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Stock-Based Compensation - Stock incentive plan and other information (Details) - USD ($)	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Dec. 31, 2021	Dec. 31, 2020	Sep. 30, 2020	Sep. 17, 2020	Sep. 05, 2019	Sep. 24, 2018	Sep. 07, 2017	Aug. 25, 2016	May 15, 2015	Oct. 22, 2013	Nov. 02, 2010	Mar. 20, 2007
Stock-Based Compensation
Unrecognized stock-based compensation expense	$ 395,000		$ 395,000
Stock option
Stock-Based Compensation
Share-based payment award, options, outstanding, number	607,370		607,370		625,565	399,779
Share-based payment award, options, grants in period, gross		0	3,000	0	226,000
Minimum
Stock-Based Compensation
Share-based payment award, options, outstanding, number							400,000
General and Administrative Expenses \| Employees
Stock-Based Compensation
Allocated share-based compensation expense	$ 46,000	$ 34,000	$ 124,000	$ 101,000
Research and Development Expenses \| Employees
Stock-Based Compensation
Allocated share-based compensation expense	21,000	16,000	62,000	47,000
Consultant \| General and Administrative Expenses
Stock-Based Compensation
Allocated share-based compensation expense	47,000	49,000	141,000	147,000
Consultant \| Research and Development Expenses
Stock-Based Compensation
Allocated share-based compensation expense	$ 7,000	$ 3,000	$ 21,000	$ 10,000
Employees
Stock-Based Compensation
Share-based payment award, options, grants in period, gross			3,000
Employees \| General and Administrative Expenses
Stock-Based Compensation
Allocated share-based compensation expense			$ 5,000
2007 Stock Plan
Stock-Based Compensation
Share-based payment award, options, outstanding, number	515		515													7,143
Amended Stock Plan 2010 \| Maximum
Stock-Based Compensation
Share-based payment award, options, outstanding, number							7,000,000
Common stock, capital shares reserved for future issuance									400,000	100,000	50,000	40,000	22,858	17,143
Amended Stock Plan 2010 \| Minimum
Stock-Based Compensation
Common stock, capital shares reserved for future issuance									100,000	50,000	40,000	22,858	17,143	8,572
2010 Stock Plan
Stock-Based Compensation
Share-based payment award, options, outstanding, number	368,002		368,002												8,572
2010 Stock Plan \| Board of Directors
Stock-Based Compensation
Share-based payment award, options, outstanding, number	238,853		238,853
2020 Stock Plan
Stock-Based Compensation
Share-based payment award, options, outstanding, number								400,000