Pension And Other Postretirement Benefits (Schedule Of Net Benefit Cost Of Pension And Postretirement Benefit Plans) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2011		Dec. 31, 2010		Dec. 31, 2009
Pension [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 2,297	[1]	$ 2,229	[1]	$ 2,152	[1]
Interest cost	17,284	[1]	17,141	[1]	17,116	[1]
Expected return on plan assets	(19,998)	[1]	(16,753)	[1]	(13,782)	[1]
Net amortization and deferral	4,018	[1]	4,013	[1]	4,226	[1]
Curtailment gain	(37)	[1]	(52)	[1]
Settlement gain	(5)	[1]	(40)	[1]
Special termination costs					343	[1]
Net benefit cost	3,559	[1]	6,538	[1]	10,055	[1]
Other Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	479	[1]	690	[1]	670	[1]
Interest cost	2,054	[1]	2,310	[1]	2,802	[1]
Net amortization and deferral	(45)	[1]	105	[1]	387	[1]
Special termination costs					395	[1]
Net benefit cost	$ 2,488	[1]	$ 3,105	[1]	$ 4,254	[1]

[1] All periods have been adjusted to remove amounts related to discontinued operations.