Debt (Tables)

9 Months Ended

12 Months Ended

Sep. 30, 2021

Dec. 31, 2020

Debt Disclosure [Abstract]

Schedule of debt consists

	September 30, 2021			December 31, 2020
Senior secured loan, principal	$	85,987		$	63,964
Senior secured loan, paid-in-kind interest		4,231			3,554
Less unamortized discount and debt issuance costs		(8,026	)		(8,647	)
	$	82,192		$	58,871

	Year Ended December 31,
	2020			2019
	(in thousands)
Senior secured loan, principal	$	63,964		$	23,683
Senior secured loan, paid-in-kind interest		3,554			—
Less unamortized discount and debt issuance costs		(8,647	)		(7,851	)
	$	58,871		$	15,832