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 Comprehensive Income [Abstract]
Net income	$ 9,926	$ 16,973	$ 33,397	$ 39,390
Other comprehensive loss – unrealized loss on available-for-sale marketable debt securities, net of income tax	(38)	(26)	(45)	(38)
Comprehensive income	$ 9,888	$ 16,947	$ 33,352	$ 39,352