CONDENSED CONSOLIDATED STATEMENTS OF REDEEMABLE PREFERRED STOCK AND STOCKHOLDERS' EQUITY (UNAUDITED) - USD ($) $ in Thousands	Common Stock	Preferred Stock Series Z preferred stock	Preferred Stock Series B Preferred Stock	Additional Paid-In Capital	Accumulated Deficit	Other Comprehensive Income (Loss)	Total
Beginning balance at Dec. 31, 2021	$ 3			$ 764,911	$ (735,461)		$ 29,453
Beginning balance (in shares) at Dec. 31, 2021	3,106,947
Increase (Decrease) in Stockholders' Equity
Sale of common stock, net of issuance costs				(15)			(15)
Issuance of common stock under employee stock purchase plan				16			16
Issuance of common stock under employee stock purchase plan (in shares)	2,482
Issuance of common stock under equity incentive plan upon vesting of restricted stock units (in shares)	1,600
Issuance of common stock for services rendered				22			22
Issuance of common stock for services rendered (in shares)	2,180
Stock-based compensation expense				545			545
Net loss					(4,178)		(4,178)
Ending balance at Mar. 31, 2022	$ 3			765,479	(739,639)		25,843
Ending balance (in shares) at Mar. 31, 2022	3,113,209
Temporary equity, Beginning balance at Dec. 31, 2022		$ 27,108
Temporary equity, Beginning balance (in shares) at Dec. 31, 2022		77,900
Increase (Decrease) in Temporary Equity
Vesting of restricted stock awards (in shares)		47
Conversion of preferred stock to common stock		$ (27,108)
Conversion of preferred stock to common, shares		(77,947)
Beginning balance at Dec. 31, 2022	$ 4		$ 1	770,663	(758,821)	$ (21)	$ 11,826
Beginning balance at Dec. 31, 2022			62,355
Beginning balance (in shares) at Dec. 31, 2022	3,653,685						3,653,685
Increase (Decrease) in Stockholders' Equity
Vesting of restricted stock awards (in shares)	6,386
Issuance of common stock under equity incentive plan upon vesting of restricted stock units and exercise of options				88			$ 88
Issuance of common stock under equity incentive plan upon vesting of restricted stock units and exercise of options (in shares)	55,891
Issuance of common stock under equity incentive plan for retention payments				456			456
Issuance of common stock under equity incentive plan for retention payments (in shares)	43,900
Issuance of common stock for services rendered				15			15
Issuance of common stock for services rendered (in shares)	1,972
Conversion of preferred stock to common stock	$ 4		$ (1)	27,105			27,108
Conversion of preferred stock to common stock (in shares)	4,585,115		(62,355)
Reclassification of warrant liability upon conversion of Series Z Preferred Stock warrants to common stock warrants				3,693			3,693
Stock-based compensation expense				1,231			1,231
Foreign currency translation						(2)	(2)
Net loss					(21,867)		(21,867)
Ending balance at Mar. 31, 2023	$ 8			$ 803,251	$ (780,688)	$ (23)	$ 22,548
Ending balance (in shares) at Mar. 31, 2023	8,346,949						8,346,949