INVESTMENTS - Summary of Fixed Maturity Securities (Details) - USD ($) $ in Millions	Mar. 31, 2023	Dec. 31, 2022	Mar. 31, 2022	Dec. 31, 2021
Fixed maturity securities - available for sale
Amortized Cost	$ 25,247	$ 24,191
Allowance for Credit Losses	(62)	(54)	$ (42)	$ (30)
Unrealized Appreciation	91	81
Unrealized Depreciation	(1,716)	(1,982)
Fair Value	23,560	22,236
Fixed maturity securities - held to maturity
Amortized Cost	834	848
Allowance for Credit Losses	(9)	(9)
Unrealized Appreciation	4	3
Unrealized Depreciation	(15)	(22)
Fair Value	814	821
U.S. Treasury securities and obligations of U.S. government agencies and corporations
Fixed maturity securities - available for sale
Amortized Cost	1,323	1,334
Allowance for Credit Losses	0	0
Unrealized Appreciation	5	6
Unrealized Depreciation	(69)	(82)
Fair Value	1,259	1,257
Obligations of U.S. states and political subdivisions
Fixed maturity securities - available for sale
Amortized Cost	424	444
Allowance for Credit Losses	0	0
Unrealized Appreciation	2	2
Unrealized Depreciation	(30)	(32)
Fair Value	396	413
Corporate securities
Fixed maturity securities - available for sale
Amortized Cost	7,202	7,044
Allowance for Credit Losses	(55)	(45)	(20)	(19)
Unrealized Appreciation	29	31
Unrealized Depreciation	(497)	(561)
Fair Value	6,679	6,469
Fixed maturity securities - held to maturity
Amortized Cost	152	152
Allowance for Credit Losses	(2)	(2)
Unrealized Appreciation	1	0
Unrealized Depreciation	(3)	(6)
Fair Value	148	144
Asset-backed securities
Fixed maturity securities - available for sale
Amortized Cost	4,567	4,229
Allowance for Credit Losses	0	0	(8)	(8)
Unrealized Appreciation	5	5
Unrealized Depreciation	(129)	(171)
Fair Value	4,443	4,063
Fixed maturity securities - held to maturity
Amortized Cost	640	661
Allowance for Credit Losses	(6)	(6)
Unrealized Appreciation	1	2
Unrealized Depreciation	(12)	(15)
Fair Value	624	642
Commercial
Fixed maturity securities - available for sale
Amortized Cost	1,075	1,023
Allowance for Credit Losses	0	0
Unrealized Appreciation	1	0
Unrealized Depreciation	(102)	(105)
Fair Value	974	919
Fixed maturity securities - held to maturity
Amortized Cost	14	7
Allowance for Credit Losses	0	0
Unrealized Appreciation	0	0
Unrealized Depreciation	0	0
Fair Value	14	7
Agency residential
Fixed maturity securities - available for sale
Amortized Cost	3,690	3,382
Allowance for Credit Losses	0	0
Unrealized Appreciation	19	7
Unrealized Depreciation	(244)	(290)
Fair Value	3,465	3,099
Non-agency residential
Fixed maturity securities - available for sale
Amortized Cost	5	5
Allowance for Credit Losses	0	0
Unrealized Appreciation	0	0
Unrealized Depreciation	(1)	(1)
Fair Value	4	4
Foreign government securities
Fixed maturity securities - available for sale
Amortized Cost	1,616	1,586
Allowance for Credit Losses	0	0
Unrealized Appreciation	8	8
Unrealized Depreciation	(153)	(179)
Fair Value	1,471	1,415
Foreign corporate securities
Fixed maturity securities - available for sale
Amortized Cost	5,345	5,143
Allowance for Credit Losses	(7)	(10)	$ (14)	$ (3)
Unrealized Appreciation	22	23
Unrealized Depreciation	(491)	(562)
Fair Value	4,869	4,596
Fixed maturity securities - held to maturity
Amortized Cost	28	28
Allowance for Credit Losses	(1)	(1)
Unrealized Appreciation	2	2
Unrealized Depreciation	0	0
Fair Value	$ 29	$ 28

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) 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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