Quarterly report pursuant to Section 13 or 15(d)

Note 9 - Summary of Stock Options (Details Textual)

v3.8.0.1
Note 9 - Summary of Stock Options (Details Textual) - USD ($)
1 Months Ended 3 Months Ended 9 Months Ended 12 Months Ended
Dec. 23, 2016
Aug. 22, 2016
Sep. 30, 2017
Aug. 30, 2017
May 31, 2017
Jan. 31, 2017
Nov. 30, 2016
Sep. 30, 2016
Aug. 31, 2016
Jan. 31, 2016
Sep. 30, 2017
Sep. 30, 2016
Sep. 30, 2017
Sep. 30, 2016
Dec. 31, 2016
Aug. 15, 2017
Aug. 14, 2017
Dec. 22, 2016
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number     2,489,979               2,489,979   2,489,979   1,909,764      
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price     $ 5.88               $ 5.88   $ 5.88   $ 6.19      
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term                         8 years 255 days   9 years 43 days      
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross                         739,985          
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period                         7,730          
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value                         $ 31,000 $ 5,000        
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate                     0.00% 0.00% 0.00% 0.00%        
Employee Service Share-based Compensation, Nonvested Awards, Compensation Not yet Recognized, Stock Options     $ 4,400,000               $ 4,400,000   $ 4,400,000          
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition                         2 years 313 days          
Employee Stock Option [Member]                                    
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate                         0.00%          
Two Thousand Five Plan [Member]                                    
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number     0               0   0          
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant     0               0   0          
The 2006 Stock Option Plan [Member]                                    
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number     38,378               38,378   38,378          
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price     $ 10.49               $ 10.49   $ 10.49          
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term                         5 years 47 days          
The 2013 Plan [Member]                                    
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number     2,451,601               2,451,601   2,451,601          
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price     $ 5.80               $ 5.80   $ 5.80          
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term                         8 years 277 days          
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period                         10 years          
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period                         4 years          
Share-based Compensation Arrangement by Share-based Payment Award, Percentage of Outstanding Stock Maximum                         10.00%          
Share-based Compensation Arrangement by Share-based Payment Award, Purchase Price of Common Stock, Percent                         110.00%          
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized, Percentage Increase of Outstanding Common Stock   4.00%                                
Share-based Compensation Arrangement by Share-based Payment Award, Number of Additional Shares Authorized 523,209                                  
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized 2,523,209                             4,000,000 2,523,209 2,000,000
Common Stock, Capital Shares Reserved for Future Issuance     1,408,655               1,408,655   1,408,655          
The 2013 Plan [Member] | Employees [Member]                                    
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross                     305,000 220,915 720,110 378,932        
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value                     $ 3.19 $ 3.58 $ 2.83 $ 3.54        
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period                         7,730 3,020        
The 2013 Plan [Member] | Nonemployees [Member]                                    
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross                     14,000 50,000 19,875 50,000        
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value                     $ 3.66 $ 4.81 $ 4.09 $ 4.81        
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period                         0 0        
The 2013 Plan [Member] | Restricted Stock [Member]                                    
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number     0               0   0          
The 2013 Plan [Member] | Restricted Stock [Member] | Employees [Member]                                    
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period                   39,494                
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value                   $ 6.24                
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period               89                    
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period           39,405                        
The 2013 Plan [Member] | Restricted Stock [Member] | Board Members [Member]                                    
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period     6,947   4,797   6,544   5,998                  
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value     $ 5.58   $ 7.07   $ 5.91   $ 7.89                  
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period     6,947   4,797   6,544   5,998                  
The 2013 Plan [Member] | Restricted Stock [Member] | Consultant [Member]                                    
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period               1 year                    
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period               25,000                    
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value               $ 7.58                    
The 2013 Plan [Member] | Holdings Greater Than 10 Percent of Shares Outstanding [Member]                                    
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period                         5 years          
The 2013 Plan [Member] | Quarterly [Member] | Restricted Stock [Member] | Consultant [Member]                                    
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period                         25,000          
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage               25.00%                    
2017 Employee Stock Purchase Plan [Member]                                    
Common Stock, Capital Shares Reserved for Future Issuance       400,000                            
Share-based Compensation Arrangement by Share-based Payment Award, Maximum Number of Shares Per Employee       2,000                            
Share-based Compensation Arrangement by Share-based Payment Award, Discount from Market Price, Offering Date       85.00%                            
Share-based Compensation Arrangement by Share-based Payment Award, Offering Period       90 days