Note 15 - Segment Information - Industry Segment (Details) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Dec. 31, 2021
Revenue		$ 530,067	$ 292,016	$ 1,671,103	$ 925,998
Adjusted EBITDA	[1]	180,881	66,564	566,450	257,696
Assets, Total		2,722,276	2,589,747	2,722,276	2,589,747	$ 2,573,517
Depreciation, Depletion and Amortization		54,773	55,977	168,607	168,073
Capital Expenditures		58,395	45,863	134,456	103,318
Coal Revenue [Member]
Revenue		472,608	258,560	1,481,668	803,927
Terminal Revenue [Member]
Revenue		14,840	14,108	58,016	49,700
Freight Revenue [Member]
Revenue		42,619	19,348	131,419	72,371
Intersegment Eliminations [Member]
Revenue		0	0	0	0
Adjusted EBITDA	[1]	0	0	0	0
Assets, Total		0	0	0	0
Depreciation, Depletion and Amortization		0	0	0	0
Capital Expenditures		0	0	0	0
Intersegment Eliminations [Member] | Coal Revenue [Member]
Revenue		0	0	0	0
Intersegment Eliminations [Member] | Terminal Revenue [Member]
Revenue		0	0	0	0
Intersegment Eliminations [Member] | Freight Revenue [Member]
Revenue		0	0	0	0
Pennsylvania Mining Complex [Member]
Adjusted EBITDA		179,516	69,492	541,753	246,943
Depreciation, Depletion and Amortization		49,316	50,837	149,737	155,787
Pennsylvania Mining Complex [Member] | Operating Segments [Member]
Revenue		508,311	275,674	1,585,989	871,645
Adjusted EBITDA	[1]	179,516	69,492	541,753	246,943
Assets, Total		1,782,514	1,763,319	1,782,514	1,763,319
Depreciation, Depletion and Amortization		49,316	50,837	149,737	155,787
Capital Expenditures		50,112	30,665	84,763	83,118
Pennsylvania Mining Complex [Member] | Operating Segments [Member] | Coal Revenue [Member]
Revenue		465,693	256,326	1,457,595	799,274
Pennsylvania Mining Complex [Member] | Operating Segments [Member] | Terminal Revenue [Member]
Revenue		0	0	0	0
Pennsylvania Mining Complex [Member] | Operating Segments [Member] | Freight Revenue [Member]
Revenue		42,618	19,348	128,394	72,371
CONSOL Marine Terminal [Member]
Adjusted EBITDA		8,328	7,319	37,882	30,244
Depreciation, Depletion and Amortization		1,149	1,202	3,456	3,616
CONSOL Marine Terminal [Member] | Operating Segments [Member]
Revenue		14,840	14,108	58,016	49,700
Adjusted EBITDA	[1]	8,328	7,319	37,882	30,244
Assets, Total		80,534	105,134	80,534	105,134
Depreciation, Depletion and Amortization		1,149	1,202	3,456	3,616
Capital Expenditures		2,248	453	2,608	565
CONSOL Marine Terminal [Member] | Operating Segments [Member] | Coal Revenue [Member]
Revenue		0	0	0	0
CONSOL Marine Terminal [Member] | Operating Segments [Member] | Terminal Revenue [Member]
Revenue		14,840	14,108	58,016	49,700
CONSOL Marine Terminal [Member] | Operating Segments [Member] | Freight Revenue [Member]
Revenue		0	0	0	0
Other Segments [Member]
Adjusted EBITDA		(6,963)	(10,247)	(13,185)	(19,491)
Depreciation, Depletion and Amortization		4,308	3,938	15,414	8,670
Other Segments [Member] | Operating Segments [Member]
Revenue		6,916	2,234	27,098	4,653
Adjusted EBITDA	[1]	(6,963)	(10,247)	(13,185)	(19,491)
Assets, Total		859,228	721,294	859,228	721,294
Depreciation, Depletion and Amortization		4,308	3,938	15,414	8,670
Capital Expenditures		6,035	14,745	47,085	19,635
Other Segments [Member] | Operating Segments [Member] | Coal Revenue [Member]
Revenue		6,915	2,234	24,073	4,653
Other Segments [Member] | Operating Segments [Member] | Terminal Revenue [Member]
Revenue		0	0	0	0
Other Segments [Member] | Operating Segments [Member] | Freight Revenue [Member]
Revenue		$ 1	$ 0	$ 3,025	$ 0

[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.