LONG-TERM DEBT (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Debt Instrument [Line Items]
Less: Unamortized Debt Issuance Costs	$ 3,568	$ 4,343
Total Amounts Committed	289,975	302,200
Less: Amounts Due in One Year	373	373
Long-Term Debt	289,602	301,827
Current portion of capital lease obligations	3,147	3,703
Line of Credit \| Revolving Credit Facility - CONSOL Coal Resources LP
Debt Instrument [Line Items]
Long-term debt, gross	188,000	201,000
Loans Payable \| MEDCO Revenue Bonds in Series due September 2025 at 5.75%
Debt Instrument [Line Items]
Long-term debt, gross	$ 102,865	102,865
Stated interest rate	5.75%
Loans Payable \| Advance Royalty Commitments (7.73% Weighted Average Interest Rate)
Debt Instrument [Line Items]
Long-term debt, gross	$ 2,678	$ 2,678
Weighted average interest rate	7.73%

Amount of capital lease obligation due within one year or the normal operating cycle, if longer.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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

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Weighted average interest rate of debt outstanding.

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Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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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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