Consolidated Statements of Income (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
Dec. 27, 2014	Dec. 28, 2013	Dec. 29, 2012
Consolidated Statements of Income [Abstract]
Net sales	$ 2,776,683us-gaap_SalesRevenueGoodsNet	$ 2,692,588us-gaap_SalesRevenueGoodsNet	$ 2,701,405us-gaap_SalesRevenueGoodsNet
Cost of sales, including warehousing and distribution expenses	2,023,721	1,947,120	1,958,852
Gross profit on sales	752,962us-gaap_GrossProfit	745,468us-gaap_GrossProfit	742,553us-gaap_GrossProfit
Operating, general and administrative expenses	670,251us-gaap_GeneralAndAdministrativeExpense	634,286us-gaap_GeneralAndAdministrativeExpense	615,521us-gaap_GeneralAndAdministrativeExpense
Income from operations	82,711us-gaap_OperatingIncomeLoss	111,182us-gaap_OperatingIncomeLoss	127,032us-gaap_OperatingIncomeLoss
Investment income	2,287us-gaap_InvestmentIncomeNet	4,684us-gaap_InvestmentIncomeNet	3,468us-gaap_InvestmentIncomeNet
Other Income	0us-gaap_OtherIncome	0us-gaap_OtherIncome	414us-gaap_OtherIncome
Income before provision for income taxes	84,998	115,866	130,914
Provision for income taxes	29,831us-gaap_IncomeTaxExpenseBenefit	44,145us-gaap_IncomeTaxExpenseBenefit	48,403us-gaap_IncomeTaxExpenseBenefit
Net income	$ 55,167us-gaap_NetIncomeLoss	$ 71,721us-gaap_NetIncomeLoss	$ 82,511us-gaap_NetIncomeLoss
Weighted-average shares outstanding, basic and diluted	26,898,443	26,898,443	26,898,443
Cash dividends per share	$ 1.20	$ 1.20	$ 1.20
Basic and diluted earnings per share	$ 2.05us-gaap_EarningsPerShareBasicAndDiluted	$ 2.67us-gaap_EarningsPerShareBasicAndDiluted	$ 3.07us-gaap_EarningsPerShareBasicAndDiluted

Aggregate dividends declared during the period for each share of common stock outstanding.

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