v3.25.2

Document and Entity Information	Jul. 01, 2025
Entity Information
Document Type	8-K
Document Period End Date	Jul. 01, 2025
Entity Registrant Name	UNUM GROUP
Entity Incorporation, State or Country Code	DE
Entity File Number	001-11294
Entity Tax Identification Number	62-1598430
Entity Address, Address Line One	1 Fountain Square
Entity Address, City or Town	Chattanooga
Entity Address, State or Province	TN
Entity Address, Postal Zip Code	37402
City Area Code	423
Local Phone Number	294-1011
Written Communications	false
Soliciting Material	false
Pre-commencement Tender Offer	false
Pre-commencement Issuer Tender Offer	false
Entity Emerging Growth Company	false
Entity Central Index Key	0000005513
Amendment Flag	false
NEW YORK STOCK EXCHANGE, INC. \| Common Class A
Entity Information
Title of 12(b) Security	Common stock, $0.10 par value
Trading Symbol	UNM
Security Exchange Name	NYSE
NEW YORK STOCK EXCHANGE, INC. \| 6.250% Junior Subordinated Notes due 2058
Entity Information
Title of 12(b) Security	6.250% Junior Subordinated Notes due 2058
Trading Symbol	UNMA
Security Exchange Name	NYSE

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

+ References

No definition available.

+ Details

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Namespace Prefix:	dei_
Data Type:	xbrli:booleanItemType
Balance Type:	na
Period Type:	duration

- Definition

Area code of city

+ References

No definition available.

+ Details

Name:	dei_CityAreaCode
Namespace Prefix:	dei_
Data Type:	xbrli:normalizedStringItemType
Balance Type:	na
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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.

+ Details

Name:	dei_DocumentPeriodEndDate
Namespace Prefix:	dei_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- 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

Name:	dei_DocumentType
Namespace Prefix:	dei_
Data Type:	dei:submissionTypeItemType
Balance Type:	na
Period Type:	duration

- Definition

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

+ References

No definition available.

+ Details

Name:	dei_EntityAddressAddressLine1
Namespace Prefix:	dei_
Data Type:	xbrli:normalizedStringItemType
Balance Type:	na
Period Type:	duration

- Definition

Name of the City or Town

+ References

No definition available.

+ Details

Name:	dei_EntityAddressCityOrTown
Namespace Prefix:	dei_
Data Type:	xbrli:normalizedStringItemType
Balance Type:	na
Period Type:	duration

- Definition

Code for the postal or zip code

+ References

No definition available.

+ Details

Name:	dei_EntityAddressPostalZipCode
Namespace Prefix:	dei_
Data Type:	xbrli:normalizedStringItemType
Balance Type:	na
Period Type:	duration

- Definition

Name of the state or province.

+ References

No definition available.

+ Details

Name:	dei_EntityAddressStateOrProvince
Namespace Prefix:	dei_
Data Type:	dei:stateOrProvinceItemType
Balance Type:	na
Period Type:	duration

- 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

+ Details

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Namespace Prefix:	dei_
Data Type:	dei:centralIndexKeyItemType
Balance Type:	na
Period Type:	duration

- 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

+ Details

Name:	dei_EntityEmergingGrowthCompany
Namespace Prefix:	dei_
Data Type:	xbrli:booleanItemType
Balance Type:	na
Period Type:	duration

- 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

Name:	dei_EntityFileNumber
Namespace Prefix:	dei_
Data Type:	dei:fileNumberItemType
Balance Type:	na
Period Type:	duration

- Definition

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

+ References

No definition available.

+ Details

Name:	dei_EntityIncorporationStateCountryCode
Namespace Prefix:	dei_
Data Type:	dei:edgarStateCountryItemType
Balance Type:	na
Period Type:	duration

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

Name:	dei_EntityInformationLineItems
Namespace Prefix:	dei_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- 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

+ Details

Name:	dei_EntityRegistrantName
Namespace Prefix:	dei_
Data Type:	xbrli:normalizedStringItemType
Balance Type:	na
Period Type:	duration

- 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
-Number 240
-Section 12
-Subsection b-2

+ Details

Name:	dei_EntityTaxIdentificationNumber
Namespace Prefix:	dei_
Data Type:	dei:employerIdItemType
Balance Type:	na
Period Type:	duration

- Definition

Local phone number for entity.

+ References

No definition available.

+ Details

Name:	dei_LocalPhoneNumber
Namespace Prefix:	dei_
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

+ Details

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Namespace Prefix:	dei_
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

+ Details

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Namespace Prefix:	dei_
Data Type:	xbrli:booleanItemType
Balance Type:	na
Period Type:	duration

- Definition

Title of a 12(b) registered security.

+ References

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

+ Details

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Namespace Prefix:	dei_
Data Type:	dei:securityTitleItemType
Balance Type:	na
Period Type:	duration

- 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

+ Details

Name:	dei_SecurityExchangeName
Namespace Prefix:	dei_
Data Type:	dei:edgarExchangeCodeItemType
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 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
-Number 240
-Section 14a
-Subsection 12

+ Details

Name:	dei_SolicitingMaterial
Namespace Prefix:	dei_
Data Type:	xbrli:booleanItemType
Balance Type:	na
Period Type:	duration

- Definition

Trading symbol of an instrument as listed on an exchange.

+ References

No definition available.

+ Details

Name:	dei_TradingSymbol
Namespace Prefix:	dei_
Data Type:	dei:tradingSymbolItemType
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 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

+ Details

Name:	dei_WrittenCommunications
Namespace Prefix:	dei_
Data Type:	xbrli:booleanItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	dei_EntityListingsExchangeAxis=exch_XNYS
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementClassOfStockAxis=us-gaap_CommonClassAMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementClassOfStockAxis=unm_A6.250JuniorSubordinatedNotesdue2058Member
Namespace Prefix:
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Unum Group 8-K