CONDENSED CONSOLIDATED STATEMENTS OF STOCKHOLDERS' DEFICIT - USD ($) $ in Thousands	Total	Preferred stock	Common stock	Common stock Nonrelated Party	Common stock Related Party	Contributed capital	Contributed capital Nonrelated Party	Contributed capital Related Party	Accumulated deficit	Treasury stock	Accumulated other comprehensive loss
Beginning balance (in shares) at Dec. 31, 2022		3,955,000
Ending balance (in shares) at Mar. 31, 2023		3,955,000
Beginning balance (in shares) at Dec. 31, 2022			9,748,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Restricted stock awards released (in shares)			215,000
Ending balance (in shares) at Mar. 31, 2023			9,963,000
Beginning balance at Dec. 31, 2022		$ 4	$ 10			$ 630,428			$ (607,239)	$ (45,067)	$ (400)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Equity-based compensation						562
Reclassification of common stock par value due to reverse stock split						3
Net loss	$ (16,795)								(16,795)
Net unrealized gain on debt securities available-for-sale	24										24
Foreign currency translation adjustment	(255)										(255)
Ending balance at Mar. 31, 2023	$ (38,725)	$ 4	$ 10			630,993			(624,034)	(45,067)	(631)
Beginning balance (in shares) at Dec. 31, 2023	0	0
Ending balance (in shares) at Mar. 31, 2024	0	0
Beginning balance (in shares) at Dec. 31, 2023	14,569,500		14,570,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of stock (in shares)				5,766,000	1,189,000
Restricted stock awards released (in shares)			276,000
Issuance of shares to retire convertible notes and derivative (in shares)			11,000
Ending balance (in shares) at Mar. 31, 2024	21,811,706		21,812,000
Beginning balance at Dec. 31, 2023	$ (19,888)	$ 0	$ 14			694,634			(668,857)	(45,067)	(612)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock				$ 6	$ 1		$ 4,367	$ 1,593
Pre-funded warrants, net issuance costs						1,077
Issuance of shares to retire convertible notes						43
Equity-based compensation						1,257
Net loss	(14,230)								(14,230)
Net unrealized gain on debt securities available-for-sale	0
Foreign currency translation adjustment	(6)										(6)
Ending balance at Mar. 31, 2024	$ (25,780)	$ 0	$ 21			$ 702,971			$ (683,087)	$ (45,067)	$ (618)