CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Unaudited) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jul. 11, 2020	Jul. 13, 2019	Jul. 11, 2020	Jul. 13, 2019
Statement Of Income And Comprehensive Income [Abstract]
Net earnings (loss)	$ 28,467	$ (6,814)	$ 43,869	$ 655
Other comprehensive income, before tax
Pension and postretirement liability adjustment	27	8,937	133	9,016
Income tax expense related to items of other comprehensive income	(7)	(2,170)	(33)	(2,189)
Total other comprehensive income, after tax	20	6,767	100	6,827
Comprehensive income (loss)	$ 28,487	$ (47)	$ 43,969	$ 7,482

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount after tax of other comprehensive income (loss) attributable to parent entity.

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