v3.26.1
Stock-based compensation - Assumptions to determine grant-date fair value of stock options (Details) - Stock options
3 Months Ended
Jun. 30, 2026
Jun. 30, 2025
Stock-Based Compensation    
Risk-free interest rate 4.06% 3.97%
Expected term (in years) 6 years 6 years
Expected volatility 106.70% 76.30%
Expected dividend yield 0.00% 0.00%