CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 28, 2015	Mar. 29, 2014
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ 12,366us-gaap_NetIncomeLoss	$ (4,374)us-gaap_NetIncomeLoss
Other comprehensive income (loss):
Unrealized gain on all other available-for-sale investments	267	50
Foreign currency translation adjustment	(159)	244
Tax related to available-for-sale investment	0	(20)
Net change in accumulated other comprehensive income	108	274
Comprehensive income (loss)	$ 12,474us-gaap_ComprehensiveIncomeNetOfTax	$ (4,100)us-gaap_ComprehensiveIncomeNetOfTax

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 appreciation (loss) in value of unsold available-for-sale securities. Excludes amounts related to other than temporary impairment (OTTI) loss.

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Amount of tax expense (benefit), after reclassification adjustments, of appreciation (loss) in value of unsold available-for-sale securities. Excludes amounts related to other than temporary impairment (OTTI) 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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