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Third-Party Reinsurance - Narrative (Details) - Third Point Re - P&C Insurance and Reinsurance (Ark/WM Outrigger) - USD ($) $ in Millions | Sep. 30, 2024 | Dec. 31, 2023
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Segment Reporting Information [Line Items] |  |
Annual crediting rate | 3.00% |
Carrying value of investment | $ 20.3 | $ 20.4

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