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Represents the preferential rights to purchase that were exercised by other working interest owners.

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Amount classified as assets attributable to disposal group held for sale or disposed of.

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Amount of consideration received or receivable for the disposal of assets and liabilities, including discontinued operation.

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No definition available.

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

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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.

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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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Amount classified as liabilities attributable to disposal group held for sale or disposed of.

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The net cash paid (received) associated with the acquisition or disposal of all investments, including securities and other assets.

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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.

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DIVESTITURES (Details) - USD ($) $ in Thousands, shares in Millions	1 Months Ended			3 Months Ended			4 Months Ended	9 Months Ended
	Sep. 30, 2019	Apr. 30, 2019	Jan. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Sep. 30, 2018	Sep. 30, 2018	Sep. 30, 2019	Dec. 31, 2019	Oct. 31, 2019	Jul. 31, 2019
Significant Acquisitions And Disposals [Line Items]
Proceeds from sale of oil and natural gas properties							$ 136,483	$ 111,575
Gain on sale of certain oil and gas properties				$ 661		$ 28	47	679
Impairment of oil and gas properties				16,325		$ 2,565	$ 2,565	115,604
Assets held for sale	$ 9,284			9,284				9,284
Liabilities related to assets held for sale	2,759			2,759				2,759
Magnolia Oil Gas Parent LLC And Magnolia Oil Gas Corporation [Member]
Significant Acquisitions And Disposals [Line Items]
Business acquisition equity interests issued or issuable number of shares originally acquired then sold			4.2
Proceeds from sale of available-for-sale securities, equity			$ 51,700
Mid Continent Area Oil and Gas Properties [Member] \| Third Party Acquirer [Member]
Significant Acquisitions And Disposals [Line Items]
Proceeds from sale of oil and natural gas properties	5,300		$ 1,800		$ 2,300
Gain on sale of certain oil and gas properties								600
Preferential rights to purchase that were exercised by other working interest owners					$ 900
Impairment of oil and gas properties								1,700
San Jun Property [Member] \| Third Party Acquirer [Member]
Significant Acquisitions And Disposals [Line Items]
Proceeds from sale of oil and natural gas properties		$ 36,900
Impairment of oil and gas properties								25,300
Barnett Shale Property [Member]
Significant Acquisitions And Disposals [Line Items]
Impairment of oil and gas properties								75,300
Assets held for sale	6,700			6,700				6,700
Liabilities related to assets held for sale	300			300				300
Barnett Shale Property [Member] \| Third Party Acquirer [Member]
Significant Acquisitions And Disposals [Line Items]
Total purchase consideration											$ 72,000
Proceeds from sale of oil and natural gas properties	62,400
Barnett Shale Property [Member] \| Scenario \| Third Party Acquirer [Member]
Significant Acquisitions And Disposals [Line Items]
Total purchase consideration									$ 6,400
Monroe Field Property
Significant Acquisitions And Disposals [Line Items]
Total purchase consideration	200			200				200
Impairment of oil and gas properties								1,600
Assets held for sale	2,600			2,600				2,600
Liabilities related to assets held for sale	$ 2,400			$ 2,400				2,400
Permian Basin Property [Member]
Significant Acquisitions And Disposals [Line Items]
Impairment of oil and gas properties								$ 8,100
Permian Basin Property [Member] \| Subsequent Event
Significant Acquisitions And Disposals [Line Items]
Total purchase consideration										$ 3,000