Consolidated Statements of Comprehensive Income (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 29, 2014	Mar. 30, 2013
Statement of Comprehensive Income [Abstract]
Net income	$ 16,992	$ 23,471
Other comprehensive income (loss) – unrealized gain (loss) on available-for-sale marketable debt securities, net of income tax	10	(7)
Comprehensive income	$ 17,002	$ 23,464