v3.26.1
Note 10 - Equity Incentive Plans 1 (Details Textual) - USD ($)
 3 Months Ended 12 Months Ended
Mar. 31, 2026
Mar. 31, 2025
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Number (in shares) 27,767,619   25,407,299 20,405,239 17,938,726
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Weighted Average Exercise Price (in dollars per share) $ 1.62   $ 1.96 $ 2.49 $ 2.9
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Weighted-Average Remaining Contractual Term (Year) 7 years 4 months 24 days   7 years 3 months 10 days    
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Intrinsic Value $ 667,000   $ 4,000    
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Vested and Expected to Vest, Exercisable, Number (in shares) 13,614,279   14,808,497    
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Vested and Expected to Vest, Outstanding, Weighted Average Exercise Price (in dollars per share) $ 2.59   $ 2.84    
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Vested and Expected to Vest, Outstanding, Weighted Average Remaining Contractual Term (Year) 6 years 14 days   6 years 1 month 28 days    
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Vested and Expected to Vest, Outstanding, Aggregate Intrinsic Value $ 161,000   $ 4,000    
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercises in Period (in shares) (0) 3,625 3,625 38,030  
Proceeds from Stock Options Exercised $ 0 $ 3,000 $ 3,000 $ 30,000  
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercises in Period, Intrinsic Value   $ 0   $ 7,000  
Share Price (in dollars per share) $ 0.61 $ 0.85 $ 0.35    
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value (in dollars per share) $ 0.59 $ 0.46 $ 0.47 $ 1.01  
Share-Based Payment Arrangement, Nonvested Award, Option, Cost Not yet Recognized, Amount $ 12,100,000   $ 9,200,000    
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year) 3 years   2 years 4 months 24 days