Quarterly report pursuant to Section 13 or 15(d)

Note 4 - Stock-based Compensation (Details Textual)

v3.20.2
Note 4 - Stock-based Compensation (Details Textual) - USD ($)
3 Months Ended 9 Months Ended
Jun. 01, 2016
Sep. 30, 2020
Jun. 30, 2020
Mar. 31, 2020
Sep. 30, 2019
Sep. 30, 2020
Sep. 30, 2019
Dec. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number, Ending Balance (in shares)   1,430,000 1,220,000 1,220,000   1,430,000   1,349,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross (in shares)   210,000 10,000 0 220,000 3,000  
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period (in shares)   0 0 0 10,000  
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount, Total   $ 72,100       $ 72,100    
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Month)           180 days    
Share-based Payment Arrangement, Expense   $ 6,365     $ 585 $ 7,171 $ 5,521  
The 2016 Stock Incentive Plan [Member]                
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized (in shares) 1,000,000              
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period (Year) 10 years              
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number, Ending Balance (in shares)   591,000       591,000    
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Number (in shares)   369,500       369,500    
The 2006 Stock Incentive Plan [Member]                
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized (in shares)   1,950,000       1,950,000    
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period (Year)           10 years    
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Number (in shares)   839,000       839,000    
Minimum [Member] | Share-based Payment Arrangement, Option [Member]                
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Month)           180 days    
Maximum [Member] | Share-based Payment Arrangement, Option [Member]                
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Month)           2 years