INVESTMENTS - Net Investment Gains (Losses) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Gross realized investment gains
Fixed maturities and short-term investments	$ 32,920	$ 16,671	$ 137,729
Equity securities	16,847	7,687	5,413
Gross realized investment gains	49,767	24,358	143,142
Gross realized investment losses
Fixed maturities and short-term investments	(158,080)	(328,493)	(42,613)
Equity securities	(639)	(406)	(696)
Gross realized investment losses	(158,719)	(328,899)	(43,309)
(Increase) decrease in allowance for expected credit losses, fixed maturities, available for sale	974	(11,421)	11
(Increase) decrease in allowance for expected credit losses, mortgage loans	(6,220)	0	0
Impairment losses	(12,757)	(12,568)	(22)
Change in fair value of investment derivatives	(1,456)	7,656	4,346
Net unrealized gains (losses) on equity securities	53,781	(135,915)	30,111
Total net investment gains (losses)	$ (74,630)	$ (456,789)	$ 134,279

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).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
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-Publisher FASB
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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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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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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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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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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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