Consolidated Statements of Comprehensive Income (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 30, 2013	Mar. 31, 2012
Consolidated Statements of Comprehensive Income [Abstract]
Net income	$ 20,129	$ 20,026
Other comprehensive income (loss) by component, net of tax:
Unrealized holding gains (losses) arising during period (Net of deferred taxes of $427 and $87, respectively)	607	(124)
Reclassification adjustment for gains included in net income (Net of deferred taxes of $21 and $1, respectively)	(26)	(2)
Other comprehensive income (loss), net of tax	581	(126)
Comprehensive income, net of tax	$ 20,710	$ 19,900