Note 16 - Coal Workers' Pneumoconiosis and Workers' Compensation - Schedule of Expected Benefit Payments (Details) $ in Thousands	Dec. 31, 2021 USD ($)
2022	$ 11,504
2023	11,395
2024	11,371
2025	11,443
2026	11,525
Year 2027-2031	58,808
Coal Workers Pneumoconiosis [Member]
2022	12,398
2023	12,119
2024	11,917
2025	11,603
2026	11,395
Year 2027-2031	56,278
Actuarial Benefits [Member]
2022	9,113
2023	8,944
2024	8,859
2025	8,868
2026	8,886
Year 2027-2031	44,589
Other Benefits [Member]
2022	2,391
2023	2,451
2024	2,512
2025	2,575
2026	2,639
Year 2027-2031	$ 14,219

Amount of benefit for defined benefit plan expected to be paid in five fiscal years after fifth fiscal year following current fiscal year.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920

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