Note 15 - Income Taxes (Details Textual) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended	12 Months Ended
	Dec. 30, 2017	Mar. 31, 2019	Dec. 29, 2018	Dec. 30, 2017
Effective Income Tax Rate Reconciliation, Percent, Total			30.50%	920.40%
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent	35.00%		21.00%	34.00%
Income Tax Expense (Benefit), Total			$ 1,193	$ (2,255)
Effective Income Tax Rate Reconciliation, Tax Credit, Amount, Total			341	603
Effective Income Tax Rate Reconciliation, NOL Adjustments and Repatriation Taxes, Amount			730	198
Effective Income Tax Rate Reconciliation, Operating Loss Carryforwards Adjustments			700
Effective Income Tax Rate Reconciliation, Nondeductible Expense, Amount, Total			49	458
Effective Income Tax Rate Reconciliation, Deduction, Amount, Total				2,861
Foreign Income Tax Expense (Benefit), Continuing Operations, Total				400
Income Tax Expense (Benefit), Continuing Operations, Adjustment of Deferred Tax (Asset) Liability			1,000	$ 1,000
Effective Income Tax Rate Reconciliation, Repatriation of Foreign Earnings, Amount			200
Domestic Tax Authority [Member]
Operating Loss Carryforwards, Total			$ 3,600
Domestic Tax Authority [Member] | Internal Revenue Service (IRS) [Member]
Income Tax Examination, Year under Examination			2011 2012 2013 2015 2016 2017
State and Local Jurisdiction [Member]
Operating Loss Carryforwards, Total			$ 7,900
State and Local Jurisdiction [Member] | New Jersey Division of Taxation [Member]
Income Tax Examination, Year under Examination			2009 2010 2011 2012
Foreign Tax Authority [Member]
Operating Loss Carryforwards, Total			$ 300
Foreign Tax Authority [Member] | Ministry of Finance, Republic of Serbia [Member]
Dividend Tax Rate on Repatriation of Cash to Domestic Country			5.00%
Scenario, Forecast [Member]
Income Tax Expense (Benefit), Total		$ 600