Amount of gain (loss) on sale or disposal of proven and unproven oil and gas properties.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3602-108585

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- 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.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
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Period Type:	duration

- 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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3179-108585

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DIVESTITURES - Narrative (Details) - USD ($) $ in Thousands		4 Months Ended	8 Months Ended	12 Months Ended
DIVESTITURES - Narrative (Details) - USD ($) $ in Thousands	Aug. 06, 2018	Apr. 28, 2017	Dec. 31, 2017	Dec. 31, 2019	Dec. 31, 2018
Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gain on sale of properties, net of purchase price adjustments		$ 0	$ 0	$ 1,177	$ 27,324
Mid-Continent Region
Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Proceeds from divestiture of businesses	$ 103,500
Gain on sale of properties, net of purchase price adjustments	$ 28,600