Note 5 - Income Taxes (Details Textual) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 29, 2018	Sep. 30, 2017	Sep. 29, 2018	Sep. 30, 2017
Effective Income Tax Rate Reconciliation, Percent, Total	32.40%	17.30%	21.90%	14.00%
Effective Income Tax Rate Reconciliation, Repatriation of Foreign Earnings, Amount	$ 600		$ 600
Unrecognized Tax Benefits, Period Increase (Decrease), Total	$ 0	$ 0	$ 0	$ 0

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

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to repatriation of foreign earnings.

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Amount of increase (decrease) in unrecognized tax benefits attributable to uncertain tax positions taken in tax returns.

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