Supplementary Information on Oil And Gas Producing Activities (Unaudited) - Additional Information (Detail)	12 Months Ended
Dec. 31, 2014 Location MMcf	Dec. 31, 2013
Contingencies [Line Items]
Discount Rate to determine future cash flows	10.00%	10.00%
Estimate of Reserves	In 2013, the Company had net negative revisions of 8.2 MMcf, as 5 proved undeveloped locations were removed from its estimate of reserves at December 31, 2013
Revisions of previous estimates	8.2
Number of proved undeveloped locations removed from estimate of reserves	5
Gas [Member]
Contingencies [Line Items]
Price for oil and gas	3.31	3.67
Revisions of previous estimates	2,579,426	(13,028,885)
Oil [Member]
Contingencies [Line Items]
Price for oil and gas	94.99	96.78
Revisions of previous estimates	397	(1,808)
NGL [Member]
Contingencies [Line Items]
Price for oil and gas	41.74	35.36
Revisions of previous estimates	124,580	(722,757)

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Discount rate of after tax future net cash flows.

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- Definition

Number Of Proved Undeveloped Locations Removed From Estimate Of Reserves

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- Definition

The revenues derived from sales of oil or gas in each geographic area during the reporting period divided by the number of barrels of oil produced or thousands of cubic feet of gas produced.

+ References

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

-Publisher SEC

-Name Industry Guide

-Number 2

-Paragraph 3

-Subparagraph A

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- Definition

Description of the nature and impact of its cost-of-service ratemaking on oil and gas producing properties of rate regulated companies.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 932

-SubTopic 235

-Section S99

-Paragraph 1

-Subparagraph (SAB TOPIC 12.A.3.e)

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-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 12

-Section A

-Paragraph Question 3

-Subparagraph e

-Subsection 1

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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

-Name Accounting Standards Codification

-Topic 932

-SubTopic 235

-Section 50

-Paragraph 5

-Subparagraph (a)

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