Development Derivative Liability - Roll Forward (Details) - Derivative - USD ($) $ in Thousands |
3 Months Ended | |
|---|---|---|
Mar. 31, 2021 |
Mar. 31, 2020 |
|
| Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] | ||
| Funding during the period | $ 15,100 | |
| Change in fair value | 1,400 | $ 500 |
| SFJ Agreement | Collaborative Arrangement, Transaction with Party to Collaborative Arrangement | ||
| Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] | ||
| Balance at December 31, 2020 | 51,719 | |
| Funding during the period | 15,115 | |
| Change in fair value | 1,426 | |
| Balance at March 31, 2021 | $ 68,260 | |