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Related Party Disclosures (Hagarty) (Details) - USD ($) $ in Thousands | 3 Months Ended
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Mar. 31, 2025 | Mar. 31, 2024
Related Party Transaction [Line Items] |  |
Premiums ceded | $ 1,907,939 | $ 1,708,362
Hagerty, Inc. [Member] |  |
Related Party Transaction [Line Items] |  |
Gross premium volume | 219,927 | 198,282
Premiums ceded | $ 169,685 | $ 152,685

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