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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Revenue (Details) |  | 1 Months Ended | 12 Months Ended
--- | --- | --- | ---
Oct. 29, 2021 USD ($) | Jul. 31, 2021 USD ($) item | Jan. 31, 2023 USD ($) contract item MT shares | Jan. 31, 2022 USD ($) shares | Jan. 31, 2021 shares
Disaggregation of Revenue [Line Items] |  |  |  |  |
Number of units outstanding | shares |  |  | 13,120,010 | 13,120,010 | 13,120,010
Cash and Cash Equivalents |  |  |  |  |
Amount held by the Trust in a money market fund |  |  | $ 13,966,500 | $ 47,727,522 |
Investments |  |  |  |  |
Assets Held-in-trust |  |  | 0 | 0 |
Revenue from Contract with Customer [Abstract] |  |  |  |  |
Number of members on panel for arbitration | item |  | 3 |  |  |
Litigation settlement, damages | $ 2,312,106 | $ 2,312,106 |  |  |
Litigation settlement, interest | 521,581 | $ 430,710 |  |  |
Proceeds from Legal Settlements | $ 2,833,687 |  |  |  |
Accrued income receivable |  |  | $ 23,562 | 4,631,510 |
Number of customer contracts | contract |  |  | 1 |  |
Contract asset |  |  |  | 1,431,633 |
Contract liability |  |  | $ 2,298,121 | 0 |
Contract asset |  |  | 0 | $ 1,431,633 |
Contract liability |  |  | $ 2,298,121 |  |
Fixed Property, Including Intangibles |  |  |  |  |
Percentage of fee interest owned by Mesabi Land Trust in the lands subject to the Peters Lease |  |  | 20.00% |  |
Base Overriding Royalties |  |  |  |  |
Revenue from Contract with Customer [Abstract] |  |  |  |  |
Base overriding royalties, first tier portion percentage |  |  | 90.00% |  |
Base overriding royalties, first tier shipment ceiling (in million tons) | MT |  |  | 4 |  |
Base overriding royalties, second tier portion percentage |  |  | 85.00% |  |
Base overriding royalties, second tier shipment ceiling (in million tons) | MT |  |  | 2 |  |
Base overriding royalties, third tier portion percentage |  |  | 25.00% |  |
Base overriding royalties, third tier shipment threshold (in million tons) | MT |  |  | 6 |  |
Base overriding royalties, number of volume thresholds for transaction price | item |  |  | 4 |  |
Base overriding royalties, volume threshold for transaction price | MT |  |  | 1 |  |

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- Definition Investment in short-term money-market instruments (such as commercial paper, banker's acceptances, repurchase agreements, government securities, certificates of deposit, and so forth) which are highly liquid (that is, readily convertible to known amounts of cash) and so near their maturity that they present an insignificant risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify as cash equivalents by definition. Original maturity means an original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three-years ago does not become a cash equivalent when its remaining maturity is three months. + References No definition available. + Details
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