v3.25.2
Note 10 - Stock-based Compensation Expense - Stock Option Activity (Details) - USD ($)
$ / shares in Units, $ in Thousands
 6 Months Ended 12 Months Ended
Jun. 30, 2025
Dec. 31, 2024
Balance, number of shares (in shares) 636,802  
Balance, weighted average exercise price (in dollars per share) $ 19.38  
Balance, weighted average remaining contractual term (Year) 7 years 8 months 12 days 7 years 7 months 6 days
Granted, number of shares (in shares) 375,400  
Granted, weighted average exercise price (in dollars per share) $ 3.63  
Expired, number of shares (in shares) (16,828)  
Expired, weighted average exercise price (in dollars per share) $ 60.14  
Outstanding, shares (in shares) 995,374 636,802
Outstanding, weighted average exercise price per share (in dollars per share) $ 12.75 $ 19.38
Outstanding, aggregate intrinsic value $ 0  
Exercisable, shares (in shares) 449,540  
Exercisable, weighted average exercise price per share (in dollars per share) $ 20.65  
Exercisable, weighted average remaining contractual term (Year) 6 years 7 months 6 days  
Exercisable, aggregate intrinsic value $ 0