Annual report pursuant to Section 13 and 15(d)

Note 10 - Summary of Stock Options - Summary of Options Outstanding and Exercisable (Details)

v3.19.1
Note 10 - Summary of Stock Options - Summary of Options Outstanding and Exercisable (Details)
12 Months Ended
Dec. 31, 2018
$ / shares
shares
Options outstanding, number (in shares) | shares 4,014,475
Options outstanding, weighted average exercise price (in dollars per share) $ 4.56
Options outstanding, weighted average remaining contractual term (Year) 7 years 146 days
Options exercisable, number exercisable (in shares) | shares 1,637,474
Options exercisable, weighted average exercise price (in dollars per share) $ 5.44
Range One [Member]  
Exercise price range, lower limit (in dollars per share) 1.75
Exercise price range, upper limit (in dollars per share) $ 1.97
Options outstanding, number (in shares) | shares 535,000
Options outstanding, weighted average exercise price (in dollars per share) $ 1.95
Options outstanding, weighted average remaining contractual term (Year) 9 years 146 days
Options exercisable, number exercisable (in shares) | shares 50,000
Options exercisable, weighted average exercise price (in dollars per share) $ 1.97
Range Two [Member]  
Exercise price range, lower limit (in dollars per share) 2.02
Exercise price range, upper limit (in dollars per share) $ 2.83
Options outstanding, number (in shares) | shares 180,000
Options outstanding, weighted average exercise price (in dollars per share) $ 2.40
Options outstanding, weighted average remaining contractual term (Year) 9 years 146 days
Options exercisable, number exercisable (in shares) | shares 11,459
Options exercisable, weighted average exercise price (in dollars per share) $ 1.97
Range Three [Member]  
Exercise price range, lower limit (in dollars per share) 3.03
Exercise price range, upper limit (in dollars per share) $ 3.82
Options outstanding, number (in shares) | shares 546,876
Options outstanding, weighted average exercise price (in dollars per share) $ 3.53
Options outstanding, weighted average remaining contractual term (Year) 9 years 36 days
Options exercisable, number exercisable (in shares) | shares 64,090
Options exercisable, weighted average exercise price (in dollars per share) $ 2.64
Range Four [Member]  
Exercise price range, lower limit (in dollars per share) 4.30
Exercise price range, upper limit (in dollars per share) $ 4.97
Options outstanding, number (in shares) | shares 1,247,318
Options outstanding, weighted average exercise price (in dollars per share) $ 4.54
Options outstanding, weighted average remaining contractual term (Year) 7 years 109 days
Options exercisable, number exercisable (in shares) | shares 503,934
Options exercisable, weighted average exercise price (in dollars per share) $ 3.76
Range Five [Member]  
Exercise price range, lower limit (in dollars per share) 5.01
Exercise price range, upper limit (in dollars per share) $ 5.67
Options outstanding, number (in shares) | shares 693,067
Options outstanding, weighted average exercise price (in dollars per share) $ 5.36
Options outstanding, weighted average remaining contractual term (Year) 6 years 292 days
Options exercisable, number exercisable (in shares) | shares 397,466
Options exercisable, weighted average exercise price (in dollars per share) $ 4.62
Range Six [Member]  
Exercise price range, lower limit (in dollars per share) 6
Exercise price range, upper limit (in dollars per share) $ 6.61
Options outstanding, number (in shares) | shares 490,470
Options outstanding, weighted average exercise price (in dollars per share) $ 6.04
Options outstanding, weighted average remaining contractual term (Year) 4 years 36 days
Options exercisable, number exercisable (in shares) | shares 412,662
Options exercisable, weighted average exercise price (in dollars per share) $ 5.34
Range Seven [Member]  
Exercise price range, lower limit (in dollars per share) 7
Exercise price range, upper limit (in dollars per share) $ 7.92
Options outstanding, number (in shares) | shares 283,599
Options outstanding, weighted average exercise price (in dollars per share) $ 7.65
Options outstanding, weighted average remaining contractual term (Year) 7 years 146 days
Options exercisable, number exercisable (in shares) | shares 159,718
Options exercisable, weighted average exercise price (in dollars per share) $ 6.02
Range Eight [Member]  
Exercise price range, lower limit (in dollars per share) 9.92
Exercise price range, upper limit (in dollars per share) $ 9.92
Options outstanding, number (in shares) | shares 38,135
Options outstanding, weighted average exercise price (in dollars per share) $ 9.92
Options outstanding, weighted average remaining contractual term (Year) 1 year 109 days
Options exercisable, number exercisable (in shares) | shares 38,135
Options exercisable, weighted average exercise price (in dollars per share) $ 7.66
Range Nine [Member]  
Exercise price range, lower limit (in dollars per share) 59.60
Exercise price range, upper limit (in dollars per share) $ 149.04
Options outstanding, number (in shares) | shares 10
Options outstanding, weighted average exercise price (in dollars per share) $ 149.04
Options outstanding, weighted average remaining contractual term (Year) 2 years 292 days
Options exercisable, number exercisable (in shares) | shares 10
Options exercisable, weighted average exercise price (in dollars per share) $ 9.92