Common stock - Warrants (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023	Dec. 31, 2023
Common stock
Warrants outstanding	0		0		500,000
Exercise price					$ 10.00
Exercise of common stock warrants	0	0	373,057	0
Proceeds from warrant exercises			$ 3,731
Number of warrants expired	126,943		126,943