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Weichai Transactions (Details) - USD ($) |  | 3 Months Ended | 9 Months Ended |
--- | --- | --- | --- | ---
Mar. 22, 2023 | Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2025 | Sep. 30, 2024 | Aug. 30, 2024
Subsidiary, Sale of Stock [Line Items] |  |  |  |  |  |
Term of collaborative arrangement (in years) | 3 years |  |  |  |  |
Related Party |  |  |  |  |  |
Subsidiary, Sale of Stock [Line Items] |  |  |  |  |  |
Purchased inventory |  | $ 3,100,000 | $ 13,200,000 | $ 35,400,000 | $ 19,900,000 |
Shareholder’s Loan Agreement | Subordinated Debt |  |  |  |  |  |
Subsidiary, Sale of Stock [Line Items] |  |  |  |  |  |
Debt instrument, face amount |  |  |  |  |  | $ 105,000,000.0

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