Represents the proceeds expected to be received on the sale of property before adjustment for closing costs.

No definition available.

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- Definition

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

+ References

No definition available.

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- Definition

Ratio of the net operating income produced by an asset and its capital cost (original prices paid to buy the asset), used as an input to measure fair value.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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-SubTopic 10
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-Subparagraph (bbb)
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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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- 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.

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- Definition

Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-SubTopic 10
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Properties and Equipment, Net - Narrative (Details) - USD ($) $ in Thousands	1 Months Ended			3 Months Ended	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Jun. 30, 2017	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 19, 2017	Dec. 11, 2017
Properties and Equipment
Impairment of oil and gas properties and other assets					$ 482,811	$ 435,619	$ 114,875
Properties and equipment, net (Successful efforts method)	$ 3,072,204	$ 4,250,125			$ 3,072,204	4,250,125
Oil and gas properties \| Significant Unobservable Inputs (Level 3)
Properties and Equipment
Capital rate					10.00%
West Virginia, Virginia, and Ohio \| Oil and gas properties, proved and unproved
Properties and Equipment
Impairment of oil and gas properties and other assets				$ 68,600
South Texas, East Texas and Louisiana
Properties and Equipment
Impairment of oil and gas properties and other assets		435,600
Sale of oil and gas properties before closing adjustments		$ 89,200				$ 89,200
South Texas, East Texas and Louisiana \| Oil and gas properties, proved and unproved
Properties and Equipment
Sale of oil and gas properties before closing adjustments			$ 89,900				$ 89,900
East And South Texas
Properties and Equipment
Impairment of oil and gas properties and other assets			$ 114,900
Assets Held-for-sale
Properties and Equipment
Consideration	762,195				$ 762,195
Assets Held-for-sale \| West Virginia, Virginia, and Ohio
Properties and Equipment
Impairment of oil and gas properties and other assets				68,600
Properties and equipment, net (Successful efforts method)				$ 37,900
Assets Held-for-sale \| Haynesville
Properties and Equipment
Consideration									$ 30,000
Assets Held-for-sale \| Eagle Ford
Properties and Equipment
Consideration								$ 765,000
Assets Held-for-sale \| Eagle Ford \| South Texas
Properties and Equipment
Impairment of oil and gas properties and other assets	414,300
Properties and equipment, net (Successful efforts method)	$ 765,600				$ 765,600