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Asset Acquisition - Additional Information (Details) - USD ($) shares in Thousands | 1 Months Ended | 3 Months Ended | 9 Months Ended
--- | --- | --- | ---
May 31, 2020 | Sep. 30, 2021 | Sep. 30, 2020 | Sep. 30, 2021 | Sep. 30, 2020
Business Acquisition [Line Items] |  |  |  |  |
Stock issued during period value acquisitions |  |  |  |  | $ 4,000,000
Immulus, Inc [Member] |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |
Percentage of outstanding equity acquired | 100.00% |  |  |  |
Payments to acquire businesses, gross | $ 3,500,000 |  |  |  |
Business acquisition, transaction costs | 500,000 |  |  |  |
Stock issued during period value acquisitions | $ 4,000,000.0 |  |  |  |
Stock issued during period, shares, acquisitions | 688,463 |  |  |  |
Total consideration | $ 8,000,000.0 |  |  |  |
Milestone payments expense incurred |  | $ 0 | $ 0 | $ 0 | $ 0
Immulus, Inc [Member] | Maximum [Member] |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |
Milestone payments payable | $ 37,000,000.0 |  |  |  |

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