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Fair Value Measurements - Narrative (Details) - USD ($) $ in Thousands |  |  | 3 Months Ended | 9 Months Ended
--- | --- | --- | --- | ---
Aug. 01, 2025 | Jul. 30, 2025 | Sep. 30, 2025 | Sep. 30, 2025 | Sep. 30, 2024
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |
Loss on issuance of convertible notes |  |  | $ 9,952 | $ 9,952 |
Debt conversion, number of shares issued | 2,810,428 | 15,176,862 |  |  |
Preferred stock warrant liability |  |  |  |  |
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |
Change in fair value, gain (loss) included in earnings |  |  |  | (256) | $ (75)
Fair value, issuances |  |  |  | 0 |
Series E purchase option |  |  |  |  |
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |
Change in fair value, gain (loss) included in earnings |  |  |  | (11,719) |
Fair value, issuances |  |  |  | 218 |
Convertible notes |  |  |  |  |
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |
Change in fair value, gain (loss) included in earnings |  |  |  | $ 7,739 |
Fair value assumption, IPO scenario |  |  | 97.00% | 97.00% |
Fair value assumption, liquidation event |  |  | 3.00% | 3.00% |
Fair value, issuances |  |  |  | $ 49,815 |

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- Definition The number of shares issued in exchange for the original debt being converted in a noncash (or part noncash) transaction. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or payments in the period. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 3 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482913/230-10-50-3 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 5 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482913/230-10-50-5 + Details
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