Note 8 - Income Taxes (Details Textual) - USD ($)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Impairment of Investment in an Affiliated Company [Member]
Deferred Tax Assets, Valuation Allowance	$ 1,100,000
Carryforward of State RD Tax Credits [Member]
Deferred Tax Assets, Valuation Allowance	171,000
Likely To Be Recognized At December 31, 2015 [Member]
Deferred Tax Assets, Tax Credit Carryforwards, Foreign	170,000
Deferred Tax Liabilities, Undistributed Foreign Earnings	0
Deferred Tax Assets, Valuation Allowance	1,294,000	$ 1,266,000
Deferred Tax Assets, Tax Credit Carryforwards, Foreign	170,000	325,000
Undistributed Earnings of Foreign Subsidiaries	4,400,000
Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued	13,000	$ 55,000
Income Tax Examination, Penalties and Interest Expense	$ 42,000