Investments - Fixed Maturities, AFS (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 17,363	$ 18,689
Allowance for Credit Losses	(16)	0	$ 0
Fair Value	15,106	15,714
Total fixed maturities, available-for-sale
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	17,335	18,689
Allowance for Credit Losses	(16)	0
Gross Unrealized Gains	38	3
Gross Unrealized Losses	(2,503)	(3,309)
Fair Value	14,854	15,383
Asset-backed securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	376	276
Allowance for Credit Losses	0	0
Gross Unrealized Gains	3	0
Gross Unrealized Losses	(16)	(22)
Fair Value	363	254
Collateralized loan obligations
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	970	703
Allowance for Credit Losses	(2)	0
Gross Unrealized Gains	3	0
Gross Unrealized Losses	(5)	(27)
Fair Value	966	676
Commercial mortgage-backed securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	1,639	1,724
Allowance for Credit Losses	(7)	0	0
Gross Unrealized Gains	0	1
Gross Unrealized Losses	(186)	(211)
Fair Value	1,446	1,514
Corporate bonds
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	11,245	12,565
Allowance for Credit Losses	(7)	0	$ 0
Gross Unrealized Gains	22	2
Gross Unrealized Losses	(1,715)	(2,326)
Fair Value	9,545	10,241
Foreign governments
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	442	377
Allowance for Credit Losses	0	0
Gross Unrealized Gains	10	0
Gross Unrealized Losses	(48)	(62)
Fair Value	404	315
Municipal bonds
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	961	1,309
Allowance for Credit Losses	0	0
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(158)	(269)
Fair Value	803	1,040
Residential mortgage-backed securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	508	503
Allowance for Credit Losses	0	0
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(63)	(86)
Fair Value	445	417
U.S. Treasury bonds
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	1,194	1,232
Allowance for Credit Losses	0	0
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(312)	(306)
Fair Value	882	$ 926
Short-term investments
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	28
Allowance for Credit Losses	0
Gross Unrealized Gains	0
Gross Unrealized Losses	0
Fair Value	$ 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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