Derivatives (Effect Of Derivative Instruments Recognized In Statement Of Operations, Not Designated As Hedging Instruments) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2014		Dec. 31, 2013
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain or (loss) recognized in income on derivative	$ 30,147		$ (8,184)
Loss on derivatives not designated as hedging instruments, amount settled during period	(6,038)		(1,764)
Commodity Contract
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain or (loss) recognized in income on derivative	$ 30,147	[1]	$ (8,184)	[1]

[1] Amount settled during the period is a loss of $6,038 and $1,764, respectively.