Supplementary Information - Capitalized Costs Relating to Oil and Gas Producing Activities (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Proved Developed oil and gas properties	$ 395,129	$ 395,314
Proved Undeveloped oil and gas properties		1,274
Total Capitalized Costs	395,129	396,588
Accumulated depreciation, depletion and valuation allowance	204,213	188,988
Net Capitalized Costs	$ 190,916	$ 207,600

Amount of accumulated depreciation, depletion, amortization and valuation allowance relating to oil and gas producing activities.

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- Definition

The sum of capitalized costs relating to oil and gas producing activities before accounting for accumulated depreciation.

+ References

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- Definition

Net amount of capitalized costs relating to oil and gas producing activities.

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- Definition

Capitalized costs of proved properties incurred for any combination mineral interests acquisitions; wells and related equipment; support equipment and facilities; and uncompleted wells and equipment and other costs not previously disclosed within this table.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Properties
-URI http://asc.fasb.org/extlink&oid=21914647

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 932
-SubTopic 360
-Glossary Proved Properties
-URI http://asc.fasb.org/extlink&oid=6522428

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 932
-SubTopic 235
-Section 50
-Paragraph 13
-URI http://asc.fasb.org/extlink&oid=51678428&loc=d3e61901-109447

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- Definition

Capitalized costs of which include those incurred to (1) drill and equip wells that are not yet completed (2) acquire or construct equipment and facilities that are not yet installed.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 932
-SubTopic 235
-Section 50
-Paragraph 13
-URI http://asc.fasb.org/extlink&oid=51678428&loc=d3e61901-109447

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Uncompleted Wells, Equipment, and Facilities
-URI http://asc.fasb.org/extlink&oid=6527447

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No definition available.

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