Fair value measurements - Assets and Liabilities Measured on Recurring Basis (Details) - USD ($) $ in Thousands |
Jun. 30, 2026 |
Dec. 31, 2025 |
|---|---|---|
| Assets: | ||
| Debt Securities: | $ 191,676 | $ 138,677 |
| Total assets | 191,676 | 138,677 |
| Money market funds | ||
| Assets: | ||
| Debt Securities: | 98,399 | 14,410 |
| U.S. treasuries | ||
| Assets: | ||
| Debt Securities: | 93,277 | 124,267 |
| Level 1 | ||
| Assets: | ||
| Total assets | 98,399 | 21,283 |
| Level 1 | Money market funds | ||
| Assets: | ||
| Debt Securities: | 98,399 | 14,410 |
| Level 1 | U.S. treasuries | ||
| Assets: | ||
| Debt Securities: | 0 | 6,873 |
| Level 2 | ||
| Assets: | ||
| Total assets | 93,277 | 117,394 |
| Level 2 | Money market funds | ||
| Assets: | ||
| Debt Securities: | 0 | 0 |
| Level 2 | U.S. treasuries | ||
| Assets: | ||
| Debt Securities: | 93,277 | 117,394 |
| Level 3 | ||
| Assets: | ||
| Total assets | 0 | 0 |
| Level 3 | Money market funds | ||
| Assets: | ||
| Debt Securities: | 0 | 0 |
| Level 3 | U.S. treasuries | ||
| Assets: | ||
| Debt Securities: | $ 0 | $ 0 |