Document and Entity Information	Jan. 30, 2023
Document and Entity Information [Abstract]
Document Type	8-K
Document Period End Date	Jan. 30, 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	c/o Deutsche Bank Trust Company Americas
Entity Address, Adress Line Two	Trust & Agency Services
Entity Address, Address Line Three	1 Columbus Circle, 17th Floor 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

Boolean flag that is true when the XBRL content amends previously-filed or accepted submission.

No definition available.

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- Definition

Area code of city

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No definition available.

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- Definition

For the EDGAR submission types of Form 8-K: the date of the report, the date of the earliest event reported; for the EDGAR submission types of Form N-1A: the filing date; for all other submission types: the end of the reporting or transition period. The format of the date is YYYY-MM-DD.

+ References

No definition available.

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- Definition

The type of document being provided (such as 10-K, 10-Q, 485BPOS, etc). The document type is limited to the same value as the supporting SEC submission type, or the word 'Other'.

+ References

No definition available.

+ Details

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- Definition

Address Line 1 such as Attn, Building Name, Street Name

+ References

No definition available.

+ Details

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- Definition

Address Line 2 such as Street or Suite number

+ References

No definition available.

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Data Type:	xbrli:normalizedStringItemType
Balance Type:	na
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- Definition

Address Line 3 such as an Office Park

+ References

No definition available.

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Data Type:	xbrli:normalizedStringItemType
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- Definition

Name of the City or Town

+ References

No definition available.

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Data Type:	xbrli:normalizedStringItemType
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- Definition

Code for the postal or zip code

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No definition available.

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Balance Type:	na
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- Definition

Name of the state or province.

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No definition available.

+ Details

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Namespace Prefix:	dei_
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- Definition

A unique 10-digit SEC-issued value to identify entities that have filed disclosures with the SEC. It is commonly abbreviated as CIK.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Exchange Act
-Number 240
-Section 12
-Subsection b-2

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- Definition

Indicate if registrant meets the emerging growth company criteria.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Exchange Act
-Number 240
-Section 12
-Subsection b-2

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- Definition

Commission file number. The field allows up to 17 characters. The prefix may contain 1-3 digits, the sequence number may contain 1-8 digits, the optional suffix may contain 1-4 characters, and the fields are separated with a hyphen.

+ References

No definition available.

+ Details

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- Definition

Two-character EDGAR code representing the state or country of incorporation.

+ References

No definition available.

+ Details

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Balance Type:	na
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- Definition

The exact name of the entity filing the report as specified in its charter, which is required by forms filed with the SEC.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Exchange Act
-Number 240
-Section 12
-Subsection b-2

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- Definition

The Tax Identification Number (TIN), also known as an Employer Identification Number (EIN), is a unique 9-digit value assigned by the IRS.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Exchange Act
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Data Type:	dei:employerIdItemType
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- Definition

Local phone number for entity.

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No definition available.

+ Details

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Data Type:	xbrli:normalizedStringItemType
Balance Type:	na
Period Type:	duration

- Definition

Boolean flag that is true when the Form 8-K filing is intended to satisfy the filing obligation of the registrant as pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Exchange Act
-Number 240
-Section 13e
-Subsection 4c

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Data Type:	xbrli:booleanItemType
Balance Type:	na
Period Type:	duration

- Definition

Boolean flag that is true when the Form 8-K filing is intended to satisfy the filing obligation of the registrant as pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Exchange Act
-Number 240
-Section 14d
-Subsection 2b

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- Definition

Title of a 12(b) registered security.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Exchange Act
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-Section 12
-Subsection b

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- Definition

Name of the Exchange on which a security is registered.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Exchange Act
-Number 240
-Section 12
-Subsection d1-1

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- Definition

Boolean flag that is true when the Form 8-K filing is intended to satisfy the filing obligation of the registrant as soliciting material pursuant to Rule 14a-12 under the Exchange Act.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Exchange Act
-Section 14a
-Number 240
-Subsection 12

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- Definition

Trading symbol of an instrument as listed on an exchange.

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No definition available.

+ Details

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Namespace Prefix:	dei_
Data Type:	dei:tradingSymbolItemType
Balance Type:	na
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- Definition

Boolean flag that is true when the Form 8-K filing is intended to satisfy the filing obligation of the registrant as written communications pursuant to Rule 425 under the Securities Act.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Securities Act
-Number 230
-Section 425

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- References

No definition available.

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