Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 29, 2018	Jun. 30, 2017	Jun. 29, 2018	Jun. 30, 2017
Statement of Comprehensive Income [Abstract]
Net income	$ 11,144	$ 7,313	$ 21,708	$ 10,363
Other comprehensive income (loss):
Foreign currency translation adjustment	(944)	275	169	1,378
Derivative and hedging activity, net of tax	1,763	(174)	1,088	(635)
Pension and post-employment benefit adjustment, net of tax	1,296	759	2,574	1,516
Net current period other comprehensive income (loss) after tax	2,115	860	3,831	2,259
Comprehensive income	$ 13,259	$ 8,173	$ 25,539	$ 12,622

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 after tax and reclassification adjustments, of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

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Amount after 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 and reclassification adjustments of other comprehensive income (loss).

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Amount, after tax and reclassification adjustment, of (increase) decrease in accumulated other comprehensive income for defined benefit plan.

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