Face (par) amount of debt instrument at time of issuance.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 30
-Section 55
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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

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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

Fair value amount of debt instrument that was repurchased.

+ References

No definition available.

+ Details

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Balance Type:	debit
Period Type:	instant

- Definition

Amount, after accumulated amortization, of debt discount.

+ References

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-Publisher FASB
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-SubTopic 30
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- Definition

Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 50
-Section 40
-Paragraph 2
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- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

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Balance Type:	credit
Period Type:	instant

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

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Long-Term Debt (Details) - USD ($)	3 Months Ended
Long-Term Debt (Details) - USD ($)	Mar. 31, 2018	Mar. 31, 2017	Mar. 08, 2018	Mar. 07, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Gain (loss) on extinguishment of debt	$ 15,635,000	$ (822,000)
Senior Notes due March 2026 [Member]
Debt Instrument [Line Items]
Debt instrument, face amount	400,000,000
Senior Notes Due April 2022 [Member]
Debt Instrument [Line Items]
Debt instrument, face amount	$ 1,314,307,000				$ 1,705,682,000
Stated rate, debt instrument	5.875%	5.875%
Repurchase amount on debt instrument	$ 391,375,000	$ 99,956,000
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Debt instrument, face amount			$ 2,100,000,000	$ 1,500,000,000	1,500,000,000
Revolving Credit Facility			650,000,000
Long-Term Debt	0				$ 0
CNX Midstream Partners LP [Member] \| Senior Notes due March 2026 [Member]
Debt Instrument [Line Items]
Debt instrument, face amount	$ 400,000,000
Stated rate, debt instrument	6.50%
Unamortized bond discount	$ 6,000,000
CNX Midstream Partners LP [Member] \| Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Revolving Credit Facility			$ 600,000,000	$ 250,000,000
Long-Term Debt	$ 20,000,000