Condensed Consolidated Statements of Comprehensive Income (USD $) In Thousands, unless otherwise specified	3 Months Ended
Apr. 03, 2015	Apr. 04, 2014
Net income	$ 10,333us-gaap_NetIncomeLoss	$ 9,154us-gaap_NetIncomeLoss
Other comprehensive income (loss):
Foreign currency translation adjustments, net of tax	(501)	52
Unrealized (losses) gains on available-for-sale investment securities arising during the period, net of tax	(7)	14
Comprehensive income	$ 9,825us-gaap_ComprehensiveIncomeNetOfTax	$ 9,220us-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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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, before reclassification adjustments, of unrealized holding gain (loss) on available-for-sale securities.

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