Stock-Based Compensation - Summary of Options Granted and Assumptions Utilized to Derive Fair Value (Details) (Stock Options [Member], USD $)
3 Months Ended
Mar. 31, 2015
Mar. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions and Methodology [Abstract]    
Total stock options granted 362,718 412,724
Volatility 36.30%  
Risk-free interest rate 1.60%  
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) $ 16.16 $ 15.51
Minimum [Member]
   
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions and Methodology [Abstract]    
Volatility   38.70%
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%
Risk-free interest rate   1.73%