Business Acquisition, Number Of Additional Wells Added

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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

Leased area representing summation of fractional ownership working interest to whole on which oil and gas wells have not been drilled or completed that would permit production of economic quantities of oil and gas. Excludes area of undrilled acreage held by production under terms of lease.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher SEC
-Name Regulation S-K (SK)
-Number 229
-Section 1208
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Number of producing gas wells and gas wells capable of production with working interest ownership.

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-Name Regulation S-K (SK)
-Number 229
-Section 1208
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- Definition

Area of land held.

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No definition available.

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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 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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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.

+ References

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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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 aggregate amount of write-downs for impairments recognized during the period for long-lived assets held for abandonment, exchange or sale.

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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 associated with the deconsolidation of a previously consolidated subsidiary or the sale of investment in consolidated subsidiaries (generally greater than 50 percent).

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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 cash inflow from the sale of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale.

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Acquisitions and Dispositions Narrative (Details) $ in Thousands					1 Months Ended					3 Months Ended	12 Months Ended
	Aug. 31, 2018 USD ($) a	May 02, 2018 USD ($) well	Mar. 30, 2018 USD ($)	Jan. 03, 2018 USD ($)	May 31, 2018 USD ($)	Sep. 30, 2017 USD ($) a	Jun. 30, 2017 USD ($) a well	May 31, 2017 USD ($) a	Apr. 30, 2017 USD ($)	Sep. 30, 2018 USD ($)	Dec. 31, 2019 USD ($) a well	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 14, 2017
Business Acquisition [Line Items]
Proved Undeveloped Acreage \| a											28,916,000
Proceeds from sale of assets											$ 45,160	$ 511,767	$ 414,185
Net gain (loss) on sale											35,563	157,015	188,063
Impairment of other intangibles											0	18,650	0
Gain on remeasurement of fair value of previously held equity interest											$ 0	623,663	0
Producing Gas Wells (including Gob Wells) \| well							12				6,512,000
Drilled but uncompleted wells \| well							15
Midstream
Business Acquisition [Line Items]
Cash consideration transferred				$ 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
Business Acquisition [Line Items]
Proved Undeveloped Acreage \| a	26,000
Proceeds from sale of assets	$ 381,124
Net gain (loss) on sale	$ 130,710
Asset Exchange Agreement with HG Energy
Business Acquisition [Line Items]
Net gain (loss) on sale		$ 286
Cash proceeds from Asset Exchange Agreement		$ 7,000
Number of wells added to existing commitment \| well		40
Shallow Oil, Gas, and CBM Assets in Pennsylvania and West Virginia
Business Acquisition [Line Items]
Net gain (loss) on sale			$ 4,227
Cash consideration received in sale of oil and gas assets			89,921
Asset retirement obligations assumed			$ 196,514
Surface Land, Colorado
Business Acquisition [Line Items]
Net gain (loss) on sale						$ 18,758
Net acres of land \| a						22,000
Proceeds sale of land						$ 23,703
Marcellus Shale Acres, Allegheny and Westmoreland County
Business Acquisition [Line Items]
Net gain (loss) on sale										$ 15,251
Net acres of land \| a						7,500
Proceeds sale of land										$ 36,649
Marcellus And Utica Shale, Allegheny, Washington And Westmoreland Counties
Business Acquisition [Line Items]
Net gain (loss) on sale							$ 58,541
Net acres of land \| a							11,100
Proceeds sale of land							$ 83,500
Marcellus And Utica Acres, Doddridge And Wetzel Counties
Business Acquisition [Line Items]
Net gain (loss) on sale							$ 9,430
Net acres of land \| a							11,000
Proceeds sale of land							$ 125,507
Utica Point Pleasant Shale Acres, Jefferson, Belmont And Guernsey Counties
Business Acquisition [Line Items]
Net gain (loss) on sale								$ 72,346
Net acres of land \| a								6,300
Proceeds sale of land								$ 76,585
Knox and Coalfield
Business Acquisition [Line Items]
Net gain (loss) on sale												606
Impairment on Assets Held for Sale													$ 137,865
CNX Gathering
Business Acquisition [Line Items]
Ownership percentage in equity method investment											100.00%			50.00%
Customer Relationships \| Midstream
Business Acquisition [Line Items]
Impairment of other intangibles					$ 18,650							$ 18,650
CONE Midstream GP LLC
Business Acquisition [Line Items]
Ownership percentage by parent														100.00%
Discontinued Operations, Disposed of by Sale \| Knox and Coalfield
Business Acquisition [Line Items]
Proceeds from sale of subsidiary, previously classified as held for sale									$ 19,055