Pension Plans And Other Postretirement Employee Benefits (Components Of Net Periodic Cost (Benefit)) (Details) (USD $) In Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Pension Plans [Member]
Service cost	$ 1,016	$ 1,104	$ 2,228	$ 2,316
Interest cost	5,305	5,405	10,663	10,825
Expected return on plan assets	(8,106)	(8,268)	(15,902)	(16,567)
Amortization of prior service cost (credit)	171	200	342	406
Amortization of actuarial loss	2,445	2,029	4,958	4,087
Curtailment loss (gain)				64
Net periodic cost (benefit)	831	470	2,289	1,131
Other Postretirement Employee Benefits [Member]
Service cost	111	75	223	208
Interest cost	815	911	1,743	1,986
Expected return on plan assets
Amortization of prior service cost (credit)	(2,134)	(2,135)	(4,268)	(4,286)
Amortization of actuarial loss	898	829	1,983	2,316
Curtailment loss (gain)				(320)
Net periodic cost (benefit)	$ (310)	$ (320)	$ (319)	$ (96)