Comprehensive Income (Loss) and Accumulated Other Comprehensive Income (Loss) - Summary of Effects of Reclassifications from Accumulated Other Comprehensive Income (Loss) (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
Amortization of pension and other postretirement benefit plan items:
Tax benefit	$ (5,700)	$ 21,887	$ (18,123)	$ 15,024
Net income (loss)	29,068	(38,778)	80,805	27,887
Accumulated Other Comprehensive Income (Loss), Pension and Postretirement Benefit Plans [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Amortization of pension and other postretirement benefit plan items:
Actuarial losses			5,871
Amortization of prior service credit			(105)
Total before tax			5,766
Tax benefit			(2,220)
Net income (loss)			$ 3,546