Quarterly report pursuant to Section 13 or 15(d)

Net Income Per Share (Details)

v3.5.0.2
Net Income Per Share (Details) - USD ($)
$ / shares in Units, shares in Thousands, $ in Thousands
 3 Months Ended 6 Months Ended
Jun. 30, 2016
Jun. 30, 2015
Jun. 30, 2016
Jun. 30, 2015
Earnings Per Share, Basic, Two Class Method [Abstract]        
Net income and comprehensive income $ (10,066) $ 11,824 $ 3,033 $ 16,660
Income allocated to participating securities (28) (79) (55) (111)
Numerator for basic and diluted income per share - net income $ (10,094) $ 11,745 $ 2,978 $ 16,549
Denominator for basic income per share - weighted-average shares 30,252 30,783 30,356 30,726
Denominator for diluted income per share - adjusted weighted-average shares 30,252 31,104 30,557 31,088
Basic income per share (dollars per share) $ (0.33) $ 0.38 $ 0.10 $ 0.54
Diluted income per share (dollars per share) $ (0.33) $ 0.38 $ 0.10 $ 0.53
Total number anti-dilutive options, non-vested shares, and performance shares excluded from income per diluted share computation     324 118
Stock Option [Member]        
Earnings Per Share, Basic, Two Class Method [Abstract]        
Effect of dilutive stock options and non-vested shares   291 169 327
Total number anti-dilutive options, non-vested shares, and performance shares excluded from income per diluted share computation     301 97
Key Employee Performance Share Based Plan [Member]        
Earnings Per Share, Basic, Two Class Method [Abstract]        
Effect of dilutive stock options and non-vested shares   30 32 35
Total number anti-dilutive options, non-vested shares, and performance shares excluded from income per diluted share computation     23 21