Acres exchange in first trade.

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- Definition

Acres exchange in trade.

+ References

No definition available.

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- Definition

Cost related to sale of oil and gas properties.

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- Definition

Gain Loss On Sale Of Unproved Leases

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No definition available.

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Proceeds From Sale Of Unproved Leases

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No definition available.

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- Definition

Proceeds from sale of unproved property.

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No definition available.

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- Definition

This represents the reduction to PP&E balance during the period relating to acreage trades with third parties.

+ References

No definition available.

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- Definition

Area of land held.

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No definition available.

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- Definition

The carrying amount of a liability for an asset retirement obligation. An asset retirement obligation is a legal obligation associated with the disposal or retirement of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 410
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (c)
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-Publisher FASB
-Name Accounting Standards Codification
-Glossary Asset Retirement Obligation
-URI http://asc.fasb.org/extlink&oid=6505190

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- Definition

Amount classified as assets attributable to disposal group held for sale or disposed of, expected to be disposed of within one year or the normal operating cycle, if longer.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 20
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Amount of gain (loss) on sale or disposal of proven and unproven oil and gas properties.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Amount of gain (loss) on sale or disposal of property, plant and equipment assets, including oil and gas property and timber property.

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Amount of gain (loss) on sale or disposal of property without proven oil and gas reserves.

+ References

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- Definition

Amount of gain (loss) on sale or disposal of assets utilized in financial service operations.

+ References

No definition available.

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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.

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No definition available.

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- Definition

The cash inflow to dispose of long-lived, physical assets and mineral interests in oil and gas properties used for normal oil and gas operations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

The cash inflow from the sale of property, plant and equipment (capital expenditures), software, and other intangible assets.

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-Name Accounting Standards Codification
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Aggregate cash proceeds received from a combination of transactions in which noncurrent assets are sold, which may include the sale of a business, an investment in an affiliate (including an equity method investee), property, plant and equipment and intangible assets. Excludes sales of trading, available-for-sale, and held-to-maturity securities.

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No definition available.

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Amount of divestiture of long-lived, physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

+ References

No definition available.

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Sale of Oil and Natural Gas Property Interests - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2016 USD ($) a	Dec. 31, 2015 USD ($) a	Dec. 31, 2014 USD ($)
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Proceeds from the sale of central processing facility	$ 79,201,000	$ 40,139,000	$ 15,460,000
Sale of conventional oil and gas properties and related equipment	4,700,000
Gain on sale of assets	(6,936,000)	4,737,000	960,000
Assets held for sale	468,000	21,971,000
Gain or loss on sale of conventional oil and gas properties and related equipment	1,100,000
Proceeds from sale of unproved lease properties	3,900,000
Gain or Loss on sale of oil and natural gas properties	0
Proceeds from sale of unproved lease properties	4,800,000
Gain or Loss on sale of oil and natural gas properties	0
Acreage Trades [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gain or loss on sale of conventional oil and gas properties and related equipment	0	$ 0
Proceeds from sale of asset	$ 1,600,000
Area of land \| a	249.5	10,500
Acres exchange in first trade \| a		7,000
Credit related to reimbursement of capital expenditures		$ 17,500,000
Maximum [Member] \| Acreage Trades [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Acres exchange in trade \| a		1,500
Assets Held for Sale [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Cost related to sale of oil and gas properties		$ 21,800,000
Asset retirement obligations related to sale of oil and gas properties		19,100,000
Asset Sale [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gain on sale of assets	$ (7,600,000)
Proceeds from sale of asset	$ 63,800,000
Area of land \| a	9,900
Facility And Pipeline Sales [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Proceeds from the sale of central processing facility			16,800,000
Proceeds received from sale of central processing facility			15,500,000
Gain sale of central processing facility			$ 1,000,000
Sale of conventional oil and gas properties and related equipment		2,800,000
Gain on sale of assets		(100,000)
Central Processing Facility and Certain Pipelines [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Sale of conventional oil and gas properties and related equipment		36,000,000
Gain on sale of assets		4,800,000
Pipelines [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Sale of conventional oil and gas properties and related equipment	$ 400,000
Assets held for sale		$ 200,000
Pipelines [Member] \| Maximum [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gain on sale of assets	$ (100,000)