Stockholders' Equity - Warrants (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	Nov. 08, 2019
Warrants and Rights Note Disclosure [Abstract]
Warrants outstanding	4,003,642		4,003,642		12,666,666
Common stock for each warrant exercised					1
Warrant exercisable price					$ 11.50
Warrants exercised in cashless transaction, number exercised			52,785	0
Shares issued in cashless exercise of warrants (in shares)			18,667
Warrant liability, beginning			$ 57,764	$ 113,905
Change in fair value of warrant liability (note 10)	$ 8,208	$ (37,454)	(18,509)	(40,622)
Reclassification of warrant liability to equity for exercised warrants	(495)		(495)
Warrant liability, ending	$ 38,760	$ 73,283	$ 38,760	$ 73,283