Debt Additional Information

No definition available.

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- Definition

Line of Credit Facility, Additional Borrowing Capacity If Requested

+ References

No definition available.

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- Definition

Debt Instrument Liquidation Amount Per Share

+ References

No definition available.

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- Definition

Unum Group Percentage Ownership of Provident Financing Trust

+ References

No definition available.

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- Definition

Description of minimum financial levels (for example, tangible net worth and working capital) and achievement of certain financial ratios (for example, working capital ratio and debt service coverage ratio), and adherence to certain clauses which generally require or restrict certain actions (for example, entering into a debt arrangement with equal or greater seniority, and selling or discontinuing a certain business segment or material subsidiary) to be in compliance with the covenant clauses of the debt agreement. May also include a discussion of the adverse consequences that would result if the entity violates or fails to satisfy the covenants.

+ References

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-SubTopic 20
-Name Accounting Standards Codification
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- Definition

Face (par) amount of the original debt instrument that was repurchased.

+ References

No definition available.

+ Details

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- Definition

Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

Amount of cash paid for interest, including, but not limited to, capitalized interest and payment to settle zero-coupon bond attributable to accreted interest of debt discount and debt instrument with insignificant coupon interest rate in relation to effective interest rate of borrowing attributable to accreted interest of debt discount; classified as operating and investing activities.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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-Name Accounting Standards Codification
-Section 50
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-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482913/230-10-50-2

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- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

+ Details

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- Definition

The fee, expressed as a percentage of the line of credit facility, for the line of credit facility regardless of whether the facility has been used.

+ References

No definition available.

+ Details

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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-Name Accounting Standards Codification
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- Definition

Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing after fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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- Definition

Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
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- Definition

The cash inflow during the period from additional borrowings in aggregate debt. Includes proceeds from short-term and long-term debt.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 230
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 14
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482740/230-10-45-14

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- Definition

The cash inflow from a borrowing with the highest claim on the assets of the entity in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle, if longer).

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Debt - Additional Information (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 1998
Debt Additional Information
Repayments of Principal in 2023	$ 275.0
Repayments of Principal in 2025	350.0
Repayments of Principal in 2027	354.3
Repayments of Principal Thereafter	$ 2,479.2
Unum Group Percentage Ownership of Provident Financing Trust	100.00%
Interest Paid, Including Capitalized Interest, Operating and Investing Activities	$ 183.6	$ 172.9	$ 181.6
Five-year Unsecured Revolving Credit Facility
Debt Additional Information
Letters of Credit Outstanding	0.4
Line of Credit Facility, Maximum Borrowing Capacity	500.0
Line of Credit Facility, Additional Borrowing Capacity If Requested	200.0
Five-year Unsecured Revolving Credit Facility \| Parent Company
Debt Additional Information
Letters of Credit Outstanding	$ 0.0
Facility agreement for contingent issuance of senior notes
Debt Additional Information
Line of Credit Facility, Maximum Borrowing Capacity			$ 400.0
Facility agreement for contingent issuance of senior notes \| Parent Company
Debt Additional Information
Line of Credit Facility, Commitment Fee Percentage	2.225%
Debt Instrument, Covenant Description	2.0 billion
Notes Issued in 1998 with 2038 Maturity Date \| Junior Subordinated Debt
Debt Additional Information
Stated Interest Rate of Debt				7.405%
Proceeds from Issuance of Senior Long-term Debt				$ 300.0
Liquidation value per capital security	$ 1,000
7.405% junior subordinated debt securities due 2038
Debt Additional Information
Debt Instrument, Repurchased Face Amount		14.0
Costs Related to Early Retirement of Debt		$ 1.2
4.500% Senior Notes due 2025
Debt Additional Information
Stated Interest Rate of Debt			4.50%
Costs Related to Early Retirement of Debt			$ 67.3
4.500% Senior Notes due 2025 \| Senior Notes
Debt Additional Information
Debt Instrument, Repurchased Face Amount			500.0
4.125% Senior Notes due 2051 \| Senior Notes
Debt Additional Information
Proceeds from Issuance of Debt			$ 600.0
Stated Interest Rate of Debt			4.125%
4.000% Notes due 2024
Debt Additional Information
Stated Interest Rate of Debt		4.00%
Debt Instrument, Repurchased Face Amount		$ 350.0
Costs Related to Early Retirement of Debt		$ 3.0
Junior Subordinated Debt \| Junior Subordinated Notes Payable Due 2038
Debt Additional Information
Stated Interest Rate of Debt				7.405%