Equity Investment in Savoy (Results of Operations for Oil and Gas Producing Activities) (Details)	12 Months Ended
Dec. 31, 2014 bbl	Dec. 31, 2013 bbl	Sep. 30, 2014
Oil [Member]
Results of Operations for Oil and Gas Producing Activities, by Geographic Area [Line Items]
Reserves, beginning balance	1,469,000	700,000
Extensions and discoveries	262,000	898,000
Production	(143,000)	(153,000)
Revisions to previous estimates	(840,000)	24,000
Change in ownership from 45% to 40%	(73,000)
Reserves, ending balance	675,000	1,469,000
Proved developed reserves	467,000	746,000
Proved undeveloped reserves (PUDs)	208,000	723,000
Natural Gas Liquids [Member]
Results of Operations for Oil and Gas Producing Activities, by Geographic Area [Line Items]
Reserves, beginning balance	99,000	29,000
Extensions and discoveries	14,000	58,000
Production	(9,000)	(11,000)
Revisions to previous estimates	(60,000)	23,000
Change in ownership from 45% to 40%	(5,000)
Reserves, ending balance	39,000	99,000
Proved developed reserves	30,000	60,000
Proved undeveloped reserves (PUDs)	9,000	39,000
Natural Gas [Member]
Results of Operations for Oil and Gas Producing Activities, by Geographic Area [Line Items]
Reserves, beginning balance	1,301,000	1,108,000
Extensions and discoveries	253,000	442,000
Production	(83,000)	(96,000)
Revisions to previous estimates	(956,000)	(153,000)
Change in ownership from 45% to 40%	(65,000)
Reserves, ending balance	450,000	1,301,000
Proved developed reserves	292,000	450,000
Proved undeveloped reserves (PUDs)	158,000	851,000
Savoy [Member]
Results of Operations for Oil and Gas Producing Activities, by Geographic Area [Line Items]
Equity method investment ownership percentage	40.00%		45.00%

Proved Developed And Undeveloped Reserves, Change In Ownership

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 323

-SubTopic 10

-Section 50

-Paragraph 3

-Subparagraph (a)(1)

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- Definition

Additions to proved reserves that result from (1) extension of the proved acreage of previously discovered (old) reservoirs through additional drilling in periods after discovery and (2) discovery of new fields with proved reserves or of new reservoirs of proved reserves in old fields.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 932

-SubTopic 235

-Section 50

-Paragraph 5

-Subparagraph (d)

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- Definition

The net quantity of proved reserves as of the balance sheet date. Proved oil reserves are the estimated quantities of crude oil and natural gas liquids which geological and engineering data demonstrate with reasonable certainty to be recoverable.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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- Definition

Production of proved reserves.

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-Publisher FASB

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-SubTopic 235

-Section 50

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Revisions represent changes in previous estimates of proved reserves, either upward or downward, resulting from new information (except for an increase in proved acreage) normally obtained from development drilling and production history or resulting from change in economic factors.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

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-SubTopic 235

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- Definition

Net quantities of an enterprise's interests in proved developed reserves of either crude oil (including condensate and natural gas liquids), natural gas, synthetic oil and gas, or other nonrenewable 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 4

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-Section 50

-Paragraph 9

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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.

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