Note 9 - Equity - Taxes Related to Stock Awards (Details) - USD ($) shares in Millions, $ in Millions	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
EQUITY
Number of shares surrendered	0.9	0.7	0.2
Value of shares surrendered	$ 10.6	$ 7.3	$ 3.2

Amount representing value of common shares surrendered by employees during the year to pay taxes.

No definition available.

Name:	metc_CommonStockSurrenderedValueToPayTaxes
Namespace Prefix:	metc_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration