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- Definition

Line of Credit Facility, Additional Borrowing Capacity If Requested

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- Definition

Debt Instrument Liquidation Amount Per Share

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- Definition

Unum Group Percentage Ownership of Provident Financing Trust

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- Definition

Face (par) amount of debt instrument at time of issuance.

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- Definition

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

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- Definition

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

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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.

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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.

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- Definition

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

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No definition available.

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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.

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No definition available.

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- Definition

Fair value of the amount outstanding under the credit facility.

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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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- 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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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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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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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 fourth 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

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, 2024	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 1998
Debt Additional Information
Repayments of Principal in 2025	$ 275.0
Repayments of Principal in 2028	354.3
Repayments of Principal in 2029	400.0
Repayments of Principal Thereafter	$ 2,879.2
Unum Group Percentage Ownership of Provident Financing Trust	100.00%
Interest Paid, Including Capitalized Interest, Operating and Investing Activities	$ 190.4	$ 183.6	$ 172.9
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
Line of Credit Facility, Fair Value of Amount Outstanding	0.0
Facility agreement for contingent issuance of senior notes \| Parent Company
Debt Additional Information
Line of Credit Facility, Maximum Borrowing Capacity	$ 400.0
Line of Credit Facility, Commitment Fee Percentage	2.225%
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
4.000% Notes due 2024 \| Senior Notes
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
6.000% Senior Notes due 2054 \| Senior Notes
Debt Additional Information
Stated Interest Rate of Debt	6.00%
Debt Instrument, Face Amount	$ 400.0
Junior Subordinated Debt \| Junior Subordinated Notes Payable Due 2038
Debt Additional Information
Stated Interest Rate of Debt				7.405%