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

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

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Amount of debt discount to be amortized within one year or within the normal operating cycle, if longer.

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Amount of debt premium to be amortized within one year or the normal operating cycle, if longer.

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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.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

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Long-Term Debt - Schedule of Long-Term Debt (Details) - USD ($)	Sep. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Apr. 30, 2019
Debt Instrument [Line Items]
Long-term debt, net of issuance costs	$ 2,600,462,000		$ 2,754,443,000
Less: Unamortized Debt Issuance Costs	16,940,000		8,990,000
Less: Amounts Due in One Year	22,488,000		0
Long-Term Debt	$ 2,577,974,000		2,754,443,000
Senior Notes Due March 2027
Debt Instrument [Line Items]
Stated rate, debt instrument	7.25%
Debt instrument, face amount	$ 700,000,000		500,000,000
Debt instrument, unamortized premium	6,955,000
Long-term debt, net of issuance costs	$ 706,955,000		500,000,000
Senior Notes Due March 2026
Debt Instrument [Line Items]
Stated rate, debt instrument	6.50%
Debt instrument, face amount	$ 400,000,000		400,000,000
Debt instrument, unamortized discount	4,062,000		4,625,000
Long-term debt, net of issuance costs	$ 395,938,000		395,375,000
Senior Notes Due April 2022
Debt Instrument [Line Items]
Stated rate, debt instrument	5.875%			5.875%
Debt instrument, face amount	$ 363,348,000		894,307,000
Debt instrument, unamortized premium	276,000		1,001,000
Long-term debt, net of issuance costs	$ 363,624,000		895,308,000
Convertible Senior Notes Due May 2026
Debt Instrument [Line Items]
Stated rate, debt instrument	2.25%
Debt instrument, face amount	$ 345,000,000
Debt instrument, unamortized discount	111,621,000
Long-term debt, net of issuance costs	233,379,000		0
Cardinal States Gathering Company Credit Facility
Debt Instrument [Line Items]
Debt instrument, unamortized discount	1,165,000
CSG Holdings II LLC Credit Facility
Debt Instrument [Line Items]
Debt instrument, unamortized discount	460,000
Revolving Credit Facility
Debt Instrument [Line Items]
Debt instrument, face amount					$ 160,000,000	$ 2,100,000,000
Borrowings outstanding	410,000,000		661,000,000
Revolving Credit Facility \| CNX Revolving Credit Facility
Debt Instrument [Line Items]
Long-term debt, net of issuance costs	410,000,000		661,000,000
Revolving Credit Facility \| CNX Midstream Partners LP Revolving Credit Facility
Debt Instrument [Line Items]
Long-term debt, net of issuance costs	343,000,000		311,750,000
Line of Credit
Debt Instrument [Line Items]
Debt instrument, face amount		$ 175,000,000
Line of Credit \| Cardinal States Gathering Company Credit Facility
Debt Instrument [Line Items]
Borrowings outstanding	118,776,000
Long-term debt, net of issuance costs	117,611,000		0
Line of Credit \| CSG Holdings II LLC Credit Facility
Debt Instrument [Line Items]
Borrowings outstanding	47,355,000
Long-term debt, net of issuance costs	$ 46,895,000		$ 0