INVESTMENTS - Narrative (Details) $ in Millions	3 Months Ended	6 Months Ended	12 Months Ended
Jun. 30, 2023 USD ($) security	Sep. 30, 2022 USD ($)	Jun. 30, 2023 USD ($)	Dec. 31, 2022 USD ($) security
Debt Securities, Available-for-Sale [Line Items]
Reclassification of specific investments from fixed maturity securities, available for sale at fair value to fixed maturity securities, held to maturity at amortized cost net of credit allowances		$ 722
Unrealized loss from transfer	$ (762)		$ (762)	$ (848)
Fair value of investments in unrealized loss position	11,499		11,499	11,222
Gross unrealized losses on investments in unrealized loss position	919		919	1,013
Fixed maturity securities, duration of unrealized loss, less than 12 months, gross unrealized depreciation	127		127	591
Fixed maturity securities, duration of unrealized loss, greater than 12 months, gross unrealized depreciation	792		792	421
Additional contractual commitments	925		925
Cash surrender value of life insurance	968		968	939
Fair Value	$ 14,202		14,202	$ 12,671
Number of securities held as primary beneficiary \| security	0			0
Variable Interest Entity, Not Primary Beneficiary
Debt Securities, Available-for-Sale [Line Items]
Maximum exposure to loss	$ 2,900		2,900	$ 2,800
Commitments to fund investments	871		$ 871
Investments, Debt Securities Benchmark \| Issuer Concentration Risk \| Issuer One
Debt Securities, Available-for-Sale [Line Items]
Percentage of overall fair value of fixed maturity securities available for sale, less than			3.10%	4.30%
Investments, Debt Securities Benchmark \| Issuer Concentration Risk \| Issuer Two
Debt Securities, Available-for-Sale [Line Items]
Percentage of overall fair value of fixed maturity securities available for sale, less than			1.90%	0.60%
Investment Grade
Debt Securities, Available-for-Sale [Line Items]
Fixed maturity securities, duration of unrealized loss, less than 12 months, gross unrealized depreciation	98		$ 98	$ 520
Fixed maturity securities, duration of unrealized loss, greater than 12 months, gross unrealized depreciation	738		738	392
Fixed maturities
Debt Securities, Available-for-Sale [Line Items]
Fixed maturity securities, duration of unrealized loss, less than 12 months, gross unrealized depreciation				591
Fixed maturity securities, duration of unrealized loss, greater than 12 months, gross unrealized depreciation	792		792	421
Fair Value	1,800		1,800	$ 1,700
Private Placement Liquidity Sweep
Debt Securities, Available-for-Sale [Line Items]
Fair Value	449		449
Debt Securities, Held To Maturity
Debt Securities, Available-for-Sale [Line Items]
Unrealized loss from transfer	$ 46		$ 46

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