Derivatives (Gain Or Loss Of Reclassified Accumulated Other Comprehensive Income And Recognized In Income) (Details) (Commodity Derivatives [Member], USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2014		Mar. 31, 2013
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain Reclassified from Accumulated OCI into Income	$ 0		$ 3,831
Amount of Gain or (Loss) Recognized in Income	0		(1,349)
Oil And Natural Gas Revenue [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain Reclassified from Accumulated OCI into Income	0	[1]	3,831	[1]
Amount of Gain or (Loss) Recognized in Income	0		0
Loss on derivatives not designated as hedges and hedge ineffectiveness [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain Reclassified from Accumulated OCI into Income	0		0
Amount of Gain or (Loss) Recognized in Income	$ 0	[2]	$ (1,349)	[2]

[1] Effective portion of gain (loss).

[2] Ineffective portion of gain (loss).