Nature of business and basis of presentation (Details) - USD ($) $ in Thousands	3 Months Ended				6 Months Ended
	Jun. 30, 2023	Mar. 31, 2023	Jun. 30, 2022	Mar. 31, 2022	Jun. 30, 2023	Jun. 30, 2022	Dec. 31, 2022
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Net loss	$ (54,307)	$ (56,163)	$ (52,219)	$ (47,258)	$ (110,470)	$ (99,477)
Accumulated deficit	$ (765,161)				$ (765,161)		$ (654,691)