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Amount of cash inflow from exercise of option under share-based payment arrangement.

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Number of options outstanding, including both vested and non-vested options.

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Stock-Based Compensation and Warrants - Stock incentive plan and other information (Details) - USD ($)			12 Months Ended
	Sep. 05, 2019	Nov. 02, 2010	Dec. 31, 2022	Dec. 31, 2021	Sep. 17, 2020	Mar. 20, 2007
Stock-Based Compensation and Warrants
Unrecognized stock-based compensation expense			$ 997,000
Proceeds from Stock Options Exercised			0	$ 0
General and Administrative Expenses and Research and Development Expense \| Employees
Stock-Based Compensation and Warrants
Allocated share-based compensation expense			$ 260,000	$ 204,000
Employees And Directors
Stock-Based Compensation and Warrants
Share-based payment award, options, grants in period, gross			1,728,000	2,260,000
Consultant \| General and Administrative Expenses and Research and Development Expense
Stock-Based Compensation and Warrants
Allocated share-based compensation expense			$ 215,000	$ 212,000
Employees \| General and Administrative Expenses and Research and Development Expense
Stock-Based Compensation and Warrants
Allocated share-based compensation expense			$ 700,000	$ 500,000
2007 Stock Plan
Stock-Based Compensation and Warrants
Share-based payment award, options, outstanding, number			515			7,143
2010 Stock Plan
Stock-Based Compensation and Warrants
Share-based payment award, options, outstanding, number		8,572
Share-based compensation arrangement by share-based payment award, number of shares authorized	400,000
Share-based compensation arrangement by share-based payment award, shares issued			0
2010 Stock Plan \| Board of Directors
Stock-Based Compensation and Warrants
Share-based payment award, options, outstanding, number			202,381
2010 Stock Plan \| Minimum
Stock-Based Compensation and Warrants
Share-based payment award, options, grants, expired period		5 years
2010 Stock Plan \| Maximum
Stock-Based Compensation and Warrants
Share-based payment award, options, grants, expired period		10 years
2020 Stock Plan
Stock-Based Compensation and Warrants
Share-based payment award, options, outstanding, number			2,093,002		400,000
Share-based compensation arrangement by share-based payment award, number of shares authorized			7,000,000