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-Topic 320
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Investments - Consolidated Investments (Details) - USD ($) $ in Millions	Sep. 30, 2024	Jun. 30, 2024	Dec. 31, 2023	Sep. 30, 2023	Jun. 30, 2023	Dec. 31, 2022
Available-for-sale securities
Amortized Cost	$ 49,026		$ 43,601
Allowance for Expected Credit Losses	(62)	$ (58)	(35)	$ (38)	$ (32)	$ (31)
Gross Unrealized Gains	797		444
Gross Unrealized Losses	(2,852)		(3,591)
Fair Value	46,909		40,419
Asset-backed securities
Available-for-sale securities
Amortized Cost	15,979		14,623
Allowance for Expected Credit Losses	(12)	(11)	(11)	(18)	(7)	(8)
Gross Unrealized Gains	264		191
Gross Unrealized Losses	(275)		(469)
Fair Value	15,956		14,334
Commercial mortgage-backed securities
Available-for-sale securities
Amortized Cost	5,304		4,732
Allowance for Expected Credit Losses	(49)	(46)	(22)	(17)	(18)	(1)
Gross Unrealized Gains	60		23
Gross Unrealized Losses	(191)		(323)
Fair Value	5,124		4,410
Corporates
Available-for-sale securities
Amortized Cost	22,302		18,780
Allowance for Expected Credit Losses	0		0	0		(15)
Gross Unrealized Gains	381		178
Gross Unrealized Losses	(2,072)		(2,379)
Fair Value	20,611		16,579
Hybrids
Available-for-sale securities
Amortized Cost	609		668
Allowance for Expected Credit Losses	0		0
Gross Unrealized Gains	6		3
Gross Unrealized Losses	(19)		(53)
Fair Value	596		618
Municipals
Available-for-sale securities
Amortized Cost	1,635		1,776
Allowance for Expected Credit Losses	0		0
Gross Unrealized Gains	20		14
Gross Unrealized Losses	(182)		(223)
Fair Value	1,473		1,567
Residential mortgage-backed securities
Available-for-sale securities
Amortized Cost	2,608		2,501
Allowance for Expected Credit Losses	(1)	$ (1)	(2)	$ (3)	$ (7)	$ (7)
Gross Unrealized Gains	61		29
Gross Unrealized Losses	(77)		(104)
Fair Value	2,591		2,424
U.S. Government
Available-for-sale securities
Amortized Cost	352		258
Allowance for Expected Credit Losses	0		0
Gross Unrealized Gains	2		4
Gross Unrealized Losses	(2)		(1)
Fair Value	352		261
Foreign Governments
Available-for-sale securities
Amortized Cost	237		263
Allowance for Expected Credit Losses	0		0
Gross Unrealized Gains	3		2
Gross Unrealized Losses	(34)		(39)
Fair Value	$ 206		$ 226