Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Net (Loss) Income	$ (13,214)	$ 93,558	$ 178,785
Other Comprehensive Income (Loss):
Amortization of Prior Service Credits (net of tax: $619, $697, $662)	(1,786)	(2,075)	(2,246)
Recognized Net Actuarial Loss (net of tax: $(5,596), $(3,958), $(5,590))	16,161	11,773	18,960
Other Comprehensive (Loss) Gain before Reclassifications (net of tax: $109, $11,690, $(14,986))	(145)	(34,830)	49,627
Unrecognized Loss on Derivatives:
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), after Reclassification and Tax, Total	(2,004)	(117)	0
Other Comprehensive Income (Loss)	12,226	(25,249)	66,341
Comprehensive (Loss) Income	(988)	68,309	245,126
Less: Comprehensive (Loss) Income Attributable to Noncontrolling Interest	(3,400)	17,551	25,803
Comprehensive Income Attributable to CONSOL Energy Inc. Shareholders	$ 2,412	$ 50,758	$ 219,323