Condensed Consolidated Statements of Comprehensive Income (Loss) (Unaudited) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 24, 2016	Sep. 26, 2015	Sep. 24, 2016	Sep. 26, 2015
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ (14,198)	$ (2,525)	$ 8,887	$ (904)
Other comprehensive income (loss), net of tax:
Foreign currency translation adjustments	989	(161)	2,508	(409)
Unrealized gains on available-for-sale marketable securities	17	(7)	58	4
Unrealized losses on derivative instruments	(233)	0	(233)	0
Other comprehensive income (loss), net of tax	773	(168)	2,333	(405)
Comprehensive income (loss)	$ (13,425)	$ (2,693)	$ 11,220	$ (1,309)

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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=51831270

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

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