Derivatives (Fair Value Hedges) (Details) - Designated as Hedging Instrument [Member] - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Fixed maturity securities AFS
Derivative Instruments, Gain (Loss) [Line Items]
Hedged Asset, Discontinued Fair Value Hedge, Cumulative Increase (Decrease)	$ (105)	$ (111)
Debt Instruments, Carrying Amount	445	454
Hedged Asset, Fair Value Hedge, Cumulative Increase (Decrease)	3	3
Mortgages
Derivative Instruments, Gain (Loss) [Line Items]
Debt Instruments, Carrying Amount	285	359
Hedged Asset, Fair Value Hedge, Cumulative Increase (Decrease)	(8)	(11)
Future policy benefits [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Debt Instruments, Carrying Amount	2,656	2,863
Hedged Asset, Fair Value Hedge, Cumulative Increase (Decrease)	298	191
Policyholder Account Balances [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Debt Instruments, Carrying Amount	1,720	1,911
Hedged Asset, Fair Value Hedge, Cumulative Increase (Decrease)	$ 148	$ 25

Debt Instruments, Carrying Amount

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4E
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480434/815-10-50-4E

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- Definition

Amount of cumulative increase (decrease) in fair value of hedged asset in fair value hedge, attributable to hedged risk, remaining after discontinued hedge.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 181
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480401/815-10-55-181

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4EE
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480434/815-10-50-4EE

+ Details

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- Definition

Amount of cumulative increase (decrease) in fair value of hedged asset in fair value hedge, attributable to hedged risk.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 181
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480401/815-10-55-181

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4EE
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480434/815-10-50-4EE

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