Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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Amount 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 9 - Income Taxes (Details Textual) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Apr. 01, 2018	Apr. 02, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent				35.00%
Income Tax Expense (Benefit), Total	$ 55	$ 87
Unrecognized Tax Benefits, Ending Balance	$ 0			$ 0
Domestic Tax Authority [Member]
Operating Loss Carryforwards, Total				69,594
Tax Credit Carryforward, Amount				1,837
Domestic Tax Authority [Member] \| Earliest Tax Year [Member] \| Internal Revenue Service (IRS) [Member]
Open Tax Year	2002
Domestic Tax Authority [Member] \| Latest Tax Year [Member] \| Internal Revenue Service (IRS) [Member]
Open Tax Year	2017
Foreign Tax Authority [Member]
Operating Loss Carryforwards, Total				$ 12,760	$ 12,760
Foreign Tax Authority [Member] \| Earliest Tax Year [Member]
Open Tax Year	2009
Foreign Tax Authority [Member] \| Latest Tax Year [Member]
Open Tax Year	2017
Scenario, Forecast [Member]
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent			21.00%