Derivatives (Amount Of Gain Or (Loss) Recognized In Accumulated OCI On Derivative) (Details) (USD $) In Thousands	6 Months Ended
	Jun. 30, 2011		Jun. 30, 2010
Amount of Gain or (Loss) Recognized in Accumulated OCI on Derivative	$ (3,163)	[1]	$ 17,043	[1]
Interest Rate Swaps [Member]
Amount of Gain or (Loss) Recognized in Accumulated OCI on Derivative	0	[1]	(1,217)	[1]
Commodity Derivatives [Member]
Amount of Gain or (Loss) Recognized in Accumulated OCI on Derivative	$ (3,163)	[1]	$ 18,260	[1]

[1] Net of taxes.