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Hagerty Related Party Disclosures (Details) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
Related Party Transaction [Line Items] |  |  |
Gross written premiums | $ 14,002,237 | $ 13,201,682 | $ 11,438,682
Ceded written premium | 5,604,662 | 4,998,292 | 4,318,951
Hagerty [Member] |  |  |
Related Party Transaction [Line Items] |  |  |
Gross written premiums | 805,673 | 689,670 | 596,904
Ceded written premium | $ 616,491 | $ 456,637 | $ 338,850

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