Quarterly report pursuant to Section 13 or 15(d)

Note 4 - Stock-based Compensation (Details Textual)

v3.21.1
Note 4 - Stock-based Compensation (Details Textual) - USD ($)
3 Months Ended
Mar. 31, 2021
Mar. 31, 2020
Share-based Payment Arrangement, Expense $ 121,000 $ 39,000
Share-based Payment Arrangement, Expense, Tax Benefit $ 0 $ 0
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value (in dollars per share) $ 1.87  
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate, Maximum 90.14%  
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate 0.67%  
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term (Year) 5 years 354 days  
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount, Total $ 595,000  
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year) 1 year 219 days