Loss Per Share - Schedule of Basic and Diluted Loss Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Numerator:
Net loss	$ (21,835)	$ (10,094)	$ (44,540)	$ (24,076)
Accrual of preferred stock dividends	(5,212)	(2,201)	(10,363)	(6,531)
Net loss attributable to common stockholders	$ (27,047)	$ (12,295)	$ (54,903)	$ (30,607)
Denominator:
Weighted-average common stock outstanding	1,540,902	1,376,365	1,493,521	1,354,734
Net loss per share attributable to common stockholders	$ (17.55)	$ (8.93)	$ (36.76)	$ (22.59)