Income Taxes, Primary Factors Affecting Income Tax Rates (Details) - USD ($)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Primary Factors Affecting Income Tax Rates [Abstract]
Tax benefit at U.S. statutory rates	(21.00%)	(21.00%)
State tax benefit	(4.70%)	(4.70%)
Permanent differences	0.50%	0.80%
Other	(0.10%)	(2.20%)
Changes in valuation allowance	25.30%	27.10%
Income tax rate, total	0.00%	0.00%
Federal and Sate [Abstract]
Net operating loss carryforwards	$ 72,855,000	$ 79,191,000
Deferred tax asset valuation allowance percentage in each of the last two years	100.00%
Operating loss carryforwards expiration year	2037
Federal and state research and development credits expiration year	2035
Federal [Member]
Federal and Sate [Abstract]
Net operating loss carryforwards	$ 134,273,000
Research and development credits	2,437,000
State [Member]
Federal and Sate [Abstract]
Net operating loss carryforwards	102,003,000
Research and development credits	$ 1,282,000