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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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.

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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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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.

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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 ($)	Mar. 31, 2020	Dec. 31, 2019	Apr. 30, 2019	Mar. 31, 2019
Debt Instrument [Line Items]
Long-term debt, gross	$ 2,660,599,000	$ 2,754,443,000
Less: Unamortized Debt Issuance Costs	16,018,000	8,990,000
Less: Amounts Due in One Year	20,451,000	0
Long-Term Debt	$ 2,640,148,000	2,754,443,000
Senior Notes due April 2022
Debt Instrument [Line Items]
Stated rate, debt instrument	5.875%			5.875%
Debt instrument, face amount	$ 822,973,000	894,307,000
Debt instrument, unamortized premium	822,000	1,001,000
Long-term debt, gross	$ 823,795,000	895,308,000
Senior Notes due March 2027
Debt Instrument [Line Items]
Stated rate, debt instrument	7.25%			7.25%
Debt instrument, face amount				$ 500,000,000
Long-term debt, gross	$ 500,000,000	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	4,438,000	4,625,000
Long-term debt, gross	395,562,000	395,375,000
Cardinal States Facility
Debt Instrument [Line Items]
Debt instrument, unamortized discount	1,243,000
CSG Holdings Facility
Debt Instrument [Line Items]
Debt instrument, unamortized discount	497,000
Line of Credit
Debt Instrument [Line Items]
Debt instrument, face amount	175,000,000
Line of Credit \| Cardinal States Facility
Debt Instrument [Line Items]
Line of credit facility maximum borrowing capacity	125,000,000
Long-term debt, gross	123,757,000	0
Line of Credit \| CSG Holdings Facility
Debt Instrument [Line Items]
Line of credit facility maximum borrowing capacity	50,000,000
Long-term debt, gross	49,503,000	0
Revolving Credit Facility
Debt Instrument [Line Items]
Debt instrument, face amount	160,000,000		$ 2,100,000,000
Line of credit facility maximum borrowing capacity			$ 650,000,000
Revolving Credit Facility \| CNX Revolving Credit Facility
Debt Instrument [Line Items]
Long-term debt, gross	437,000,000	661,000,000
Revolving Credit Facility \| CNX Midstream Partners LP Revolving Credit Facility
Debt Instrument [Line Items]
Long-term debt, gross	$ 347,000,000	$ 311,750,000