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Stockholders' Equity - Summary of Assumptions Used to Value Stock Option Grants Using Lattice-Binomial Model (Details)
$ / shares in Units, $ in Thousands
3 Months Ended
Mar. 31, 2017
USD ($)
$ / shares
Mar. 31, 2016
USD ($)
$ / shares
Stockholders' Equity and Stock-based Compensation Disclosure [Abstract]    
Share-based payment award, expiration period (in years) 10 years  
Dividend yield 0.00% 0.00%
Expected volatility 37.00% 50.00%
Risk-free interest rate 2.45% 2.04%
Suboptimal exercise factor 2.48 2.48
Weighted-average fair value (in dollars per share) | $ / shares $ 62.36 $ 50.76
Stock-based compensation expense $ 44,888 $ 42,422
Total income tax impact on provision (in thousands) $ 14,701 $ 15,963