Note L - Income Taxes (Details Textual) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Operating Loss Carryforwards, Valuation Allowance, Total	$ 0	$ 0
Operating Loss Carryforwards, Expired	$ 3,400,000	4,500,000
Percentage of Valuation Allowance	100.00%
Effective Income Tax Rate Reconciliation, State and Local Income Taxes, Amount	$ 24,000	18,000
Unrecognized Tax Benefits, Ending Balance	0	0
Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense, Total	0	0
Domestic Tax Authority [Member]
Operating Loss Carryforwards, Total	$ 66,000,000	59,000,000
Open Tax Year	2017 2018 2019
State and Local Jurisdiction [Member]
Income (Loss) from Continuing Operations before Income Taxes, Domestic	$ (56,300,000)	$ (56,700,000)
Open Tax Year	2017 2018 2019