Quarterly report pursuant to Section 13 or 15(d)

Employee Stock Purchase Plan and Stock-Based Compensation - Schedule of Stock-Based Compensation Expense Recognized (Details)

v3.10.0.1
Employee Stock Purchase Plan and Stock-Based Compensation - Schedule of Stock-Based Compensation Expense Recognized (Details) - USD ($)
 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 $ 321 $ 593 $ 802 $ 1,126
Research and Development        
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]        
Total stock-based compensation expense 65 19 160 91
General and Administrative        
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]        
Total stock-based compensation expense $ 256 $ 574 $ 642 $ 1,035