Employee Benefit Plans (Components Of Net Periodic Benefit Costs) (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 30, 2014	Mar. 31, 2013
Pension Plans and Supplemental Employee Retirement Plan, Defined Benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 7,874	$ 8,997
Interest cost	21,731	19,812
Expected return on plan assets	(34,184)	(31,832)
Prior service cost	279	437
Net loss	9,140	14,652
Net periodic benefit cost	4,840	12,066
Postretirement Healthcare Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	1,754	1,965
Interest cost	4,220	3,900
Expected return on plan assets	(2,607)	(2,384)
Prior service cost	(963)	(964)
Net loss	1,182	2,138
Net periodic benefit cost	$ 3,586	$ 4,655