Investments (ACL for Fixed Maturity Securities AFS by Sector) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022
Debt Securities, Available-for-sale, Allowance for Credit Loss [Line Items]
Allowance, beginning of period	$ 183	$ 91
ACL not previously recorded	47	292
Changes for securities with previously recorded ACL	(9)	(29)
Securities sold or exchanged	(37)	(139)
Debt Securities Available for sale Allowance for Credit Loss, Foreign Currency Translation		10
Write-offs		(22)
Allowance, end of period	184	183
U.S. corporate
Debt Securities, Available-for-sale, Allowance for Credit Loss [Line Items]
Allowance, beginning of period	29	30
ACL not previously recorded	36	13
Changes for securities with previously recorded ACL	7	17
Securities sold or exchanged	(4)	(9)
Debt Securities Available for sale Allowance for Credit Loss, Foreign Currency Translation		0
Write-offs		(22)
Allowance, end of period	68	29
Foreign corporate
Debt Securities, Available-for-sale, Allowance for Credit Loss [Line Items]
Allowance, beginning of period	5	28
ACL not previously recorded	0	67
Changes for securities with previously recorded ACL	0	2
Securities sold or exchanged	(3)	(93)
Debt Securities Available for sale Allowance for Credit Loss, Foreign Currency Translation		(1)
Write-offs		0
Allowance, end of period	2	5
Foreign government
Debt Securities, Available-for-sale, Allowance for Credit Loss [Line Items]
Allowance, beginning of period	130	19
ACL not previously recorded	0	207
Changes for securities with previously recorded ACL	(23)	(48)
Securities sold or exchanged	(19)	(37)
Debt Securities Available for sale Allowance for Credit Loss, Foreign Currency Translation		11
Write-offs		0
Allowance, end of period	88	130
RMBS
Debt Securities, Available-for-sale, Allowance for Credit Loss [Line Items]
Allowance, beginning of period	0	0
ACL not previously recorded	2	0
Changes for securities with previously recorded ACL	(1)	0
Securities sold or exchanged	0	0
Debt Securities Available for sale Allowance for Credit Loss, Foreign Currency Translation		0
Write-offs		0
Allowance, end of period	1	0
ABS & CLO
Debt Securities, Available-for-sale, Allowance for Credit Loss [Line Items]
Allowance, beginning of period	0	0
ACL not previously recorded	7	0
Changes for securities with previously recorded ACL	0	0
Securities sold or exchanged	0	0
Debt Securities Available for sale Allowance for Credit Loss, Foreign Currency Translation		0
Write-offs		0
Allowance, end of period	7	0
CMBS
Debt Securities, Available-for-sale, Allowance for Credit Loss [Line Items]
Allowance, beginning of period	19	14
ACL not previously recorded	2	5
Changes for securities with previously recorded ACL	8	0
Securities sold or exchanged	(11)	0
Debt Securities Available for sale Allowance for Credit Loss, Foreign Currency Translation		0
Write-offs		0
Allowance, end of period	$ 18	$ 19

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Amount of allowance for credit loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
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+ References

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+ References

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Amount of decrease in allowance for credit loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale) from sale.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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