Business acquisition and divestiture.

No definition available.

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- Definition

The cash outflow to purchase remaining minority interest.

+ References

No definition available.

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- Definition

Percentage of interest on proved oil development property.

+ References

No definition available.

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- Definition

This element represents the amount of earnings or loss of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(1)
-URI http://asc.fasb.org/extlink&oid=65885119&loc=d3e1392-128463

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- Definition

This element represents the amount of revenue of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.

+ References

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- Definition

Amount before tax of gain (loss) recognized on the sale or disposal of a disposal group. Excludes discontinued operations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=68055307&loc=d3e2443-110228

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=64862545&loc=d3e2941-110230

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- Definition

The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Investing Activities
-URI http://asc.fasb.org/extlink&oid=6516133

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3213-108585

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- Definition

The cash outflow to purchase long lived physical asset for use in the normal oil and gas operations and to purchase mineral interests in oil and gas properties not intended for resale.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Investing Activities
-URI http://asc.fasb.org/extlink&oid=6516133

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3213-108585

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- Definition

The cash inflow associated with the amount received from the sale of a portion of the company's business, for example a segment, division, branch or other business, during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3179-108585

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-Publisher FASB
-Name Accounting Standards Codification
-Glossary Investing Activities
-URI http://asc.fasb.org/extlink&oid=6516133

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Acquisitions and Divestitures - Additional Information (Detail) - USD ($)						12 Months Ended
	Jul. 14, 2016	Jun. 14, 2016	Nov. 03, 2015	Jul. 01, 2014	Mar. 25, 2014	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Business Acquisition And Divestiture [Line Items]
Acquisitions of oil and natural gas properties						$ 0	$ 100,730,000	$ 1,083,761,000
Permian Basin
Business Acquisition And Divestiture [Line Items]
Proceeds from divestitures							900,000
Permian Basin \| Texas And New Mexico
Business Acquisition And Divestiture [Line Items]
Proceeds from divestitures							600,000
Rockies Divestiture [Member]
Business Acquisition And Divestiture [Line Items]
Disposal group, not discontinued operation, (gain) loss on properties						4,200,000
Permian Divestiture [Member]
Business Acquisition And Divestiture [Line Items]
Disposal group, not discontinued operation, (gain) loss on properties						(6,100,000)
Immaterial Divestitures [Member]
Business Acquisition And Divestiture [Line Items]
Disposal group, not discontinued operation, (gain) loss on properties						(900,000)
Immaterial Divestitures [Member] \| Maximum [Member]
Business Acquisition And Divestiture [Line Items]
Proceeds from divestitures						100,000
Disposal Group Not Discontinued Operation [Member] \| Rockies Divestiture [Member]
Business Acquisition And Divestiture [Line Items]
Proceeds from divestitures	$ 16,400,000
Disposal Group Not Discontinued Operation [Member] \| Permian Divestiture [Member]
Business Acquisition And Divestiture [Line Items]
Proceeds from divestitures		$ 36,700,000
Disposal Group Not Discontinued Operation [Member] \| Permian Divestiture [Member] \| Accounts Receivable [Member]
Business Acquisition And Divestiture [Line Items]
Proceeds from divestitures						300,000
Disposal Group Not Discontinued Operation [Member] \| Permian Divestiture [Member] \| Cash [Member]
Business Acquisition And Divestiture [Line Items]
Proceeds from divestitures						$ 36,400,000
2015 Beta Acquisition [Member]
Business Acquisition And Divestiture [Line Items]
Purchase of noncontrolling interest in SPBPC			$ 6,000,000
Acquisitions of oil and natural gas properties			$ 94,600,000
Revenue recorded in statement of operations							3,600,000
Earnings (Losses) recorded in statement of operations							$ (1,000,000)
Wyoming Acquisition [Member]
Business Acquisition And Divestiture [Line Items]
Revenue recorded in statement of operations				$ 72,800,000
Earnings (Losses) recorded in statement of operations				22,900,000
Purchase price				$ 906,100,000
Eagle Ford [Member]
Business Acquisition And Divestiture [Line Items]
Revenue recorded in statement of operations								36,600,000
Earnings (Losses) recorded in statement of operations								$ 16,300,000
Purchase price					$ 168,100,000
Eagle Ford [Member] \| Leasehold [Member]
Business Acquisition And Divestiture [Line Items]
Percentage of leasehold interest acquired					30.00%