XML 54 R44.htm IDEA: XBRL DOCUMENT v3.23.1
Share-based compensation - Assumptions (Details) - $ / shares
3 Months Ended
Mar. 31, 2023
Mar. 31, 2022
Share-based compensation    
Expected volatility 87.90% 83.50%
Risk-free interest rate 3.90% 1.70%
Expected term (in years) 5 years 11 months 15 days 6 years 29 days
Expected dividend yield 0.00%  
Fair value of common stock $ 5.39 $ 10.58