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Organization and Operations - Reverse Stock Split, Agreement and Plan of Merger (Details) - USD ($) $ / shares in Units, $ in Millions |  | 9 Months Ended |  |
--- | --- | --- | --- | ---
Jan. 28, 2021 | Sep. 30, 2021 | Jun. 02, 2021 | Dec. 31, 2020
Agreement and Plan of Merger |  |  |  |
Reverse stock split ratio |  | 0.1667 |  |
Common stock, par value (in dollars per share) |  | $ 0.001 |  | $ 0.001
Series X redeemable convertible preferred stock |  |  |  |
Agreement and Plan of Merger |  |  |  |
Issuance of preferred stock upon acquisition of Quellis (in shares) |  | 50,504 |  |
Common stock |  |  |  |
Agreement and Plan of Merger |  |  |  |
Shares issued on acquisition (in shares) |  | 555,444 |  |
Warrants to purchase number of shares |  |  | 467,500 |
Common stock | Series X redeemable convertible preferred stock |  |  |  |
Agreement and Plan of Merger |  |  |  |
Exercise Price (in dollars per share) |  |  | $ 2.10 |
Quellis Biosciences, Inc | Series X redeemable convertible preferred stock |  |  |  |
Agreement and Plan of Merger |  |  |  |
Issuance of preferred stock upon acquisition of Quellis (in shares) | 50,504 |  |  |
Conversion value on closing date | $ 122.7 |  |  |
Warrants to purchase number of shares | 2,805 |  |  |
Exercise Price (in dollars per share) | $ 341.70 |  |  |
Quellis Biosciences, Inc | Common stock |  |  |  |
Agreement and Plan of Merger |  |  |  |
Shares issued on acquisition (in shares) | 555,444 |  |  |
Common stock, par value (in dollars per share) | $ 0.001 |  |  |
Number of options assumed in Quellis Acquisition | 55,414 |  |  |
Warrants to purchase number of shares | 30,856 |  |  |
Exercise Price (in dollars per share) | $ 2.10 |  | $ 2.10 |

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