Market Risk Benefits - Asset and Liability Position and Reconciliation (Details) - USD ($) $ in Millions |
Sep. 30, 2026 |
Dec. 31, 2025 |
Dec. 31, 2024 |
|---|---|---|---|
| Market Risk Benefits | |||
| Market risk benefit asset | $ 239.2 | $ 197.1 | |
| Market risk benefit liability | 48.9 | 66.9 | |
| Net asset (liability) | 190.3 | 130.2 | |
| Retirement and Income Solutions | Individual variable annuities | |||
| Market Risk Benefits | |||
| Market risk benefit asset | 239.2 | 197.1 | |
| Market risk benefit liability | 48.9 | 66.9 | |
| Net asset (liability) | $ 190.3 | $ 130.2 | $ 137.4 |
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- Definition Amount, before effect of reinsurance and after accumulated increase (decrease) in instrument-specific credit risk, of contract or contract feature in long-duration contract issued by insurance entity that both protects contract holder from other-than-nominal capital market risk and exposes insurance entity to other-than-nominal capital market risk. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of asset position for contract or contract feature in long-duration contract issued by insurance entity that both protects contract holder from other-than-nominal capital market risk and exposes insurance entity to other-than-nominal capital market risk. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount of liability position for contract or contract feature in long-duration contract issued by insurance entity that both protects contract holder from other-than-nominal capital market risk and exposes insurance entity to other-than-nominal capital market risk. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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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/disclosureRef
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