GUARANTOR SUBSIDIARIES FINANCIAL INFORMATION - Income Statement (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Revenue and Other Income:
Revenue from contracts with customers	$ 356,982	$ 384,117
Miscellaneous Other Income	13,292	25,887
Gain on Sale of Assets	339	254
Total Revenue and Other Income	370,613	410,258
Costs and Expenses:
Operating and Other Costs	230,112	229,802
Depreciation, Depletion and Amortization	50,724	49,471
Freight Expense	6,662	17,887
Selling, General and Administrative Costs	21,923	13,484
Loss on Debt Extinguishment	23,143	1,426
Interest Expense, net	18,596	21,045
Total Costs and Expenses	351,160	333,115
Earnings Before Income Tax	19,453	77,143
Income Tax (Benefit) Expense	(850)	6,185
Net Income	20,303	70,958
Less: Net Income Attributable to Noncontrolling Interest	5,868	8,550
Net Income Attributable to CONSOL Energy Inc. Shareholders	14,435	62,408
Elimination
Revenue and Other Income:
Miscellaneous Other Income	(44,343)	(77,636)
Gain on Sale of Assets	0	0
Total Revenue and Other Income	(44,343)	(77,636)
Costs and Expenses:
Operating and Other Costs	0	0
Depreciation, Depletion and Amortization	0	0
Freight Expense	0	0
Selling, General and Administrative Costs	0	0
Loss on Debt Extinguishment	0	0
Interest Expense, net	0	0
Total Costs and Expenses	0	0
Earnings Before Income Tax	(44,343)	(77,636)
Income Tax (Benefit) Expense	0	0
Net Income	(44,343)	(77,636)
Less: Net Income Attributable to Noncontrolling Interest	5,868	8,550
Net Income Attributable to CONSOL Energy Inc. Shareholders	(50,211)	(86,186)
Parent Issuer | Reportable Legal Entities
Revenue and Other Income:
Miscellaneous Other Income	53,792	90,304
Gain on Sale of Assets	0	0
Total Revenue and Other Income	53,792	90,304
Costs and Expenses:
Operating and Other Costs	0	0
Depreciation, Depletion and Amortization	0	0
Freight Expense	0	0
Selling, General and Administrative Costs	0	0
Loss on Debt Extinguishment	23,143	1,426
Interest Expense, net	17,064	20,285
Total Costs and Expenses	40,207	21,711
Earnings Before Income Tax	13,585	68,593
Income Tax (Benefit) Expense	(850)	6,185
Net Income	14,435	62,408
Less: Net Income Attributable to Noncontrolling Interest	0	0
Net Income Attributable to CONSOL Energy Inc. Shareholders	14,435	62,408
Guarantor | Reportable Legal Entities
Revenue and Other Income:
Miscellaneous Other Income	2,532	11,018
Gain on Sale of Assets	334	178
Total Revenue and Other Income	275,057	303,089
Costs and Expenses:
Operating and Other Costs	177,603	176,820
Depreciation, Depletion and Amortization	39,507	38,657
Freight Expense	4,997	13,415
Selling, General and Administrative Costs	17,363	10,464
Loss on Debt Extinguishment	0	0
Interest Expense, net	181	944
Total Costs and Expenses	239,651	240,300
Earnings Before Income Tax	35,406	62,789
Income Tax (Benefit) Expense	0	0
Net Income	35,406	62,789
Less: Net Income Attributable to Noncontrolling Interest	0	0
Net Income Attributable to CONSOL Energy Inc. Shareholders	35,406	62,789
Non-Guarantor | Reportable Legal Entities
Revenue and Other Income:
Miscellaneous Other Income	0	0
Gain on Sale of Assets	0	0
Total Revenue and Other Income	0	0
Costs and Expenses:
Operating and Other Costs	415	695
Depreciation, Depletion and Amortization	0	0
Freight Expense	0	0
Selling, General and Administrative Costs	0	0
Loss on Debt Extinguishment	0	0
Interest Expense, net	0	0
Total Costs and Expenses	415	695
Earnings Before Income Tax	(415)	(695)
Income Tax (Benefit) Expense	0	0
Net Income	(415)	(695)
Less: Net Income Attributable to Noncontrolling Interest	0	0
Net Income Attributable to CONSOL Energy Inc. Shareholders	(415)	(695)
Non-Guarantor | CCR Non-Guarantor | Reportable Legal Entities
Revenue and Other Income:
Miscellaneous Other Income	1,311	2,201
Gain on Sale of Assets	5	76
Total Revenue and Other Income	86,107	94,501
Costs and Expenses:
Operating and Other Costs	52,094	52,287
Depreciation, Depletion and Amortization	11,217	10,814
Freight Expense	1,665	4,472
Selling, General and Administrative Costs	4,560	3,020
Loss on Debt Extinguishment	0	0
Interest Expense, net	1,351	(184)
Total Costs and Expenses	70,887	70,409
Earnings Before Income Tax	15,220	24,092
Income Tax (Benefit) Expense		0
Net Income	15,220	24,092
Less: Net Income Attributable to Noncontrolling Interest	0	0
Net Income Attributable to CONSOL Energy Inc. Shareholders	15,220	24,092
Coal Revenue
Revenue and Other Income:
Revenue from contracts with customers	332,502	351,009
Coal Revenue | Elimination
Revenue and Other Income:
Revenue from contracts with customers	0	0
Coal Revenue | Parent Issuer | Reportable Legal Entities
Revenue and Other Income:
Revenue from contracts with customers	0	0
Coal Revenue | Guarantor | Reportable Legal Entities
Revenue and Other Income:
Revenue from contracts with customers	249,376	263,257
Coal Revenue | Non-Guarantor | Reportable Legal Entities
Revenue and Other Income:
Revenue from contracts with customers	0	0
Coal Revenue | Non-Guarantor | CCR Non-Guarantor | Reportable Legal Entities
Revenue and Other Income:
Revenue from contracts with customers	83,126	87,752
Terminal Revenue
Revenue and Other Income:
Revenue from contracts with customers	17,818	15,221
Terminal Revenue | Elimination
Revenue and Other Income:
Revenue from contracts with customers	0	0
Terminal Revenue | Parent Issuer | Reportable Legal Entities
Revenue and Other Income:
Revenue from contracts with customers	0	0
Terminal Revenue | Guarantor | Reportable Legal Entities
Revenue and Other Income:
Revenue from contracts with customers	17,818	15,221
Terminal Revenue | Non-Guarantor | Reportable Legal Entities
Revenue and Other Income:
Revenue from contracts with customers	0	0
Terminal Revenue | Non-Guarantor | CCR Non-Guarantor | Reportable Legal Entities
Revenue and Other Income:
Revenue from contracts with customers	0	0
Freight Revenue
Revenue and Other Income:
Revenue from contracts with customers	6,662	17,887
Freight Revenue | Elimination
Revenue and Other Income:
Revenue from contracts with customers	0	0
Freight Revenue | Parent Issuer | Reportable Legal Entities
Revenue and Other Income:
Revenue from contracts with customers	0	0
Freight Revenue | Guarantor | Reportable Legal Entities
Revenue and Other Income:
Revenue from contracts with customers	4,997	13,415
Freight Revenue | Non-Guarantor | Reportable Legal Entities
Revenue and Other Income:
Revenue from contracts with customers	0	0
Freight Revenue | Non-Guarantor | CCR Non-Guarantor | Reportable Legal Entities
Revenue and Other Income:
Revenue from contracts with customers	$ 1,665	$ 4,472