Pension and Other Postretirement Obligations - Components of Net Periodic Benefit Costs (Detail) - USD ($) $ in Thousands	3 Months Ended
	Apr. 02, 2017	Apr. 03, 2016
Pension Obligations [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 1,093	$ 1,409
Interest cost	1,695	2,394
Expected return on plan assets	(2,361)	(3,191)
Amortization of prior service credit	(11)	(9)
Actuarial losses	587	698
Net periodic benefit cost	1,003	1,301
Other Postretirement Obligations [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	13	13
Interest cost	327	368
Expected return on plan assets	0	0
Amortization of prior service credit	0	(11)
Actuarial losses	23	82
Net periodic benefit cost	$ 363	$ 452