Amount Spent For Developing Proved Undeveloped Reserves

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- Definition

Amount to be spent on developing proved undeveloped reserves

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Annual discount for estimated timing of cash flows.

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- Definition

The amount spent during the fiscal year to develop proved undeveloped reserves.

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- Definition

Conversion Of Undeveloped Proved Reserves To Developed Proved Reserves, Volume

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- Definition

Marcellus Shale Wells Developed

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Percent Marcellus Shale Wells Developed

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- Definition

Proved Undeveloped Reserves, Additions

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- Definition

Proved undeveloped reserves as a percentage of total proved reserves.

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- Definition

Proved Undeveloped Reserves, Conversions To Developed Reserves

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- Definition

Proved Undeveloped Reserves, Decrease

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- Definition

Proved Undeveloped Reserves, Downward Revisions

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- Definition

Proved Undeveloped Reserves, Increase

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- Definition

Proved Undeveloped Reserves, Percentage

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- Definition

Proved Undeveloped Reserves, Removed

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- Definition

Proved Undeveloped Reserves, Sales

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- Definition

Proved Undeveloped Reserves, Upward Revisions

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- Definition

Reimbursed Drilling Carry Costs for JDA Partner

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- Definition

Net quantities of an enterprise's interests in proved undeveloped reserves of either crude oil (including condensate and natural gas liquids), natural gas, synthetic oil and gas, or other renewable natural resource that is intended to be upgraded into synthetic oil and gas as of the beginning and the end of the year. "Net" quantities of reserves include those relating to the enterprise's operating and nonoperating interests in properties. Quantities of reserves relating to royalty interests owned are included in "net" quantities if the necessary information is available to the enterprise. "Net" quantities does not include reserves relating to interests of others in properties owned by the enterprise. The unit of measure for reserve quantities is defined as "barrels" for oil and synthetic oil reserves or "cubic feet" or "cubic meters" for natural gas and synthetic gas reserves.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 932
-SubTopic 235
-Section 50
-Paragraph 9
-URI http://asc.fasb.org/extlink&oid=68064819&loc=d3e61884-109447

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 932
-SubTopic 235
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=68064819&loc=d3e61797-109447

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Supplementary Information For Oil And Gas Producing Activities (Narrative) (Details) $ in Millions, ft³ in Billions	12 Months Ended
	Sep. 30, 2016 USD ($) ft³	Sep. 30, 2015 USD ($) MBbls ft³	Sep. 30, 2014 USD ($) ft³	Sep. 30, 2013	Sep. 30, 2012
Reserve Quantities [Line Items]
Amount spent for developing proved undeveloped reserves \| $	$ 92.8	$ 161.8	$ 179.9
Proved Undeveloped Reserve (Volume)	543	827	512
Percentage of PUD reserves to the total proved reserves	29.00%	35.00%	27.00%
Decrease in proved undeveloped (PUD) reserve	284
New PUD reserve additions	102	496
PUD Sales	166
PUD Upward Revisions		26
PUD Downward Revisions	14
PUD conversions to developed reserves	110	168
Proved Undeveloped Reserves, Removed	96	39
Increase in Proved undeveloped (PUD) reserve		315
Investment made to convert proved undeveloped reserves to developed reserves \| $	$ 93.0	$ 162.0
Reimbursed Drilling Carry Costs for JDA Partner \| $	$ 36.0
Conversion of undeveloped proved reserves to developed proved reserves	92	168
Conversion of PUD to Developed as a Percentage of PUD Reserves Booked at End of Prior Year	11.00%	33.00%	51.00%	39.00%	33.00%
Marcellus Shale Wells Developed	31
Percent Marcellus Shale Wells Developed	28.00%
Arbitrary discount rate	10.00%
West Coast Region [Member]
Reserve Quantities [Line Items]
Proved Undeveloped Reserves, Removed		2
Midway Sunset [Member]
Reserve Quantities [Line Items]
Proved Undeveloped Reserves, Removed \| MBbls		279
Marcellus Shale Fields [Member]
Reserve Quantities [Line Items]
Proved Undeveloped Reserve (Volume)	542	825	504
New PUD reserve additions	103	494
Proved Undeveloped Reserves, Removed	74	37
Geneseo Shale [Member]
Reserve Quantities [Line Items]
Proved Undeveloped Reserves, Removed	23
Total PUD Reserve Additions Estimated In The Next Fiscal Year [Member]
Reserve Quantities [Line Items]
Amount to be spent on developing proved undeveloped reserves \| $	$ 124.0
Conversion Of Undeveloped Proved Reserves To Developed Proved Reserves Including Revisions [Member]
Reserve Quantities [Line Items]
Conversion of undeveloped proved reserves to developed proved reserves	110	184
Impact of JDA Sales [Member]
Reserve Quantities [Line Items]
Conversion of undeveloped proved reserves to developed proved reserves	207
Conversion of PUD to Developed as a Percentage of PUD Reserves Booked at End of Prior Year	25.00%