Quarterly report pursuant to Section 13 or 15(d)

Stock-Based Compensation (Details 4)

v2.4.0.8
Stock-Based Compensation (Details 4) (Restricted Stock [Member], USD $)
3 Months Ended 6 Months Ended
Jun. 30, 2014
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Mar. 31, 2014
Jun. 30, 2014
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Restricted Stock [Member]
     
Stock-Based compensation      
Award vesting rights proportion (as a percent)     33.00%
Number of vesting rights anniversaries 3   3
Number of Shares      
Balance at the beginning of the period (in shares) 1,015,147 901,551 901,551
Granted (in shares)   240,626  
Vested (in shares) (5,671) (116,706)  
Forfeited (in shares) (4,312) (10,324)  
Balance at the end of the period (in shares) 1,005,164 1,015,147 1,005,164
Weighted-Average Grant Date Fair Value per Share      
Balance at the beginning of the period (in dollars per share) $ 22.69 $ 16.50 $ 16.50
Granted (in dollars per share)   $ 41.83  
Vested (in dollars per share) $ 24.60 $ 14.22  
Forfeited (in dollars per share) $ 29.79 $ 26.94  
Balance at the end of the period (in dollars per share) $ 22.65 $ 22.69 $ 22.65