INSURANCE LIABILITIES AND ANNUITY BENEFITS - Changes in Future Policy Benefit Reserves (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Dec. 31, 2023	Dec. 31, 2022
Present value of expected future policy benefits
Future policy benefit reserves	$ 37,329		$ 37,689
Long-term care
Present value of expected net premiums
Balance, beginning of year	4,063	$ 4,059
Beginning balance at locked-in discount rate	3,745	3,958
Effect of changes in cash flow assumptions			387	$ (9)
Effect of actual variances from expected experience			(26)	(42)
Adjusted beginning of year balance			4,106	3,908
Interest accrual	155	157
Net premiums collected	(298)	(296)
Effect of foreign currency	0	0
Ending balance at locked-in discount rate	3,962	3,768
Effect of changes in discount rate assumptions	355	43
Balance, end of year	4,317	3,811
Present value of expected future policy benefits
Balance, beginning of year	30,895	28,316
Beginning balance at locked-in discount rate	27,591	27,050	27,144	27,026
Effect of changes in cash flow assumptions			389	(41)
Effect of actual variances from expected experience			24	(79)
Adjusted beginning of year balance			27,557	26,906
Interest accrual	1,112	1,091
Benefit payments	(1,079)	(947)
Effect of foreign currency	0	0
Ending balance at locked-in discount rate	27,591	27,050
Effect of changes in discount rate assumptions	3,540	562
Balance, end of year	31,131	27,612
Future policy benefit reserves	26,813	23,801	26,832
Less: Reinsurance recoverables, net of allowance for credit losses	(185)	(133)
Net future policy benefit reserves, after reinsurance recoverables	$ 26,628	$ 23,668
Weighted-average duration of liability (years)	12 years 3 months 18 days	12 years 3 months 18 days
Weighted-average interest accretion rate	5.60%	5.50%
Current discount rate	5.00%	5.80%
Gross premiums or assessments recognized during period	$ 359	$ 367
Expected future gross premiums, undiscounted	7,517	7,522
Expected future gross premiums, discounted	4,938	4,656
Expected future benefit payments, undiscounted	62,798	63,406
Expected future benefit payments, discounted	31,131	27,612
Structured settlement annuities
Present value of expected net premiums
Balance, beginning of year	0	0
Beginning balance at locked-in 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 year balance			0	0
Interest accrual	0	0
Net premiums collected	0	0
Effect of foreign currency	0	0
Ending balance at locked-in discount rate	0	0
Effect of changes in discount rate assumptions	0	0
Balance, end of year	0	0
Present value of expected future policy benefits
Balance, beginning of year	9,357	8,860
Beginning balance at locked-in discount rate	8,374	8,623	8,561	8,790
Effect of changes in cash flow assumptions			0	(16)
Effect of actual variances from expected experience			(25)	18
Adjusted beginning of year balance			8,536	8,792
Interest accrual	332	342
Benefit payments	(493)	(511)
Effect of foreign currency	0	0
Ending balance at locked-in discount rate	8,374	8,623
Effect of changes in discount rate assumptions	719	(89)
Balance, end of year	9,093	8,534
Future policy benefit reserves	9,093	8,534	9,357
Less: Reinsurance recoverables, net of allowance for credit losses	0	0
Net future policy benefit reserves, after reinsurance recoverables	$ 9,093	$ 8,534
Weighted-average duration of liability (years)	10 years 10 months 24 days	10 years 6 months
Weighted-average interest accretion rate	5.40%	5.40%
Current discount rate	4.90%	5.70%
Gross premiums or assessments recognized during period	$ 0	$ 0
Expected future gross premiums, undiscounted	0	0
Expected future gross premiums, discounted	0	0
Expected future benefit payments, undiscounted	18,769	19,480
Expected future benefit payments, discounted	9,093	8,534
Life
Present value of expected net premiums
Balance, beginning of year	4,803	4,828
Beginning balance at locked-in discount rate	4,773	5,210
Effect of changes in cash flow assumptions			(1)	(77)
Effect of actual variances from expected experience			(5)	(286)
Adjusted beginning of year balance			4,768	4,847
Interest accrual	134	148
Net premiums collected	(212)	(220)
Effect of foreign currency	(41)	11
Ending balance at locked-in discount rate	4,649	4,786
Effect of changes in discount rate assumptions	(24)	(500)
Balance, end of year	4,625	4,286
Present value of expected future policy benefits
Balance, beginning of year	5,921	5,868
Beginning balance at locked-in discount rate	5,658	5,835	5,847	6,247
Effect of changes in cash flow assumptions			24	49
Effect of actual variances from expected experience			(4)	(254)
Adjusted beginning of year balance			5,867	$ 6,042
Interest accrual	164	177
Benefit payments	(329)	(396)
Effect of foreign currency	(44)	12
Ending balance at locked-in discount rate	5,658	5,835
Effect of changes in discount rate assumptions	26	(509)
Balance, end of year	5,684	5,326
Future policy benefit reserves	1,060	1,040	$ 1,117
Less: Reinsurance recoverables, net of allowance for credit losses	(32)	(39)
Net future policy benefit reserves, after reinsurance recoverables	$ 1,028	$ 1,001
Weighted-average duration of liability (years)	5 years 7 months 6 days	5 years 3 months 18 days
Weighted-average interest accretion rate	5.10%	4.90%
Current discount rate	4.60%	5.60%
Gross premiums or assessments recognized during period	$ 241	$ 251
Expected future gross premiums, undiscounted	12,011	12,387
Expected future gross premiums, discounted	5,576	5,144
Expected future benefit payments, undiscounted	10,868	11,214
Expected future benefit payments, discounted	$ 5,684	$ 5,326