SEGMENT INFORMATION - General (Details)	12 Months Ended
Dec. 31, 2023 segment
Segment Information
Number of reportable segments	4
Number Of Coal Reportable Segments	2
Number Of Mining Complex	7
Coal Royalties
Segment Information
Coal sold by coal operations (in percent)	60.00%

Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 18
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-18

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration