Net Loss per Share Attributable to Common Stock - Computation of Net Loss Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Numerator:
Net loss	$ (35,784)	$ (60,117)
Dividends on convertible preferred stock	(2,336)	0
Net loss attributable to common stock - basic	(38,120)	(60,117)
Net loss attributable to common stock - diluted	$ (38,120)	$ (60,117)
Denominator:
Weighted average shares - basic (in shares)	103,427,764	93,442,706
Weighted averages shares - diluted (in shares)	103,427,764	93,442,706
Earnings Per Share, Basic and Diluted [Abstract]
Net loss per share attributable to common stock - basic (in dollars per share)	$ (0.37)	$ (0.64)
Net loss per share attributable to common stock - diluted (in dollars per share)	$ (0.37)	$ (0.64)