CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Thousands	3 Months Ended						4 Months Ended		12 Months Ended
	Dec. 28, 2019	Oct. 05, 2019	Jul. 13, 2019	Dec. 29, 2018	Oct. 06, 2018	Jul. 14, 2018	Apr. 20, 2019	Apr. 21, 2018	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Net sales	$ 2,112,614	$ 2,312,106	$ 2,332,246	$ 2,105,072	$ 2,274,982	$ 2,326,652	$ 2,952,036	$ 2,873,848	$ 9,709,003	$ 9,580,554	$ 9,373,784
Cost of sales, including purchasing and warehousing costs									5,454,257	5,361,141	5,288,735
Gross profit	928,769	1,011,926	1,009,438	928,643	1,006,927	1,011,559	1,304,612	1,272,284	4,254,746	4,219,413	4,085,049
Selling, general and administrative expenses									3,577,566	3,615,138	3,514,837
Operating income									677,180	604,275	570,212
Other, net:
Interest expense									(39,898)	(56,588)	(58,801)
Other income, net									464	7,577	8,848
Total other, net									(39,434)	(49,011)	(49,953)
Income before provision for income taxes									637,746	555,264	520,259
Provision for income taxes									150,850	131,417	44,754
Net income	$ 95,907	$ 123,669	$ 124,820	$ 53,441	$ 115,843	$ 117,836	$ 142,500	$ 136,727	$ 486,896	$ 423,847	$ 475,505
Basic earnings per common share	$ 1.39	$ 1.76	$ 1.74	$ 0.74	$ 1.57	$ 1.59	$ 1.99	$ 1.85	$ 6.87	$ 5.75	$ 6.44
Weighted average common shares outstanding									70,869	73,728	73,846
Diluted earnings per common share	$ 1.38	$ 1.75	$ 1.73	$ 0.74	$ 1.56	$ 1.59	$ 1.98	$ 1.84	$ 6.84	$ 5.73	$ 6.42
Weighted average common shares outstanding									71,165	73,991	74,110