Note 9 - Income Taxes - (Details)	3 Months Ended	6 Months Ended
Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
Income Taxes.
Percentage of discrete benefit	12.70%	26.30%	23.50%	24.50%

Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to discrete items.

No definition available.

Name:	metc_EffectiveIncomeTaxRateReconciliationDiscreteExpenseBenefitPercent
Namespace Prefix:	metc_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration