Supplementary Financial Information On Oil And Natural Gas Exploration Development and Production (Details 2)	12 Months Ended
Dec. 31, 2014 Mcf	Dec. 31, 2013 Mcf
Natural Gas [Member]
Proved Developed and Undeveloped Reserves [Abstract]
Beginning of year	723,190	679,410
Purchase (sale) of natural gas properties in place	(46,770)	(6,004)
Discoveries and extensions	0	66,680
Revisions	(30,843)	27,937
Production	(45,577)	(44,833)
Proved reserves, at end of year	600,000	723,190
Oil [Member]
Proved Developed and Undeveloped Reserves [Abstract]
Beginning of year	49,020	24,290
Purchase (sale) of natural gas properties in place	(26,290)	(2,430)
Discoveries and extensions	1,175	30,550
Revisions	3,700	2,420
Production	(6,905)	(5,810)
Proved reserves, at end of year	20,700	49,020
Consolidated Entities [Member] \| Natural Gas [Member]
Proved Developed and Undeveloped Reserves [Abstract]
Proved reserves, at end of year	10,350	24,510
Consolidated Entities [Member] \| Oil [Member]
Proved Developed and Undeveloped Reserves [Abstract]
Proved reserves, at end of year	300,000	361,595

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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)

-URI http://asc.fasb.org/extlink&oid=8451039&loc=d3e61831-109447

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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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 932

-SubTopic 235

-Section 50

-Paragraph 5

-URI http://asc.fasb.org/extlink&oid=8451039&loc=d3e61831-109447

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 932

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.4-10.(a)(2))

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Reference 3: http://www.xbrl.org/2003/role/presentationRef

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-Name Regulation S-X (SX)

-Number 210

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- Definition

Production of proved reserves.

+ 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 (e)

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- Definition

Purchase of minerals in place.

+ 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 (c)

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- Definition

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

-Name Accounting Standards Codification

-Topic 932

-SubTopic 235

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