Acquisitions and Dispositions Pro Forma Financial Information (Details) - Midstream Acquisition [Member] - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2017	Sep. 30, 2017
Business Acquisition [Line Items]
Pro Forma Total Revenue and Other Operating Income	$ 311,272	$ 1,051,683
Pro Forma Net Income from Continuing Operations	11,240	104,219
Less: Pro Forma Net income Attributable to Noncontrolling Interests	18,670	56,804
Pro Forma Net Income(Loss) from Continuing Operations Attributable to CNX	$ (7,430)	$ 47,415
Pro Forma Income Loss per Share from Continuing Operations (Basic) (usd per share)	$ (0.03)	$ 0.21
Pro Forma Income Loss per Share from Continuing Operations (Diluted) (usd per share)	$ (0.04)	$ 0.20

Business Acquisition, Pro Forma Income (Loss), Attributable to Non-Controlling Interests

No definition available.

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- Definition

Business Acquisition, Pro Forma Income (Loss), From Continuing Operations, Attributable to Parent

+ References

No definition available.

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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

The pro forma basic net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(3)
-URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(2)
-URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463

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- Definition

The pro forma diluted net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

+ References

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- Definition

Amount after tax of pro forma income from continuing operations as if the business combination had been completed at the beginning of a period.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(2)
-URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(3)
-URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463

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- Definition

The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

+ References

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