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.

No definition available.

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- Definition

The charge against earnings in the period for the uninsured portion of a loss from a fire, explosion, or natural disaster (hurricane, earthquake).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(9))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483621/220-10-S99-2

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- Definition

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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LOSS AND LOSS ADJUSTMENT EXPENSE RESERVES - Narrative (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
CAT event losses	$ 0	$ 12,147	$ 27,016	$ 29,869
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
CAT event losses	0	7,500	27,016	17,500
Prior years	855	(5,315)	4,810	(3,782)
Operating Segments \| Innovations
Liability for Claims and Claims Adjustment Expense
CAT event losses	0	0	0	0
Prior years	$ (648)	$ 94	1,316	(1,548)
Operating Segments \| Reinsurance Contract [Axis]: Adverse Reserve Development \| Open Market
Liability for Claims and Claims Adjustment Expense
Prior years			46,400	4,500
Operating Segments \| Reinsurance Contract [Axis]: Adverse Reserve Development \| Innovations
Liability for Claims and Claims Adjustment Expense
Prior years			2,600	(600)
Operating Segments \| Reinsurance Contract [Axis]: Favorable Reserve Development \| Open Market
Liability for Claims and Claims Adjustment Expense
Prior years			(41,600)	(8,300)
Operating Segments \| Reinsurance Contract [Axis]: Favorable Reserve Development \| Innovations
Liability for Claims and Claims Adjustment Expense
Prior years			$ (1,300)	$ 2,200