Condensed Consolidated Statements of Income (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 16, 2016	Jul. 18, 2015	Jul. 16, 2016	Jul. 18, 2015
Income Statement [Abstract]
Sales	$ 935,025	$ 888,795	$ 2,139,377	$ 2,034,840
Materials, supplies, labor and other production costs (exclusive of depreciation and amortization shown separately below)	477,955	457,253	1,099,145	1,043,169
Selling, distribution and administrative expenses	338,396	318,758	782,935	742,532
Impairment of assets		2,275		2,275
Pension plan settlement loss	4,641		4,641
Depreciation and amortization	32,598	30,468	76,065	70,285
Income from operations	81,435	80,041	176,591	176,579
Interest expense	7,649	5,998	16,717	14,357
Interest income	(4,639)	(5,138)	(10,929)	(11,915)
Income before income taxes	78,425	79,181	170,803	174,137
Income tax expense	27,270	27,421	60,285	60,988
Net income	$ 51,155	$ 51,760	$ 110,518	$ 113,149
Basic:
Net income per common share	$ 0.25	$ 0.25	$ 0.53	$ 0.54
Weighted average shares outstanding	207,211	210,334	209,183	210,093
Diluted:
Net income per common share	$ 0.24	$ 0.24	$ 0.52	$ 0.53
Weighted average shares outstanding	209,014	212,872	211,230	212,798
Cash dividends paid per common share	$ 0.1600	$ 0.1450	$ 0.3050	$ 0.2775