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v3.25.2

Related Party Transactions (Narrative) (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Jun. 30, 2025 | Jun. 30, 2024 | Jun. 30, 2025 | Jun. 30, 2024 | Dec. 31, 2024
Related Party Transaction [Line Items] |  |  |  |  |
Services and other revenues | $ 803,918 | $ 684,481 | $ 1,464,501 | $ 1,302,119 |
Premiums ceded | 2,901,140 | 2,433,351 | 4,809,079 | 4,141,713 |
Reinsurance recoverables | 12,789,658 |  | 12,789,658 |  | $ 11,604,844
Nephila Reinsurers [Member] |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |
Reinsurance recoverables | 986,200 |  | 986,200 |  | 968,900
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 |
Reinsurance recoverables | 314,700 |  | 314,700 |  | $ 308,800
Industry Loss Warranties (ILW) Program | Nephila Reinsurers [Member] |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |
Gross premium volume | 60,500 | 168,000 | 74,200 | 168,000 |
Premiums ceded | 60,500 | 168,000 | 74,200 | 168,000 |
Fronting | Nephila Reinsurers [Member] |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |
Gross premium volume | 1,300,000 | 741,700 | 1,700,000 | 1,100,000 |
Premiums ceded | 1,300,000 | 741,700 | 1,700,000 | 1,100,000 |
Fund Management | Unconsolidated entities managed by Nephila [Member] |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |
Services and other revenues | $ 29,100 | $ 21,800 | $ 54,600 | $ 41,100 |

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