Consolidated Statements of Comprehensive Loss - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Net loss	$ (28,291)	$ (19,307)
Unrealized loss on securities available-for-sale	(142)	0
Comprehensive loss	(28,433)	(19,307)
Preferred stock dividend payable on Series A Convertible Preferred Stock	(24)	(24)
Comprehensive loss attributable to common stockholders	(28,457)	(22,598)
Series D Convertible Preferred Stock
Deemed dividend recognized on beneficial conversion features of Convertible Preferred Stock issuance	0	(602)
Series E Convertible Preferred Stock
Deemed dividend recognized on beneficial conversion features of Convertible Preferred Stock issuance	$ 0	$ (2,665)