INVESTMENTS - Net Investment Income (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Net Investment Income [Line Items]
Gross investment income	$ 144,209	$ 98,606	$ 285,471	$ 197,084
Investment expenses	(7,380)	(6,392)	(14,870)	(13,515)
Net investment income	136,829	92,214	270,601	183,569
Fixed maturities
Net Investment Income [Line Items]
Gross investment income	124,390	72,607	242,652	137,416
Other investments
Net Investment Income [Line Items]
Gross investment income	(5,341)	14,327	(4,855)	40,377
Equity securities
Net Investment Income [Line Items]
Gross investment income	2,990	2,688	5,445	4,860
Mortgage loans
Net Investment Income [Line Items]
Gross investment income	8,880	4,903	17,266	9,067
Cash and cash equivalents
Net Investment Income [Line Items]
Gross investment income	11,161	3,679	21,174	4,797
Short-term investments
Net Investment Income [Line Items]
Gross investment income	$ 2,129	$ 402	$ 3,789	$ 567

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.

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-Topic 946
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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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