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Derivative financial instruments - Common stock warrants (Narrative) (Details) - USD ($) $ / shares in Units, $ in Thousands |  |  | 1 Months Ended | 12 Months Ended |
--- | --- | --- | --- | --- | ---
Jun. 22, 2023 | Oct. 24, 2022 | Jul. 31, 2023 | Jun. 30, 2023 | Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021 | Jun. 22, 2022
Derivative instruments |  |  |  |  |  |  |  |
Stock warrants issued (in shares) |  | 10,349,975 |  |  |  |  |  |
Gain (loss) on derivatives - common stock warrants |  |  |  |  | $ (5,742) | $ 362 | $ 0 |
Warrant Exchange Offer |  |  |  |  |  |  |  |
Derivative instruments |  |  |  |  |  |  |  |
Shares of common stock underlying each warrant (in shares) | 0.25 |  |  |  |  |  |  | 0.25
Common stock issued in warrant exchange (in shares) | 2,471,738 |  |  |  |  |  |  |
Number of warrants tendered (in shares) | 9,887,035 |  |  |  |  |  |  |
Amended Warrant Agreement Offer |  |  |  |  |  |  |  |
Derivative instruments |  |  |  |  |  |  |  |
Shares of common stock underlying each warrant (in shares) | 0.225 |  | 0.225 |  | 0.225 |  |  | 0.225
Fair value settlements |  |  | $ 700 | $ 17,000 |  |  |  |
Warrant Exchange Offer |  |  |  |  |  |  |  |
Derivative instruments |  |  |  |  |  |  |  |
Derivative liabilities - common stock warrants |  |  |  |  |  | 11,900 |  |
Gain (loss) on derivatives - common stock warrants |  |  |  |  | $ (5,700) | $ 400 |  |
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 usd per share) |  | $ 11.50 |  |  |  |  |  |
Period after business combination close in which warrants become exercisable |  | 30 days |  |  |  |  |  |
Common stock issued for exercise of warrants (in shares) |  |  |  |  | 461 |  |  |

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