COMMITMENTS AND CONTINGENCIES - Additional Information (Details)	6 Months Ended
Sep. 30, 2022 USD ($)
COMMITMENTS AND CONTINGENCIES.
Undiscounted reclamation liability	$ 366,000
Reclamation liability settlement term	20 years
Reclamation liabilities review period	3 years

Term for review of reclamation liabilities, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

No definition available.

Name:	rmri_ReclamationLiabilitiesReviewPeriod
Namespace Prefix:	rmri_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration