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Investments (Fixed Maturity Securities Available-For-Sale by Sector) (Details) - USD ($) $ in Millions	Sep. 30, 2025	Jun. 30, 2025	Dec. 31, 2024	Sep. 30, 2024	Jun. 30, 2024	Dec. 31, 2023
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 324,833		$ 307,421
Amortized cost of fixed maturity securities valuation allowances	(248)	$ (151)	(160)	$ (162)	$ (121)	$ (184)
Gross Unrealized Gains	7,305		4,981
Gross Unrealized Losses	27,245		31,199
Estimated Fair Value of Fixed Maturity Securities AFS	304,645		281,043
U.S. corporate
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	88,912		86,315
Amortized cost of fixed maturity securities valuation allowances	(153)	(62)	(59)	(60)	(37)	(68)
Gross Unrealized Gains	1,895		1,331
Gross Unrealized Losses	6,436		8,213
Estimated Fair Value of Fixed Maturity Securities AFS	84,218		79,374
Foreign corporate
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	61,522		58,646
Amortized cost of fixed maturity securities valuation allowances	0	0	(18)	(15)	(2)	(2)
Gross Unrealized Gains	2,448		1,478
Gross Unrealized Losses	4,547		6,347
Estimated Fair Value of Fixed Maturity Securities AFS	59,423		53,759
Foreign government
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	47,687		44,377
Amortized cost of fixed maturity securities valuation allowances	(57)	(57)	(57)	(62)	(58)	(88)
Gross Unrealized Gains	1,275		1,256
Gross Unrealized Losses	6,681		5,326
Estimated Fair Value of Fixed Maturity Securities AFS	42,224		40,250
RMBS
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	45,113		37,085
Amortized cost of fixed maturity securities valuation allowances	(2)	(2)	(1)	(1)	(1)	(1)
Gross Unrealized Gains	758		314
Gross Unrealized Losses	2,144		2,977
Estimated Fair Value of Fixed Maturity Securities AFS	43,725		34,421
U.S. government and agency
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	37,681		38,963
Amortized cost of fixed maturity securities valuation allowances	0		0
Gross Unrealized Gains	327		179
Gross Unrealized Losses	5,296		5,714
Estimated Fair Value of Fixed Maturity Securities AFS	32,712		33,428
ABS & CLO
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	21,810		20,973
Amortized cost of fixed maturity securities valuation allowances	(6)	(5)	(9)	(10)	(9)	(7)
Gross Unrealized Gains	259		153
Gross Unrealized Losses	363		526
Estimated Fair Value of Fixed Maturity Securities AFS	21,700		20,591
Municipals
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	12,032		11,205
Amortized cost of fixed maturity securities valuation allowances	0		0
Gross Unrealized Gains	216		166
Gross Unrealized Losses	1,359		1,498
Estimated Fair Value of Fixed Maturity Securities AFS	10,889		9,873
CMBS
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	10,076		9,857
Amortized cost of fixed maturity securities valuation allowances	(30)	$ (25)	(16)	$ (14)	$ (14)	$ (18)
Gross Unrealized Gains	127		104
Gross Unrealized Losses	419		598
Estimated Fair Value of Fixed Maturity Securities AFS	$ 9,754		$ 9,347