INVESTMENTS - Net Investment Gains (Losses) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Gross realized investment gains
Fixed maturities, short-term investments, and cash and cash equivalents	$ 77,525	$ 32,920	$ 16,671
Equity securities	32,292	16,847	7,687
Gross realized investment gains	109,817	49,767	24,358
Gross realized investment losses
Fixed maturities, short-term investments, and cash and cash equivalents	(230,774)	(158,080)	(328,493)
Equity securities	(15,251)	(639)	(406)
Mortgage loans	(7,215)	0	0
Gross realized investment losses	(253,240)	(158,719)	(328,899)
(Increase) decrease in allowance for expected credit losses, fixed maturities, available for sale	6,821	974	(11,421)
(Increase) decrease in allowance for expected credit losses, mortgage loans	(17,159)	(6,220)	0
Impairment losses	(408)	(12,757)	(12,568)
Change in fair value of investment derivatives	1,783	(1,456)	7,656
Net unrealized gains (losses) on equity securities	13,852	53,781	(135,915)
Total net investment gains (losses)	$ (138,534)	$ (74,630)	$ (456,789)

Amount of realized gain on investment in debt and equity securities.

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Debt and Equity Securities, Realized Gain [Abstract]

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Amount of realized loss on investment in debt and equity securities.

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Debt and Equity Securities, Realized Loss [Abstract]

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This item represents the net realized gains and losses on available for sale debt securities, the net realized and unrealized gains and losses on equity securities with FV recorded in net income, together with the change in fair value of investment derivatives, and expected and realized credit losses.

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No definition available.

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Amount of writeoff of allowance for credit loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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-Topic 326
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Amount, excluding accrued interest, of increase (decrease) in allowance for credit loss of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of realized gain on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of realized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of realized and unrealized gain (loss) of derivative instruments not designated or qualifying as hedging instruments.

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Amount of realized gain from sale of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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Amount of realized loss from sale of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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Amount of unrealized gain (loss) on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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Amount, excluding accrued interest, of increase (decrease) in allowance for credit loss on financing receivable. Excludes net investment in lease.

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The gains (losses) included in earnings that represent the difference between the sale price and the carrying value of loans made to finance real estate acquisitions. This element refers to the gain (loss) and not to the cash proceeds of the sale. This element is a noncash adjustment to net income when calculating net cash generated by operating activities using the indirect method.

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