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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Revenue (Details) |  |  |  | 1 Months Ended | 3 Months Ended | 12 Months Ended
--- | --- | --- | --- | --- | --- | ---
Apr. 15, 2025 $ / shares | Oct. 04, 2024 USD ($) | Sep. 06, 2024 USD ($) | Jan. 31, 2025 USD ($) $ / shares | Mar. 31, 2024 item | Jan. 31, 2025 USD ($) | Jan. 31, 2024 USD ($) | Jan. 31, 2025 USD ($) contract MT $ / T shares | Jan. 31, 2024 USD ($) $ / T shares | Jan. 31, 2023 USD ($) $ / T
Disaggregation of Revenue [Line Items] |  |  |  |  |  |  |  |  |  |
Number of units outstanding | shares |  |  |  |  |  |  |  | 13,120,010 | 13,120,010 |
Cash and Cash Equivalents |  |  |  |  |  |  |  |  |  |
Amount held by the Trust in a money market fund |  |  |  | $ 100,204,531 |  | $ 100,204,531 | $ 23,980,448 | $ 100,204,531 | $ 23,980,448 |
Revenue from Contract with Customer [Abstract] |  |  |  |  |  |  |  |  |  |
Litigation settlement, damages |  | $ 71,185,029 |  |  |  |  |  | 71,185,029 |  |
Pricing adjustment |  |  |  |  |  | 0 | 279,223 |  |  |
Accrued income receivable |  |  |  | 1,160,761 |  | 1,160,761 | 1,960,358 | $ 1,160,761 | $ 1,960,358 | $ 23,562
Bonus royalty percentage |  |  |  |  |  |  |  | 0.50% |  |
Bonus royalty, gross proceeds percentage |  |  |  |  |  |  |  | 3.00% |  |
Royalty bonuses, price above adjusted threshold price per ton | $ / T |  |  |  |  |  |  |  | 2 |  |
Adjusted threshold price (in dollars per ton) | $ / T |  |  |  |  |  |  |  | 69.41 | 67.75 | 66
Number of members on panel for arbitration | item |  |  |  |  | 3 |  |  |  |  |
Litigation settlement, amount |  |  | $ 59,799,977 |  |  |  |  |  |  |
Litigation settlement, interest |  |  | $ 11,385,052 |  |  |  |  |  |  |
Litigation settlement, percentage |  |  | 10.00% |  |  |  |  |  |  |
Litigation Settlement, Gain |  | $ 71,185,029 |  |  |  |  |  | $ 71,185,029 |  |
Percentage of fee interest owned by Mesabi Land Trust in the lands subject to the Peters Lease |  |  |  |  |  |  |  | 20.00% |  |
Number of customer contracts | contract |  |  |  |  |  |  |  | 1 |  |
Net contract asset |  |  |  | 240,642 |  | 240,642 | 451,896 | $ 240,642 | $ 451,896 |
Contract asset |  |  |  | 240,642 |  | 240,642 | 451,896 | 240,642 | 451,896 | $ 0
Revenue related to contract liability |  |  |  |  |  |  |  |  | 2,298,121 |
Contract liability |  |  |  | 0 |  | 0 | 0 | 0 | 0 | 2,298,121
Net contract liability |  |  |  |  |  |  |  |  |  | $ 2,298,121
Accounts receivable, allowance for credit loss |  |  |  | $ 0 |  | $ 0 | $ 0 | $ 0 | $ 0 |
Distributions payable per unit | $ / shares |  |  |  | $ 5.95 |  |  |  |  |  |
Subsequent Event [Member] |  |  |  |  |  |  |  |  |  |
Revenue from Contract with Customer [Abstract] |  |  |  |  |  |  |  |  |  |
Distributions payable per unit | $ / shares | $ 0.56 |  |  |  |  |  |  |  |  |
Minimum |  |  |  |  |  |  |  |  |  |
Revenue from Contract with Customer [Abstract] |  |  |  |  |  |  |  |  |  |
Bonus royalty, gross proceeds percentage |  |  |  |  |  |  |  | 1.00% |  |
Maximum |  |  |  |  |  |  |  |  |  |
Revenue from Contract with Customer [Abstract] |  |  |  |  |  |  |  |  |  |
Royalty bonuses, adjusted threshold price | $ / T |  |  |  |  |  |  |  | 10 |  |
First Million Tons Shipped or Deemed Shipped [Member] |  |  |  |  |  |  |  |  |  |
Revenue from Contract with Customer [Abstract] |  |  |  |  |  |  |  |  |  |
Royalty earned on tons shipped or deemed shipped, percentage |  |  |  |  |  |  |  | 2.50% |  |
Second Million Tons Shipped or Deemed Shipped [Member] |  |  |  |  |  |  |  |  |  |
Revenue from Contract with Customer [Abstract] |  |  |  |  |  |  |  |  |  |
Royalty earned on tons shipped or deemed shipped, percentage |  |  |  |  |  |  |  | 3.50% |  |
Third Million Tons Shipped or Deemed Shipped [Member] |  |  |  |  |  |  |  |  |  |
Revenue from Contract with Customer [Abstract] |  |  |  |  |  |  |  |  |  |
Royalty earned on tons shipped or deemed shipped, percentage |  |  |  |  |  |  |  | 5.00% |  |
Fourth Million Tons Shipped or Deemed Shipped [Member |  |  |  |  |  |  |  |  |  |
Revenue from Contract with Customer [Abstract] |  |  |  |  |  |  |  |  |  |
Royalty earned on tons shipped or deemed shipped, percentage |  |  |  |  |  |  |  | 5.50% |  |
Beyond Four Million Tons Shipped or Deemed Shipped [Member] |  |  |  |  |  |  |  |  |  |
Revenue from Contract with Customer [Abstract] |  |  |  |  |  |  |  |  |  |
Royalty earned on tons shipped or deemed shipped, percentage |  |  |  |  |  |  |  | 6.00% |  |
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 |  |

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