CONDENSED CONSOLIDATED STATEMENTS OF EARNINGS (Unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 11, 2020	Jul. 13, 2019	Jul. 11, 2020	Jul. 13, 2019
Income Statement [Abstract]
Net sales	$ 2,184,101	$ 1,995,929	$ 5,040,557	$ 4,538,304
Cost of sales	1,845,727	1,706,922	4,278,616	3,871,568
Gross profit	338,374	289,007	761,941	666,736
Operating expenses
Selling, general and administrative	300,727	266,474	692,027	626,874
Merger/acquisition and integration		582		1,364
Restructuring charges and asset impairment	3,675	14,581	13,912	8,919
Total operating expenses	304,402	281,637	705,939	637,157
Operating earnings	33,972	7,370	56,002	29,579
Other expenses and (income)
Interest expense	3,650	8,696	11,288	20,577
Postretirement benefit expense (income)	101	8,821	(698)	9,456
Other, net	(164)	(439)	(406)	(891)
Total other expenses, net	3,587	17,078	10,184	29,142
Earnings (loss) before income taxes and discontinued operations	30,385	(9,708)	45,818	437
Income tax expense (benefit)	1,918	(2,941)	1,949	(317)
Earnings (loss) from continuing operations	28,467	(6,767)	43,869	754
Loss from discontinued operations, net of taxes		(47)		(99)
Net earnings (loss)	$ 28,467	$ (6,814)	$ 43,869	$ 655
Basic and diluted earnings (loss) per share:
Earnings (loss) from continuing operations	$ 0.80	$ (0.19)	$ 1.22	$ 0.02
Net earnings (loss)	$ 0.80	$ (0.19)	$ 1.22	$ 0.02