Note 3 - Net Income Per Common Share - Computation of Basic and Diluted Net Income Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands |
3 Months Ended | 9 Months Ended | ||
|---|---|---|---|---|
Sep. 30, 2016 |
Sep. 30, 2015 |
Sep. 30, 2016 |
Sep. 30, 2015 |
|
| Net income | $ 11,982 | $ 12,382 | $ 33,335 | $ 34,521 |
| Basic - weighted-average shares outstanding: (in shares) | 26,416,041 | 26,083,405 | 26,334,738 | 25,952,451 |
| Effect of dilutive securities: | ||||
| Employee stock options and other (in shares) | 193,837 | 297,908 | 204,340 | 338,307 |
| Diluted - weighted-average shares outstanding: (in shares) | 26,609,878 | 26,381,313 | 26,539,078 | 26,290,758 |
| Net income per share: | ||||
| Basic (in dollars per share) | $ 0.45 | $ 0.47 | $ 1.27 | $ 1.33 |
| Diluted (in dollars per share) | $ 0.45 | $ 0.47 | $ 1.26 | $ 1.31 |