Consolidated Statements of Comprehensive Income (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 28, 2015	Mar. 29, 2014
Net income	$ 30,015us-gaap_NetIncomeLoss	$ 27,638us-gaap_NetIncomeLoss
Other comprehensive income (loss):
Unrealized holding gains on available-for-sale investments, net of tax expense of $125 and $60	228	110
Foreign currency translation losses	(280)	(432)
Other comprehensive loss	(52)	(322)
Comprehensive income	$ 29,963us-gaap_ComprehensiveIncomeNetOfTax	$ 27,316us-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, before reclassification adjustments, of unrealized holding gain (loss) on available-for-sale securities.

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