CONDENSED CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY (Unaudited) - USD ($) $ in Thousands	Total	Common Stock	Treasury Stock	Additional Paid-in Capital	Accumulated Other Comprehensive Loss	Accumulated Deficit
Beginning balance, Shares at Dec. 31, 2021		26,336,536
Beginning balance at Dec. 31, 2021	$ 72,063	$ 26	$ (51)	$ 384,132		$ (312,044)
Employee stock plans	242			242
Employee stock plans, Shares		82,572
Stock-based compensation	1,394			1,394
Net loss	(15,522)					(15,522)
Ending balance, Shares at Mar. 31, 2022		26,419,108
Ending balance at Mar. 31, 2022	58,177	$ 26	$ (51)	385,768		(327,566)
Beginning balance, Shares at Dec. 31, 2022		49,974,281
Beginning balance at Dec. 31, 2022	81,955	$ 50		451,060	$ (61)	(369,094)
Employee stock plans, Shares		216,105
Stock-based compensation	1,942			1,942
Exercised of pre-funded warrants	1	$ 1
Exercised of pre-funded warrants, Shares		1,062,080
Unrealized gain on short-term investments	56				56
Net loss	(15,371)					(15,371)
Ending balance, Shares at Mar. 31, 2023		51,252,466
Ending balance at Mar. 31, 2023	$ 68,583	$ 51		$ 453,002	$ (5)	$ (384,465)