Pension and Postretirement Benefit Obligations - Components of Net Periodic Pension Cost (Detail) - Pension Plans [Member] - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 01, 2018	Jul. 02, 2017	Jul. 01, 2018	Jul. 02, 2017
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 1,413	$ 150	$ 2,825	$ 300
Interest cost	2,856	2,979	5,712	5,958
Expected return on plan assets	(3,852)	(3,399)	(7,704)	(6,798)
Recognized net actuarial loss	933	807	1,866	1,614
Amortization of prior service cost	6	7	12	14
Net periodic pension cost	$ 1,356	$ 544	$ 2,711	$ 1,088