Benefit Plans - Reconciliation of Beginning and Ending Balances of Benefit Obligation (Detail) - USD ($) $ in Thousands	12 Months Ended
	Jan. 03, 2016	Dec. 28, 2014	Dec. 29, 2013
Defined Benefit Plan Disclosure [Line Items]
Benefit obligation at beginning of year	$ 279,669
Benefit obligation at end of year	261,469	$ 279,669
Postretirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Benefit obligation at beginning of year	70,121	67,840
Service cost	1,118	1,445	$ 1,626
Interest cost	2,878	3,255	2,877
Plan amendments	0	(8,681)
Plan participants’ contributions	594	586
Actuarial (gain)/loss	(1,600)	9,323
Benefits paid	(2,886)	(3,685)
Medicare Part D subsidy reimbursement	136	38
Benefit obligation at end of year	$ 70,361	$ 70,121	$ 67,840