Stock Based Compensation - Stock Based Compensation Expense (Details) - USD ($) $ in Thousands |
3 Months Ended | 6 Months Ended | ||
---|---|---|---|---|
Jun. 30, 2020 |
Jun. 30, 2019 |
Jun. 30, 2020 |
Jun. 30, 2019 |
|
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items] | ||||
Stock based compensation expense | $ 980 | $ 994 | $ 2,060 | $ 1,934 |
Research and development | ||||
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items] | ||||
Stock based compensation expense | 173 | 378 | 473 | 801 |
General and administrative | ||||
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items] | ||||
Stock based compensation expense | $ 807 | $ 616 | $ 1,587 | $ 1,133 |