XML 39 R28.htm IDEA: XBRL DOCUMENT v3.20.2
Stock-Based Compensation - Stock-Based Compensation Expense (Details) - USD ($)
$ / shares in Units, $ in Thousands
1 Months Ended 3 Months Ended 9 Months Ended
May 31, 2017
Sep. 30, 2020
Sep. 30, 2019
Sep. 30, 2020
Sep. 30, 2019
Dec. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Options outstanding (in shares)   7,339,217   7,339,217   6,706,994
Weighted-average exercise price of stock options outstanding (in dollars per share)   $ 21.42   $ 21.42   $ 22.33
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]            
Stock-based compensation expense   $ 5,832 $ 5,398 $ 15,419 $ 14,081  
2016 Employee Stock Purchase Plan            
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Share-based compensation, number of shares authorized (in shares) 800,000          
Payroll deduction discount 10.00%          
Purchase price of common stock percent of the fair market value 85.00%          
Common stock purchased (in shares)       18,304    
Proceeds from stock plan       $ 300    
2003 Stock Incentive Plan            
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Options outstanding (in shares)   259,904   259,904    
Weighted-average exercise price of stock options outstanding (in dollars per share)   $ 2.73   $ 2.73    
Stock Incentive Plan 2013            
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Share-based compensation, number of shares authorized (in shares)   11,896,613   11,896,613    
Potential annual increase in shares reserved for future issuance (in shares)   1,960,168   1,960,168    
Potential annual increase in shares reserved for future issuance as percentage of outstanding share       4.00%    
Options outstanding (in shares)   7,079,313   7,079,313    
Weighted-average exercise price of stock options outstanding (in dollars per share)   $ 22.10   $ 22.10    
Research and Development            
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]            
Stock-based compensation expense   $ 3,059 2,765 $ 8,082 7,032  
General and Administrative            
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]            
Stock-based compensation expense   $ 2,773 $ 2,633 $ 7,337 $ 7,049