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v3.20.4

Related Party Transactions - Additional Information (Details) - USD ($) |  | 12 Months Ended
--- | --- | ---
Jan. 30, 2020 | Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Follow-on-offering |  |  |  |
Related Party Transaction [Line Items] |  |  |  |
Public offerings | 9,602,500 |  |  |
Share price | $ 25.00 |  |  |
Follow-on-offering | Director |  |  |  |
Related Party Transaction [Line Items] |  |  |  |
Public offerings | 20,000 |  |  |
Share price | $ 25.00 |  |  |
Adimab |  |  |  |
Related Party Transaction [Line Items] |  |  |  |
Related party transaction expenses |  | $ 0 | $ 2,800,000 | $ 2,300,000
Accrued liabilities due to related parties |  | 0 | $ 0 |
Two Thousand Fourteen Adimab Agreement | Maximum |  |  |  |
Related Party Transaction [Line Items] |  |  |  |
Future milestone payments owed |  | $ 3,500,000 |  |

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