CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	3 Months Ended
Mar. 29, 2019	Mar. 30, 2018
Statement Of Income And Comprehensive Income [Abstract]
Net income	$ 1,367	$ 583
Defined benefit plans:
Net change in plan assets	(26)	(9)
Reclassification into other income, net	26	25
Foreign currency translation gain (loss)	(43)	728
Tax effect	20	(223)
Other comprehensive income (loss), net of tax	(23)	521
Comprehensive income	$ 1,344	$ 1,104

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Amount before tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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Amount after tax of other comprehensive income (loss) attributable to parent entity.

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Amount, before tax and reclassification adjustment, of (increase) decrease in accumulated other comprehensive income of defined benefit plan, that has not been recognized in net periodic benefit cost (credit).

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Amount, before tax, of reclassification adjustment from accumulated other comprehensive (income) loss for net period benefit cost (credit) of defined benefit plan.

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