CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 28, 2013	Sep. 29, 2012	Sep. 28, 2013	Sep. 29, 2012
Statement Of Income And Comprehensive Income [Abstract]
Net income	$ 38,600	$ 27,097	$ 92,708	$ 87,914
Other comprehensive income (loss):
Unrealized gains (losses) on hedging transactions, net of income taxes	(1,007)	(3,946)	345	(6,192)
Unrealized holding gains (losses) on investments, net of income taxes	433	392	(506)	917
Foreign currency translation adjustment	182	12	499	198
Comprehensive income	$ 38,208	$ 23,555	$ 93,046	$ 82,837