Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Jan. 02, 2016	Jan. 03, 2015
Statement Of Income And Comprehensive Income [Abstract]
Net income	$ 163,776	$ 189,191	$ 175,739
Pension and postretirement plans:
Settlement loss	4,087		9,463
Net loss for the period	(4,013)	(2,537)	(45,516)
Amortization of prior service credit included in net income	108	(164)	(289)
Amortization of actuarial loss included in net income	4,206	2,703	829
Pension and postretirement plans, net of tax	4,388	2	(35,513)
Derivative instruments:
Net change in fair value of derivatives	5,730	(4,195)	(3,358)
Loss reclassified to net income	3,399	5,413	3,366
Derivative instruments, net of tax	9,129	1,218	8
Other comprehensive income (loss), net of tax	13,517	1,220	(35,505)
Comprehensive income	$ 177,293	$ 190,411	$ 140,234