Pension And Other Postretirement Benefit Plans (Components Of Net Periodic Cost) (Details) (USD $) In Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 2,951	$ 2,853	$ 8,852	$ 8,559
Interest cost	9,555	9,024	28,666	27,072
Expected return on plan assets	(12,585)	(10,856)	(37,757)	(32,570)
Amortization of prior service cost	105	135	314	405
Amortization of net loss (gain)	1,685	1,743	5,054	5,228
Net periodic cost	1,711	2,899	5,129	8,694
Other Postretirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	28	29	85	89
Interest cost	156	190	441	564
Expected return on plan assets
Amortization of prior service cost	(127)		(177)
Amortization of net loss (gain)	43	(40)	(75)	(120)
Net periodic cost	$ 100	$ 179	$ 274	$ 533