Derivatives (Summary Of Derivative Instruments Contracts) (Details)	Dec. 31, 2013 MMBTU	Sep. 30, 2013 MMBTU
Natural Gas Costless Collars [Member] | Fixed Price One [Member]
Derivative [Line Items]
Production volume covered per month - Natural Gas	160,000	80,000
Natural Gas Costless Collars [Member] | Fixed Price Two [Member]
Derivative [Line Items]
Production volume covered per month - Natural Gas	40,000	50,000
Natural Gas Costless Collars [Member] | Fixed Price Three [Member]
Derivative [Line Items]
Production volume covered per month - Natural Gas	50,000	100,000
Natural Gas Costless Collars [Member] | Fixed Price Four [Member]
Derivative [Line Items]
Production volume covered per month - Natural Gas	80,000	160,000
Natural Gas Costless Collars [Member] | Fixed Price Five [Member]
Derivative [Line Items]
Production volume covered per month - Natural Gas	140,000
Natural Gas Fixed Price Swaps [Member] | Fixed Price Five [Member]
Derivative [Line Items]
Production volume covered per month - Natural Gas		100,000
Contract price		3.505
Natural Gas Fixed Price Swaps [Member] | Fixed Price Six [Member]
Derivative [Line Items]
Production volume covered per month - Natural Gas	80,000	70,000
Contract price	4.085	3.400
Natural Gas Fixed Price Swaps [Member] | Fixed Price Seven [Member]
Derivative [Line Items]
Production volume covered per month - Natural Gas	140,000	40,000
Contract price	4.110	3.655
Natural Gas Fixed Price Swaps [Member] | Fixed Price Eight [Member]
Derivative [Line Items]
Production volume covered per month - Natural Gas	50,000	100,000
Contract price	4.200	4.320
Natural Gas Fixed Price Swaps [Member] | Fixed Price Nine [Member]
Derivative [Line Items]
Production volume covered per month - Natural Gas	50,000
Contract price	4.180
Natural Gas Fixed Price Swaps [Member] | Fixed Price Ten [Member]
Derivative [Line Items]
Production volume covered per month - Natural Gas	50,000
Contract price	4.210
Oil costless collars [Member] | Fixed Price Nine [Member]
Derivative [Line Items]
Production volume covered per month - Oil		3,000
Oil costless collars [Member] | Fixed Price Ten [Member]
Derivative [Line Items]
Production volume covered per month - Oil		4,000
Oil costless collars [Member] | Fixed Price Eleven [Member]
Derivative [Line Items]
Production volume covered per month - Oil	4,000	2,000
Oil costless collars [Member] | Fixed Price Twelve [Member]
Derivative [Line Items]
Production volume covered per month - Oil	4,000	4,000
Oil costless collars [Member] | Fixed Price Thirteen [Member]
Derivative [Line Items]
Production volume covered per month - Oil	3,667
Oil Fixed Price Swaps [Member] | Fixed Price Thirteen [Member]
Derivative [Line Items]
Production volume covered per month - Oil		4,000
Contract price		105.25
Oil Fixed Price Swaps [Member] | Fixed Price Fourteen [Member]
Derivative [Line Items]
Production volume covered per month - Oil	3,000
Contract price	94.50
Minimum [Member] | Natural Gas Costless Collars [Member] | Fixed Price One [Member]
Derivative [Line Items]
Contract price	4.00	3.75
Minimum [Member] | Natural Gas Costless Collars [Member] | Fixed Price Two [Member]
Derivative [Line Items]
Contract price	3.25	3.75
Minimum [Member] | Natural Gas Costless Collars [Member] | Fixed Price Three [Member]
Derivative [Line Items]
Contract price	3.50	3.75
Minimum [Member] | Natural Gas Costless Collars [Member] | Fixed Price Four [Member]
Derivative [Line Items]
Contract price	3.75	4.00
Minimum [Member] | Natural Gas Costless Collars [Member] | Fixed Price Five [Member]
Derivative [Line Items]
Contract price	3.75
Minimum [Member] | Oil costless collars [Member] | Fixed Price Nine [Member]
Derivative [Line Items]
Contract price		90.00
Minimum [Member] | Oil costless collars [Member] | Fixed Price Ten [Member]
Derivative [Line Items]
Contract price		90.00
Minimum [Member] | Oil costless collars [Member] | Fixed Price Eleven [Member]
Derivative [Line Items]
Contract price	90.00	90.00
Minimum [Member] | Oil costless collars [Member] | Fixed Price Twelve [Member]
Derivative [Line Items]
Contract price	85.00	90.00
Minimum [Member] | Oil costless collars [Member] | Fixed Price Thirteen [Member]
Derivative [Line Items]
Contract price	85.00
Maximum [Member] | Natural Gas Costless Collars [Member] | Fixed Price One [Member]
Derivative [Line Items]
Contract price	4.55	4.25
Maximum [Member] | Natural Gas Costless Collars [Member] | Fixed Price Two [Member]
Derivative [Line Items]
Contract price	3.90	4.30
Maximum [Member] | Natural Gas Costless Collars [Member] | Fixed Price Three [Member]
Derivative [Line Items]
Contract price	4.30	4.05
Maximum [Member] | Natural Gas Costless Collars [Member] | Fixed Price Four [Member]
Derivative [Line Items]
Contract price	4.35	4.55
Maximum [Member] | Natural Gas Costless Collars [Member] | Fixed Price Five [Member]
Derivative [Line Items]
Contract price	4.50
Maximum [Member] | Oil costless collars [Member] | Fixed Price Nine [Member]
Derivative [Line Items]
Contract price		102.00
Maximum [Member] | Oil costless collars [Member] | Fixed Price Ten [Member]
Derivative [Line Items]
Contract price		101.50
Maximum [Member] | Oil costless collars [Member] | Fixed Price Eleven [Member]
Derivative [Line Items]
Contract price	101.50	97.50
Maximum [Member] | Oil costless collars [Member] | Fixed Price Twelve [Member]
Derivative [Line Items]
Contract price	100.00	101.50
Maximum [Member] | Oil costless collars [Member] | Fixed Price Thirteen [Member]
Derivative [Line Items]
Contract price	99.00