Annual report pursuant to Section 13 and 15(d)

Note C - Shareholders' Equity (Details Textual)

v3.5.0.2
Note C - Shareholders' Equity (Details Textual) - USD ($)
3 Months Ended 9 Months Ended 12 Months Ended
Jun. 30, 2016
Dec. 31, 2015
Jun. 30, 2015
Dec. 31, 2014
Sep. 30, 2016
Sep. 30, 2016
Sep. 30, 2015
Sep. 30, 2014
Feb. 28, 2010
Maximum [Member] | Stock Compensation Plan 2007 [Member] | Restricted Stock [Member] | Employees [Member]                  
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period           10 years      
Maximum [Member] | Employee Stock Option [Member]                  
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period           5 years      
Maximum [Member]                  
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Remaining Contractual Term           6 years      
Minimum [Member] | Stock Compensation Plan 2007 [Member] | Restricted Stock [Member] | Employees [Member]                  
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period           1 year      
Minimum [Member] | Employee Stock Option [Member]                  
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period         3 years        
Employee Stock Purchase Plan [Member]                  
Share-based Compensation Arrangement by Share-based Payment Award, Purchase Price $ 11.40 $ 11.40 $ 10.46 $ 10.46          
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant         143,122 143,122      
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 11,966 10,352 10,119 10,097          
Payments Related to Tax Withholding for Share-based Compensation           $ 90,054      
Employee Stock Option [Member] | Director [Member]                  
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period           1 year      
Cashless Method Stock Option Exercised [Member]                  
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period           152,484 56,767    
Selling, General and Administrative Expenses [Member]                  
Allocated Share-based Compensation Expense           $ 1,272,656 $ 1,074,727 $ 794,865  
Cost of Sales [Member]                  
Allocated Share-based Compensation Expense           $ 132,243      
Director [Member]                  
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Remaining Contractual Term           6 years      
Preferred Stock, Shares Issued         0 0 0    
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 302 days 1 year 208 days    
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Exercisable, Number         0 0 59,090    
Preferred Stock, Shares Authorized         500 500 500    
Common Stock, Shares Authorized         50,000,000 50,000,000 50,000,000    
Common Stock, Par or Stated Value Per Share         $ 0.01 $ 0.01 $ 0.01    
Temporary Equity, Shares Subscribed but Unissued                 67,500
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant         95,848 95,848      
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized         $ 7,434,060 $ 7,434,060      
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition           8 years 36 days      
Allocated Share-based Compensation Expense           $ 1,404,899      
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested in Period, Fair Value             $ 373,271    
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Exercisable, Weighted Average Exercise Price             $ 6.32    
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period           (242,584) 73,167    
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value           $ 2,644,220 $ 876,841    
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value         $ 858,771 $ 858,771      
Stock Repurchased During Period, Shares           19,072 33,896    
Treasury Stock Acquired, Average Cost Per Share           $ 17.97 $ 16.89    
Payments Related to Tax Withholding for Share-based Compensation           $ 437,537 $ 639,307 $ 399,629