Annual report pursuant to Section 13 and 15(d)

Stockholders' Equity (Stock Options Narrative) (Details)

v3.19.2
Stockholders' Equity (Stock Options Narrative) (Details) - USD ($)
1 Months Ended 9 Months Ended 12 Months Ended
May 13, 2019
Dec. 13, 2018
Sep. 06, 2018
Jul. 19, 2018
Apr. 05, 2018
Feb. 12, 2018
Jan. 04, 2018
Aug. 21, 2017
Jun. 11, 2017
May 13, 2017
Apr. 29, 2015
Jun. 18, 2019
Apr. 30, 2019
Dec. 24, 2018
Jan. 17, 2018
May 31, 2017
Apr. 30, 2019
Apr. 30, 2019
Apr. 30, 2018
Mar. 13, 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                                        
Unrecognized compensation cost                         $ 1,917,367       $ 1,917,367 $ 1,917,367    
Weighted average recognition period                                   2 years 6 months    
Proceeds from issuance of stock                     $ 101,502                  
Stock-based compensation                                   $ 1,190,385 $ 642,566  
Employee Stock Option [Member]                                        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                                        
Stock-based compensation                                 $ 1,190,384      
Restricted Stock [Member]                                        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                                        
Equity Incentive Plan, available shares remaining for issuance                           24,672            
Vesting period                           36 months            
Common Stock [Member]                                        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                                        
Share issued                                     113,597  
Proceeds from issuance of stock                                     $ 455,387  
Common stock issued for stock options exercised for cash, shares                                   56,910 136,563  
Share issued in exercise of stock options                                   56,910 136,563  
Stock-based compensation                                    
2012 Equity Incentive Plan [Member]                                        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                                        
Equity Incentive Plan, shares authorized   500,000                                   3,500,000
Equity Incentive Plan, available shares remaining for issuance                         322,712       322,712 322,712    
Shares remaining available for future issuance                         8,000       8,000 8,000    
Employees [Member]                                        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                                        
Options granted         19,000 31,000   52,250             74,000 5,500        
Options granted, exercise price         $ 7.31 $ 7.31   $ 5.95             $ 8.57          
Fair value of stock options granted         $ 33,250 $ 54,250   $ 89,348             $ 149,480          
Employees [Member] | Maximum [Member]                                        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                                        
Options granted, exercise price                               $ 5.10        
Employees [Member] | Minimum [Member]                                        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                                        
Options granted, exercise price                               $ 4.95        
Board of directors [Member]                                        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                                        
Options granted       560,000     180,000                          
Options granted, exercise price             $ 9.07                          
Weighted average grant-date fair value of stock options granted       $ 2.56                                
Weighted average recognition period       5 years                                
Fair value of stock options granted       $ 1,433,600     $ 421,200                          
CAO [Member]                                        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                                        
Options granted       180,000         30,000 70,000                    
Options granted, exercise price       $ 7.55         $ 6.28                      
Vesting period                 3 years                      
Weighted average recognition period       5 years         5 years                      
Fair value of stock options granted                 $ 54,000 $ 98,700                    
COO [Member]                                        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                                        
Options granted       180,000           200,000                    
Options granted, exercise price       $ 7.55                                
Weighted average recognition period       5 years                                
Fair value of stock options granted                   $ 282,000                    
CFO [Member]                                        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                                        
Options granted     180,000             30,000                    
Weighted average recognition period     5 years                                  
Fair value of stock options granted     $ 71,500             $ 42,300                    
Options term     33 months                                  
CFO [Member] | Restricted Stock [Member]                                        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                                        
Vesting period     36 months                                  
Weighted average recognition period     36 months                                  
Restricted shares granted     25,000                                  
Chairman and Chief Executive Officer [Member]                                        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                                        
Options granted       200,000           200,000                    
Options granted, exercise price       $ 7.55                                
Weighted average recognition period       5 years                                
Fair value of stock options granted                   $ 282,000                    
Executive officers [Member] | 2012 Equity Incentive Plan [Member]                                        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                                        
Options granted                   500,000                    
Options granted, exercise price                   $ 4.90                    
Vesting period                   3 years                    
Weighted average recognition period                   5 years                    
61 Employee [Member]                                        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                                        
Options granted   67,000                                    
Weighted average grant-date fair value of stock options granted   $ 5.20                                    
Fair value of stock options granted   $ 136,000                                    
Options term   36 months                                    
Three Directors [Member]                                        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                                        
Options granted                           61,667            
Weighted average grant-date fair value of stock options granted                           $ 5.1445            
Director One[Member]                                        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                                        
Options granted                           41,667            
Weighted average grant-date fair value of stock options granted                           $ 5.1445            
Two Other Director [Member]                                        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                                        
Options granted                           10,000            
Weighted average grant-date fair value of stock options granted                           $ 5.1445            
Director [Member]                                        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                                        
Fair value of stock options granted                           $ 123,000            
Options term                           36 months            
44 Employee [Member]                                        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                                        
Options granted                         65,750              
Weighted average grant-date fair value of stock options granted                         $ 4.56              
Fair value of stock options granted                         $ 117,000              
Chief Accounting Officer [Member]                                        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                                        
Options granted     50,000                                  
Weighted average recognition period     5 years                                  
Fair value of stock options granted     $ 257,400                                  
Options term     33 months                                  
Former Directors One [Member] | Subsequent Event [Member]                                        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                                        
Options granted 10,000                                      
Weighted average grant-date fair value of stock options granted $ 4.12                                      
Former Directors One [Member] | Restricted Stock [Member] | Subsequent Event [Member]                                        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                                        
Restricted shares granted                       5,131                
Former Directors Two [Member] | Subsequent Event [Member]                                        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                                        
Options granted 10,000                                      
Weighted average grant-date fair value of stock options granted $ 4.12                                      
Former Directors Two [Member] | Restricted Stock [Member] | Subsequent Event [Member]                                        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                                        
Restricted shares granted                       15,000                
Former Directors Three [Member] | Subsequent Event [Member]                                        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                                        
Options granted 10,000                                      
Weighted average grant-date fair value of stock options granted $ 4.12                                      
Former Directors Three [Member] | Restricted Stock [Member] | Subsequent Event [Member]                                        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                                        
Restricted shares granted                       10,000