Condensed Consolidated Statements of Comprehensive Income (Loss) (Unaudited) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Oct. 05, 2019	Oct. 06, 2018	Oct. 05, 2019	Oct. 06, 2018
Statement Of Income And Comprehensive Income [Abstract]
Net income	$ 43,358	$ 39,630	$ 162,319	$ 136,319
Pension and postretirement plans:
Settlement loss		696		4,959
Net loss for the period		(32,639)		(19,883)
Amortization of prior service cost included in net income	59	35	198	96
Amortization of actuarial loss included in net income	1,177	768	3,923	2,709
Pension and postretirement plans, net of tax	1,236	(31,140)	4,121	(12,119)
Derivative instruments:
Net change in fair value of derivatives	(7,124)	7,394	(4,577)	9,055
Loss (gain) reclassified to net income	259	266	(2,864)	689
Derivative instruments, net of tax	(6,865)	7,660	(7,441)	9,744
Other comprehensive loss, net of tax	(5,629)	(23,480)	(3,320)	(2,375)
Comprehensive income	$ 37,729	$ 16,150	$ 158,999	$ 133,944

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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