Investments - Schedule of Carrying Value and Unfunded Investment Commitments of Other Invested Assets Portfolio (Details) - USD ($) $ in Millions |
Mar. 31, 2025 |
Dec. 31, 2024 |
|---|---|---|
| Schedule of Investments [Line Items] | ||
| Carrying Value | $ 4,110.7 | $ 4,094.8 |
| Unfunded Commitments | 217.4 | 220.9 |
| Hedge funds | ||
| Schedule of Investments [Line Items] | ||
| Carrying Value | 27.0 | 27.5 |
| Unfunded Commitments | 0.0 | 0.0 |
| Private equity | ||
| Schedule of Investments [Line Items] | ||
| Carrying Value | 258.0 | 262.4 |
| Unfunded Commitments | 211.9 | 214.1 |
| Real estate equity investments | ||
| Schedule of Investments [Line Items] | ||
| Carrying Value | 283.4 | 282.6 |
| Unfunded Commitments | 5.5 | 0.0 |
| Other | ||
| Schedule of Investments [Line Items] | ||
| Carrying Value | 5.0 | 4.9 |
| Unfunded Commitments | 0.0 | 6.8 |
| Other Investments | ||
| Schedule of Investments [Line Items] | ||
| Carrying Value | $ 573.4 | $ 577.4 |
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- Definition The amount of unfunded commitments for which the entity is obligated, to those certain investments for which net asset value per share is calculated (including by unit, membership interest, or other equity (ownership interest) unit measure) (alternative investments). Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Sum of the carrying amounts as of the balance sheet date of all investments. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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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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