Derivatives (Fair Value Hedges) (Details) - Designated as Hedging Instrument [Member] - USD ($) $ in Millions	Dec. 31, 2022	Dec. 31, 2021
Fixed Maturities [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Hedged Asset, Discontinued Fair Value Hedge, Cumulative Increase (Decrease)	$ (136)	$ (161)
Debt Instruments, Carrying Amount	1,411	2,164
Hedged Asset, Fair Value Hedge, Cumulative Increase (Decrease)	1	(1)
Mortgages [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Debt Instruments, Carrying Amount	331	634
Hedged Asset, Fair Value Hedge, Cumulative Increase (Decrease)	(19)	3
Future policy benefits [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Debt Instruments, Carrying Amount	(3,524)	(4,735)
Hedged Asset, Fair Value Hedge, Cumulative Increase (Decrease)	276	(877)
Policyholder Account Balances [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Debt Instruments, Carrying Amount	(1,080)	0
Hedged Asset, Fair Value Hedge, Cumulative Increase (Decrease)	$ 27	$ 0

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

No definition available.

+ 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, remaining after discontinued hedge.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4EE
-Subparagraph (d)
-URI https://asc.fasb.org/extlink&oid=125515794&loc=SL109999712-113959

+ 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/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4EE
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=125515794&loc=SL109999712-113959

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