Quarterly report pursuant to Section 13 or 15(d)

Stock-based Compensation - Stock-based Compensation Expense (Details)

v3.10.0.1
Stock-based Compensation - Stock-based Compensation Expense (Details) - USD ($)
$ in Thousands
3 Months Ended 9 Months Ended
Sep. 30, 2018
Sep. 30, 2017
Sep. 30, 2018
Sep. 30, 2017
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]        
Total stock-based compensation expense $ 847 $ 2,038 $ 3,033 $ 4,893
Research and Development [Member]        
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]        
Total stock-based compensation expense 97 102 296 774
General and Administrative [Member]        
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]        
Total stock-based compensation expense $ 750 $ 1,936 $ 2,737 $ 4,119