Income taxes - Summary of income tax (benefit) expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Current tax provision:
Current federal provision	$ 0	$ 0
Current state provision	76	0
Current foreign provision	1,204	0
Total current provision	1,280	0
Deferred tax provision:
Deferred federal provision	0	0
Deferred state provision	0	0
Deferred foreign provision	0	0
Total tax provision	$ 1,280	$ 0