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 income	$ 57,919	$ 53,095	$ 52,147	$ 118,961
Pension and postretirement plans:
Settlement and curtailment loss			86,865
Net gain for the period			15,693
Amortization of prior service cost included in net income	9	60	64	139
Amortization of actuarial loss included in net income	43	1,177	996	2,746
Pension and postretirement plans, net of tax	52	1,237	103,618	2,885
Derivative instruments:
Net change in fair value of derivatives	(3,358)	12,140	(7,207)	2,547
Loss (gain) reclassified to net income	664	(945)	1,075	(3,123)
Derivative instruments, net of tax	(2,694)	11,195	(6,132)	(576)
Other comprehensive income (loss), net of tax	(2,642)	12,432	97,486	2,309
Comprehensive income	$ 55,277	$ 65,527	$ 149,633	$ 121,270