v3.25.4
Note 18 - Stock Options (Tables)
12 Months Ended
Dec. 31, 2025
Notes Tables  
Share-based Arrangement Plans, Approval and Available Shares [Table Text Block]
 

# Approved by

# Available

 # Approved byDecember 31,

Stockholder approved plan

Stockholders

2025

2012 Share Incentive Plan

 750,000 

2015 Executive and Employee Stock Option Plan

 2,000,000 

2017 Executive and Employee Stock Option Plan

 3,000,000 280,000

2019 Share Incentive Plan

 2,000,000 290,000

2021 Share Incentive Plan

 1,375,000 330,000

2023 Share Incentive Plan

 1,600,000 450,000
Share-Based Payment Arrangement, Option, Activity [Table Text Block]
      

Weighted average

 
  

Number of options

  

exercise price

 

Outstanding at December 31, 2023

  7,342,883  $6.31 

Granted

  1,587,929   2.26 

Exercised

  (569)  2.50 

Canceled and forfeited

  (1,291,785)  6.09 

Outstanding at December 31, 2024

  7,638,458  $5.50 

Granted

  1,858,000   1.38 

Exercised

  (275,143)  2.53 

Canceled and forfeited

  (1,641,938)  5.79 

Outstanding at December 31, 2025

  7,579,377  $4.54 
  

Number of options

  

Weighted average grant date fair value

 

Non-vested at December 31, 2024

  2,120,647  $2.49 

Granted

  1,858,000   1.09 

Vested

  (1,522,239)  2.54 

Forfeited

  (334,055)  1.59 

Non-vested at December 31, 2025

  2,122,353  $1.37 
Schedule of Share-Based Payment Award, Stock Options, Valuation Assumptions [Table Text Block]
  

2025 Grants

  

2024 Grants

 

Exercise price

 $0.90 - $1.85  

$1.02 - $2.42

 

Risk-free rate

  3.9% - 4.5%   3.9% - 4.2% 

Expected dividend yield

      

Expected volatility

  94.5% - 98.1%   92.1% - 95.1% 

Expected term (in years)

  6   6 

Grant date fair value

  $0.70 - $1.47   $0.80 - $1.87