XML 54 R44.htm IDEA: XBRL DOCUMENT v3.10.0.1
Stock-Based Compensation - Schedule of Assumptions to Estimate Fair Value of Stock Options for Employees and Non-Employees Using Black-Scholes Option Pricing Model (Details) - Options Issued and Outstanding - $ / shares
3 Months Ended 6 Months Ended
Jun. 30, 2018
Jun. 30, 2018
Employees    
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]    
Expected term (in years) 6 years 7 months 6 days  
Expected volatility, minimum 77.40% 76.10%
Expected volatility, maximum 77.70% 77.70%
Risk-free interest rate, minimum 2.60% 2.40%
Risk-free interest rate, maximum 2.80% 2.80%
Expected dividend yield 0.00% 0.00%
Non-employees    
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]    
Fair value of common stock   $ 15.45
Expected term (in years)   10 years
Expected dividend yield   0.00%
Expected volatility   77.90%
Risk-free interest rate   2.70%
Minimum | Employees    
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]    
Fair value of common stock $ 8.57 $ 8.57
Expected term (in years)   5 years 9 months 18 days
Maximum | Employees    
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]    
Fair value of common stock $ 9.91 $ 15.45
Expected term (in years)   6 years 7 months 6 days