INVESTMENTS - Net Investment Income (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
Net Investment Income [Line Items]
Gross investment income	$ 194,641	$ 197,988	$ 409,203	$ 372,073
Investment expenses	(7,344)	(7,013)	(14,194)	(13,715)
Net investment income	187,297	190,975	395,009	358,358
Fixed maturities
Net Investment Income [Line Items]
Gross investment income	149,861	154,023	296,572	293,419
Other investments
Net Investment Income [Line Items]
Gross investment income	18,479	14,301	40,889	19,974
Equity securities
Net Investment Income [Line Items]
Gross investment income	3,155	3,057	6,363	5,819
Mortgage loans
Net Investment Income [Line Items]
Gross investment income	5,956	9,108	12,824	18,237
Cash and cash equivalents
Net Investment Income [Line Items]
Gross investment income	16,649	13,733	50,028	27,395
Short-term investments
Net Investment Income [Line Items]
Gross investment income	$ 541	$ 3,766	$ 2,527	$ 7,229

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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