CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 29, 2013	Jun. 30, 2012	Jun. 29, 2013	Jun. 30, 2012
Statement Of Income And Comprehensive Income [Abstract]
Net income	$ 30,566	$ 30,653	$ 54,108	$ 60,817
Other comprehensive income (loss):
Unrealized gains (losses) on hedging transactions, net of income taxes	(391)	2,400	1,352	(2,246)
Unrealized holding gains (losses) on investments, net of income taxes	(867)	(46)	(939)	524
Foreign currency translation adjustment	223	105	317	188
Comprehensive income	$ 29,531	$ 33,112	$ 54,838	$ 59,283