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Related Party Disclosures (Hagarty) (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2025 | Sep. 30, 2024
Related Party Transaction [Line Items] |  |  |  |
Premiums ceded | $ 1,620,697 | $ 1,489,573 | $ 6,429,776 | $ 5,631,286
Hagerty, Inc. [Member] |  |  |  |
Related Party Transaction [Line Items] |  |  |  |
Gross premium volume | 284,630 | 253,071 | 808,663 | 726,995
Premiums ceded | $ 219,309 | $ 193,844 | $ 623,453 | $ 557,581

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