LIABILITIES FOR FUTURE POLICYHOLDER BENEFITS - Policyholder Account Balance (Details) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Dec. 31, 2023	Dec. 31, 2022
Liability for Future Policy Benefit, Expected Future Policy Benefit [Roll Forward]
Net liability for future policy benefits	$ 16,474		$ 16,573
Term
Liability for Future Policy Benefit, Expected Future Policy Benefit [Roll Forward]
Net liability for future policy benefits	1,291		1,341
Payout - Non-Legacy
Liability for Future Policy Benefit, Expected Future Policy Benefit [Roll Forward]
Net liability for future policy benefits	802		844
Payout - Legacy
Liability for Future Policy Benefit, Expected Future Policy Benefit [Roll Forward]
Net liability for future policy benefits	3,900		3,620
Group Pension
Liability for Future Policy Benefit, Expected Future Policy Benefit [Roll Forward]
Net liability for future policy benefits	457		490
Health
Liability for Future Policy Benefit, Expected Future Policy Benefit [Roll Forward]
Net liability for future policy benefits	1,414		1,505
Operating Segments | Term | Protection Solutions
Liability for Future Policy Benefit, Expected Net Premium [Roll Forward]
Balance, beginning of period	2,125	$ 2,090
Beginning balance at original discount rate	2,051	2,069
Effect of changes in cash flow assumptions			(18)	$ 8
Effect of actual variances from expected experience			(52)	4
Adjusted beginning of period balance			1,981	2,081
Issuances	26	32
Interest accrual	49	50
Net premiums collected	(94)	(99)
Ending Balance at original discount rate	1,962	2,064
Effect of changes in discount rate assumptions	(21)	35
Balance, end of period	1,941	2,099
Liability for Future Policy Benefit, Expected Future Policy Benefit [Roll Forward]
Balance, beginning of period	3,466	3,449
Beginning balance of original discount rate	3,317	3,376
Effect of changes in cash flow assumptions			(20)	9
Effect of actual variances from expected			(65)	6
Adjusted beginning of period balance			3,232	3,391
Issuances	28	34
Interest accrual	82	84
Benefits payments	(115)	(182)
Ending balance at original discount rate	3,227	3,327
Effect of changes in discount rate assumptions	5	90
Balance, end of period	3,232	3,417
Net liability for future policy benefits	1,291	1,318
Less: Reinsurance recoverable	(207)	(199)
Net liability for future policy benefits, after reinsurance recoverable	$ 1,084	$ 1,119
Weighted-average duration of liability for future policyholder benefits (years)	6 years 10 months 24 days	7 years
Operating Segments | Payout - Non-Legacy | Non-Legacy
Liability for Future Policy Benefit, Expected Net Premium [Roll Forward]
Balance, beginning of period	$ 0	$ 0
Beginning balance at original discount rate	0	0
Effect of changes in cash flow assumptions			0	0
Effect of actual variances from expected experience			0	0
Adjusted beginning of period balance			0	0
Issuances	0	0
Interest accrual	0	0
Net premiums collected	0	0
Ending Balance at original discount rate	0	0
Effect of changes in discount rate assumptions	0	0
Balance, end of period	0	0
Liability for Future Policy Benefit, Expected Future Policy Benefit [Roll Forward]
Balance, beginning of period	844	828
Beginning balance of original discount rate	840	845
Effect of changes in cash flow assumptions			0	0
Effect of actual variances from expected			(2)	0
Adjusted beginning of period balance			838	845
Issuances	22	26
Interest accrual	20	19
Benefits payments	(47)	(46)
Ending balance at original discount rate	833	844
Effect of changes in discount rate assumptions	(31)	(10)
Balance, end of period	802	834
Net liability for future policy benefits	802	834
Less: Reinsurance recoverable	(44)	(9)
Net liability for future policy benefits, after reinsurance recoverable	$ 758	$ 825
Weighted-average duration of liability for future policyholder benefits (years)	9 years 3 months 18 days	9 years 4 months 24 days
Operating Segments | Payout - Legacy | Legacy
Liability for Future Policy Benefit, Expected Net Premium [Roll Forward]
Balance, beginning of period	$ 0	$ 0
Beginning balance at original discount rate	0	0
Effect of changes in cash flow assumptions			0	0
Effect of actual variances from expected experience			0	0
Adjusted beginning of period balance			0	0
Issuances	0	0
Interest accrual	0	0
Net premiums collected	0	0
Ending Balance at original discount rate	0	0
Effect of changes in discount rate assumptions	0	0
Balance, end of period	0	0
Liability for Future Policy Benefit, Expected Future Policy Benefit [Roll Forward]
Balance, beginning of period	3,620	2,689
Beginning balance of original discount rate	3,840	3,024
Effect of changes in cash flow assumptions			0	0
Effect of actual variances from expected			0	0
Adjusted beginning of period balance			3,840	3,024
Issuances	500	474
Interest accrual	69	44
Benefits payments	(181)	(132)
Ending balance at original discount rate	4,228	3,410
Effect of changes in discount rate assumptions	(328)	(309)
Balance, end of period	3,900	3,101
Net liability for future policy benefits	3,900	3,101
Less: Reinsurance recoverable	(1,698)	(797)
Net liability for future policy benefits, after reinsurance recoverable	$ 2,202	$ 2,304
Weighted-average duration of liability for future policyholder benefits (years)	7 years 6 months	7 years 9 months 18 days
Corporate and Other | Group Pension
Liability for Future Policy Benefit, Expected Net Premium [Roll Forward]
Balance, beginning of period	$ 0	$ 0
Beginning balance at original discount rate	0	0
Effect of changes in cash flow assumptions			0	0
Effect of actual variances from expected experience			0	0
Adjusted beginning of period balance			0	0
Issuances	0	0
Interest accrual	0	0
Net premiums collected	0	0
Ending Balance at original discount rate	0	0
Effect of changes in discount rate assumptions	0	0
Balance, end of period	0	0
Liability for Future Policy Benefit, Expected Future Policy Benefit [Roll Forward]
Balance, beginning of period	490	523
Beginning balance of original discount rate	536	583
Effect of changes in cash flow assumptions			0	0
Effect of actual variances from expected			1	0
Adjusted beginning of period balance			537	583
Issuances	0	0
Interest accrual	9	10
Benefits payments	(31)	(34)
Ending balance at original discount rate	515	559
Effect of changes in discount rate assumptions	(58)	(56)
Balance, end of period	457	503
Net liability for future policy benefits	457	503
Less: Reinsurance recoverable	0	0
Net liability for future policy benefits, after reinsurance recoverable	$ 457	$ 503
Weighted-average duration of liability for future policyholder benefits (years)	7 years	7 years 1 month 6 days
Corporate and Other | Health
Liability for Future Policy Benefit, Expected Net Premium [Roll Forward]
Balance, beginning of period	$ (21)	$ (6)
Beginning balance at original discount rate	(22)	(6)
Effect of changes in cash flow assumptions			(3)	0
Effect of actual variances from expected experience			1	(6)
Adjusted beginning of period balance			(24)	(12)
Issuances	0	0
Interest accrual	0	0
Net premiums collected	2	1
Ending Balance at original discount rate	(22)	(11)
Effect of changes in discount rate assumptions	1	0
Balance, end of period	(21)	(11)
Liability for Future Policy Benefit, Expected Future Policy Benefit [Roll Forward]
Balance, beginning of period	1,484	1,554
Beginning balance of original discount rate	1,672	1,795
Effect of changes in cash flow assumptions			0	(1)
Effect of actual variances from expected			6	(6)
Adjusted beginning of period balance			$ 1,678	$ 1,788
Issuances	0	0
Interest accrual	27	29
Benefits payments	(79)	(71)
Ending balance at original discount rate	1,626	1,746
Effect of changes in discount rate assumptions	(234)	(224)
Balance, end of period	1,392	1,522
Net liability for future policy benefits	1,414	1,533
Less: Reinsurance recoverable	(1,116)	(1,217)
Net liability for future policy benefits, after reinsurance recoverable	$ 298	$ 316
Weighted-average duration of liability for future policyholder benefits (years)	8 years 7 months 6 days	8 years 9 months 18 days