UNAUDITED CONDENSED CONSOLIDATED STATEMENTS OF CONVERTIBLE PREFERRED STOCK AND STOCKHOLDERS' EQUITY (DEFICIT) - USD ($) $ in Thousands	Total	Series A Convertible Preferred Stock	Series B Convertible Preferred Stock	Series C Convertible Preferred Stock	Common Stock	Additional Paid-in Capital	Additional Paid-in Capital Series A Convertible Preferred Stock	Accumulated Deficit	Accumulated Deficit Series A Convertible Preferred Stock	Accumulated Deficit Series B Convertible Preferred Stock	Accumulated Deficit Series C Convertible Preferred Stock
Beginning balance at Dec. 31, 2019	$ (422,862)							$ (422,862)
Convertible Preferred Stock, beginning balance, Shares at Dec. 31, 2019	318,510,205
Convertible Preferred Stock, beginning balance at Dec. 31, 2019	$ 411,275
Beginning balance, shares at Dec. 31, 2019					7,787,470
Net income (loss)	(38,620)							(38,620)
Preferred stock dividend		$ (8,844)	$ (302)	$ (1,299)			$ (519)		$ (8,325)	$ (302)	$ (1,299)
Preferred stock accretion		(776)	(6)	(140)					$ (776)	$ (6)	$ (140)
Temporary equity, Preferred stock dividend		8,844	302	1,299
Temporary equity, Preferred stock accretion		$ 776	$ 6	$ 140
Exercise of stock options	151					$ 151
Exercise of stock options, Shares					18,378
Stock-based compensation	368					368
Ending balance at Mar. 31, 2020	$ (472,330)							(472,330)
Convertible Preferred Stock, Ending balance, Shares at Mar. 31, 2020	318,510,205	285,000,000	8,000,000	25,510,205
Convertible Preferred Stock, ending balance at Mar. 31, 2020	$ 422,642
Ending balance, shares at Mar. 31, 2020					7,805,848
Beginning balance at Dec. 31, 2020	97,180				$ 1	585,374		(488,195)
Beginning balance, shares at Dec. 31, 2020					56,890,569
Net income (loss)	7,386							7,386
Exercise of stock options	$ 12					12
Exercise of stock options, Shares	1,837				1,837
Stock-based compensation	$ 3,301					3,301
Ending balance at Mar. 31, 2021	$ 107,879				$ 1	$ 588,687		$ (480,809)
Ending balance, shares at Mar. 31, 2021					56,892,406