Employee Benefit Plans And Other Postretirement Benefits (Schedule Of Reconciliation Of The Fair Value Measurements Using Significant Unobservable Inputs) (Details) (Pension And SERPA Benefits [Member], USD $) In Thousands, unless otherwise specified				12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009	Dec. 31, 2011 Significant Unobservable Inputs (Level 3) [Member]	Dec. 31, 2010 Significant Unobservable Inputs (Level 3) [Member]	Dec. 31, 2011 Significant Unobservable Inputs (Level 3) [Member] Limited Partnership Interests [Member]	Dec. 31, 2010 Significant Unobservable Inputs (Level 3) [Member] Limited Partnership Interests [Member]	Dec. 31, 2011 Significant Unobservable Inputs (Level 3) [Member] Other [Member]	Dec. 31, 2010 Significant Unobservable Inputs (Level 3) [Member] Other [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Balance, beginning of period	$ 1,253,916	$ 1,105,487	$ 1,026,124	$ 42,632	$ 32,814	$ 40,421	$ 30,332	$ 2,211	$ 2,482
Relating to assets still held at the reporting date				(2,888)	4,227	(3,018)	4,086	130	141
Purchases, sales and settlements				2,383	(5,591)	2,613	(6,003)	(230)	412
Balance, end of period	$ 1,253,916	$ 1,105,487	$ 1,026,124	$ 42,127	$ 42,632	$ 40,016	$ 40,421	$ 2,111	$ 2,211