Credit Facility, Debt Covenant, Secured Leverage Ratio

No definition available.

Name:	cnx_CreditFacilityDebtCovenantSecuredLeverageRatio
Namespace Prefix:	cnx_
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Balance Type:	na
Period Type:	duration

- Definition

Debt Instrument, Borrowing Base

+ References

No definition available.

+ Details

Name:	cnx_DebtInstrumentBorrowingBase
Namespace Prefix:	cnx_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Debt Instrument, Interest Coverage Ratio

+ References

No definition available.

+ Details

Name:	cnx_DebtInstrumentInterestCoverageRatio
Namespace Prefix:	cnx_
Data Type:	xbrli:decimalItemType
Balance Type:	na
Period Type:	duration

- Definition

Debt Instrument, Minimum Threshold to Activate Springing Maturity Date

+ References

No definition available.

+ Details

Name:	cnx_DebtInstrumentMinimumThresholdtoActivateSpringingMaturityDate
Namespace Prefix:	cnx_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Letters Of Credit, Amount Outstanding

+ References

No definition available.

+ Details

Name:	cnx_LettersOfCreditAmountOutstanding
Namespace Prefix:	cnx_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Line of Credit Facility, Accordion Feature, Increase Limit

+ References

No definition available.

+ Details

Name:	cnx_LineofCreditFacilityAccordionFeatureIncreaseLimit
Namespace Prefix:	cnx_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Maximum Interest Ratio per Credit Facility Covenant

+ References

No definition available.

+ Details

Name:	cnx_MaximumInterestRatioperCreditFacilityCovenant
Namespace Prefix:	cnx_
Data Type:	xbrli:decimalItemType
Balance Type:	na
Period Type:	duration

- Definition

minimum current ratio per credit facility

+ References

No definition available.

+ Details

Name:	cnx_Minimumcurrentratiopercreditfacility
Namespace Prefix:	cnx_
Data Type:	xbrli:decimalItemType
Balance Type:	na
Period Type:	instant

- Definition

Percentage to Mortgage, Value of Proved Developing Producing Reserves

+ References

No definition available.

+ Details

Name:	cnx_PercentagetoMortgageValueofProvedDevelopingProducingReserves
Namespace Prefix:	cnx_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Percentage to Mortgage, Value of Proved Reserves

+ References

No definition available.

+ Details

Name:	cnx_PercentagetoMortgageValueofProvedReserves
Namespace Prefix:	cnx_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=64930739&loc=d3e28878-108400

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399

+ Details

Name:	us-gaap_DebtInstrumentFaceAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

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

+ References

+ Details

Name:	us-gaap_DebtInstrumentInterestRateStatedPercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- 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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

+ Details

Name:	us-gaap_LineOfCredit
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
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

+ Details

Name:	us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

+ Details

Name:	us-gaap_LineOfCreditFacilityRemainingBorrowingCapacity
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- 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.

+ Details

Name:	us-gaap_ShortTermDebtLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_CreditFacilityAxis=us-gaap_RevolvingCreditFacilityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=cnx_A8.00SeniorNotesdue2023Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=cnx_A5.875SeniorNotesdue2022Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_OwnershipAxis=cnx_CNXMidstreamPartnersLPMember
Namespace Prefix:
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Balance Type:
Period Type:

- Details

Name:	us-gaap_OwnershipAxis=cnx_CNXMMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RangeAxis=us-gaap_MinimumMember
Namespace Prefix:
Data Type:	na
Balance Type:
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- Details

Name:	us-gaap_RangeAxis=us-gaap_MaximumMember
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Revolving Credit Facilities (Details)		3 Months Ended
Revolving Credit Facilities (Details)	Mar. 08, 2018 USD ($)	Mar. 31, 2018 USD ($)	Mar. 07, 2018 USD ($)	Dec. 31, 2017 USD ($)
Short-term Debt [Line Items]
Percentage to mortgage, value of proved Reserves		80.00%
Percentage to mortgage, value of proved developing producing reserves		80.00%
Revolving Credit Facility [Member]
Short-term Debt [Line Items]
Credit facility, face amount	$ 2,100,000,000		$ 1,500,000,000	$ 1,500,000,000
Accordion feature, increased commitment	3,000,000,000
Initial borrowing base	2,500,000,000		2,000,000,000
Revolving Credit Facility	$ 650,000,000
Minimum threshold to activate springing maturity date		$ 500,000,000
Maximum net leverage ratio	4.00
Minimum current ratio	1
Borrowings outstanding		0		0
Letters of credit outstanding		253,167,000		239,072,000
Borrowings and issuance of letters of credit remaining capacity		1,846,833,000		$ 1,260,928,000
8.00% Senior Notes due 2023 [Member]
Short-term Debt [Line Items]
Stated rate, debt instrument	8.00%
5.875% Senior Notes due 2022 [Member]
Short-term Debt [Line Items]
Stated rate, debt instrument	5.875%
CNX Midstream Partners LP [Member] \| Revolving Credit Facility [Member]
Short-term Debt [Line Items]
Revolving Credit Facility	$ 600,000,000		$ 250,000,000
Borrowings outstanding		$ 20,000,000
CNXM [Member] \| Revolving Credit Facility [Member]
Short-term Debt [Line Items]
Secured Leverage Ratio	3.50
Interest Coverage Ratio	2.50
CNXM [Member] \| Minimum [Member] \| Revolving Credit Facility [Member]
Short-term Debt [Line Items]
Maximum net leverage ratio	4.75
CNXM [Member] \| Maximum [Member] \| Revolving Credit Facility [Member]
Short-term Debt [Line Items]
Maximum net leverage ratio	5.50