Note 11 - Related Party Transactions (Details) - Ramaco Coal, LLC - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Royalties paid	$ 1.1	$ 1.2
Accounts Payable and Accrued Liabilities \| Mineral Lease and Surface Rights Agreements
Due to Related Parties, Total	$ 0.5		$ 0.4

Carrying amount as of the balance sheet date of obligations due all related parties.

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