Represents the amount of monthly installments under a debt agreement.

No definition available.

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Namespace Prefix:	metc_
Data Type:	xbrli:monetaryItemType
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Period Type:	instant

- Definition

Number of installments.

+ References

No definition available.

+ Details

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Balance Type:	na
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- Definition

Face (par) amount of debt instrument at time of issuance.

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Description of the frequency of periodic payments (monthly, quarterly, annual).

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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Balance Type:	na
Period Type:	instant

- Definition

Amount of the required periodic payments including both interest and principal payments.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

Amount, after deduction of unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

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Period Type:	instant

- Details

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Balance Type:
Period Type:

- Details

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Note 7 - Debt - J. H. Fletcher & Co. Loan (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Sep. 30, 2022	Dec. 31, 2023	Nov. 24, 2021	Jul. 23, 2021
Debt
Long-term Debt, Total		$ 91,383
J. H. Fletcher & Co \| Equipment loans
Debt
Aggregate principal amount	$ 4,400		$ 3,900	$ 900
Interest rate				0.00%
Number Of Monthly Installments	24 months	24 months
Frequency of periodic payment	monthly	monthly
Amount of monthly installments				$ 200
Amount paid per installment	$ 195
Long-term Debt, Total		$ 1,900