Condensed Consolidated Statements of Comprehensive Income (Loss) (Unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 13, 2019	Jul. 14, 2018	Jul. 13, 2019	Jul. 14, 2018
Statement Of Income And Comprehensive Income [Abstract]
Net income	$ 53,095	$ 45,442	$ 118,961	$ 96,689
Pension and postretirement plans:
Settlement loss		773		4,263
Net gain for the period		3,943		12,756
Amortization of prior service cost included in net income	60	35	139	61
Amortization of actuarial loss included in net income	1,177	865	2,746	1,941
Pension and postretirement plans, net of tax	1,237	5,616	2,885	19,021
Derivative instruments:
Net change in fair value of derivatives	12,140	(8,809)	2,547	1,661
(Gain) loss reclassified to net income	(945)	126	(3,123)	423
Derivative instruments, net of tax	11,195	(8,683)	(576)	2,084
Other comprehensive income (loss), net of tax	12,432	(3,067)	2,309	21,105
Comprehensive income	$ 65,527	$ 42,375	$ 121,270	$ 117,794