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

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Tax year that remains open to examination under enacted tax laws, in CCYY format.

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Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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Amount of unrecognized tax benefits.

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Note 8 - Income Taxes (Details Textual) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Apr. 01, 2018	Dec. 31, 2018
Effective Income Tax Rate Reconciliation, Percent, Total	8.00%	3.00%
Operating Loss Carryforwards, Valuation Allowance, Total	$ 10,000
Unrecognized Tax Benefits, Ending Balance	0		$ 0
General Business Tax Credit Carryforward [Member]
Tax Credit Carryforward, Amount	1,817
Domestic Tax Authority [Member] \| Internal Revenue Service (IRS) [Member]
Operating Loss Carryforwards, Total	$ 63,388
Open Tax Year	2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018
Foreign Tax Authority [Member]
Open Tax Year	2010 2011 2012 2013 2014 2015 2016 2017 2018
Foreign Tax Authority [Member] \| Her Majesty's Revenue and Customs (HMRC) [Member]
Operating Loss Carryforwards, Total	$ 0
State and Local Jurisdiction [Member]
Open Tax Year	2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018