Net loss per share - Basic and Diluted EPS (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Net loss per share
Basic net income (loss) per share (in dollars per share)	$ (2.04)	$ (1.90)	$ (4.23)	$ (4.18)
Diluted net income (loss) per share (in dollars per share)	$ (2.04)	$ (1.90)	$ (4.23)	$ (4.18)
Basic and Diluted net loss per share - Numerator
Net income (loss), Basic	$ (39,949)	$ (36,421)		$ (43,733)
Net income (loss), Diluted	$ (39,949)	$ (36,421)	$ (82,383)	$ (80,154)
Denominator - Weighted average number of shares outstanding
Weighted Average Number of Shares Outstanding, Basic	19,585,164	19,200,747	19,482,943	19,196,798
Diluted net income (loss) per share (in dollars per share)	$ (2.04)	$ (1.90)	$ (4.23)	$ (4.18)