v3.25.1
Share-Based Compensation - Non-vested share options (Details) - $ / shares
 3 Months Ended
Mar. 31, 2025
Mar. 31, 2024
Plans 2011 and 2019 and 2021 Inducement    
Number of options    
Non-vested share options at end of year 3,350,568 2,509,188
Weighted average fair value    
Non-vested at end of year $ 2.18 $ 3.71
2019 Plan    
Number of options    
Non-vested at beginning of year 2,754,054 3,178,475
Granted 1,151,400 45,000
Vested, outstanding (944,594) (604,713)
Forfeited   (386,053)
Non-vested share options at end of year 2,960,860 2,232,709
Weighted average fair value    
Non-vested at beginning of year $ 2.33 $ 3.64
Granted 1.64 1.12
Vested, outstanding 2.12 3.54
Forfeited   3.47
Non-vested at end of year $ 2.13 $ 3.64
2021 Inducement Plan    
Number of options    
Non-vested at beginning of year 176,709 403,167
Granted 244,000  
Vested, outstanding (31,001) (28,438)
Forfeited   (98,250)
Non-vested share options at end of year 389,708 276,479
Weighted average fair value    
Non-vested at beginning of year $ 4.19 $ 4.07
Granted 1.6  
Vested, outstanding 4.53 4.85
Forfeited   $ 3.31
Non-vested at end of year $ 2.54