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Related Party Disclosures (Hagarty) (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2024 | Sep. 30, 2023 | Sep. 30, 2024 | Sep. 30, 2023
Related Party Transaction [Line Items] |  |  |  |
Premiums ceded | $ 1,489,573 | $ 1,651,001 | $ 5,631,286 | $ 4,449,727
Hagerty, Inc. [Member] |  |  |  |
Related Party Transaction [Line Items] |  |  |  |
Gross premium volume | 253,071 | 227,693 | 726,995 | 628,889
Premiums ceded | $ 193,844 | $ 174,455 | $ 557,581 | $ 480,924

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