Debt Additional Information

No definition available.

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- Definition

Line of Credit Facility, Additional Borrowing Capacity If Requested

+ References

No definition available.

+ Details

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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

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

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Balance Type:	credit
Period Type:	instant

- 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.

+ References

No definition available.

+ Details

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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.

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Balance Type:	credit
Period Type:	duration

- Definition

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

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Balance Type:	credit
Period Type:	instant

- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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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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- 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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- 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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- 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 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).

+ References

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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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- Definition

The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.

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Debt - Additional Information (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 1998
Debt Additional Information
Repayments of Principal in 2028	$ 354.3
Repayments of Principal in 2029	400.0
Repayments of Principal Thereafter	3,179.2
Repayments of Long-term Debt	$ 0.0	$ 350.0	$ 0.0
Unum Group Percentage Ownership of Provident Financing Trust	100.00%
Line of Credit Facility, Maximum Borrowing Capacity	$ 500.0
Interest Paid, Including Capitalized Interest, Operating and Investing Activities	201.1	190.4	183.6
Parent Company
Debt Additional Information
Repayments of Long-term Debt	0.0	350.0	$ 0.0
Five-year Unsecured Revolving Credit Facility
Debt Additional Information
Letters of Credit Outstanding	1.3
Line of Credit Facility, Additional Borrowing Capacity If Requested	200.0
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%
Revolving Credit Facility
Debt Additional Information
Amount Outstanding on Line of Credit	$ 0.0
Notes Issued in 1998 with 2038 Maturity Date \| Junior Subordinated Debt
Debt Additional Information
Stated Interest Rate of Debt	7.405%			7.405%
Proceeds from Issuance of Senior Long-term Debt				$ 300.0
Liquidation value per capital security	$ 1,000
Junior Subordinated Notes Payable Due 2038
Debt Additional Information
Stated Interest Rate of Debt				7.405%
4.000% Notes due 2024 \| Senior Notes
Debt Additional Information
Stated Interest Rate of Debt			4.00%
Debt Instrument, Repurchased Face Amount			$ 350.0
6.000% Senior Notes due 2054 \| Senior Notes
Debt Additional Information
Stated Interest Rate of Debt	6.00%
Debt Instrument, Face Amount	$ 400.0
5.250% Senior Notes due 2035 \| Senior Notes
Debt Additional Information
Stated Interest Rate of Debt	5.25%
Debt Instrument, Face Amount	$ 300.0	$ 0.0
Notes Payable due 2025 \| Senior Notes
Debt Additional Information
Repayments of Long-term Debt	$ 275.0
Stated Interest Rate of Debt	3.875%