Derivatives And Risk Management (Schedule Of Derivative Instruments, Volumes Of Natural Gas Production) (Details) (Fixed Price Swaps [Member])	9 Months Ended
	Sep. 30, 2014 ft3
Year 2014 [Member]
Derivative [Line Items]
Volume of natural gas production	117,000,000,000
Year 2014 [Member] | Designated as Hedging Instrument [Member]
Derivative [Line Items]
Volume of natural gas production	71,000,000,000
Year 2014 [Member] | Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Volume of natural gas production	46,000,000,000
Year 2015 [Member]
Derivative [Line Items]
Volume of natural gas production	240,000,000,000
Year 2015 [Member] | Designated as Hedging Instrument [Member]
Derivative [Line Items]
Volume of natural gas production	120,000,000,000
Year 2015 [Member] | Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Volume of natural gas production	120,000,000,000