FAIR VALUE OF ASSETS AND LIABILITIES - Changes in Level 3 Assets and Liabilities (Details) - USD ($) $ in Millions	3 Months Ended				6 Months Ended	12 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2022	Mar. 31, 2022	Jun. 30, 2023	Dec. 31, 2022
Future policy benefits
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, beginning of period			$ 3,393	$ 4,060		$ 4,060
Total realized and unrealized gains (losses)				715
Purchases				0
Sales				0
Issuances				(48)
Settlements				0
Other				0
Transfers into Level 3				0
Transfers out of Level 3				0
Fair Value, end of period				3,393
Unrealized gains (losses) for liabilities still held				686
Policyholders' account balances
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, beginning of period			1,934	2,041		2,041
Total realized and unrealized gains (losses)				124
Purchases				0
Sales				0
Issuances				0
Settlements				(17)
Other				0
Transfers into Level 3				0
Transfers out of Level 3				0
Fair Value, end of period				1,934
Unrealized gains (losses) for liabilities still held				89
Insurance Liabilities
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, beginning of period			13,661
Total realized and unrealized gains (losses)					$ (562)	(8,065)
Reduction in estimates of ultimate losses			(1,654)
Increase in estimates of ultimate losses			1,206
Change in fair value (discount rate)			(1,520)
Paid losses			98
Other			(534)
Fair Value, end of period		$ 11,257	11,257	13,661
Insurance Liabilities | Retained Business
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, beginning of period	$ 3,056				2,941
Total realized and unrealized gains (losses)					(230)	(421)
Reduction in estimates of ultimate losses	(354)				(702)
Increase in estimates of ultimate losses	103				235
Change in fair value (discount rate)	(189)				46
Paid losses	96				196
Other	(1)				(5)
Fair Value, end of period	2,711				2,711	2,941
Insurance Liabilities | Ceded Business
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, beginning of period	2,695				2,605
Total realized and unrealized gains (losses)					(332)	(7,644)
Reduction in estimates of ultimate losses	(559)				(625)
Increase in estimates of ultimate losses	143				210
Change in fair value (discount rate)	(20)				56
Paid losses	14				27
Other	0				0
Fair Value, end of period	2,273				2,273	2,605
Residential mortgage loans | Retained Business
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, beginning of period	158				161
Total realized and unrealized gains (losses)	0				0
Purchases	31				44
Sales	0				0
Issuances	0				0
Settlements	(38)				(54)
Other	0				0
Transfers into Level 3	0				0
Transfers out of Level 3	0				0
Fair Value, end of period	151				151	161
Unrealized gains (losses) for assets still held	0				0
Commercial mortgage-backed securities | Retained Business
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, beginning of period	48				35
Total realized and unrealized gains (losses)	0				0
Purchases	30				43
Sales	0				0
Issuances	0				0
Settlements	0				0
Other	0				0
Transfers into Level 3	0				0
Transfers out of Level 3	0				0
Fair Value, end of period	78				78	35
Unrealized gains (losses) for assets still held	0				0
Short term investments
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, beginning of period			0	13		13
Total realized and unrealized gains (losses)				0
Purchases				0
Sales				0
Issuances				0
Settlements				(13)
Other				0
Transfers into Level 3				0
Transfers out of Level 3				0
Fair Value, end of period				0
Unrealized gains (losses) for assets still held				0
Cash equivalents
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, beginning of period			0	8		8
Total realized and unrealized gains (losses)				0
Purchases				0
Sales				0
Issuances				0
Settlements				(8)
Other				0
Transfers into Level 3				0
Transfers out of Level 3				0
Fair Value, end of period				0
Unrealized gains (losses) for assets still held				0
Other assets
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, beginning of period			376	400		400
Total realized and unrealized gains (losses)				(21)
Purchases				13
Sales				0
Issuances				0
Settlements				(16)
Other				0
Transfers into Level 3				0
Transfers out of Level 3				0
Fair Value, end of period				376
Unrealized gains (losses) for assets still held				(6)
Deposit asset
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, beginning of period	608				607
Total realized and unrealized gains (losses)	(10)				(8)
Purchases	0				0
Sales	0				0
Issuances	0				0
Settlements	0				0
Other	(122)				(123)
Transfers into Level 3	0				0
Transfers out of Level 3	0				0
Fair Value, end of period	476				476	607
Unrealized gains (losses) for assets still held	0				0
Reinsurance recoverables
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, beginning of period	247		1,866	1,881	235	1,881
Total realized and unrealized gains (losses)	(47)			201	(35)
Purchases	0			4	0
Sales	0			0	0
Issuances	0			0	0
Settlements	0			19	0
Other	0			(239)	0
Transfers into Level 3	0			0	0
Transfers out of Level 3	0			0	0
Fair Value, end of period	200			1,866	200	235
Unrealized gains (losses) for assets still held	0			222	0
Net modified coinsurance receivable (payable)
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, beginning of period	(45)				18
Total realized and unrealized gains (losses)	(36)				(99)
Purchases	0				0
Sales	0				0
Issuances	0				0
Settlements	0				0
Other	0				0
Transfers into Level 3	0				0
Transfers out of Level 3	0				0
Fair Value, end of period	(81)				(81)	18
Unrealized gains (losses) for assets still held	0				0
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, end of period	81				81
Fixed maturity securities | U.S Treasury securities and obligations of U.S. government authorities and agencies
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, beginning of period			0	0		0
Total realized and unrealized gains (losses)				0
Purchases				0
Sales				0
Issuances				0
Settlements				0
Other				0
Transfers into Level 3				0
Transfers out of Level 3				0
Fair Value, end of period				0
Unrealized gains (losses) for assets still held				0
Fixed maturity securities | Corporate Securities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, beginning of period	182	190	180	190	146	190
Total realized and unrealized gains (losses)	1	(16)		(9)	1
Purchases	27	207		5	46
Sales	0	0		(4)	0
Issuances	0	0		0	0
Settlements	0	(11)		(2)	(1)
Other	0	(3)		0	0
Transfers into Level 3	18	0		0	18
Transfers out of Level 3	(18)	(53)		0	0
Fair Value, end of period	210	314	314	180	210	146
Unrealized gains (losses) for assets still held	2		(13)	(9)	1
Fixed maturity securities | Structured securities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, beginning of period		33	47	76		76
Total realized and unrealized gains (losses)		0		(4)
Purchases		25		0
Sales		(10)		(10)
Issuances		0		0
Settlements		0		(2)
Other		(10)		0
Transfers into Level 3		0		0
Transfers out of Level 3		(13)		(13)
Fair Value, end of period		25	25	47
Unrealized gains (losses) for assets still held			0	(4)
Fixed maturity securities | Foreign corporate private securities | Retained Business
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, beginning of period	36				36
Total realized and unrealized gains (losses)	(2)				(2)
Purchases	0				0
Sales	0				0
Issuances	0				0
Settlements	0				0
Other	0				0
Transfers into Level 3	0				0
Transfers out of Level 3	0				0
Fair Value, end of period	34				34	36
Unrealized gains (losses) for assets still held	(3)				(2)
Fixed maturity securities | Foreign corporate private securities | Ceded Business
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, beginning of period	0
Total realized and unrealized gains (losses)	0
Purchases	5
Sales	0
Issuances	0
Settlements	(2)
Other	0
Transfers into Level 3	0
Transfers out of Level 3	0
Fair Value, end of period	3				3
Unrealized gains (losses) for assets still held	0
Fixed maturity securities | Asset-backed securities | Retained Business
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, beginning of period	191				155
Total realized and unrealized gains (losses)	0				(2)
Purchases	18				56
Sales	0				0
Issuances	0				0
Settlements	(1)				(1)
Other	0				0
Transfers into Level 3	0				0
Transfers out of Level 3	0				0
Fair Value, end of period	208				208	155
Unrealized gains (losses) for assets still held	$ 1				$ (1)
Fixed maturity securities | Secured receivable
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, beginning of period		1,622
Total realized and unrealized gains (losses)		(50)
Purchases		0
Sales		(15)
Issuances		0
Settlements		0
Other		(2)
Transfers into Level 3		0
Transfers out of Level 3		0
Fair Value, end of period		1,555	1,555
Unrealized gains (losses) for assets still held			0
Fixed maturity securities | Deposit asset
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, beginning of period		2,615
Total realized and unrealized gains (losses)		(457)
Purchases		0
Sales		0
Issuances		0
Settlements		0
Other		0
Transfers into Level 3		0
Transfers out of Level 3		0
Fair Value, end of period		2,158	2,158
Unrealized gains (losses) for assets still held			0
Fixed maturity securities | Reinsurance recoverables
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, beginning of period		344
Total realized and unrealized gains (losses)		34
Purchases		0
Sales		0
Issuances		0
Settlements		0
Other		0
Transfers into Level 3		0
Transfers out of Level 3		0
Fair Value, end of period		378	378
Unrealized gains (losses) for assets still held			0
Fixed maturity securities | Net modified coinsurance receivable (payable)
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, beginning of period		5
Total realized and unrealized gains (losses)		210
Purchases		0
Sales		0
Issuances		0
Settlements		0
Other		0
Transfers into Level 3		0
Transfers out of Level 3		0
Fair Value, end of period		$ 215	215
Unrealized gains (losses) for assets still held			0
Equity securities | Equity securities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, beginning of period			$ 1	1		$ 1
Total realized and unrealized gains (losses)				0
Purchases				0
Sales				0
Issuances				0
Settlements				0
Other				0
Transfers into Level 3				0
Transfers out of Level 3				0
Fair Value, end of period				1
Unrealized gains (losses) for assets still held				$ 0