Note B - Marketable Securities (Details Textual) - USD ($)		12 Months Ended
	Jan. 01, 2018	Dec. 31, 2019	Dec. 31, 2018
Reclassification of Unrealized Gain (Loss) on Securities from AOCI to Retained Earnings
Proceeds from Sale and Maturity of Marketable Securities, Total		$ 15,964,917	8,022,804
Debt and Equity Securities, Realized Gain (Loss), Total		$ 262,399	4,204
AOCI Attributable to Parent [Member]
Reclassification of Unrealized Gain (Loss) on Securities from AOCI to Retained Earnings			$ (466,025)
AOCI Attributable to Parent [Member] | Accounting Standards Update 2016-01 [Member]
Reclassification of Unrealized Gain (Loss) on Securities from AOCI to Retained Earnings	$ (466,025)