Investments - Schedule of Privately Held Securities Held Subject to Contractual Sale Restrictions (Details) $ in Thousands	Jun. 30, 2025 USD ($)
Debt and Equity Securities, FV-NI [Line Items]
Total equity securities subject to contractual sale restrictions	$ 11,191
Privately held common stocks
Debt and Equity Securities, FV-NI [Line Items]
Total equity securities subject to contractual sale restrictions	5,181
Privately held preferred stocks
Debt and Equity Securities, FV-NI [Line Items]
Total equity securities subject to contractual sale restrictions	$ 6,010

Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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Kestrel Group Ltd 10-Q