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Fair Value Measurements - Convertible Promissory Note (Details) $ in Thousands | Sep. 30, 2025 USD ($) | Dec. 31, 2024 USD ($) | May 31, 2024 USD ($)
--- | --- | --- | ---
Fair Value Measurements |  |  |
Available-for-sale securities | $ 51,319 | $ 127,970 |
Convertible promissory notes | Fair value measured on recurring basis |  |  |
Fair Value Measurements |  |  |
Available-for-sale securities | 524 | 2,372 |
Convertible promissory notes | Fair value measured on recurring basis | Level 3 |  |  |
Fair Value Measurements |  |  |
Available-for-sale securities | $ 524 | $ 2,372 |
Rimere | Risk-free interest rate |  |  |
Fair Value Measurements |  |  |
Convertible Promissory Note, Measurement Input | 4.02 | 4.24 |
Rimere | Credit adjustment |  |  |
Fair Value Measurements |  |  |
Convertible Promissory Note, Measurement Input | 4.86 | 4.64 |
Rimere | Credit adjusted discount rate |  |  |
Fair Value Measurements |  |  |
Convertible Promissory Note, Measurement Input | 8.88 | 8.88 |
Bridge To Renewables, BTR | Fair value measured on recurring basis | Level 3 |  |  |
Fair Value Measurements |  |  |
Available-for-sale securities |  |  | $ 2,000
Bridge To Renewables, BTR | Risk-free interest rate |  |  |
Fair Value Measurements |  |  |
Convertible Promissory Note, Measurement Input |  | 4.31 |
Bridge To Renewables, BTR | Credit adjustment |  |  |
Fair Value Measurements |  |  |
Convertible Promissory Note, Measurement Input |  | 8.64 |
Bridge To Renewables, BTR | Credit adjusted discount rate |  |  |
Fair Value Measurements |  |  |
Convertible Promissory Note, Measurement Input |  | 12.95 |

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