Note 16 - Segment Information - Industry Segment (Details) - USD ($) $ in Thousands		3 Months Ended
		Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021
Revenue		$ 536,154	$ 330,760
Adjusted EBITDA(a)	[1]	169,230	106,715
Assets, Total		2,714,960	2,520,560	$ 2,573,517
Depreciation, Depletion and Amortization		55,954	59,897
Capital Expenditures		36,643	13,800
Coal Revenue [Member]
Revenue		476,368	285,535
Terminal Revenue [Member]
Revenue		21,397	18,212
Freight Revenue [Member]
Revenue		38,389	27,013
Intersegment Eliminations [Member]
Revenue		0	0
Adjusted EBITDA(a)	[1]	0	0
Assets, Total		0	0
Depreciation, Depletion and Amortization		0	0
Capital Expenditures		0	0
Intersegment Eliminations [Member] | Coal Revenue [Member]
Revenue		0	0
Intersegment Eliminations [Member] | Terminal Revenue [Member]
Revenue		0	0
Intersegment Eliminations [Member] | Freight Revenue [Member]
Revenue		0	0
Pennsylvania Mining Complex [Member]
Adjusted EBITDA(a)		158,258	99,185
Depreciation, Depletion and Amortization		50,956	54,781
Pennsylvania Mining Complex [Member] | Operating Segments [Member]
Revenue		511,349	311,478
Adjusted EBITDA(a)	[1]	158,258	99,185
Assets, Total		1,734,316	1,855,878
Depreciation, Depletion and Amortization		50,956	54,781
Capital Expenditures		12,978	12,579
Pennsylvania Mining Complex [Member] | Operating Segments [Member] | Coal Revenue [Member]
Revenue		472,960	284,465
Pennsylvania Mining Complex [Member] | Operating Segments [Member] | Terminal Revenue [Member]
Revenue		0	0
Pennsylvania Mining Complex [Member] | Operating Segments [Member] | Freight Revenue [Member]
Revenue		38,389	27,013
CONSOL Marine Terminal [Member]
Adjusted EBITDA(a)		14,477	11,961
Depreciation, Depletion and Amortization		1,165	1,214
CONSOL Marine Terminal [Member] | Operating Segments [Member]
Revenue		21,397	18,212
Adjusted EBITDA(a)	[1]	14,477	11,961
Assets, Total		80,135	106,603
Depreciation, Depletion and Amortization		1,165	1,214
Capital Expenditures		172	60
CONSOL Marine Terminal [Member] | Operating Segments [Member] | Coal Revenue [Member]
Revenue		0	0
CONSOL Marine Terminal [Member] | Operating Segments [Member] | Terminal Revenue [Member]
Revenue		21,397	18,212
CONSOL Marine Terminal [Member] | Operating Segments [Member] | Freight Revenue [Member]
Revenue		0	0
Other Segments [Member]
Adjusted EBITDA(a)		(3,505)	(4,431)
Depreciation, Depletion and Amortization		3,833	3,902
Other Segments [Member] | Operating Segments [Member]
Revenue		3,408	1,070
Adjusted EBITDA(a)	[1]	(3,505)	(4,431)
Assets, Total		900,509	558,079
Depreciation, Depletion and Amortization		3,833	3,902
Capital Expenditures		23,493	1,161
Other Segments [Member] | Operating Segments [Member] | Coal Revenue [Member]
Revenue		3,408	1,070
Other Segments [Member] | Operating Segments [Member] | Terminal Revenue [Member]
Revenue		0	0
Other Segments [Member] | Operating Segments [Member] | Freight Revenue [Member]
Revenue		$ 0	$ 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.