Condensed Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2017	Sep. 24, 2016	Sep. 30, 2017	Sep. 24, 2016
Net income	$ 8,755	$ 179	$ 25,948	$ 950
Other comprehensive income, net of tax:
Foreign currency translation adjustments	2,570	561	9,975	2,724
Adjustments related to postretirement benefits	12	(2)	(116)	(35)
Change in unrealized gain/loss on investments	6	(3)	7	(1)
Other comprehensive income, net of tax	2,588	556	9,866	2,688
Comprehensive income	$ 11,343	$ 735	$ 35,814	$ 3,638

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

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Amount after tax, before reclassification adjustments, of unrealized holding gain (loss) on available-for-sale securities.

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