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Stock-Based Compensation - Assumptions Used to Estimate The Fair Value of Time-Based Stock Options (Details) - Employee Stock Option
9 Months Ended
Sep. 30, 2017
Sep. 30, 2016
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions and Methodology [Abstract]    
Risk-free interest rate, minimum 1.88% 1.06%
Risk-free interest rate, maximum 2.02% 1.21%
Expected dividend yield (as a percent) 0.00% 0.00%
Expected term of option (in years) 5 years 4 years
Expected volatility (as a percent) 45.20%  
Expected volatility, minimum (as a percent)   46.70%
Expected volatility, maximum (as a percent)   47.00%
Weighted-average expected volatility (as a percent) 45.20% 46.70%