Derivatives (Amount Of Gain Or (Loss) Recognized In Accumulated OCI On Derivative) (Details) (Commodity Derivatives [Member], USD $) In Thousands, unless otherwise specified	6 Months Ended
	Jun. 30, 2013		Jun. 30, 2012
Commodity Derivatives [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain Recognized in Accumulated OCI on Derivative (Effective Portion)	$ 1,709	[1]	$ 30,314	[1]

[1] Net of taxes.