Annual discount rate for discounting future cash flows.

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- Definition

The calculated weighted average natural gas price per mcf utilized for purposes of estimating the company's proved reserves and future net revenue.

+ References

No definition available.

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- Definition

The calculated weighted average natural gas liquids price per barrel utilized for purposes of estimating the company's proved reserves and future net revenue.

+ References

No definition available.

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- Definition

The calculated weighted average oil price per barrel utilized for purposes of estimating the company's proved reserves and future net revenue.

+ References

No definition available.

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- Definition

Increase In Impairment Of Oil And Gas Properties

+ References

No definition available.

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- Definition

Interest costs capitalized on unevaluated properties.

+ References

No definition available.

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- Definition

The description of the weighted average prices used in calculating the company's proved reserves and future net revenues.

+ References

No definition available.

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- Definition

The period of time in which unproved oil and gas properties/projects are expected to be evaluated and included in the amortization base for oil and gas properties.

+ References

No definition available.

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- Definition

The number of unproved oil and gas properties/projects associated with capitalized costs excluded from amortization.

+ References

No definition available.

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- Definition

The expense recorded to reduce the value of oil and gas assets consisting of proved properties and unproved properties as the estimate of future successful production from these properties is reduced.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6391110&loc=d3e2921-110230

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 932
-SubTopic 360
-Section 35
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=28370743&loc=d3e66150-109466

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585

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

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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
-Section 50
-Paragraph 5
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=8451039&loc=d3e61831-109447

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- Definition

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

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- Definition

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.

+ References

No definition available.

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Supplemental Information on Oil and Natural Gas Operations - Unaudited - Additional Information (Detail) MBbls in Thousands, $ in Thousands							3 Months Ended								12 Months Ended
	Dec. 31, 2015 USD ($) Project $ / bbl $ / Bngl $ / Mcf	Sep. 30, 2015 USD ($) $ / bbl $ / Bngl $ / Mcf	Jun. 30, 2015 USD ($) $ / bbl $ / Bngl $ / Mcf	Mar. 31, 2015 USD ($) $ / bbl $ / Bngl $ / Mcf	Dec. 31, 2014 USD ($) $ / bbl $ / Mcf	Sep. 30, 2014 USD ($) $ / bbl $ / Mcf	Dec. 31, 2015 USD ($) Project $ / bbl $ / Bngl $ / Mcf	Sep. 30, 2015 USD ($) $ / bbl $ / Bngl $ / Mcf	Jun. 30, 2015 USD ($) $ / bbl $ / Bngl $ / Mcf	Mar. 31, 2015 USD ($) $ / bbl $ / Bngl $ / Mcf	Dec. 31, 2014 USD ($) $ / bbl $ / Mcf	Sep. 30, 2014 USD ($) $ / bbl $ / Mcf	Jun. 30, 2014 USD ($)	Mar. 31, 2014 USD ($)	Dec. 31, 2015 USD ($) Project $ / bbl $ / Bngl $ / Mcf MBbls MMcf	Dec. 31, 2014 USD ($) $ / bbl $ / Mcf MBbls MMcf	Dec. 31, 2013 USD ($) $ / bbl $ / Mcf MBbls MMcf
Reserve Quantities [Line Items]
Average 12-month oil prices net of differentials \| $ / bbl	51.16	57.76	68.68	78.99	89.46	94.94	51.16	57.76	68.68	78.99	89.46	94.94			51.16	89.46	102.21
Increase in written down value of oil and gas properties \| $					$ 13,342	$ 29,001
Average 12-month gas prices net of differentials \| $ / Mcf	2.19	2.44	2.47	2.96	3.68	4.19	2.19	2.44	2.47	2.96	3.68	4.19			2.19	3.68	3.66
Write-down of oil and gas properties before income tax effect \| $							$ 351,062	$ 295,679	$ 224,294	$ 491,412	$ 304,062	$ 47,130	$ 0	$ 0	$ 1,362,447	$ 351,192	$ 0
Interest costs capitalized on unevaluated properties \| $															$ 41,339	$ 45,722	$ 46,860
Specifically identified drilling projects \| Project	95						95								95
Projects expected to be evaluated															4 years
Adoption of assumption due to revision of oil and gas reporting requirements															Using a historical 12-month average pricing assumption
Annual discount rate for discounting future cash flows															10.00%
Oil And Gas [Member]
Reserve Quantities [Line Items]
Write-down of oil and gas properties before income tax effect \| $	$ 348,601	$ 295,679	$ 179,125	$ 491,412	$ 304,062	$ 47,130
Natural Gas Liquids (MBbls) [Member]
Reserve Quantities [Line Items]
Increase in written down value of oil and gas properties \| $							$ 24,797	$ 42,652	$ 47,784	$ 28,687
Average 12-month gas prices net of differentials	16.40	23.04	29.13	28.82	36.79	41.33	16.40	23.04	29.13	28.82	36.79	41.33			16.40	36.79
Extensions, discoveries and other additions \| MBbls															11	7,521	4,395
Sale of reserves primarily related to sale \| MBbls															0	556	0
Revisions of previous estimates \| MBbls															(20,777)	(331)	2,439
Average 12-month natural gas liquids prices net of differentials \| $ / bbl	16.40				36.79		16.40				36.79				16.40	36.79	37.59
Scenario, Adjustment [Member]
Reserve Quantities [Line Items]
Revisions of previous estimates															(570)		18
Well Performance [Member] \| Scenario, Adjustment [Member]
Reserve Quantities [Line Items]
Revisions of previous estimates															42		55
Appalachia Drilling Program [Member]
Reserve Quantities [Line Items]
Extensions, discoveries and other additions																118	117
Sale of reserves primarily related to sale																15
Deep Water Drilling Program [Member]
Reserve Quantities [Line Items]
Extensions, discoveries and other additions																116
GOM Conventional Shelf Properties [Member]
Reserve Quantities [Line Items]
Sale of reserves primarily related to sale																63