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LOSS AND LOSS ADJUSTMENT EXPENSE RESERVES - Schedule of Net Prior Year Reserve Development by Segment (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Liability for Claims and Claims Adjustment Expense
Prior years	$ (817)	$ 5,655	$ (8,082)	$ 943
Operating Segments
Liability for Claims and Claims Adjustment Expense
Prior years			(6,126)	5,330
Operating Segments | Open Market
Liability for Claims and Claims Adjustment Expense
Prior years	(855)	5,315	(4,810)	3,782
Operating Segments | Innovations
Liability for Claims and Claims Adjustment Expense
Prior years	648	(94)	(1,316)	1,548
Corporate
Liability for Claims and Claims Adjustment Expense
Prior years	$ (610)	$ 434	$ (1,956)	$ (4,387)

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Amount, after effects of reinsurance, of expense (reversal of expense) for claims incurred in prior reporting periods and related claims settlement costs.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 944
-SubTopic 40
-Name Accounting Standards Codification
-Section 55
-Paragraph 7
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480046/944-40-55-7

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480081/944-40-50-3

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