Condensed Consolidated Statements of Changes in Convertible Preferred Stock and Stockholders' Equity (Deficit) (unaudited) - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Accumulated Deficit	Convertible Preferred Stock
Beginning Balance at Dec. 31, 2019	$ (118,603)	$ 1	$ 3,304	$ (121,908)
Temporary equity, Beginning Balance, Shares at Dec. 31, 2019					207,164,000
Temporary equity, Beginning Balance at Dec. 31, 2019					$ 129,870
Beginning Balance, Shares at Dec. 31, 2019		7,034,000
Vesting of share-based awards		88,000
Stock-based compensation	247		247
Net loss	(6,402)			(6,402)
Ending Balance at Mar. 31, 2020	(124,758)	$ 1	3,551	(128,310)
Temporary equity, Ending Balance, Shares at Mar. 31, 2020					207,164,000
Temporary equity, Ending Balance at Mar. 31, 2020					$ 129,870
Ending Balance, Shares at Mar. 31, 2020		7,122,000
Beginning Balance at Dec. 31, 2020	39,945	$ 5	191,348	(151,408)
Beginning Balance, Shares at Dec. 31, 2020		51,221,000
Vesting of share-based awards		92,000
Stock-based compensation	948		948
Net loss	(7,422)			(7,422)
Ending Balance at Mar. 31, 2021	$ 33,471	$ 5	$ 192,296	$ (158,830)
Ending Balance, Shares at Mar. 31, 2021		51,313,000