Components of Pension Cost (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 04, 2015	Jun. 28, 2014	Jul. 04, 2015	Jun. 28, 2014
Defined Benefit Plan Disclosure [Line Items]
Service cost - benefits earned during the period	$ 7,344	$ 6,097	$ 14,679	$ 12,182
Interest cost on projected benefit obligations	19,411	20,404	38,814	40,793
Expected return on plan assets	(27,779)	(22,697)	(55,550)	(45,378)
Amortization of deferred amounts, Net deferred actuarial losses	15,495	9,389	30,992	18,773
Amortization of deferred amounts, Deferred prior service costs	759	1,362	1,521	2,724
Net periodic pension cost	$ 15,230	$ 14,555	$ 30,456	$ 29,094