Pension Plans and Other Postretirement Employee Benefits (Components Of Net Periodic Cost (Benefit)) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 1,337	$ 1,016	$ 2,619	$ 2,228
Interest cost	5,012	5,305	9,993	10,663
Expected return on plan assets	(7,205)	(8,106)	(14,378)	(15,902)
Amortization of prior service cost (credit)	192	171	385	342
Amortization of actuarial loss	3,975	2,445	7,678	4,958
Net periodic cost (benefit)	3,311	831	6,297	2,289
Other Postretirement Employee Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	19	111	142	223
Interest cost	488	815	1,239	1,743
Expected return on plan assets	0	0	0	0
Amortization of prior service cost (credit)	(2,496)	(2,134)	(4,775)	(4,268)
Amortization of actuarial loss	582	898	1,564	1,983
Net periodic cost (benefit)	$ (1,407)	$ (310)	$ (1,830)	$ (319)