Consolidated Statements of Comprehensive Income (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 27, 2014	Dec. 28, 2013	Dec. 29, 2012
Consolidated Statements of Comprehensive Income [Abstract]
Net income	$ 55,167us-gaap_NetIncomeLoss	$ 71,721us-gaap_NetIncomeLoss	$ 82,511us-gaap_NetIncomeLoss
Other comprehensive income (loss) by component, net of tax:
Unrealized holding gains (losses) arising during period (Net of deferred taxes of $644, $23 and $0, respectively)	927	(36)	(9)
Reclassification adjustment for gains included in net income (Net of deferred taxes of $26, $730 and $293, respectively)	(37)	(1,044)	(420)
Other comprehensive income (loss), net of tax	890	(1,080)	(429)
Comprehensive income, net of tax	$ 56,057us-gaap_ComprehensiveIncomeNetOfTax	$ 70,641us-gaap_ComprehensiveIncomeNetOfTax	$ 82,082us-gaap_ComprehensiveIncomeNetOfTax

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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