Note 12 - Subsequent Events (Details) - Ramaco Coal, LLC $ in Millions	Apr. 29, 2022 USD ($)
Subsequent Events
Voting interest acquired	100.00%
Initial payment due at closing	$ 10
Amount of Quarterly Installments	5
Consideration to be paid	15
Deferred consideration	55
Forecast
Subsequent Events
Amount of Quarterly Installments	10
Consideration to be paid	$ 40

Percentage of voting equity interests acquired at the acquisition date in the business combination.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463

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Period Type:	instant