Pension Plans And Other Postretirement Benefits (Schedule Of Changes In The Fair Value Of The Plans' Level 3 Assets) (Details) (USD $) In Thousands, unless otherwise specified								12 Months Ended
	Dec. 31, 2011		Dec. 31, 2010		Dec. 31, 2011 Pension Benefits [Member]	Dec. 31, 2010 Pension Benefits [Member]	Dec. 31, 2009 Pension Benefits [Member]	Dec. 31, 2011 Pension Benefits [Member] Unobservable inputs (Level 3) [Member]		Dec. 31, 2010 Pension Benefits [Member] Unobservable inputs (Level 3) [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets, Beginning Balance	$ 531,105	[1]	$ 507,064	[1]	$ 531,105	$ 507,064	$ 417,125	$ 69,399		$ 65,902
Total gains (losses) relating to assets sold during the period								4,471	[2]	79	[3]
Total unrealized gains relating to assets still held at the reporting date								(6,367)	[3]	4,537	[3]
Purchases								25,000
Sales								(19,478)		(1,119)
Fair value of plan assets, Ending Balance	$ 531,105	[1]	$ 507,064	[1]	$ 531,105	$ 507,064	$ 417,125	$ 73,025		$ 69,399

[1] See Note 17 "Pension Plans and Other Postretirement Benefits" for further discussion on fair value measurements of our pension and postretirement assets.

[2] These gains (losses) are recognized in the consolidated balance sheets and are included as changes in plan assets in the tables above.

[3] These gains are recognized in the consolidated balance sheets and are included as changes in plan assets in the tables above.