Quarterly report pursuant to Section 13 or 15(d)

Stock-Based Compensation (Assump) (Details)

v3.7.0.1
Stock-Based Compensation (Assump) (Details) - $ / shares
3 Months Ended 6 Months Ended
Jun. 30, 2016
Jun. 30, 2017
Jun. 30, 2016
Summary of weighted average assumptions used to value options granted      
Grant date fair value of options (in dollars per share) $ 13.26 $ 14.51 $ 9.49
Volatility (as a percent) 42.40% 43.80% 42.20%
Risk-free interest rate (as a percent) 1.40% 2.10% 1.40%
Expected term (in years) 6 years 2 months 12 days 6 years 3 months 18 days 6 years 3 months 18 days