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Related Party Disclosures (Hagarty) (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2025 | Jun. 30, 2024 | Jun. 30, 2025 | Jun. 30, 2024
Related Party Transaction [Line Items] |  |  |  |
Premiums ceded | $ 2,901,140 | $ 2,433,351 | $ 4,809,079 | $ 4,141,713
Hagerty, Inc. [Member] |  |  |  |
Related Party Transaction [Line Items] |  |  |  |
Gross premium volume | 304,106 | 275,642 | 524,033 | 473,924
Premiums ceded | $ 234,459 | $ 211,052 | $ 404,144 | $ 363,737

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