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- Definition

Business Combination, Wells Drilled, Uncompleted

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Disposal Group, Including Discontinued Operations, Asset Retirement Obligations Assumed

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- Definition

Proceeds from Asset Exchange Agreement

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- Definition

Area of land held.

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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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- Definition

Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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- Definition

Fair value at acquisition-date of the equity interest in the acquiree held by the acquirer, immediately before the acquisition date for businesses combined in stages.

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- Definition

In a business combination achieved in stages, this element represents the amount of gain recognized by the entity as a result of remeasuring to fair value the equity interest in the acquiree it held before the business combination.

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- Definition

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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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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Amount of gain (loss) on sale or disposal of assets, including but not limited to property plant and equipment, intangible assets and equity in securities of subsidiaries or equity method investee.

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- Definition

Fractional interest owned based on working interests or other economic arrangements of lease area on which wells have not been drilled or completed to a point that would permit the production of commercial quantities of oil and gas regardless of whether or not such area contains proved reserves.

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The amount of impairment loss recognized in the period resulting from the write-down of the carrying amount of a finite-lived intangible asset to fair value.

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The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

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The cash inflow from the sale of property, plant and equipment (capital expenditures), software, and other intangible assets.

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The total number of producing gas wells and gas wells capable of production, in which the entity owns an undivided working interest.

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Acquisitions and Dispositions Narrative (Details) $ in Thousands						1 Months Ended				3 Months Ended		9 Months Ended
	Aug. 31, 2018 USD ($) a	May 02, 2018 USD ($) well	Mar. 30, 2018 USD ($)	Jan. 03, 2018 USD ($)	Dec. 14, 2017 USD ($)	May 31, 2018 USD ($)	Jun. 30, 2017 USD ($) a well producing_wells	May 31, 2017 USD ($) a	Apr. 30, 2017 USD ($)	Sep. 30, 2018 USD ($)	Sep. 30, 2017 USD ($) a	Sep. 30, 2018 USD ($)	Sep. 30, 2017 USD ($) a
Business Acquisition [Line Items]
Net gain (loss) on sale										$ 134,320	$ 45,743	$ 148,942	$ 184,319
Cash proceeds from Asset Exchange Agreement		$ 7,000
Impairment of other intangible										0	0	18,650	0
Gain on remeasurement of fair value of previously held equity interest										$ 0	0	623,663	0
Proceeds from sale of assets												$ 500,811	$ 408,957
Producing gas wells \| producing_wells							12
Drilled but uncompleted wells \| well							15
Midstream Acquisition [Member]
Business Acquisition [Line Items]
Cash consideration transferred				$ 305,000	$ 305,000
Fair value of previously held equity interest				799,033
Gain on remeasurement of fair value of previously held equity interest				$ 623,663
Ohio Utica Joint Venture Assets [Member]
Business Acquisition [Line Items]
Net undeveloped acres \| a	26,000
Net gain (loss) on sale	$ 130,849
Proceeds from sale of assets	$ 381,214
Asset Exchange Agreement with HG Energy [Member]
Business Acquisition [Line Items]
Net gain (loss) on sale		$ 286
Number of wells added to existing commitment \| well		40
Shallow Oil, Gas, and CBM Assets in Pennsylvania and West Virginia [Member]
Business Acquisition [Line Items]
Net gain (loss) on sale			$ 4,432
Cash consideration received in sale of oil and gas assets			89,296
Asset retirement obligations assumed			$ 196,514
Surface Land, Colorado [Member]
Business Acquisition [Line Items]
Net gain (loss) on sale											$ 18,758
Net acres of land \| a											22,000		22,000
Proceeds from sale of assets											$ 23,703
Marcellus Shale Acres, Allegheny and Westmoreland County [Member]
Business Acquisition [Line Items]
Net gain (loss) on sale											$ 15,251
Net acres of land \| a											7,500		7,500
Proceeds from sale of assets											$ 36,649
Marcellus And Utica Shale, Allegheny, Washington And Westmoreland Counties [Member]
Business Acquisition [Line Items]
Net gain (loss) on sale							$ 58,541
Net acres of land \| a							11,100
Proceeds from sale of assets							$ 83,500
Marcellus And Utica Acres, Doddridge And Wetzel Counties [Member]
Business Acquisition [Line Items]
Net gain (loss) on sale							$ (8,591)
Net acres of land \| a							11,000
Proceeds from sale of assets							$ 129,651
Utica Point Pleasant Shale Acres, Jefferson, Belmont And Guernsey Counties [Member]
Business Acquisition [Line Items]
Net gain (loss) on sale								$ 72,346
Net acres of land \| a								6,300
Proceeds from sale of assets								$ 76,585
Knox and Coalfield [Member]
Business Acquisition [Line Items]
Net gain (loss) on sale									$ 606
Proceeds from sale of assets									$ 18,944
CNX Gathering LLC [Member]
Business Acquisition [Line Items]
Ownership percentage in equity method investment					50.00%					50.00%		50.00%
Customer Relationships [Member] \| Midstream [Member]
Business Acquisition [Line Items]
Impairment of other intangible						$ 18,650						$ 18,650
CONE Midstream GP LLC [Member]
Business Acquisition [Line Items]
Ownership percentage by parent					100.00%