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Stockholders Deficit and Redeemable Convertible Preferred Stock (Additional Information) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands |  |  |  | 9 Months Ended |  |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | ---
Aug. 28, 2025 | Nov. 15, 2024 | Oct. 31, 2024 | Sep. 30, 2025 | Sep. 30, 2024 | Aug. 08, 2025 | Jul. 16, 2025 | Mar. 31, 2025 | Dec. 31, 2024
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |
Proceeds from Issuance of Common Stock |  |  |  | $ 943,736 | $ 0 |  |  |  |
Sale of Stock, Consideration Received on Transaction |  |  |  | $ 244,700 |  |  |  |  |
Accured Interest From Subordinated Convertible Promissory Notes |  |  | $ 25,800 |  |  |  |  |  |
Common stock, shares, issued (in shares) |  |  |  | 148,138 |  |  |  |  | 13,241
Purchase of an Aggregate of Common Warrant |  |  |  | $ 1,000 |  |  |  |  |
Warrant Exercise Price Per Share |  |  |  | $ 0.91 |  |  |  |  |
Common stock, $0.0001 par value, 1,000,000 and 154,397 shares authorized as of September 30, 2025 and December 31, 2024, respectively; 148,138 and 13,241 shares issued and outstanding as of September 30, 2025 and December 31, 2024, respectively |  |  |  | $ 16 |  |  |  |  | $ 1
Number of the Shares Underlying the RPM Call Option |  | 1,900 |  |  |  |  |  |  |
IPO Closing Preferred Stock Dividend |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |
Dividends, Preferred Stock, Cash | $ 5,000 |  |  |  |  |  |  |  |
Convertible Preferred Stock |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |
Common stock, shares, issued (in shares) |  |  |  |  |  | 105,800 |  |  |
Series D Preferred Stock |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |
Proceeds from Issuance of Common Stock |  |  | $ 175,500 |  |  |  |  |  |
Preferred Stock, Par or Stated Value Per Share |  |  |  | $ 16.9213 |  |  |  |  |
Preferred Stock, Value, Issued |  |  |  | $ 250,000 |  |  |  | $ 250,000 |
Series D-1 Preferred Stock |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |
Number Of Share Sold |  | 100 | 10,400 |  |  |  |  |  |
Proceeds from Issuance of Common Stock |  | $ 1,300 |  |  |  |  |  |  |
Sale of Stock, Consideration Received on Transaction |  |  |  | 5,000 |  |  |  |  |
Shares Issued, Price Per Share |  | $ 16.9213 | $ 16.9213 |  |  |  |  |  |
Common stock, $0.0001 par value, 1,000,000 and 154,397 shares authorized as of September 30, 2025 and December 31, 2024, respectively; 148,138 and 13,241 shares issued and outstanding as of September 30, 2025 and December 31, 2024, respectively |  |  |  | $ 1,300 |  |  |  |  |
Preferred stock, shares issued (in shares) |  |  |  | 1,800 |  |  |  |  |
Series D-3 Preferred Stock |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |
Common stock, shares, issued (in shares) |  |  |  |  |  |  | 3,300 |  |
Majority Sponsor Top-Up |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |
Preferred Stock, Value, Issued |  |  |  | $ 125,000 |  |  |  |  |

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