Benefit Plans (Schedule Of Benefit Plans) (Details) (USD $)	0 Months Ended	3 Months Ended
	Mar. 27, 2015	Mar. 31, 2015	Mar. 31, 2014
Defined Benefit Plan Disclosure [Line Items]
Settlement of projected benefit obligations	$ 59,000,000
Pension Costs [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost		827,000	473,000
Interest cost		1,526,000	2,169,000
Expected return on plan assets		(1,354,000)	(1,938,000)
Amortization of prior service cost/benefit		1,000	1,000
Net cost		1,000,000	705,000
Postretirement Costs [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost		4,000	19,000
Interest cost		315,000	352,000
Amortization of prior service cost/benefit		(43,000)	(47,000)
Net cost		$ 276,000	$ 324,000