Note 4 - Miscellaneous Other Income - Miscellaneous Other Income (Loss) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Sale of Certain Mining Rights	$ 21,756	$ 39,437	$ 0
Royalty Income - Non-Operated Coal	8,661	12,032	22,208
Interest Income	3,287	1,230	2,937
Rental Income	1,095	1,314	2,517
Purchased Coal Sales	0	0	12,385
Contract Buyout	0	44,703	9,959
Sale of Certain Coal Lease Contracts	0	17,847	0
Other	3,595	10,323	3,343
Miscellaneous Other Income	$ 38,394	$ 126,886	$ 53,349

The amount of gain (loss) on sale of mining rights.

No definition available.

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- Definition

The amount of income (loss) from the sale of contracts.

+ References

No definition available.

+ Details

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- Definition

Represents information related to purchase coal sales.

+ References

No definition available.

+ Details

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- Definition

Represents information related to royalty income no-operated coal.

+ References

No definition available.

+ Details

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- Definition

Gain (loss) related to the termination of a contract between the parties. The termination may be due to many causes including early termination of a lease by a lessee, a breach of contract by one party, or a failure to perform.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3602-108585

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- Definition

Amount of interest income earned from interest bearing assets classified as other.

+ References

No definition available.

+ Details

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- Definition

The aggregate amount of income or expense from ancillary business-related activities (that is to say, excluding major activities considered part of the normal operations of the business).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.7)
-URI http://asc.fasb.org/extlink&oid=123367319&loc=SL114868664-224227

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- Definition

Amount of income related to nonoperating activities, classified as other.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(7)(d))
-URI http://asc.fasb.org/extlink&oid=123367319&loc=SL114868664-224227

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- Definition

Income earned by providing the use of assets to an outside party in exchange for a payment or series of payments that is nonoperating in nature.

+ References

+ Details

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