CONDENSED STATEMENT OF STOCKHOLDERS' EQUITY - USD ($) shares in Thousands, $ in Thousands	Total	Preferred Stock	Common Stock	Additional Paid-In Capital	Service Receivable	Accumulated Other Comprehensive Loss	Accumulated Deficit
Balance, beginning (in shares) at Dec. 31, 2021		716	41,964
Balance, beginning at Dec. 31, 2021	$ 140,417	$ 1	$ 4	$ 400,503	$ (139)	$ (142)	$ (259,810)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock-based compensation	1,152			1,152
Other comprehensive gain (loss)	(606)					(606)
Issuance of common stock upon conversion of Series E Convertible Preferred Stock (in shares)		(328)	1,342
Issuance of common stock upon conversion of Series E Convertible Preferred Stock	(1)	$ (1)
Preferred stock dividend	(6)						(6)
Release of clinical trial funding commitment	139				139
Net loss	(10,993)						(10,993)
Balance, ending (in shares) at Mar. 31, 2022		388	43,306
Balance, ending at Mar. 31, 2022	130,102	$ 0	$ 4	401,655	0	(748)	(270,809)
Balance, beginning (in shares) at Dec. 31, 2021		716	41,964
Balance, beginning at Dec. 31, 2021	140,417	$ 1	$ 4	400,503	(139)	(142)	(259,810)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	(30,007)
Balance, ending (in shares) at Sep. 30, 2022		388	43,335
Balance, ending at Sep. 30, 2022	113,212	$ 0	$ 4	403,822	0	(779)	(289,835)
Balance, beginning (in shares) at Mar. 31, 2022		388	43,306
Balance, beginning at Mar. 31, 2022	130,102	$ 0	$ 4	401,655	0	(748)	(270,809)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock-based compensation	1,055			1,055
Other comprehensive gain (loss)	(234)					(234)
Preferred stock dividend	(6)						(6)
Net loss	(10,443)						(10,443)
Balance, ending (in shares) at Jun. 30, 2022		388	43,306
Balance, ending at Jun. 30, 2022	120,474	$ 0	$ 4	402,710	0	(982)	(281,258)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock-based compensation	1,037			1,037
Issuance of common stock upon exercise of stock options	75			75
Issuance of common stock upon exercise of stock options (in shares)			29
Other comprehensive gain (loss)	203					203
Preferred stock dividend	(6)						(6)
Net loss	(8,571)						(8,571)
Balance, ending (in shares) at Sep. 30, 2022		388	43,335
Balance, ending at Sep. 30, 2022	113,212	$ 0	$ 4	403,822	$ 0	(779)	(289,835)
Balance, beginning (in shares) at Dec. 31, 2022		61	44,677
Balance, beginning at Dec. 31, 2022	106,343	$ 0	$ 4	404,834		(395)	(298,100)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock-based compensation	1,064			1,064
Other comprehensive gain (loss)	319					319
Net loss	(11,223)						(11,223)
Balance, ending (in shares) at Mar. 31, 2023		61	44,677
Balance, ending at Mar. 31, 2023	96,503	$ 0	$ 4	405,898		(76)	(309,323)
Balance, beginning (in shares) at Dec. 31, 2022		61	44,677
Balance, beginning at Dec. 31, 2022	106,343	$ 0	$ 4	404,834		(395)	(298,100)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	(32,104)
Balance, ending (in shares) at Sep. 30, 2023		61	44,677
Balance, ending at Sep. 30, 2023	77,827	$ 0	$ 4	408,434		(407)	(330,204)
Balance, beginning (in shares) at Mar. 31, 2023		61	44,677
Balance, beginning at Mar. 31, 2023	96,503	$ 0	$ 4	405,898		(76)	(309,323)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock-based compensation	1,581			1,581
Other comprehensive gain (loss)	(355)					(355)
Net loss	(11,150)						(11,150)
Balance, ending (in shares) at Jun. 30, 2023		61	44,677
Balance, ending at Jun. 30, 2023	86,579	$ 0	$ 4	407,479		(431)	(320,473)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock-based compensation	955			955
Other comprehensive gain (loss)	24					24
Net loss	(9,731)						(9,731)
Balance, ending (in shares) at Sep. 30, 2023		61	44,677
Balance, ending at Sep. 30, 2023	$ 77,827	$ 0	$ 4	$ 408,434		$ (407)	$ (330,204)