Loss per share - Schedule of basic and diluted loss per share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended				6 Months Ended
	Jun. 30, 2022	Mar. 31, 2022	Jun. 30, 2021	Mar. 31, 2021	Jun. 30, 2022	Jun. 30, 2021
Numerator:
Net loss	$ (27,412)	$ (31,620)	$ (22,580)	$ (20,971)	$ (59,032)	$ (43,551)
Denominator:
Weighted-average number of shares used in computed net loss per share − basic	48,823,698		43,855,420		48,779,508	43,472,327
Weighted-average number of shares used in computed net loss per share − diluted	48,823,698		43,855,420		48,779,508	43,472,327
Net loss per share attributable to common stockholders − basic (in dollars per share)	$ (0.56)		$ (0.51)		$ (1.21)	$ (1.00)
Net loss per share attributable to common stockholders − diluted (in dollars per share)	$ (0.56)		$ (0.51)		$ (1.21)	$ (1.00)