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Summary of Significant Accounting Policies - Preferred Stock Discount (Details) - Private Placement - Series X redeemable convertible preferred stock - USD ($) $ in Millions | 1 Months Ended | 9 Months Ended
--- | --- | ---
Feb. 28, 2021 | Sep. 30, 2023
Preferred stock discount |  |
Beneficial conversion feature | $ 19.6 |
Deferred stock issuance costs for Underwriting Agreement | $ 5.7 |
Non-cash dividend |  | $ 24.4
Value of remaining shares not yet converted |  | $ 0.9

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