Note 4 - Miscellaneous Other (Loss) Income - Miscellaneous Other Income (Loss) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Interest Income	$ 811	$ 122	$ 1,669	$ 366
Royalty Income - Non-Operated Coal	673	2,893	2,274	7,397
Rental Income	245	325	460	822
Contract Buyout	0	30,144	0	40,969
Unrealized Loss on Commodity Derivative Instruments	(20,437)	0	(20,437)	(0)
Other	305	452	820	552
Miscellaneous Other (Loss) Income	$ (18,403)	$ 33,936	$ (15,214)	$ 50,106

Represents information related to royalty income no-operated coal.

No definition available.

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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.

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-Topic 230
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-Section 45
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- Definition

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

+ References

No definition available.

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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

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-Publisher FASB
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-SubTopic 10
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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
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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.

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- Definition

The net change in the difference between the fair value and the carrying value, or in the comparative fair values, of open derivatives, commodity, or energy contracts, held at each balance sheet date, that was included in earnings for the period.

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