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Derivative Financial Instruments - Common stock warrants (Narrative) (Details) $ / shares in Units, $ in Thousands |  |  | 1 Months Ended | 3 Months Ended | 9 Months Ended
--- | --- | --- | --- | --- | ---
Jun. 22, 2023 shares | Oct. 24, 2022 $ / shares shares | Jul. 31, 2023 USD ($) shares | Jun. 30, 2023 USD ($) | Sep. 30, 2024 USD ($) | Sep. 30, 2023 USD ($) shares | Sep. 30, 2024 USD ($) | Sep. 30, 2023 USD ($) shares
Derivative instruments |  |  |  |  |  |  |  |
Stock warrants issued (in shares) |  | 10,349,975 |  |  |  |  |  |
Loss from change in fair value of warrants | $ |  |  |  |  | $ 0 | $ 8 | $ 0 | $ 5,742
Warrant |  |  |  |  |  |  |  |
Derivative instruments |  |  |  |  |  |  |  |
Stock warrants issued (in shares) |  | 10,349,975 |  |  |  |  |  |
Shares of common stock underlying each warrant (in shares) |  | 1 |  |  |  |  |  |
Exercise price of warrants (in dollars per share) | $ / shares |  | $ 11.50 |  |  |  |  |  |
Period after business combination close in which warrants become exercisable |  | 30 days |  |  |  |  |  |
Class of warrant or right, warrants exercised (in shares) |  | 461 |  |  |  |  |  |
Warrant Exchange Offer |  |  |  |  |  |  |  |
Derivative instruments |  |  |  |  |  |  |  |
Loss from change in fair value of warrants | $ |  |  |  |  |  |  |  | $ 5,700
Common stock issued in warrant exchange (in shares) | 2,471,738 |  |  |  |  |  |  |
Number of warrants tendered (shares) | 9,887,035 |  |  |  |  |  |  |
Shares of common stock underlying each warrant (in shares) | 0.25 |  |  |  |  |  |  |
Amended Warrant Agreement Offer |  |  |  |  |  |  |  |
Derivative instruments |  |  |  |  |  |  |  |
Shares of common stock underlying each warrant (in shares) | 0.225 |  | 0.225 |  |  |  |  |
Warrants outstanding (in shares) |  |  | 0 |  |  | 0 |  | 0
Fair value settlements | $ |  |  | $ 700 | $ 17,000 |  |  |  |

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