Consolidated Statements of Changes in Redeemable Convertible Preferred Stock and Stockholders' Deficit - USD ($) shares in Thousands, $ in Thousands	Total	Series D Redeemable Convertible Preferred Stock [Member]	Non-redeemable Convertible Preferred Stock [Member]	Common Stock [Member]	Additional Paid-in Capital [Member]	Accumulated Deficit [Member]
Beginning balance at Dec. 31, 2020	$ (4,333)		$ 5	$ 8	$ 104,769	$ (109,115)
Beginning balance at Dec. 31, 2020		$ 4,300
Beginning balance, shares at Dec. 31, 2020			5,255	7,539
Conversion of series I-1 preferred stock, shares			(1)	465
Stock-based compensation	644				644
Net loss	(899)					(899)
Ending balance at Dec. 31, 2021	(4,588)		$ 5	$ 8	105,413	(110,014)
Ending balance at Dec. 31, 2021		4,300
Ending balance, shares at Dec. 31, 2021			5,254	8,004
Stock-based compensation	399				399
Net loss	(331)					(331)
Ending balance at Dec. 31, 2022	$ (4,520)		$ 5	$ 8	$ 105,812	$ (110,345)
Ending balance at Dec. 31, 2022		$ 4,300
Ending balance, shares at Dec. 31, 2022			5,254	8,004