XML 100 R83.htm IDEA: XBRL DOCUMENT v3.10.0.1
Note 13 - Stock Option Plans - Stock Option Transactions (Details) - $ / shares
12 Months Ended
Dec. 31, 2018
Dec. 31, 2017
Dec. 31, 2016
Outstanding, Number of shares (in shares) 653,571 474,501 513,366
Outstanding, Weighted average exercise price per share (in dollars per share) $ 36.69 $ 12.67 $ 9.24
Granted, Number of shares (in shares) 163,366 370,025 81,750
Granted, Weighted average exercise price per share (in dollars per share) $ 62.80 $ 54.10 $ 22.66
Exercised, Number of shares (in shares) (63,886) (172,759) (109,963)
Exercised, Weighted average exercise price per share (in dollars per share) $ 12.86 $ 7.88 $ 3.79
Forfeited, Number of shares (in shares) (50,714) (18,196) (9,902)
Forfeited, Weighted average exercise price per share (in dollars per share) $ 52.33 $ 37.70 $ 16.80
Expired, Number of shares (in shares) (750)
Expired, Weighted average exercise price per share (in dollars per share) $ 3.76
Outstanding, Number of shares (in shares) 702,337 653,571 474,501
Outstanding, Weighted average exercise price per share (in dollars per share) $ 43.80 $ 36.69 $ 12.67
Options exercisable, Number of shares (in shares) 326,937 243,771 332,192
Options exercisable, Weighted average exercise price per share (in dollars per share) $ 28.91 $ 14.79 $ 10.08