Employee Benefit Plans And Other Postretirement Benefits (Components Of Net Periodic Benefit Costs) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Pension And SERPA Benefits [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Service cost	$ 33,681	$ 37,341	$ 42,889
Interest cost	83,265	80,805	77,996
Expected return on plan assets	(117,110)	(106,612)	(97,376)
Prior service cost (credit)	2,958	2,981	4,383
Net loss	43,874	30,266	23,872
Net curtailment loss	0	236	15,508
Settlement loss	6,242	274	4,673
Net periodic benefit cost	52,910	45,291	71,945
Postretirement Healthcare Benefits [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Service cost	7,413	7,630	9,957
Interest cost	18,310	19,644	20,774
Expected return on plan assets	(9,423)	(9,386)	(9,781)
Prior service cost (credit)	(3,853)	(3,878)	(2,914)
Net loss	7,421	7,192	9,394
Net curtailment loss	0	0	11,643
Settlement loss	0	0	0
Net periodic benefit cost	$ 19,868	$ 21,202	$ 39,073