Note 8 - Income Taxes (Details Textual) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Income Tax Expense (Benefit), Total	$ 1,457	$ (18,386)
Effective Income Tax Rate Reconciliation, Change in Deferred Tax Assets Valuation Allowance, Amount		18,652
Unrecognized Tax Benefits, Ending Balance	0	$ 0
General Business Tax Credit Carryforward [Member]
Tax Credit Carryforward, Amount	1,907
Domestic Tax Authority [Member] \| Internal Revenue Service (IRS) [Member]
Operating Loss Carryforwards, Total	$ 58,400
Open Tax Year	2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2012 2013 2014 2015 2016 2017 2018 2019
Foreign Tax Authority [Member]
Open Tax Year	2010 2011 2012 2013 2014 2015 2016 2017 2018 2019
Foreign Tax Authority [Member] \| Her Majesty's Revenue and Customs (HMRC) [Member]
Operating Loss Carryforwards, Total	$ 10,600
State and Local Jurisdiction [Member]
Open Tax Year	2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2012 2013 2014 2015 2016 2017 2018 2019

Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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