Environmental Exit Costs, Gallons of Wastewater Transported

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- Definition

Litigation Settlement, Number Of Acres Received

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Loss Contingency, Number of Acres with Cloud on the Title

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- Definition

Oil And Gas Delivery Commitments And Contracts, Remaining Contractual Amount (BOE)

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- Definition

Amount of litigation expense, including but not limited to legal, forensic, accounting, and investigative fees.

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- Definition

Reflects the estimated amount of loss from the specified contingency as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=82911808&loc=d3e14435-108349

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 9
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=82911808&loc=d3e14557-108349

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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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COMMITMENTS AND CONTINGENCIES - Additional Information (Details)			12 Months Ended
	Oct. 24, 2017 USD ($) a	Nov. 04, 2015 a	Dec. 31, 2008 gal	Dec. 31, 2017 USD ($) MMBoe	Apr. 15, 2016 USD ($)	Aug. 31, 2014 USD ($)
Site Contingency [Line Items]
Gallons of wastewater transported \| gal			3,000
Number of acres with cloud on the title \| a		10,000
Net mineral acres received in lawsuit settlement \| a	917.2
Noncash lawsuit settlement	$ 6,400,000
Unfavorable Regulatory Action
Site Contingency [Line Items]
Order for payment of additional royalties					$ 189,000
Crude Oil and Natural Gas
Site Contingency [Line Items]
Oil and gas delivery commitments, volume \| MMBoe				2.9
Minimum \| Unfavorable Regulatory Action
Site Contingency [Line Items]
Order for payment of additional royalties						$ 129,700
Maximum \| Unfavorable Regulatory Action
Site Contingency [Line Items]
Order for payment of additional royalties				$ 24,000,000