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Summary of Significant Accounting Policies - Preferred Stock Discount (Details) - USD ($) $ in Thousands | 1 Months Ended | 3 Months Ended
--- | --- | ---
Feb. 28, 2021 | Mar. 31, 2022 | Mar. 31, 2021
Preferred stock discount |  |  |
Beneficial conversion feature |  |  | $ 19,565
Private Placement | Series X redeemable convertible preferred stock |  |  |
Preferred stock discount |  |  |
Beneficial conversion feature | $ 19,600 |  |
Issuance costs | $ 5,700 |  |
Non-cash dividend |  | $ 24,400 |
Value of remaining shares not yet converted |  | $ 900 |

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