Summary of Quarterly Financial Data (Unaudited) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 24, 2016	Jun. 25, 2016	Mar. 26, 2016	Dec. 26, 2015	Sep. 26, 2015	Jun. 27, 2015	Mar. 28, 2015	Dec. 31, 2016	Dec. 26, 2015	Dec. 27, 2014
Summary of Quarterly Results [Abstract]
Net sales	$ 925,097	$ 742,986	$ 730,433	$ 738,204	$ 734,063	$ 711,879	$ 718,380	$ 712,426	$ 3,136,720	$ 2,876,748	$ 2,776,683
Gross profit on sales	258,241	204,864	201,938	207,112	198,551	194,147	198,919	195,115	872,155	786,732	752,962
Gain on bargain purchase	23,879	0	0	0					23,879	0	0
Net income	$ 41,140	$ 10,628	$ 15,265	$ 20,129	$ 16,575	$ 12,788	$ 16,644	$ 13,323	$ 87,162	$ 59,330	$ 54,381
Basic and diluted earnings per share	$ 1.52	$ 0.40	$ 0.57	$ 0.75	$ 0.61	$ 0.48	$ 0.62	$ 0.50	$ 3.24	$ 2.21	$ 2.02