Note 15 - Segment Information - Adjusted EBITDA (Details) - USD ($) $ in Thousands		3 Months Ended						9 Months Ended
		Sep. 30, 2022	Jun. 30, 2022	Mar. 31, 2022	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Sep. 30, 2022	Sep. 30, 2021
Net (Loss) Income		$ 152,121	$ 126,291	$ (4,450)	$ (113,789)	$ 4,172	$ 26,404	$ 273,962	$ (83,213)
Income Tax Expense		39,414			(40,258)			59,115	(43,966)
Interest Expense, net		11,962			16,045			39,435	47,493
Interest Income		(1,541)			(737)			(4,309)	(2,406)
Depreciation, Depletion and Amortization		54,773			55,977			168,607	168,073
Stock-Based Compensation		1,224			1,888			6,694	4,607
Loss on Debt Extinguishment		(674)			(132)			(4,361)	657
Equity Affiliate Adjustments		3,500
Fair Value Adjustment of Commodity Derivative Instruments		(81,246)			147,306			15,085	167,743
Adjusted EBITDA	[1]	180,881			66,564			566,450	257,696
Income Tax Expense (Benefit), Total		39,414			(40,258)			59,115	(43,966)
Equity Affiliate Adjustments								3,500
Pension Settlement									22
Pennsylvania Mining Complex [Member]
Net (Loss) Income		210,907			(130,599)			372,408	(81,983)
Income Tax Expense		0			0			0	0
Interest Expense, net		(52)			305			205	1,425
Interest Income		(437)			0			(1,304)	(36)
Depreciation, Depletion and Amortization		49,316			50,837			149,737	155,787
Stock-Based Compensation		1,028			1,643			5,622	4,007
Loss on Debt Extinguishment		(0)			(0)			(0)	(0)
Equity Affiliate Adjustments		0
Fair Value Adjustment of Commodity Derivative Instruments		(81,246)			147,306			15,085	167,743
Adjusted EBITDA		179,516			69,492			541,753	246,943
Income Tax Expense (Benefit), Total		0			0			0	0
Equity Affiliate Adjustments								0
Pension Settlement									0
CONSOL Marine Terminal [Member]
Net (Loss) Income		5,602			4,506			29,569	21,836
Income Tax Expense		0			0			0	0
Interest Expense, net		1,528			1,535			4,589	4,608
Interest Income		0			0			0	0
Depreciation, Depletion and Amortization		1,149			1,202			3,456	3,616
Stock-Based Compensation		49			76			268	184
Loss on Debt Extinguishment		(0)			(0)			(0)	(0)
Equity Affiliate Adjustments		0
Fair Value Adjustment of Commodity Derivative Instruments		0			0			0	0
Adjusted EBITDA		8,328			7,319			37,882	30,244
Income Tax Expense (Benefit), Total		0			0			0	0
Equity Affiliate Adjustments								0
Pension Settlement									0
Other Segments [Member]
Net (Loss) Income		(64,388)			12,304			(128,015)	(23,066)
Income Tax Expense		39,414			(40,258)			59,115	(43,966)
Interest Expense, net		10,486			14,205			34,641	41,460
Interest Income		(1,104)			(737)			(3,005)	(2,370)
Depreciation, Depletion and Amortization		4,308			3,938			15,414	8,670
Stock-Based Compensation		147			169			804	416
Loss on Debt Extinguishment		(674)			(132)			(4,361)	657
Equity Affiliate Adjustments		3,500
Fair Value Adjustment of Commodity Derivative Instruments		0			0			0	0
Adjusted EBITDA		(6,963)			(10,247)			(13,185)	(19,491)
Income Tax Expense (Benefit), Total		$ 39,414			$ (40,258)			59,115	(43,966)
Equity Affiliate Adjustments								$ 3,500
Pension Settlement									$ 22

[1] Refer to “Reconciliation of Segment Information to Consolidated Amounts” for the reconciliation of Adjusted EBITDA, a non-GAAP measure, to its most directly comparable GAAP measure.