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Organization and Operations - Stock Purchase Agreement and Series X Preferred Stock (Details) |  | 1 Months Ended | 9 Months Ended |  |  |
--- | --- | --- | --- | --- | --- | ---
Sep. 30, 2021 shares | Feb. 28, 2021 USD ($) | Sep. 30, 2021 USD ($) shares | Jun. 02, 2021 | Jan. 28, 2021 | Dec. 31, 2020 shares
Stock Purchase Agreement and Series X Preferred Stock |  |  |  |  |  |
Net proceeds from issuance of private placement |  |  | $ 104,261,000 |  |  |
Issuance of common stock upon the conversion of preferred stock (in shares) | shares | 9,103,664 |  |  |  |  |
Minimum |  |  |  |  |  |
Stock Purchase Agreement and Series X Preferred Stock |  |  |  |  |  |
Common stock, percentage of beneficial ownership initially, after conversion | 4.99% |  | 4.99% |  |  |
Common stock, percentage of beneficial ownership thereafter, after conversion | 4.99% |  | 4.99% |  |  |
Maximum |  |  |  |  |  |
Stock Purchase Agreement and Series X Preferred Stock |  |  |  |  |  |
Common stock, percentage of beneficial ownership initially, after conversion | 9.99% |  | 9.99% |  |  |
Common stock, percentage of beneficial ownership thereafter, after conversion | 19.99% |  | 19.99% |  |  |
Quellis Biosciences, Inc | Stock Purchase Agreement |  |  |  |  |  |
Stock Purchase Agreement and Series X Preferred Stock |  |  |  |  |  |
Beneficial conversion feature |  |  | $ 19,600,000 |  |  |
Series X redeemable convertible preferred stock |  |  |  |  |  |
Stock Purchase Agreement and Series X Preferred Stock |  |  |  |  |  |
Issuance of preferred stock in a private offering of public equity, net of issuance costs (in shares) | shares |  |  | 35,573 |  |  |
Shares issued |  | $ 88,882 |  |  |  |
Number of shares of common stock into which each share of Series X Preferred Stock may be converted | 166.67 |  | 166.67 | 166.67 |  |
Conversion of preferred stock into common stock (in shares) | shares | 54,622 |  |  |  |  |
Number of common shares issuable upon conversion of preferred stock (in shares) | shares | 5,242,501 |  | 5,242,501 |  |  |
Preferred stock, outstanding (in shares) | shares | 31,455 |  | 31,455 |  |  | 0
Series X redeemable convertible preferred stock | Outstanding shares issued in merger |  |  |  |  |  |
Stock Purchase Agreement and Series X Preferred Stock |  |  |  |  |  |
Shares issued |  | 50,504 |  |  |  |
Series X redeemable convertible preferred stock | Outstanding shares issued in February 2021 Financing |  |  |  |  |  |
Stock Purchase Agreement and Series X Preferred Stock |  |  |  |  |  |
Shares issued |  | 35,573 |  |  |  |
Series X redeemable convertible preferred stock | Warrants assumed in merger |  |  |  |  |  |
Stock Purchase Agreement and Series X Preferred Stock |  |  |  |  |  |
Shares issued |  | $ 2,805 |  |  |  |
Series X redeemable convertible preferred stock | Quellis Biosciences, Inc |  |  |  |  |  |
Stock Purchase Agreement and Series X Preferred Stock |  |  |  |  |  |
Number of shares of common stock into which each share of Series X Preferred Stock may be converted | 166.67 |  | 166.67 |  | 166.67 |
Series X redeemable convertible preferred stock | Quellis Biosciences, Inc | Stock Purchase Agreement |  |  |  |  |  |
Stock Purchase Agreement and Series X Preferred Stock |  |  |  |  |  |
Issuance of preferred stock in a private offering of public equity, net of issuance costs (in shares) | shares |  |  | 35,573 |  |  |
Gross proceeds from issuance of preferred stock in a private offering |  |  | $ 110,000,000.0 |  |  |
Net proceeds from issuance of private placement |  |  | 104,300,000 |  |  |
Issuance costs |  |  | $ 5,700,000 |  |  |

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