Fair Value Measurements (Schedule Of Quantitative Information About Unobservable Inputs) (Details) - Level 3 [Member] $ in Thousands	9 Months Ended
	Sep. 30, 2015 USD ($) $ / Unit
Crude Oil [Member] | Collar [Member]
Derivative fair value | $	$ 2,300	[1]
Derivatives Valuation Technique(s)	Discounted cash flow
Unobservable Input	Forward commodity price curve
Crude Oil [Member] | Collar [Member] | Minimum [Member]
Forward commodity price curve	0.01
Crude Oil [Member] | Collar [Member] | Maximum [Member]
Forward commodity price curve	12.80
Natural Gas [Member] | Three-Way Collar [Member]
Derivative fair value | $	$ 182	[1]
Derivatives Valuation Technique(s)	Discounted cash flow
Unobservable Input	Forward commodity price curve
Natural Gas [Member] | Three-Way Collar [Member] | Minimum [Member]
Forward commodity price curve	0.01
Natural Gas [Member] | Three-Way Collar [Member] | Maximum [Member]
Forward commodity price curve	0.30

[1] The commodity contracts detailed in this category include a non-exchange-traded crude oil collar and a natural gas three-way collar that are valued based on NYMEX. The forward pricing range represents the low and high price expected to be paid or received within the settlement period.