Document and Entity Information
| Document and Entity Information | Oct. 13, 2023 |
| Document and Entity Information [Abstract] | |
| Document Type | 8-K |
| Document Period End Date | Oct. 13, 2023 |
| Entity File Number | 1-4488 |
| Entity Registrant Name | MESABI TRUST |
| Entity Incorporation, State or Country Code | NY |
| Entity Tax Identification Number | 13-6022277 |
| Entity Address, Address Line One | 1 Columbus Circle, 17th Floor |
| Entity Address, Adress Line Two | Mail Stop: NYC01-1710 |
| Entity Address, City or Town | New York |
| Entity Address, State or Province | NY |
| Entity Address, Postal Zip Code | 10019 |
| City Area Code | 904 |
| Local Phone Number | 271-2520 |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Title of 12(b) Security | Units of Beneficial Interest, no par value |
| Trading Symbol | MSB |
| Security Exchange Name | NYSE |
| Entity Emerging Growth Company | false |
| Entity Central Index Key | 0000065172 |
| Amendment Flag | false |