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v3.25.3

Related Party Transactions (Narrative) (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2025 | Sep. 30, 2024 | Dec. 31, 2024
Related Party Transaction [Line Items] |  |  |  |  |
Services and other revenues | $ 875,608 | $ 735,872 | $ 2,340,109 | $ 2,037,991 |
Premiums ceded | 1,620,697 | 1,489,573 | 6,429,776 | 5,631,286 |
Reinsurance recoverables | 12,989,511 |  | 12,989,511 |  | $ 11,604,844
Nephila Reinsurers [Member] |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |
Reinsurance recoverables | 604,300 |  | 604,300 |  | 968,900
Hagerty, Inc. [Member] |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |
Gross premium volume | 284,630 | 253,071 | 808,663 | 726,995 |
Premiums ceded | 219,309 | 193,844 | 623,453 | 557,581 |
Reinsurance recoverables | 328,900 |  | 328,900 |  | $ 308,800
Industry Loss Warranties (ILW) Program | Nephila Reinsurers [Member] |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |
Gross premium volume | 7,000 |  | 81,500 | 168,000 |
Premiums ceded | 7,000 |  | 81,500 | 168,000 |
Fronting | Nephila Reinsurers [Member] |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |
Gross premium volume | 162,900 | 94,300 | 1,800,000 | 1,200,000 |
Premiums ceded | 162,900 | 94,300 | 1,800,000 | 1,200,000 |
Fund Management | Unconsolidated entities managed by Nephila [Member] |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |
Services and other revenues | $ 30,300 | $ 25,100 | $ 85,000 | $ 66,200 |

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