Fair Value Measurements - Schedule of Other Financial Assets and Liabilities Not Carried at Fair Value (Details) - Level 2 - USD ($) $ in Millions |
Jun. 30, 2026 |
Dec. 31, 2025 |
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| Carrying Value | ||
| Fair Value, Balance Sheet Grouping, Financial Statement Captions | ||
| Senior notes | $ 1,172.2 | $ 1,172.0 |
| Junior subordinated notes | 1,216.1 | 1,216.1 |
| Fair Value | ||
| Fair Value, Balance Sheet Grouping, Financial Statement Captions | ||
| Senior notes | 1,153.9 | 1,171.0 |
| Junior subordinated notes | $ 943.3 | $ 995.2 |
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- 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
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- Definition Fair value of subordinated debt obligations including, but not limited to, subordinated loan, subordinated bond, subordinated debenture or junior debt. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Fair value portion of notes payable. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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