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, USD $)
3 Months Ended 9 Months Ended
Sep. 30, 2014
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Jun. 30, 2014
Mar. 31, 2014
Sep. 30, 2014
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Restricted Stock
       
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) 1,005,164 1,015,147 901,551 901,551
Granted (in shares) 8,527   240,626  
Vested (in shares) (14,837) (5,671) (116,706)  
Forfeited (in shares) (5,336) (4,312) (10,324)  
Balance at the end of the period (in shares) 993,518 1,005,164 1,015,147 993,518
Weighted-Average Grant Date Fair Value per Share        
Balance at the beginning of the period (in dollars per share) $ 22.65 $ 22.69 $ 16.50 $ 16.50
Granted (in dollars per share) $ 46.62   $ 41.83  
Vested (in dollars per share) $ 26.97 $ 24.60 $ 14.22  
Forfeited (in dollars per share) $ 28.72 $ 29.79 $ 26.94  
Balance at the end of the period (in dollars per share) $ 22.76 $ 22.65 $ 22.69 $ 22.76