Debt Instrument, Purchase of Outstanding Debt

No definition available.

Name:	cnx_DebtInstrumentPurchaseofOutstandingDebt
Namespace Prefix:	cnx_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

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

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
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+ Details

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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

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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+ Details

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Balance Type:	na
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

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount, after accumulated amortization, of debt discount.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
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+ Details

Name:	us-gaap_DebtInstrumentUnamortizedDiscount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

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

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-Publisher FASB
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+ Details

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Balance Type:	credit
Period Type:	duration

- Details

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Balance Type:
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- Details

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- Details

Name:	srt_OwnershipAxis=cnx_CNXMMember
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Long-Term Debt - Narrative (Details) - USD ($)	3 Months Ended		9 Months Ended
Long-Term Debt - Narrative (Details) - USD ($)	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Apr. 30, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Gain (loss) on extinguishment of debt	$ 0	$ (15,385,000)	$ (7,614,000)	$ (54,433,000)
Senior Notes due March 2027
Debt Instrument [Line Items]
Debt instrument, face amount	$ 500,000,000		$ 500,000,000
Stated rate, debt instrument	7.25%		7.25%
Senior Notes due April 2022
Debt Instrument [Line Items]
Debt instrument, face amount	$ 894,307,000		$ 894,307,000			$ 1,294,307,000
Stated rate, debt instrument	5.875%	5.875%	5.875%	5.875%
Purchase of outstanding debt			$ 400,000,000	$ 391,375,000
Gain (loss) on extinguishment of debt			(7,614,000)	$ (15,635,000)
Senior Notes due March 2026
Debt Instrument [Line Items]
Debt instrument, face amount	$ 400,000,000		400,000,000			$ 400,000,000
Stated rate, debt instrument		6.50%		6.50%
Senior Notes due April 2023
Debt Instrument [Line Items]
Stated rate, debt instrument		8.00%		8.00%
Purchase of outstanding debt		$ 200,000,000		$ 500,000,000
Gain (loss) on extinguishment of debt		(15,385,000)		(38,798,000)
Revolving Credit Facility
Debt Instrument [Line Items]
Debt instrument, face amount	$ 160,000		$ 160,000		$ 2,100,000,000
CNXM \| Senior Notes due March 2026
Debt Instrument [Line Items]
Debt instrument, face amount		400,000,000		400,000,000
Unamortized bond discount		$ 6,000,000		$ 6,000,000