Reserve for Loss and Loss Adjustment Expenses - Schedule of Prior Year Loss Development for the AmTrust Reinsurance Segment (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Segment Reporting [Line Items]
Total AmTrust Reinsurance PPD	$ 1,931	$ (7,788)	$ 2,208	$ (7,788)
AmTrust Reinsurance
Segment Reporting [Line Items]
Total AmTrust Reinsurance PPD	2,290	(7,913)	2,841	(7,913)
AmTrust Reinsurance \| AmTrust Quota Share
Segment Reporting [Line Items]
Total AmTrust Reinsurance PPD	1,340	(4,200)	1,710	(4,200)
AmTrust Reinsurance \| LPT/ADC Agreement
Segment Reporting [Line Items]
Total AmTrust Reinsurance PPD	(57)	(3,718)	122	(3,718)
AmTrust Reinsurance \| European Hospital Liability Quota Share
Segment Reporting [Line Items]
Total AmTrust Reinsurance PPD	$ 1,007	$ 5	$ 1,009	$ 5

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