Note 11 - Income Taxes - Income Tax Reconciliation (Details) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Income taxes based on U.S. statutory rate of 21% and 34%, respectively	$ 773,000	$ 928,000
Non-deductible meals and entertainment	8,000	5,000
FDII deduction	(6,000)	(56,000)
Foreign taxes	(75,000)	(123,000)
State taxes	85,000	89,000
Other	(105,000)	(54,000)
Provision for income taxes	$ 680,000	$ 789,000