GUARANTOR SUBSIDIARIES FINANCIAL INFORMATION - Condensed Statement of Cash Flows (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Condensed Cash Flow Statements, Captions [Line Items]
Net Cash Provided by (Used in) Operating Activities	$ 82,171	$ 115,733
Cash Flows from Investing Activities:
Capital Expenditures	(34,171)	(21,956)
Proceeds from Sales of Assets	311	393
(Investments in), net of Distributions from, Subsidiaries	0	0
Net Cash Used in Investing Activities	(33,860)	(21,563)
Cash Flows from Financing Activities:
Payments on Finance Leases	(4,537)
Payments on Finance Leases		(1,366)
Net (Payments on) Proceeds from Related Party Long-Term Notes	0	0
Distributions to Noncontrolling Interest	(5,559)	(5,587)
Shares/Units Withheld for Taxes	(4,743)	(2,788)
Intercompany Contributions/(Distributions)		0
Spin Distribution to CNX Resources		(18,234)
Repurchases of Common Stock	0	(1,285)
Debt-Related Financing Fees	(18,514)	(1,170)
Net Cash Used in Financing Activities	(136,478)	(56,430)
Term Loan A
Cash Flows from Financing Activities:
Proceeds from (Payments on) loans	26,250	(15,000)
Term Loan B
Cash Flows from Financing Activities:
Proceeds from (Payments on) loans	(122,375)	(1,000)
Senior Secured Second Lien Notes due 2025
Cash Flows from Financing Activities:
Proceeds from (Payments on) loans	(7,000)	(10,000)
Elimination
Condensed Cash Flow Statements, Captions [Line Items]
Net Cash Provided by (Used in) Operating Activities	0	0
Cash Flows from Investing Activities:
Capital Expenditures	0	0
Proceeds from Sales of Assets	0	0
(Investments in), net of Distributions from, Subsidiaries	(8,846)	0
Net Cash Used in Investing Activities	(8,846)	0
Cash Flows from Financing Activities:
Payments on Finance Leases	0
Payments on Finance Leases		0
Net (Payments on) Proceeds from Related Party Long-Term Notes	1,500	9,583
Distributions to Noncontrolling Interest	8,846	8,759
Shares/Units Withheld for Taxes	0	0
Intercompany Contributions/(Distributions)		0
Spin Distribution to CNX Resources		0
Repurchases of Common Stock		0
Debt-Related Financing Fees	0	0
Net Cash Used in Financing Activities	10,346	18,342
Elimination \| Term Loan A
Cash Flows from Financing Activities:
Proceeds from (Payments on) loans	0	0
Elimination \| Term Loan B
Cash Flows from Financing Activities:
Proceeds from (Payments on) loans	0	0
Elimination \| Senior Secured Second Lien Notes due 2025
Cash Flows from Financing Activities:
Proceeds from (Payments on) loans	0	0
Parent Issuer \| Reportable Legal Entities
Condensed Cash Flow Statements, Captions [Line Items]
Net Cash Provided by (Used in) Operating Activities	107,358	(2,305)
Cash Flows from Investing Activities:
Capital Expenditures	0	0
Proceeds from Sales of Assets	0	0
(Investments in), net of Distributions from, Subsidiaries	(65,421)	(2,048)
Net Cash Used in Investing Activities	(65,421)	(2,048)
Cash Flows from Financing Activities:
Payments on Finance Leases	0
Payments on Finance Leases		0
Net (Payments on) Proceeds from Related Party Long-Term Notes	0	0
Distributions to Noncontrolling Interest	0	0
Shares/Units Withheld for Taxes	0	0
Intercompany Contributions/(Distributions)		72,317
Spin Distribution to CNX Resources		(1,595)
Repurchases of Common Stock		(1,285)
Debt-Related Financing Fees	(18,514)	(755)
Net Cash Used in Financing Activities	(121,639)	42,682
Parent Issuer \| Reportable Legal Entities \| Term Loan A
Cash Flows from Financing Activities:
Proceeds from (Payments on) loans	26,250	(15,000)
Parent Issuer \| Reportable Legal Entities \| Term Loan B
Cash Flows from Financing Activities:
Proceeds from (Payments on) loans	(122,375)	(1,000)
Parent Issuer \| Reportable Legal Entities \| Senior Secured Second Lien Notes due 2025
Cash Flows from Financing Activities:
Proceeds from (Payments on) loans	(7,000)	(10,000)
Guarantor \| Reportable Legal Entities
Condensed Cash Flow Statements, Captions [Line Items]
Net Cash Provided by (Used in) Operating Activities	(50,405)	88,774
Cash Flows from Investing Activities:
Capital Expenditures	(26,078)	(17,027)
Proceeds from Sales of Assets	311	318
(Investments in), net of Distributions from, Subsidiaries	74,267	2,048
Net Cash Used in Investing Activities	48,500	(14,661)
Cash Flows from Financing Activities:
Payments on Finance Leases	(3,599)
Payments on Finance Leases		(999)
Net (Payments on) Proceeds from Related Party Long-Term Notes	0	0
Distributions to Noncontrolling Interest	0	0
Shares/Units Withheld for Taxes	(3,863)	(1,889)
Intercompany Contributions/(Distributions)		(72,317)
Spin Distribution to CNX Resources		(16,639)
Repurchases of Common Stock		0
Debt-Related Financing Fees	0	(415)
Net Cash Used in Financing Activities	(7,462)	(92,259)
Guarantor \| Reportable Legal Entities \| Term Loan A
Cash Flows from Financing Activities:
Proceeds from (Payments on) loans	0	0
Guarantor \| Reportable Legal Entities \| Term Loan B
Cash Flows from Financing Activities:
Proceeds from (Payments on) loans	0	0
Guarantor \| Reportable Legal Entities \| Senior Secured Second Lien Notes due 2025
Cash Flows from Financing Activities:
Proceeds from (Payments on) loans	0	0
Non-Guarantor \| Reportable Legal Entities
Condensed Cash Flow Statements, Captions [Line Items]
Net Cash Provided by (Used in) Operating Activities	0	0
Cash Flows from Investing Activities:
Capital Expenditures	0	0
Proceeds from Sales of Assets	0	0
(Investments in), net of Distributions from, Subsidiaries	0	0
Net Cash Used in Investing Activities	0	0
Cash Flows from Financing Activities:
Payments on Finance Leases	0
Payments on Finance Leases		0
Net (Payments on) Proceeds from Related Party Long-Term Notes	0	0
Distributions to Noncontrolling Interest	0	0
Shares/Units Withheld for Taxes	0	0
Intercompany Contributions/(Distributions)		0
Spin Distribution to CNX Resources		0
Repurchases of Common Stock		0
Debt-Related Financing Fees	0	0
Net Cash Used in Financing Activities	0	0
Non-Guarantor \| Reportable Legal Entities \| Term Loan A
Cash Flows from Financing Activities:
Proceeds from (Payments on) loans	0	0
Non-Guarantor \| Reportable Legal Entities \| Term Loan B
Cash Flows from Financing Activities:
Proceeds from (Payments on) loans	0	0
Non-Guarantor \| Reportable Legal Entities \| Senior Secured Second Lien Notes due 2025
Cash Flows from Financing Activities:
Proceeds from (Payments on) loans	0	0
Non-Guarantor \| CCR Non-Guarantor \| Reportable Legal Entities
Condensed Cash Flow Statements, Captions [Line Items]
Net Cash Provided by (Used in) Operating Activities	25,218	29,264
Cash Flows from Investing Activities:
Capital Expenditures	(8,093)	(4,929)
Proceeds from Sales of Assets	0	75
(Investments in), net of Distributions from, Subsidiaries	0	0
Net Cash Used in Investing Activities	(8,093)	(4,854)
Cash Flows from Financing Activities:
Payments on Finance Leases	(938)
Payments on Finance Leases		(367)
Net (Payments on) Proceeds from Related Party Long-Term Notes	(1,500)	(9,583)
Distributions to Noncontrolling Interest	(14,405)	(14,346)
Shares/Units Withheld for Taxes	(880)	(899)
Intercompany Contributions/(Distributions)		0
Spin Distribution to CNX Resources		0
Repurchases of Common Stock		0
Debt-Related Financing Fees	0	0
Net Cash Used in Financing Activities	(17,723)	(25,195)
Non-Guarantor \| CCR Non-Guarantor \| Reportable Legal Entities \| Term Loan A
Cash Flows from Financing Activities:
Proceeds from (Payments on) loans	0	0
Non-Guarantor \| CCR Non-Guarantor \| Reportable Legal Entities \| Term Loan B
Cash Flows from Financing Activities:
Proceeds from (Payments on) loans	0	0
Non-Guarantor \| CCR Non-Guarantor \| Reportable Legal Entities \| Senior Secured Second Lien Notes due 2025
Cash Flows from Financing Activities:
Proceeds from (Payments on) loans	$ 0	$ 0

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