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Stock-Based Compensation - Narrative (Details) - USD ($) $ in Millions |  | 1 Months Ended | 6 Months Ended | 12 Months Ended |
--- | --- | --- | --- | --- | ---
May 15, 2018 | Feb. 28, 2025 | Jun. 30, 2026 | Dec. 31, 2025 | Dec. 31, 2024 | May 13, 2023
Stock-Based Compensation |  |  |  |  |  |
Inducement stock options granted to new employees (in shares) |  |  | 183,598 |  |  |
Inducement total authorized for grant (in shares) |  | 1,000,000 |  |  |  |
Common stock options |  |  |  |  |  |
Stock-Based Compensation |  |  |  |  |  |
Common stock shares reserved for issuance (in shares) |  |  | 15,503,480 |  |  |
Unrecognized compensation expense related to unvested stock options |  |  | $ 146.7 |  |  |
RSUs |  |  |  |  |  |
Stock-Based Compensation |  |  |  |  |  |
Common stock shares reserved for issuance (in shares) |  |  | 3,327,891 |  |  |
Unrecognized compensation expense related to unvested RSU awards |  |  | $ 248.9 |  |  |
PSUs |  |  |  |  |  |
Stock-Based Compensation |  |  |  |  |  |
Common stock shares reserved for issuance (in shares) |  |  | 267,435 |  |  |
Unrecognized compensation expense related to unvested RSU awards |  |  | $ 18.1 |  |  |
Unvested PSUs outstanding (in shares) |  |  | 92,219 |  |  |
Payout, percent |  |  | 100.00% |  |  |
2019 Incentive Plan |  |  |  |  |  |
Stock-Based Compensation |  |  |  |  |  |
Shares of common stock, maximum authorized for issuance (in shares) |  |  |  |  |  | 24,250,000
Number of additional shares authorized (in shares) |  |  |  | 10,000,000 | 3,000,000 |
Shares available for grant (in shares) |  |  | 10,334,057 |  |  |
2025 Inducement Plan |  |  |  |  |  |
Stock-Based Compensation |  |  |  |  |  |
Common stock shares reserved for issuance (in shares) |  |  | 516,635 |  |  |
Options outstanding (in shares) |  |  | 114,780 |  |  |
2018 ESPP |  |  |  |  |  |
Stock-Based Compensation |  |  |  |  |  |
Shares of common stock, maximum authorized for issuance (in shares) | 1,000,000 |  |  |  |  |
Number of additional shares authorized (in shares) | 1,200,000 |  |  |  |  |
Percentage of outstanding shares | 2.00% |  |  |  |  |

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