borrowing capacity     5,000,000                      
Proceeds received from loan agreements                     $ 10,000,000      
One-time extension fee (as a percent)                     1.00%      
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 $ 5,000,000            
Beneficial conversion feature on convertible debt   1,692,309                        
Convertible Notes | Convertible Notes Payable                            
Debt Instrument [Line Items]                            
Face value of loan   $ 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                          
Average closing price of common stock (in dollars per share) | $ / shares $ 10.725                          
Consecutive trading day period | d 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                        
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        
Interest rate (as a percent)                   0.19%        
Convertible Debt                            
Debt Instrument [Line Items]                            
Debt instrument, periodic payment, principal       $ 1,000,000 $ 1,000,000                  
Debt instrument, periodic payment, interest       $ 80,000 $ 60,000                  
Convertible Debt | USU                            
Debt Instrument [Line Items]                            
Face value of loan                 $ 2,000,000          
Debt instrument, convertible, conversion price (in dollars per share) | $ / shares                 $ 2.00          
Credit Facility Agreement | Revolving Credit Facility                            
Debt Instrument [Line Items]                            
Line of credit facility, maximum borrowing capacity             $ 5,000,000 $ 5,000,000            
Effective interest rate (as a percent)             12.00% 12.00%            
Proceeds received from loan agreements               $ 100,000            
One-time extension fee (as a percent)               2.00%            
Class of warrant or right, number of securities called by warrants or rights (in shares) | shares           92,049 92,049 92,049            
Warrant term           5 years 5 years              
Exercise price of warrants (in dollars per share) | $ / shares           $ 5.85 $ 5.85 $ 5.85            
Warrants and rights outstanding             $ 255,071 $ 255,071            
Unamortized costs                       $ 182,418 $ 182,418