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Variable Interest Entities (Details) - USD ($) $ in Millions | Mar. 31, 2023 | Dec. 31, 2022
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Limited Partnerships and Insurance-Linked Securities Funds |  |
Variable Interest Entity [Line Items] |  |
Fair Value | $ 159.4 |
DavidShield |  |
Variable Interest Entity [Line Items] |  |
Ownership interest (as a percent) | 53.80% |
PassportCard/DavidShield |  |
Variable Interest Entity [Line Items] |  |
Ownership interest (as a percent) | 53.80% | 53.80%
Other investments | $ 149.7 |
Elementum Holdings, L.P. |  |
Variable Interest Entity [Line Items] |  |
Ownership interest (as a percent) | 26.60% | 29.70%
Other investments | $ 30.0 |

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