Annual report pursuant to Section 13 and 15(d)

Note C - Shareholders' Equity (Details Textual)

v3.8.0.1
Note C - Shareholders' Equity (Details Textual) - USD ($)
3 Months Ended 12 Months Ended
Jun. 30, 2017
Dec. 31, 2016
Jun. 30, 2016
Dec. 31, 2015
Sep. 30, 2017
Sep. 30, 2016
Sep. 30, 2015
Feb. 28, 2010
Common Stock, Shares Authorized         50,000,000 50,000,000    
Common Stock, Par or Stated Value Per Share         $ 0.01 $ 0.01    
Preferred Stock, Shares Authorized         5,000,000      
Temporary Equity, Shares Subscribed but Unissued               67,500
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant         1,103,657      
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized         $ 5,208,269      
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition         7 years 36 days      
Allocated Share-based Compensation Expense         $ 2,319,975 $ 1,404,899 $ 1,074,727  
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross         0 0 0  
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Remaining Contractual Term         2 years 266 days 2 years 302 days    
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Exercisable, Number         0 0    
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period         15,850 242,584    
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value         $ 237,172 $ 2,644,220    
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value         $ 421,237      
Stock Repurchased During Period, Shares         75,445 19,072    
Treasury Stock Acquired, Average Cost Per Share         $ 12.63 $ 17.97    
Payments Related to Tax Withholding for Share-based Compensation         $ 952,832 $ 437,537 $ 639,307  
Director [Member]                
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Remaining Contractual Term         6 years      
Employee Stock Option [Member] | Director [Member]                
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period         1 year      
Employee Stock Option [Member] | Minimum [Member]                
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period         3 years      
Employee Stock Option [Member] | Maximum [Member]                
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period         5 years      
Cashless Method Stock Option Exercised [Member]                
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period         10,500 152,484    
Employee Stock Purchase Plan [Member]                
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant         117,255      
Share-based Compensation Arrangement by Share-based Payment Award, Purchase Price $ 11.22 $ 15.21 $ 11.40 $ 11.40        
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 14,723 11,144 11,966 10,352        
Payments Related to Tax Withholding for Share-based Compensation         $ 73,542      
Stock Compensation Plan 2007 [Member] | Restricted Stock [Member] | Minimum [Member] | Employees [Member]                
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period         1 year      
Stock Compensation Plan 2007 [Member] | Restricted Stock [Member] | Maximum [Member] | Employees [Member]                
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period           10 years    
Selling, General and Administrative Expenses [Member]                
Allocated Share-based Compensation Expense         $ 2,103,621 $ 1,272,656    
Cost of Sales [Member]                
Allocated Share-based Compensation Expense         $ 216,354 $ 132,243    
Series B Preferred Stock [Member]                
Preferred Stock, Shares Authorized         500,000 500,000    
Preferred Stock, Shares Issued         0 0    
Preferred Stock, Shares Outstanding         0 0