Stockholders' equity - Warrants transactions (Details) - USD ($) $ / shares in Units, $ in Thousands |
6 Months Ended | 12 Months Ended |
|---|---|---|
Jun. 30, 2025 |
Dec. 31, 2024 |
|
| Common stock warrants | ||
| Number of shares | ||
| Outstanding (in shares) | 1,895 | 1,895 |
| Weighted average exercise price (per share) | ||
| Outstanding (in dollars per share) | $ 53.45 | $ 53.45 |
| Weighted average remaining contractual life (in years) | ||
| Outstanding (in years) | 1 year 2 months 12 days | 1 year 8 months 12 days |
| Penny Warrants | ||
| Number of shares | ||
| Issued (in shares) | 2,000,000 | |
| Outstanding (in shares) | 2,000,000 | |
| Aggregate intrinsic value | ||
| Outstanding (in dollars) | $ 1,935 | |
| Weighted average remaining contractual life (in years) | ||
| Outstanding (in years) | 2 years 7 months 6 days |