Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
	Jan. 02, 2016	Jan. 03, 2015	Dec. 28, 2013
Statement Of Income And Comprehensive Income [Abstract]
Net income	$ 189,191	$ 175,739	$ 230,894
Pension and postretirement plans:
Prior service credit for the period			682
Settlement loss		9,463
Net (loss) gain for the period	(2,537)	(45,516)	55,637
Amortization of prior service credit included in net income	(164)	(289)	(158)
Amortization of actuarial loss included in net income	2,703	829	3,307
Pension and postretirement plans, net of tax	2	(35,513)	59,468
Derivative instruments:
Net change in fair value of derivatives	(4,195)	(3,358)	(24,457)
Loss reclassified to net income	5,413	3,366	17,141
Derivative instruments, net of tax	1,218	8	(7,316)
Other comprehensive income (loss), net of tax	1,220	(35,505)	52,152
Comprehensive income	$ 190,411	$ 140,234	$ 283,046