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.

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-Publisher FASB
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-SubTopic 20
-Section 50
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- Definition

Amount of assets held-for-sale that are not part of a disposal group, expected to be sold within a year or the normal operating cycle, if longer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 15
-Paragraph 4
-Subparagraph (b)(2)
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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
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- Definition

Amount of noncash consideration received for selling an asset or business through a noncash (or part noncash) transaction.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
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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.

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-Publisher FASB
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-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
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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.

+ References

No definition available.

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DIVESTITURES (Details) - USD ($) $ in Thousands		8 Months Ended	12 Months Ended
DIVESTITURES (Details) - USD ($) $ in Thousands	Aug. 06, 2018	Dec. 31, 2017	Dec. 31, 2018	Dec. 31, 2016
Property, Plant and Equipment [Line Items]
Asset retirement obligations for oil and gas properties		$ 38,262	$ 29,405
Gain on sale of properties		0	$ 27,324	$ 0
North Park Basin Region
Property, Plant and Equipment [Line Items]
Assets, held-for-sale		5,400
Mid-Continent Region
Property, Plant and Equipment [Line Items]
Proceeds from divestiture of businesses	$ 102,900
Gain on sale of properties	27,300
Purchase price	$ 117,000
Held-for-sale \| North Park Basin Region
Property, Plant and Equipment [Line Items]
Asset retirement obligations for oil and gas properties		$ 5,400