v3.23.2
Note 15 - Stock-based Compensation - Assumptions to Calculate Fair Value of Each Performance-based Stock Option (Details) - Performance Shares [Member]
12 Months Ended
Dec. 31, 2022
Dec. 31, 2021
Risk-free interest rate 0.00% 1.50%
Expected volatility 0.00% 90.00%
Expected dividend rate 0.00% 0.00%
Minimum [Member]    
Derived service period (in years) (Year)   2 years 3 months 18 days
Maximum [Member]    
Derived service period (in years) (Year)   2 years 7 months 6 days