Schedule of Net Periodic Pension (Benefit) Costs (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 29, 2013	Sep. 30, 2012	Sep. 29, 2013	Sep. 30, 2012
Defined Benefit Plan Disclosure
Actuarial (gain) loss			$ (1,359)	$ 4,991
Defined Benefit Pension Plans
Defined Benefit Plan Disclosure
Service cost	871	685	2,557	2,054
Interest cost	3,350	4,111	10,001	12,333
Expected return on plan assets	(3,664)	(4,090)	(10,925)	(12,269)
Amortization of unrecognized prior service cost (benefit)	41	58	123	174
Actuarial (gain) loss		1,937	(1,122)	5,083
Total net periodic (benefit) cost	598	2,701	634	7,375
Post-Retirement Benefit Plans
Defined Benefit Plan Disclosure
Service cost	19	17	56	50
Interest cost	86	109	257	328
Amortization of unrecognized prior service cost (benefit)	(150)	(150)	(449)	(449)
Actuarial (gain) loss			(236)	(92)
Total net periodic (benefit) cost	$ (45)	$ (24)	$ (372)	$ (163)