Quarterly report pursuant to Section 13 or 15(d)

Note 9 - Stockholders' Equity (Details Textual)

v3.20.2
Note 9 - Stockholders' Equity (Details Textual)
$ / shares in Units, xbrli-pure in Thousands
1 Months Ended 3 Months Ended 9 Months Ended
Jun. 30, 2020
USD ($)
$ / shares
shares
May 14, 2019
$ / shares
shares
Jun. 30, 2020
USD ($)
$ / shares
shares
Apr. 30, 2020
USD ($)
$ / shares
shares
Feb. 28, 2019
USD ($)
$ / shares
shares
May 31, 2014
USD ($)
$ / shares
shares
Sep. 30, 2019
USD ($)
$ / shares
shares
Sep. 30, 2020
USD ($)
$ / shares
shares
Sep. 30, 2019
USD ($)
$ / shares
shares
Dec. 31, 2019
$ / shares
shares
Dec. 17, 2019
shares
Jun. 30, 2019
$ / shares
Dec. 31, 2018
$ / shares
shares
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share) | $ / shares               $ 1.95   $ 0.50   $ 1.49 $ 2.55
Proceeds from Issuance of Private Placement | $         $ 250,000 $ 10,000,000   $ 250,000        
Share Price (in dollars per share) | $ / shares             $ 0.83   $ 0.83        
Proceeds from Issuance of Common Stock | $               $ 18,043,284 $ 1,974,547        
Deferred Compensation Arrangement with Individual, Shares Authorized for Issuance (in shares)             2,646,346 2,351,727 2,646,346 2,375,762     2,470,566
Class of Warrant or Right, Reclassified During Period (in shares)                 376,000        
Gain (Loss) on Issuance of Shares to be Issued | $             $ (680,542)   $ (674,792)        
Derivative Instruments Not Designated as Hedging Instruments, Gain | $             $ 1,200,000   $ 1,200,000        
Common Stock, Shares Authorized (in shares)               75,000,000   75,000,000 75,000,000    
Derivative, Number of Instruments Held, Total               0          
Common Stock, Shares, To be Issued (in shares)             2,600,000   2,600,000        
Chief Executive Officer, Chief Financial Officer and Employees [Member]                          
Deferred Compensation Arrangement with Individual, Shares Authorized for Issuance (in shares)             2,294,734 2,202,229 2,294,734        
Non-Employees [Member]                          
Common Stock, Capital Shares Reserved for Future Issuance (in shares)             351,612 149,498 351,612        
Preferred Stock Converted to Common Stock [Member]                          
Conversion of Stock, Conversion Price (in dollars per share) | $ / shares   $ 1.17                      
Conversion of Stock, Shares Issued (in shares)   5,982,906                      
Warrants, Public Offering [Member]                          
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares)         1,428,750                
Warrants and Rights Outstanding, Term (Year)         5 years                
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share) | $ / shares         $ 0.50                
Underwrite Warrants [Member]                          
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares)         141,850                
Warrants, Private Offering [Member]                          
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares)         178,571                
Warrants and Rights Outstanding, Term (Year)         5 years                
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share) | $ / shares         $ 0.50                
Warrants Associated With April 2020 Public Offering [Member]                          
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares)       2,710,000                  
Warrants and Rights Outstanding, Term (Year)       3 years                  
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share) | $ / shares       $ 1.20                  
Warrants Associated With the June 2020 Public Offering [Member]                          
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares) 3,749,000   3,749,000                    
Warrants and Rights Outstanding, Term (Year) 3 years   3 years                    
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share) | $ / shares $ 2.60   $ 2.60                    
Public Offering [Member]                          
Proceeds from Issuance or Sale of Equity, Total | $         $ 2,000,000                
Stock Issued During Period, Shares, New Issues (in shares)         5,715,000                
Proceeds from Stock Options Exercised | $         $ 198,000                
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period (in shares)         567,400                
Private Placement [Member]                          
Stock Issued During Period, Shares, New Issues (in shares)         714,286 2,000,000              
Proceeds from Issuance of Common Stock | $           $ 3,000,000              
Shares Issued, Price Per Share (in dollars per share) | $ / shares           $ 1.50              
Proceeds from Issuance of Convertible Preferred Stock | $           $ 7,000,000              
Private Placement [Member] | Series A Convertible Preferred Stock [Member]                          
Stock Issued During Period, Shares, New Issues (in shares)           7,000              
Shares Issued, Price Per Share (in dollars per share) | $ / shares           $ 1,000              
Preferred Stock, Redemption Price Per Share (in dollars per share) | $ / shares           2.545              
Private Placement [Member] | Series A Convertible Preferred Stock [Member] | Conversion Price if Common Stock Not Trade at 3.15 [Member]                          
Preferred Stock, Redemption Price Per Share (in dollars per share) | $ / shares           $ 1.50              
April 6, 2020 Public Offering [Member]                          
Stock Issued During Period, Shares, New Issues (in shares)       5,420,000                  
Proceeds from Issuance of Common Stock, Gross | $       $ 5,100,000                  
Share Price (in dollars per share) | $ / shares       $ 0.95                  
Proceeds from Issuance of Common Stock | $       $ 4,600,000                  
June 30, 2020 Public Offering [Member]                          
Stock Issued During Period, Shares, New Issues (in shares) 6,770,000                        
Proceeds from Issuance of Common Stock, Gross | $ $ 14,600,000                        
Share Price (in dollars per share) | $ / shares $ 2.15   $ 2.15                    
Proceeds from Issuance of Common Stock | $     $ 13,400,000