Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 27, 2015	Jun. 28, 2014	Jun. 27, 2015	Jun. 28, 2014
Consolidated Statements of Comprehensive Income [Abstract]
Net income	$ 16,430	$ 12,798	$ 29,539	$ 27,564
Other comprehensive income (loss) by component, net of tax:
Unrealized holding gains (losses) arising during period (Net of deferred taxes of $88 and $162, respectively for the 13 Weeks Ended and $76 and $819, respectively for the 26 Weeks Ended)	(127)	235	(109)	1,168
Reclassification adjustment for gains included in net income (Net of deferred taxes of $4 and $2, respectively for the 13 Weeks Ended and $7 and $20, respectively for the 26 Weeks Ended)	(5)	(3)	(8)	(26)
Other comprehensive income (loss), net of tax	(132)	232	(117)	1,142
Comprehensive income, net of tax	$ 16,298	$ 13,030	$ 29,422	$ 28,706