Annual report pursuant to Section 13 and 15(d)

Note 9 - Stock-based Compensation - Stock Option Transactions (Details)

v3.19.1
Note 9 - Stock-based Compensation - Stock Option Transactions (Details) - USD ($)
$ / shares in Units, shares in Thousands
12 Months Ended
Dec. 31, 2018
Dec. 31, 2017
Outstanding (in shares) 2,344 2,005
Outstanding, weighted average exercise price (in dollars per share) $ 3.46 $ 4.31
Granted (in shares) 2,320 826
Granted, weighted average exercise price (in dollars per share) $ 2.98 $ 1.19
Expired (in shares) (51) (323)
Expired, weighted average exercise price (in dollars per share) $ 2.34 $ 4.58
Forfeited (in shares) (10) (164)
Forfeited, weighted average exercise price (in dollars per share) $ 4.97 $ 3.35
Exercised (in shares) (114)  
Exercised, weighted average exercise price (in dollars per share) $ 2.04  
Outstanding (in shares) 4,489 2,344
Outstanding, weighted average exercise price (in dollars per share) $ 3.11 $ 3.46
Outstanding, weighted average remaining contractual life (Year) 7 years 328 days  
Outstanding, aggregate intrinsic value $ 562,438  
Exercisable (in shares) 2,544  
Exercisable, weighted average exercise price (in dollars per share) $ 3.41  
Exercisable, weighted average remaining contractual life (Year) 7 years 36 days  
Exercisable, aggregate intrinsic value $ 273,907  
Vested and expected to vest (in shares) 4,196  
Vested and expected to vest, weighted average exercise price (in dollars per share) $ 3.06  
Vested and expected to vest, weighted average remaining contractual life (Year) 7 years 292 days  
Vested and expected to vest, aggregate intrinsic value $ 519,159