Quarterly report pursuant to Section 13 or 15(d)

Net Income Per Share (Details)

v2.4.0.8
Net Income Per Share (Details) (USD $)
In Thousands, except Per Share data, unless otherwise specified
 3 Months Ended
Mar. 31, 2014
Mar. 31, 2013
Numerator [Abstract]    
Numerator for basic and diluted income per share - net income $ 10,202 $ 10,855
Denominator [Abstract]    
Denominator for basic income per share - weighted-average shares 30,732 29,511
Denominator for diluted income per share - adjusted weighted-average shares 31,314 30,264
Basic income per share (dollars per share) $ 0.33 $ 0.37
Diluted income per share (dollars per share) $ 0.33 $ 0.36
Total number anti-dilutive options, non-vested shares, and performance shares excluded from income per diluted share computation 174 166
Stock Option [Member]
    
Denominator [Abstract]    
Effect of dilutive stock options and non-vested shares 466 606
Total number anti-dilutive options, non-vested shares, and performance shares excluded from income per diluted share computation 160 150
Key Employee Performance Share Based Plan [Member]
    
Denominator [Abstract]    
Effect of dilutive stock options and non-vested shares 58 53
Total number anti-dilutive options, non-vested shares, and performance shares excluded from income per diluted share computation 14 16
Nonvested Shares [Member]
    
Denominator [Abstract]    
Effect of dilutive stock options and non-vested shares 58 94