Fair Value Measurements (Tables)

12 Months Ended

Dec. 31, 2020

Fair Value Measurements

Summary of information about the derivative, conversion option and warrant liabilities that were measured at fair value on a recurring basis

	December 31, 2020
(in thousands)	Level 1		Level 2		Level 3		Total
Warrant liability	$	—	$	—	$	179	$	179
Total fair value	$	—	$	—	$	179	$	179

	December 31, 2019
(in thousands)	Level 1		Level 2		Level 3		Total
Warrant liability	$	—	$	—	$	3	$	3
Total fair value	$	—	$	—	$	3	$	3

Summary of change in the estimated fair value of level 3 liabilities

	Year Ended
	December 31, 2020
(in thousands)	Warrant Liability
Beginning fair value of Level 3 liability	$	3
Additions		3,696
Exercises		(6,056)
Change in fair value		2,536
Ending fair value of Level 3 liability	$	179