Net loss per share attributable to common stockholders - Company’s Basic and Diluted Net Loss Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended						9 Months Ended
	Sep. 30, 2022	Jun. 30, 2022	Mar. 31, 2022	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Sep. 30, 2022	Sep. 30, 2021
Numerator:
Net loss	$ (27,259)	$ (28,680)	$ (29,494)	$ (23,634)	$ (41,198)	$ (10,962)	$ (85,433)	$ (75,794)
Cumulative undeclared preferred stock dividends	0			(242)			0	(2,284)
Net loss applicable to common stockholders basic	(27,259)			(23,876)			(85,433)	(78,078)
Net loss applicable to common stockholders diluted	$ (27,259)			$ (23,876)			$ (85,433)	$ (78,078)
Denominator:
Weighted-average common shares outstanding, basic (in shares)	91,105,265			73,291,288			90,686,517	36,177,105
Weighted-average common shares outstanding, diluted (in shares)	91,105,265			73,291,288			90,686,517	36,177,105
Net loss per share, basic (usd per share)	$ (0.30)			$ (0.33)			$ (0.94)	$ (2.16)
Net loss per share, diluted (usd per share)	$ (0.30)			$ (0.33)			$ (0.94)	$ (2.16)