Note 6 - Domestic and Foreign Income Taxes (Details Textual) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount	$ (618)	$ (790)
Unrecognized Tax Benefits, Period Increase (Decrease), Total	0	0
Unrecognized Tax Benefits, Ending Balance	$ 0	0
Open Tax Year	2003 2004 2005 2009 2008 2010 2011 2012 2013 2015 2016 2017 2018
Income Tax Examination, Penalties and Interest Accrued, Total	$ 0	$ 0
Domestic Tax Authority [Member]
Operating Loss Carryforwards, Total	35,933
State and Local Jurisdiction [Member]
Operating Loss Carryforwards, Total	$ 14,381