v3.26.1
Note 9 - Equity Incentive Plan - Summary of Stock Option Activity (Details) - The 2017 Equity Award Plan [Member]
 6 Months Ended 12 Months Ended
Jun. 30, 2026
USD ($)
$ / shares
shares
Dec. 31, 2025
USD ($)
$ / shares
shares
Outstanding balance, number of shares subject to option (in shares) | shares 423,034  
Outstanding, weighted average exercise price (in dollars per share) | $ / shares $ 1.12  
Outstanding balance, weighted average remaining contractual term (Year) 2 years 5 months 12 days 2 years 7 months 17 days
Outstanding, aggregate intrinsic value | $ $ 0 $ 180,000
Exercised, number of shares subject to option (in shares) | shares (50,000)  
Exercised, weighted average exercise price (in dollars per share) | $ / shares $ 0.78  
Expired, number of shares subject to option (in shares) | shares (8,833)  
Expired, weighted average exercise price (in dollars per share) | $ / shares $ 0.8  
Outstanding balance, number of shares subject to option (in shares) | shares 364,201 423,034
Outstanding, weighted average exercise price (in dollars per share) | $ / shares $ 1.18 $ 1.12