Consolidated Statements of 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 Income [Abstract]
Net sales	$ 718,380	$ 691,875	$ 1,430,806	$ 1,379,002
Cost of sales, including warehousing and distribution expenses	519,461	504,151	1,036,772	1,004,560
Gross profit on sales	198,919	187,724	394,034	374,442
Operating, general and administrative expenses	173,717	168,286	349,331	332,701
Income from operations	25,202	19,438	44,703	41,741
Investment income	585	656	1,117	1,409
Income before provision for income taxes	25,787	20,094	45,820	43,150
Provision for income taxes	9,357	7,296	16,281	15,586
Net income	$ 16,430	$ 12,798	$ 29,539	$ 27,564
Weighted-average shares outstanding, basic and diluted	26,898,443	26,898,443	26,898,443	26,898,443
Cash dividends per share	$ 0.30	$ 0.30	$ 0.60	$ 0.60
Basic and diluted earnings per share	$ 0.61	$ 0.48	$ 1.10	$ 1.02