Related Party Disclosures (Hagerty) (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025
Related Party Transaction [Line Items]
Premiums ceded	$ 1,750,297	$ 1,620,697	$ 6,138,791	$ 6,429,776
Hagerty, Inc. [Member]
Related Party Transaction [Line Items]
Gross premiums volume	319,988	284,630	918,125	808,663
Premiums ceded	$ 308,242	$ 219,309	$ 880,483	$ 623,453

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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+ Details