v3.25.4
Warrants, Redeemable Convertible Preferred Stock and Stockholders' Equity - Schedule of Redeemable Convertible Preferred Stock (Details) - USD ($)
$ in Thousands
 3 Months Ended 9 Months Ended 12 Months Ended
Sep. 30, 2025
Sep. 30, 2024
Sep. 30, 2025
Sep. 30, 2024
Dec. 31, 2024
Dec. 31, 2023
Temporary Equity [Line Items]            
Beginning balance     $ 378,150 $ 320,161 $ 320,161  
Ending balance $ 0   0   378,150 $ 320,161
Series Seed Redeemable Convertible Preferred Stock [Member]            
Temporary Equity [Line Items]            
Beginning balance $ 2,473 $ 2,473 $ 2,473 $ 2,473 $ 2,473 $ 2,473
Beginning balance (in shares) 5,045,368 5,045,368 5,045,368 5,045,368 5,045,368 5,045,368
Issuance of Series G preferred stock, net   $ 0   $ 0   $ 0
Issuance of Series G preferred stock, net (in shares)   0   0   0
Conversion of preferred stock to common stock upon IPO $ (2,473)   $ (2,473)      
Conversion of preferred stock to common stock upon IPO (in shares) (5,045,368)   (5,045,368)      
Ending balance $ 0 $ 2,473 $ 0 $ 2,473 $ 2,473 $ 2,473
Ending balance (in shares) 0 5,045,368 0 5,045,368 5,045,368 5,045,368
Series A Redeemable Convertible Preferred Stock [Member]            
Temporary Equity [Line Items]            
Beginning balance $ 5,179 $ 5,179 $ 5,179 $ 5,179 $ 5,179 $ 5,179
Beginning balance (in shares) 8,255,614 8,255,614 8,255,614 8,255,614 8,255,614 8,255,614
Issuance of Series G preferred stock, net   $ 0   $ 0   $ 0
Issuance of Series G preferred stock, net (in shares)   0   0   0
Conversion of preferred stock to common stock upon IPO $ (5,179)   $ (5,179)      
Conversion of preferred stock to common stock upon IPO (in shares) (8,255,614)   (8,255,614)      
Ending balance $ 0 $ 5,179 $ 0 $ 5,179 $ 5,179 $ 5,179
Ending balance (in shares) 0 8,255,614 0 8,255,614 8,255,614 8,255,614
Series B Redeemable Convertible Preferred Stock [Member]            
Temporary Equity [Line Items]            
Beginning balance $ 10,827 $ 10,827 $ 10,827 $ 10,827 $ 10,827 $ 10,228
Beginning balance (in shares) 18,894,315 18,894,315 18,894,315 18,894,315 18,894,315 18,456,996
Issuance of Series G preferred stock, net   $ 0   $ 0   $ 0
Issuance of Series G preferred stock, net (in shares)   0   0   0
Exercise of warrants (in shares)           437,319
Exercise of warrants           $ 599
Conversion of preferred stock to common stock upon IPO $ (10,827)   $ (10,827)      
Conversion of preferred stock to common stock upon IPO (in shares) (18,894,315)   (18,894,315)      
Ending balance $ 0 $ 10,827 $ 0 $ 10,827 $ 10,827 $ 10,827
Ending balance (in shares) 0 18,894,315 0 18,894,315 18,894,315 18,894,315
Series C Redeemable Convertible Preferred Stock [Member]            
Temporary Equity [Line Items]            
Beginning balance $ 24,908 $ 24,908 $ 24,908 $ 24,908 $ 24,908 $ 24,908
Beginning balance (in shares) 42,890,840 42,890,840 42,890,840 42,890,840 42,890,840 42,890,840
Issuance of Series G preferred stock, net   $ 0   $ 0   $ 0
Issuance of Series G preferred stock, net (in shares)   0   0   0
Conversion of preferred stock to common stock upon IPO $ (24,908)   $ (24,908)      
Conversion of preferred stock to common stock upon IPO (in shares) (42,890,840)   (42,890,840)      
Ending balance $ 0 $ 24,908 $ 0 $ 24,908 $ 24,908 $ 24,908
Ending balance (in shares) 0 42,890,840 0 42,890,840 42,890,840 42,890,840
Series D Redeemable Convertible Preferred Stock [Member]            
Temporary Equity [Line Items]            
Beginning balance $ 33,411 $ 33,411 $ 33,411 $ 33,411 $ 33,411 $ 33,411
Beginning balance (in shares) 39,656,811 39,656,811 39,656,811 39,656,811 39,656,811 39,656,811
Issuance of Series G preferred stock, net   $ 0   $ 0   $ 0
Issuance of Series G preferred stock, net (in shares)   0   0   0
Conversion of preferred stock to common stock upon IPO $ (33,411)   $ (33,411)      
Conversion of preferred stock to common stock upon IPO (in shares) (39,656,811)   (39,656,811)      
Ending balance $ 0 $ 33,411 $ 0 $ 33,411 $ 33,411 $ 33,411
Ending balance (in shares) 0 39,656,811 0 39,656,811 39,656,811 39,656,811
Series E Redeemable Convertible Preferred Stock [Member]            
Temporary Equity [Line Items]            
Beginning balance $ 29,738 $ 29,738 $ 29,738 $ 29,738 $ 29,738 $ 29,738
Beginning balance (in shares) 29,019,153 29,019,153 29,019,153 29,019,153 29,019,153 29,019,153
Issuance of Series G preferred stock, net   $ 0   $ 0   $ 0
Issuance of Series G preferred stock, net (in shares)   0   0   0
Conversion of preferred stock to common stock upon IPO $ (29,738)   $ (29,738)      
Conversion of preferred stock to common stock upon IPO (in shares) (29,019,153)   (29,019,153)      
Ending balance $ 0 $ 29,738 $ 0 $ 29,738 $ 29,738 $ 29,738
Ending balance (in shares) 0 29,019,153 0 29,019,153 29,019,153 29,019,153
Series F Redeemable Convertible Preferred Stock [Member]            
Temporary Equity [Line Items]            
Beginning balance $ 132,975 $ 132,975 $ 132,975 $ 132,975 $ 132,975 $ 132,975
Beginning balance (in shares) 74,840,147 74,840,147 74,840,147 74,840,147 74,840,147 74,840,147
Issuance of Series G preferred stock, net   $ 0   $ 0   $ 0
Issuance of Series G preferred stock, net (in shares)   0   0   0
Conversion of preferred stock to common stock upon IPO $ (132,975)   $ (132,975)      
Conversion of preferred stock to common stock upon IPO (in shares) (74,840,147)   (74,840,147)      
Ending balance $ 0 $ 132,975 $ 0 $ 132,975 $ 132,975 $ 132,975
Ending balance (in shares) 0 74,840,147 0 74,840,147 74,840,147 74,840,147
Series F-1 Redeemable Convertible Preferred Stock [Member]            
Temporary Equity [Line Items]            
Beginning balance $ 49,392 $ 49,392 $ 49,392 $ 49,392 $ 49,392 $ 49,392
Beginning balance (in shares) 23,664,027 23,664,027 23,664,027 23,664,027 23,664,027 23,664,027
Issuance of Series G preferred stock, net   $ 0   $ 0   $ 0
Issuance of Series G preferred stock, net (in shares)   0   0   0
Conversion of preferred stock to common stock upon IPO $ (49,392)   $ (49,392)      
Conversion of preferred stock to common stock upon IPO (in shares) (23,664,027)   (23,664,027)      
Ending balance $ 0 $ 49,392 $ 0 $ 49,392 $ 49,392 $ 49,392
Ending balance (in shares) 0 23,664,027 0 23,664,027 23,664,027 23,664,027
Series G Redeemable Convertible Preferred Stock [Member]            
Temporary Equity [Line Items]            
Beginning balance $ 89,247 $ 82,754 $ 89,247 $ 31,258 $ 31,258 $ 0
Beginning balance (in shares) 99,229,883 92,041,042 99,229,883 34,972,704 34,972,704 0
Issuance of Series G preferred stock, net   $ 6,487   $ 57,983 $ 57,989 $ 31,258
Issuance of Series G preferred stock, net (in shares)   7,188,841   64,257,179 64,257,179 34,972,704
Conversion of preferred stock to common stock upon IPO $ (89,247)   $ (89,247)      
Conversion of preferred stock to common stock upon IPO (in shares) (99,229,883)   (99,229,883)      
Ending balance $ 0 $ 89,241 $ 0 $ 89,241 $ 89,247 $ 31,258
Ending balance (in shares) 0 99,229,883 0 99,229,883 99,229,883 34,972,704