Note 9 - Income Taxes (Details Textual) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Unrecognized Tax Benefits, Ending Balance	$ 768	$ 820	$ 848	$ 711
Deferred Tax Assets, Valuation Allowance, Total	1,744	1,824
Deferred Tax Assets, Operating Loss Carryforwards, Total	1,153	1,348
Deferred Tax Assets, Capital Loss Carryforwards	492	521
Foreign Tax Authority [Member] | AUSTRALIA
Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount	(100)	$ 400
Deferred Tax Assets, Operating Loss Carryforwards, Total	1,400
Deferred Tax Assets, Capital Loss Carryforwards	1,600
Foreign Tax Authority [Member] | FRANCE
Deferred Tax Assets, Operating Loss Carryforwards, Total	2,100
Foreign Tax Authority [Member] | SPAIN
Deferred Tax Assets, Operating Loss Carryforwards, Total	800
Foreign Tax Authority [Member] | NORWAY
Deferred Tax Assets, Operating Loss Carryforwards, Total	100
State and Local Jurisdiction [Member]
Tax Credit Carryforward, Amount	$ 1,600