Quarterly report pursuant to Section 13 or 15(d)

Stockholders' Equity - Narrative (Details)

v3.21.2
Stockholders' Equity - Narrative (Details)
3 Months Ended 6 Months Ended
Aug. 31, 2021
USD ($)
$ / shares
shares
Aug. 16, 2021
USD ($)
$ / shares
shares
Aug. 12, 2021
USD ($)
$ / shares
shares
Jul. 21, 2021
USD ($)
$ / shares
shares
Feb. 04, 2020
$ / shares
Apr. 10, 2019
USD ($)
$ / shares
shares
Oct. 31, 2021
USD ($)
plan
shares
Oct. 31, 2020
USD ($)
shares
Jul. 31, 2020
USD ($)
shares
Oct. 31, 2021
USD ($)
plan
$ / shares
shares
Oct. 31, 2020
USD ($)
shares
Apr. 30, 2021
USD ($)
shares
Dec. 30, 2020
shares
Dec. 29, 2020
shares
Nov. 05, 2018
USD ($)
$ / shares
shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                              
Number of stock-based incentive plans | plan             2     2          
Common stock, shares authorized (in shares) | shares             40,000,000     40,000,000   40,000,000      
Share price (in dollars per share) | $ / shares         $ 9.49                    
Amortization of deferred financing costs | $                   $ 19,643 $ 0        
Modification charge for warrants exercised | $                     25,966        
Common stock issued for stock options exercised for cash | $             $ 33,486 $ 945,332   56,034 2,215,315        
Unrecognized compensation costs | $             28,670     28,670          
Stock based compensation expense | $             $ 722,158 $ 1,831,548   $ 1,264,870 $ 2,318,658        
Treasury stock (in shares) | shares             155,486     155,486   155,486      
Treasury stock, value | $             $ 1,817,414     $ 1,817,414   $ 1,817,414      
Common Stock                              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                              
Common stock issued for stock options exercised for cash (in shares) | shares             11,655 502,412   16,752 917,587        
Common stock issued for cashless stock options exercised (in shares) | shares             30,156 22,339   30,156 22,339        
Common stock issued for cashless stock options exercised, retained by company (in shares) | shares                   169,844          
Common stock issued for stock options exercised for cash | $             $ 12 $ 502   $ 17 $ 918        
Revolving Credit Facility | Credit Facility Agreement                              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                              
Line of credit, maximum borrowing capacity | $ $ 5,000,000                           $ 5,000,000
Cooperman Warrants                              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                              
Number of securities called by warrants or rights (in shares) | shares                 192,049            
Modification charge for warrants exercised | $                 $ 25,966            
Restricted Stock                              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                              
Unvested shares of restricted common stock outstanding (in shares) | shares             8,224     8,224   8,224      
Total unrecognized compensation expense | $             $ 7,018     $ 7,018          
Weighted average recognition period                   2 months 1 day          
Stock based compensation expense | $             $ 10,525 10,529   $ 21,052 21,053        
Restricted Stock Units (RSUs)                              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                              
Unvested shares of restricted common stock outstanding (in shares) | shares             899,103     899,103   549,972      
Total unrecognized compensation expense | $             $ 4,839,604     $ 4,839,604          
Weighted average recognition period                   1 year 6 months 25 days          
Restricted shares granted (in shares) | shares                   412,792          
Fair value of RSUs | $     $ 1,000,000                        
Share price (in dollars per share) | $ / shares     $ 6.48                        
Amortization expense | $             112,155 111,211   $ 224,311 1,500,000        
Stock based compensation expense | $             $ 688,129 1,678,622   $ 1,134,906 1,986,474        
Restricted Stock Units (RSUs) | Share-based Payment Arrangement, Employee                              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                              
Restricted shares granted (in shares) | shares                   410,000          
Restricted Stock Units (RSUs) | Share-based Payment Arrangement, Tranche Three                              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                              
Unvested shares of restricted common stock outstanding (in shares) | shares             195,000     195,000          
Weighted average recognition period         4 years                    
Minimum closing price of common stock (in dollars per share) | $ / shares         $ 12                    
Consecutive trading days         20 days                    
Restricted Stock Units (RSUs) | Chief Financial Officer                              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                              
Restricted shares granted (in shares) | shares   125,000                          
Fair value of RSUs | $   $ 725,000                          
Share price (in dollars per share) | $ / shares   $ 5.80                          
Restricted Stock Units (RSUs) | Chief Operating Officer                              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                              
Restricted shares granted (in shares) | shares     80,000                        
Restricted Stock Units (RSUs) | Chief Academic Officer                              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                              
Restricted shares granted (in shares) | shares     80,000                        
Restricted Stock Units (RSUs) | Chief Executive Officer                              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                              
Restricted shares granted (in shares) | shares       125,000                      
Fair value of RSUs | $       $ 873,750                      
Share price (in dollars per share) | $ / shares       $ 6.99                      
Amortization expense | $             $ 72,813     $ 218,438          
Amortization period of expense       1 year                      
Expiration period of award       3 years                      
Restricted Stock Units (RSUs) | Employees                              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                              
Restricted shares granted (in shares) | shares                   2,792          
Fair value of RSUs | $             16,456     $ 16,456          
Vesting period of award (in years)                   3 years          
Restricted Stock Units (RSUs) | Employees | Minimum                              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                              
Grant price of award (in dollars per share) | $ / shares                   $ 4.92          
Restricted Stock Units (RSUs) | Employees | Maximum                              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                              
Grant price of award (in dollars per share) | $ / shares                   $ 6.50          
Warrant                              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                              
Vesting period of warrant 5 years                            
Warrant | Revolving Credit Facility | Credit Facility Agreement                              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                              
Number of securities called by warrants or rights (in shares) | shares 50,000                           92,049
Exercise price of warrants (in dollars per share) | $ / shares $ 5.89                           $ 5.85
Fair value of warrants outstanding | $ $ 137,500                           $ 255,071
Vesting period of warrant 14 months                            
Warrant | Leon and Toby Cooperman Family Foundation                              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                              
Number of securities called by warrants or rights (in shares) | shares 50,000                            
Exercise price of warrants (in dollars per share) | $ / shares $ 5.85                            
Exercise period of warrant 5 years                            
Warrant | Former Board of Director                              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                              
Amortization expense | $             7,000     $ 9,333          
Number of securities called by warrants or rights (in shares) | shares       25,000                      
Exercise price of warrants (in dollars per share) | $ / shares       $ 6.99                      
Exercise period of warrant       5 years                      
Fair value of warrants outstanding | $       $ 84,000                      
Vesting period of warrant       3 years                      
Warrant | Director                              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                              
Amortization expense | $             9,125     $ 18,250          
Number of securities called by warrants or rights (in shares) | shares           50,000                  
Exercise price of warrants (in dollars per share) | $ / shares           $ 4.89                  
Exercise period of warrant           5 years                  
Fair value of warrants outstanding | $           $ 109,500                  
Vesting period of warrant           3 years                  
Stock Incentive Plan and Stock Option Grants to Employees and Directors                              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                              
Common stock issued for stock options exercised for cash (in shares) | shares                   216,752          
Common stock issued for stock options exercised (in shares) | shares                   46,908          
Stock Incentive Plan and Stock Option Grants to Employees and Directors | Chief Operating Officer                              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                              
Common stock issued for stock options exercised for cash (in shares) | shares                   200,000          
Stock options                              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                              
Weighted average recognition period                   11 months 1 day          
Stock based compensation expense | $             $ 23,504 $ 142,397   $ 108,912 $ 311,131        
2018 Equity Incentive Plan                              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                              
Common stock, shares authorized (in shares) | shares                         1,600,000 1,100,000  
Common stock, shares remaining for future issuance (in shares) | shares             549,739     549,739   549,739      
2018 Equity Incentive Plan | Restricted Stock Units (RSUs)                              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                              
Weighted average recognition period                   3 years          
Amortization expense | $             $ 146,817                
Equity Incentive Plan                              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                              
Common stock, shares remaining for future issuance (in shares) | shares             171,459     171,459   171,459