Derivatives (Summary Of Derivative Instruments Contracts) (Details)	Mar. 31, 2015 MMBTU	Sep. 30, 2014 MMBTU
Natural Gas Costless Collars [Member] | Fixed Price One [Member]
Derivative [Line Items]
Production volume covered per month - Natural Gas	100,000	140,000
Natural Gas Costless Collars [Member] | Fixed Price Two [Member]
Derivative [Line Items]
Production volume covered per month - Natural Gas	100,000
Natural Gas Costless Collars [Member] | Fixed Price Three [Member]
Derivative [Line Items]
Production volume covered per month - Natural Gas	70,000
Natural Gas Costless Collars [Member] | Fixed Price Four [Member]
Derivative [Line Items]
Production volume covered per month - Natural Gas	70,000
Natural Gas Costless Collars [Member] | Fixed Price Five [Member]
Derivative [Line Items]
Production volume covered per month - Natural Gas	50,000
Natural Gas Costless Collars [Member] | Fixed Price Six [Member]
Derivative [Line Items]
Production volume covered per month - Natural Gas	70,000
Natural Gas Fixed Price Swaps [Member] | Fixed Price Two [Member]
Derivative [Line Items]
Production volume covered per month - Natural Gas		140,000
Contract price		4.11
Natural Gas Fixed Price Swaps [Member] | Fixed Price Three [Member]
Derivative [Line Items]
Production volume covered per month - Natural Gas		30,000
Contract price		4.30
Natural Gas Fixed Price Swaps [Member] | Fixed Price Four [Member]
Derivative [Line Items]
Production volume covered per month - Natural Gas		40,000
Contract price		4.61
Oil Costless Collars [Member] | Fixed Price Five [Member]
Derivative [Line Items]
Production volume covered per month - Oil		4,000
Oil Costless Collars [Member] | Fixed Price Six [Member]
Derivative [Line Items]
Production volume covered per month - Oil		5,000
Oil Costless Collars [Member] | Fixed Price Seven [Member]
Derivative [Line Items]
Production volume covered per month - Oil	10,000
Oil Fixed Price Swaps [Member] | Fixed Price Seven [Member]
Derivative [Line Items]
Production volume covered per month - Oil		3,000
Contract price		94.50
Oil Fixed Price Swaps [Member] | Fixed Price Eight [Member]
Derivative [Line Items]
Production volume covered per month - Oil	7,000	4,000
Contract price	96.80	99.40
Oil Fixed Price Swaps [Member] | Fixed Price Nine [Member]
Derivative [Line Items]
Production volume covered per month - Oil	5,000	4,000
Contract price	97.40	95.25
Oil Fixed Price Swaps [Member] | Fixed Price Ten [Member]
Derivative [Line Items]
Production volume covered per month - Oil	4,000	5,000
Contract price	97.25	94.20
Oil Fixed Price Swaps [Member] | Fixed Price Eleven [Member]
Derivative [Line Items]
Production volume covered per month - Oil	5,000	6,000
Contract price	94.56	92.85
Oil Fixed Price Swaps [Member] | Fixed Price Twelve [Member]
Derivative [Line Items]
Production volume covered per month - Oil	7,000	7,000
Contract price	93.91	96.80
Oil Fixed Price Swaps [Member] | Fixed Price Thirteen [Member]
Derivative [Line Items]
Production volume covered per month - Oil		5,000
Contract price		97.40
Oil Fixed Price Swaps [Member] | Fixed Price Fourteen [Member]
Derivative [Line Items]
Production volume covered per month - Oil		4,000
Contract price		97.25
Oil Fixed Price Swaps [Member] | Fixed Price Fifteen [Member]
Derivative [Line Items]
Production volume covered per month - Oil		5,000
Contract price		94.56
Oil Fixed Price Swaps [Member] | Fixed Price Sixteen [Member]
Derivative [Line Items]
Production volume covered per month - Oil		7,000
Contract price		93.91
Minimum [Member] | Natural Gas Costless Collars [Member] | Fixed Price One [Member]
Derivative [Line Items]
Contract price	3.75	3.75
Minimum [Member] | Natural Gas Costless Collars [Member] | Fixed Price Two [Member]
Derivative [Line Items]
Contract price	3.50
Minimum [Member] | Natural Gas Costless Collars [Member] | Fixed Price Three [Member]
Derivative [Line Items]
Contract price	3.25
Minimum [Member] | Natural Gas Costless Collars [Member] | Fixed Price Four [Member]
Derivative [Line Items]
Contract price	3.50
Minimum [Member] | Natural Gas Costless Collars [Member] | Fixed Price Five [Member]
Derivative [Line Items]
Contract price	3.50
Minimum [Member] | Natural Gas Costless Collars [Member] | Fixed Price Six [Member]
Derivative [Line Items]
Contract price	3.50
Minimum [Member] | Oil Costless Collars [Member] | Fixed Price Five [Member]
Derivative [Line Items]
Contract price		85.00
Minimum [Member] | Oil Costless Collars [Member] | Fixed Price Six [Member]
Derivative [Line Items]
Contract price		90.00
Minimum [Member] | Oil Costless Collars [Member] | Fixed Price Seven [Member]
Derivative [Line Items]
Contract price	80.00
Maximum [Member] | Natural Gas Costless Collars [Member] | Fixed Price One [Member]
Derivative [Line Items]
Contract price	4.25	4.50
Maximum [Member] | Natural Gas Costless Collars [Member] | Fixed Price Two [Member]
Derivative [Line Items]
Contract price	4.10
Maximum [Member] | Natural Gas Costless Collars [Member] | Fixed Price Three [Member]
Derivative [Line Items]
Contract price	4.00
Maximum [Member] | Natural Gas Costless Collars [Member] | Fixed Price Four [Member]
Derivative [Line Items]
Contract price	4.05
Maximum [Member] | Natural Gas Costless Collars [Member] | Fixed Price Five [Member]
Derivative [Line Items]
Contract price	4.00
Maximum [Member] | Natural Gas Costless Collars [Member] | Fixed Price Six [Member]
Derivative [Line Items]
Contract price	3.95
Maximum [Member] | Oil Costless Collars [Member] | Fixed Price Five [Member]
Derivative [Line Items]
Contract price		100.00
Maximum [Member] | Oil Costless Collars [Member] | Fixed Price Six [Member]
Derivative [Line Items]
Contract price		97.00
Maximum [Member] | Oil Costless Collars [Member] | Fixed Price Seven [Member]
Derivative [Line Items]
Contract price	86.50