Stock-Based Compensation (Details) 2 (USD $)
 6 Months Ended
Jun. 30, 2014
Jun. 30, 2013
Stock Options [Member]
    
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions and Methodology [Abstract]    
Total stock options granted 427,463 365,080
Volatility   45.40%
Risk-free interest rate   0.81%
Expected life (in years) 4 years 6 months 4 years 6 months
Dividend yield 0.00% 0.00%
Weighted-average grant date fair value (in dollars per share) $ 15.48 $ 21.44
Minimum [Member]
    
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions and Methodology [Abstract]    
Volatility 38.40%  
Minimum [Member] | Stock Options [Member]
    
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions and Methodology [Abstract]    
Risk-free interest rate 1.54%  
Maximum [Member]
    
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions and Methodology [Abstract]    
Volatility 39.20%  
Maximum [Member] | Stock Options [Member]
    
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions and Methodology [Abstract]    
Risk-free interest rate 1.73%