Quarterly report pursuant to Section 13 or 15(d)

Note 4 - Stock-based Compensation (Details Textual)

v3.7.0.1
Note 4 - Stock-based Compensation (Details Textual) - USD ($)
3 Months Ended 9 Months Ended
Jun. 30, 2017
Dec. 31, 2016
Jun. 30, 2016
Jun. 30, 2017
Jun. 30, 2016
Allocated Share-based Compensation Expense $ 590,419   $ 370,465 $ 1,774,330 $ 843,658
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized 5,750,033     $ 5,750,033  
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition       7 years 109 days  
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period       15,850 172,450
Proceeds from Stock Options Exercised       $ 28,718 $ 473,651
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross       0 0
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term       3 years  
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Intrinsic Value $ 405,657     $ 405,657  
Employee Stock Purchase Plan [Member]          
Share-based Compensation Arrangement by Share-based Payment Award, Market Price Percentage, Offering Date       85.00%  
Stock Issued During Period, Shares, Employee Stock Purchase Plans   11,144   14,723  
Share-based Compensation Arrangement by Share-based Payment Award, Purchase Price   $ 15.21   $ 11.22  
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant 117,255     117,255  
Restricted Stock [Member]          
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period       3,795  
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value       $ 16.45  
Restricted Stock [Member] | Employee and Non-Employee Directors [Member] | Stock Compensation Plan 2007 [Member]          
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period       1 year 1 year
Restricted Stock [Member] | Non Employee Directors [Member] | Stock Compensation Plan 2007 [Member]          
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period       3,795 2,712
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value       $ 16.45 $ 14.73
Restricted Stock [Member] | Outgoing Non Employee Directors [Member] | Stock Compensation Plan 2007 [Member]          
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period         1,356
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value         $ 14.73
Restricted Stock [Member] | Employees [Member] | Stock Compensation Plan 2007 [Member]          
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period         259,555
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value         $ 17.43
Minimum [Member] | Restricted Stock [Member] | Employee and Non-Employee Directors [Member] | Stock Compensation Plan 2007 [Member]          
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period       1 year  
Minimum [Member] | Restricted Stock [Member] | Employees [Member] | Stock Compensation Plan 2007 [Member]          
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period         3 years
Maximum [Member] | Restricted Stock [Member] | Employee and Non-Employee Directors [Member] | Stock Compensation Plan 2007 [Member]          
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period       10 years  
Maximum [Member] | Restricted Stock [Member] | Employees [Member] | Stock Compensation Plan 2007 [Member]          
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period         5 years
Selling, General and Administrative Expenses [Member]          
Allocated Share-based Compensation Expense $ 535,719   336,310 $ 1,610,229 $ 765,347
Cost of Sales [Member]          
Allocated Share-based Compensation Expense $ 54,700   $ 34,155 $ 164,101 $ 78,311