v3.26.3
Net Income (Loss) per Share - Schedule of Earnings Per Share, Basic and Diluted (Details) - USD ($)
$ / shares in Units, $ in Thousands
 3 Months Ended 9 Months Ended 12 Months Ended
Sep. 30, 2026
Jun. 30, 2026
Mar. 31, 2026
Sep. 30, 2025
Jun. 30, 2025
Mar. 31, 2025
Sep. 30, 2026
Sep. 30, 2025
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Earnings Per Share [Abstract]                      
Net income (loss) $ 55,442 $ (57,939) $ (94,391) $ (114,190) $ (42,281) $ (73,238) $ (96,888) $ (229,709)      
Weighted-average common, Series A preferred and Series B preferred shares outstanding, basic (in shares) 29,247,673     28,508,089     29,142,570 28,276,865      
Common stock issuable under equity plans (in shares) 1,050,361     0     0 0      
Common stock issuable under warrants (in shares) 15,103     0     0 0      
Weighted-average common, Series A preferred and Series B preferred shares outstanding, diluted (in shares) 30,313,137     28,508,089     29,142,570 28,276,865 28,409,706 26,908,070 21,562,581
Net income (loss) per common, Series A preferred, and Series B preferred share - basic (in dollars per share) $ 1.90     $ (4.01)     $ (3.32) $ (8.12) $ (10.15) $ (17.31) $ (17.33)
Net income (loss) per common, Series A preferred, and Series B preferred share - diluted (in dollars per share) $ 1.83     $ (4.01)     $ (3.32) $ (8.12) $ (10.15) $ (17.31) $ (17.33)