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v3.26.1

Reinsurance (Schedule of Trust Assets and Reinsurance Liabilities) (Details) - USD ($) $ in Millions | Jun. 30, 2026 | Dec. 31, 2025 | Jun. 30, 2025 | Dec. 31, 2024
--- | --- | --- | --- | ---
Reinsurance [Line Items] |  |  |  |  |
Restricted cash and cash equivalents |  | $ 490.7 | $ 477.9 | $ 493.8 | $ 501.3
Debt Securities, Available-for-sale, Restricted |  | 116.6 | 106.2 |  |
Trust Assets [Member] |  |  |  |  |
Reinsurance [Line Items] |  |  |  |  |
Restricted cash and cash equivalents |  | 0.8 | 0.7 |  |
Debt Securities, Available-for-sale, Restricted |  | 116.6 | 106.2 |  |
Unearned Premium [Member] |  |  |  |  |
Reinsurance [Line Items] |  |  |  |  |
Accounts payable and accrued liabilities |  | 78.3 | 74.0 |  |
Claims Reserve [Member] |  |  |  |  |
Reinsurance [Line Items] |  |  |  |  |
Accounts payable and accrued liabilities | [1] | $ 5.9 | $ 5.9 |  |
[1] | The claims reserve represents our liability for incurred-but-not-reported claims and is estimated based on historical claims experience.

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