Employee Benefit Plans (Components Of Net Periodic Benefit Costs) (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Apr. 01, 2012
Pension And SERPA Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 8,997	$ 8,420
Interest cost	19,812	20,816
Expected return on plan assets	(31,832)	(29,277)
Prior service cost	437	740
Net loss	14,652	10,969
Net periodic benefit cost	12,066	11,668
Postretirement Healthcare Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	1,965	1,853
Interest cost	3,900	4,578
Expected return on plan assets	(2,384)	(2,356)
Prior service cost	(964)	(963)
Net loss	2,138	1,855
Net periodic benefit cost	$ 4,655	$ 4,967