Summary of Accounting Policies and Accounting Changes (Details) - USD ($) $ in Millions |
Dec. 31, 2025 |
Dec. 31, 2024 |
|---|---|---|
| Accounting Policies [Abstract] | ||
| Reinsurance Recoverables, Gross | $ 25.6 | $ 24.3 |
| Accrued investment income | 87.5 | 81.9 |
| Receivables from limited liability investments or partnership investments | 0.2 | 0.3 |
| Finite-Lived Intangible Assets [Line Items] | ||
| Finite-lived intangible assets, net | 226.5 | 266.1 |
| Value of Business Acquired | ||
| Finite-Lived Intangible Assets [Line Items] | ||
| Finite-lived intangible assets, net | 10.5 | 12.1 |
| Customer Relationships | ||
| Finite-Lived Intangible Assets [Line Items] | ||
| Finite-lived intangible assets, net | 1.1 | 1.5 |
| Agent Relationships | ||
| Finite-Lived Intangible Assets [Line Items] | ||
| Finite-lived intangible assets, net | $ 32.9 | $ 37.7 |
| X | ||||||||||
- Definition Receivables From Limited Liability Investments Or Partnership Investments No definition available.
|
| X | ||||||||||
- References No definition available.
|
| X | ||||||||||
- Definition Interest, dividends, rents, ancillary and other revenues earned but not yet received by the entity on its investments. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
|
| X | ||||||||||
- 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. Reference 1: http://www.xbrl.org/2003/role/exampleRef
|
| X | ||||||||||
- Definition Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
|
| X | ||||||||||
- Definition Amount before valuation allowance recoverable under reinsurance contracts. Examples include, but are not limited to, settled and unsettled claims, incurred but not reported losses, loss adjustment expense, premium paid, policy benefits and policy reserves. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
|
| X | ||||||||||
- Details
|
| X | ||||||||||
- Details
|
| X | ||||||||||
- Details
|