INVESTMENTS - Net Investment Income (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Net Investment Income [Line Items]
Gross investment income	$ 189,041	$ 194,641	$ 380,808	$ 409,203
Investment expenses	(7,447)	(7,344)	(14,475)	(14,194)
Net investment income	181,594	187,297	366,333	395,009
Fixed maturities
Net Investment Income [Line Items]
Gross investment income	163,304	149,861	320,000	296,572
Other investments
Net Investment Income [Line Items]
Gross investment income	6,226	18,479	23,931	40,889
Equity securities
Net Investment Income [Line Items]
Gross investment income	4,631	3,155	8,782	6,363
Mortgage loans
Net Investment Income [Line Items]
Gross investment income	4,154	5,956	8,319	12,824
Cash and cash equivalents
Net Investment Income [Line Items]
Gross investment income	10,655	16,649	19,573	50,028
Short-term investments
Net Investment Income [Line Items]
Gross investment income	$ 71	$ 541	$ 203	$ 2,527

The net gain or loss (both realized and unrealized) related to investments in certain entities that calculate net asset value per share and the amount after accretion (amortization) of discount (premium), of interest income and dividend income on nonoperating securities.

No definition available.

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The net gain or loss (both realized and unrealized) related to investments in certain entities that calculate net asset value per share and the amount after accretion (amortization) of discount (premium) of interest income and dividend income on nonoperating securities, net of investment expense.

+ References

No definition available.

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- Definition

Amount of expenses related to the generation of investment income.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 946
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-Name Accounting Standards Codification
-Section 55
-Paragraph 10
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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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