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Collaboration and Other Agreements - NIAID Contract (Details) |  | 3 Months Ended | 12 Months Ended
--- | --- | --- | ---
Sep. 15, 2015 USD ($) Molecule | Mar. 31, 2020 USD ($) | Mar. 31, 2019 USD ($) | Dec. 31, 2017 USD ($)
Collaboration And Other Agreements [Line Items] |  |  |  |
Revenues |  | $ 13,682,000 | $ 9,662,000 |
NIAID |  |  |  |
Collaboration And Other Agreements [Line Items] |  |  |  |
Commercialization of molecules | Molecule | 2 |  |  |
Base period | $ 7,500,000 |  |  |
Additional development funding options under agreement | 17,000,000.0 |  |  |
Total potential value | $ 24,500,000 |  |  |
Proceeds from additional development funding options under agreement |  |  |  | $ 10,800,000
Revenues From Grants | NIAID |  |  |  |
Collaboration And Other Agreements [Line Items] |  |  |  |
Revenues |  | $ 700,000 | $ 200,000 |

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