Annual report pursuant to Section 13 and 15(d)

Note D - Income Taxes (Details Textual)

v3.10.0.1
Note D - Income Taxes (Details Textual)
 3 Months Ended 12 Months Ended
Oct. 01, 2015
USD ($)
Sep. 30, 2018
USD ($)
Dec. 31, 2017
USD ($)
Sep. 30, 2016
USD ($)
Sep. 30, 2018
USD ($)
Sep. 30, 2017
USD ($)
Sep. 30, 2016
USD ($)
Sep. 30, 2015
USD ($)
Effective Income Tax Rate Reconciliation, Percent, Total         23.00% 31.00% 26.00%  
Accrued Income Taxes, Current   $ 464,000     $ 464,000      
Income Taxes Receivable, Current           $ 409,000    
Deferred Tax Assets, Valuation Allowance, Total   104,858   $ 322,404 104,858 159,154 $ 322,404 $ 658,808
Unrecognized Tax Benefits, Ending Balance   0   0 0   0  
Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense, Total         0 0 0  
State and Local Jurisdiction [Member]                
Operating Loss Carryforwards, Valuation Allowance, Total   105,000     105,000 $ 159,000    
Operating Loss Carryforwards, Total   3,468,000     3,468,000      
State and Local Jurisdiction [Member] | Research Tax Credit Carryforward [Member]                
Tax Credit Carryforward, Amount   198,000     198,000      
State and Local Jurisdiction [Member] | Alternative Minimum Tax [Member]                
Tax Credit Carryforward, Amount   50,000     50,000      
State and Local Jurisdiction [Member] | Research and Development and Alternative Minimum Tax Credit Carryforwards [Member]                
Deferred Tax Assets, Valuation Allowance, Total   0     0      
State and Local Jurisdiction [Member] | Deferred Tax Assets Related to Operating Loss Carryforwards [Member]                
Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount   $ (86,000) $ 32,000          
State and Local Jurisdiction [Member] | Valuation Allowance, Operating Loss Carryforwards, Expired and Utilized [Member]                
Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount         133,000      
State and Local Jurisdiction [Member] | Valuation Allowance, Operating Loss Carryforwards, Higher Expected NOL Utilization [Member]                
Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount         $ 47,000      
Adjustments for New Accounting Principle, Early Adoption [Member] | Accounting Standards Update 2016-09 [Member]                
Employee Service Share-based Compensation, Tax Benefit from Compensation Expense       $ 437,096     $ 675,183  
Effective Income Tax Rate Reconciliation, Percent, Total       16.30%     26.40%  
Increase (Decrease) in Earnings Per Share, Basic and Diluted             0.05  
Increase (Decrease) in Effective Income Tax Rate Reconciliation, Percent       13.70%     6.20%  
Increase (Decrease) in Earnings Per Share, Basic       0.03        
Increase (Decrease) in Earnings Per Share, Diluted       0.04        
Adjustments for New Accounting Principle, Early Adoption [Member] | December 31, 2015 [Member] | Accounting Standards Update 2016-09 [Member]                
Employee Service Share-based Compensation, Tax Benefit from Compensation Expense       $ 104,134        
Effective Income Tax Rate Reconciliation, Percent, Total       (5.20%)        
Increase (Decrease) in Earnings Per Share, Basic and Diluted       0.01        
Adjustments for New Accounting Principle, Early Adoption [Member] | March 31, 2016 [Member] | Accounting Standards Update 2016-09 [Member]                
Employee Service Share-based Compensation, Tax Benefit from Compensation Expense       $ 54,313        
Effective Income Tax Rate Reconciliation, Percent, Total       (2.50%)        
Increase (Decrease) in Earnings Per Share, Basic and Diluted       0        
Adjustments for New Accounting Principle, Early Adoption [Member] | June 30, 2016 [Member] | Accounting Standards Update 2016-09 [Member]                
Employee Service Share-based Compensation, Tax Benefit from Compensation Expense       $ 79,640        
Effective Income Tax Rate Reconciliation, Percent, Total       (2.30%)        
Increase (Decrease) in Earnings Per Share, Basic and Diluted       0.01        
Reclassification of Excess Tax Benefits Related to Stock-based Employee Awards from Financing Activities to Operating Activities [Member] | Accounting Standards Update 2016-09 [Member]                
Cumulative Effect on Retained Earnings, Net of Tax, Total $ 1,864,980              
Reclassification of Excess Tax Benefits Related to Stock-based Employee Awards from Financing Activities to Operating Activities [Member] | Three Months Ended December 31, 2015 [Member] | Accounting Standards Update 2016-09 [Member]                
Prior Period Reclassification Adjustment       $ 348,000        
Reclassification of Excess Tax Benefits Related to Stock-based Employee Awards from Financing Activities to Operating Activities [Member] | Six Months Ended March 31, 2016 [Member] | Accounting Standards Update 2016-09 [Member]                
Prior Period Reclassification Adjustment       741,000        
Reclassification of Excess Tax Benefits Related to Stock-based Employee Awards from Financing Activities to Operating Activities [Member] | Nine Months Ended June 30, 2016 [Member] | Accounting Standards Update 2016-09 [Member]                
Prior Period Reclassification Adjustment       $ 1,786,000