Note 4 - Miscellaneous Other Income - Miscellaneous Other Income (Loss) (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Royalty Income - Non-Operated Coal	$ 2,821	$ 2,241	$ 5,095	$ 9,638
Interest Income	737	76	2,406	442
Rental Income	256	255	716	1,077
Contract Buyout	0	0	0	40,969
Sale of Certain Coal Lease Contracts	0	17,847	0	17,847
Other	467	582	1,287	1,134
Miscellaneous Other Income	$ 4,281	$ 21,001	$ 9,504	$ 71,107

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

No definition available.

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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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