Benefit Plans - Funded Status (Detail) - USD ($) $ in Thousands	Jan. 01, 2017	Jan. 03, 2016	Dec. 28, 2014
Defined Benefit Plan Disclosure [Line Items]
Plan assets at fair value	$ 227,549	$ 213,378
Pension and postretirement benefit obligations	126,679	115,197
Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligation	(273,148)	(261,469)	$ (279,669)
Plan assets at fair value	228,256	214,055	212,692
Net funded status	(44,892)	(47,414)
Pension and postretirement benefit obligations	44,892	47,414
Total liability - postretirement benefits	44,892	47,414
Postretirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligation	(85,255)	(70,361)	$ (70,121)
Current liabilities	3,468	3,401
Pension and postretirement benefit obligations	81,787	66,960
Total liability - postretirement benefits	$ 85,255	$ 70,361