Quarterly report pursuant to Section 13 or 15(d)

Note 10 - Stock-based Compensation (Details Textual)

v3.19.3
Note 10 - Stock-based Compensation (Details Textual) - USD ($)
3 Months Ended 9 Months Ended 21 Months Ended
Sep. 30, 2019
Sep. 30, 2018
Sep. 30, 2019
Sep. 30, 2018
Sep. 30, 2019
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Intrinsic Value $ 11,817,136   $ 11,817,136   $ 11,817,136
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value 7,879,967   7,879,967   7,879,967
Share-based Payment Arrangement, Option [Member]          
Share-based Payment Arrangement, Expense 110,367 $ 62,951 307,017   271,764
Share-based Payment Arrangement, Nonvested Award, Option, Cost Not yet Recognized, Amount 840,547   $ 840,547   840,547
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition     2 years 255 days    
Restricted Stock [Member]          
Share-based Payment Arrangement, Expense 75,653 $ 59,825 $ 229,727 $ 197,641  
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition     2 years 36 days    
Share-based Payment Arrangement, Nonvested Award, Excluding Option, Cost Not yet Recognized, Amount $ 393,653   $ 393,653   $ 393,653