Annual report pursuant to Section 13 and 15(d)

Stockholders' Equity - Warrants (Details)

v3.20.2
Stockholders' Equity - Warrants (Details)
12 Months Ended
Aug. 20, 2019
investor
shares
Aug. 17, 2019
shares
Apr. 30, 2019
shares
Mar. 05, 2019
shares
Nov. 08, 2018
$ / shares
shares
Nov. 05, 2018
$ / shares
shares
Jul. 19, 2018
shares
Apr. 30, 2020
shares
Apr. 30, 2019
USD ($)
shares
Jun. 07, 2019
shares
Jun. 03, 2019
shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                      
Cashless exercise of warrants (in shares)               164,929 218,323    
Common stock issued for cashless warrant exercise (in shares)               76,929 119,594    
Number of Investors | investor 2                    
Common stock, shares issued (in shares)     18,665,551         21,770,520 18,665,551    
Weighted average recognition period               1 year 8 months 12 days      
Common stock issued for stock options exercised for cash (in shares)               363,334 194,276    
Senior Loans                      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                      
Granted (in shares)       200,000              
Revolving Credit Facility | Credit Facility Agreement                      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                      
Class of warrant or right, number of securities called by warrants or rights (in shares)         92,049 92,049          
Warrant term         5 years 5 years          
Exercise price (in dollars per share) | $ / shares         $ 5.85 $ 5.85          
Warrant                      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                      
Common stock, shares issued (in shares)     119,594           119,594    
Common stock issued for stock options exercised for cash (in shares)                 262,183    
Exercises for cash (in shares)                 43,860    
Proceeds from issuance of warrants | $                 $ 100,000    
Warrant | Cashless Exercise of Stock Options                      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                      
Common stock issued for stock options exercised for cash (in shares)                 218,323    
Common Stock                      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                      
Common stock issued for stock options exercised for cash (in shares)               277,678 56,910    
Common Stock | Warrant Transaction Four                      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                      
Exercises for cash (in shares)                 43,860    
Investor                      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                      
Common stock issued for cashless warrant exercise (in shares)   6,271                  
Investor | Warrant                      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                      
Cashless exercise of warrants (in shares)   13,542                  
Investor 1                      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                      
Common stock issued for cashless warrant exercise (in shares) 8,970                    
Investor 1 | Warrant                      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                      
Cashless exercise of warrants (in shares) 18,818                    
Investor 2                      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                      
Common stock issued for cashless warrant exercise (in shares) 42,285                    
Investor 2 | Warrant                      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                      
Cashless exercise of warrants (in shares) 88,710                    
Former Director                      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                      
Common stock, shares issued (in shares)                     9,806
Former Director | Warrant                      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                      
Common stock, shares issued (in shares)                     21,930
Chief Executive Officer                      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                      
Common stock, shares issued (in shares)                   9,597  
Granted (in shares)             200,000        
Weighted average recognition period             5 years        
Advisory Board Member                      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                      
Granted (in shares)     50,000                
Weighted average recognition period     3 years