v3.5.0.2
Stock-Based Compensation - Stock Options (Details) - USD ($)
$ / shares in Units, shares in Thousands, $ in Thousands
 3 Months Ended 9 Months Ended 12 Months Ended
Sep. 30, 2016
Sep. 30, 2015
Sep. 30, 2016
Sep. 30, 2015
Dec. 31, 2015
Stock Options, additional disclosures          
Stock-based compensation expense $ 656 $ 116 $ 1,048 $ 251  
Stock Options          
Shares Under Option          
Outstanding at the beginning of the period (in shares)     5,177    
Granted (in shares)     721    
Exercised (in shares)     (626)    
Cancelled (in shares)     (65)    
Outstanding at the end of the period (in shares) 5,207   5,207   5,177
Weighted-Average Exercise Price          
Outstanding at the beginning of the period (in dollars per share)     $ 0.74    
Granted (in dollars per share)     16.86    
Exercised (in dollars per share)     0.69    
Cancelled (in dollars per share)     2.51    
Outstanding at the end of the period (in dollars per share) $ 2.96   $ 2.96   $ 0.74
Weighted-Average Contractual Life     7 years   7 years 4 months 24 days
Weighted average assumptions used to value options granted to employees          
Expected term (years) 6 years 1 month 6 days 5 years 10 months 24 days 6 years 6 years  
Volatility (as a percent) 59.00% 65.80% 58.90% 68.50%  
Risk-free interest rate (as a percent) 1.28% 1.68% 1.34% 1.57%  
Weighted average grant date fair value per share $ 9.83 $ 1.41 $ 9.27 $ 0.89  
Stock Options, additional disclosures          
Stock-based compensation expense $ 400 $ 100 $ 800 $ 300  
Unrecognized employee stock-based compensation $ 7,500   $ 7,500    
Unrecognized stock-based compensation, period for recognition     3 years 7 months 6 days