Fair Value Measurements - Changes in balances of Level 3 financial assets carried at fair value (Details) - USD ($) $ in Millions		12 Months Ended
May 31, 2021	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Financial assets, beginning balance		$ 1,102	$ 926	$ 3,706
Total realized/unrealized gains (losses) included in Net earnings		7	24	181
Total realized/unrealized gains (losses) included in other comprehensive income (loss)		11	(53)	(27)
Purchases and issuances		270	338	636
Sales and settlements		(109)	(117)	(565)
Transfer into Level 3		46	72	66
Transfer out of Level 3		(97)	(88)	(352)
Sale of annuity business	$ (2,719)
Financial assets, ending balance		$ 1,230	1,102	926
Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Asset, Gain (Loss), Statement of Other Comprehensive Income or Comprehensive Income [Extensible Enumeration]		OCI, Debt Securities, Available-for-Sale, Unrealized Holding Gain (Loss), before Adjustment, after Tax
Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]		Realized gains (losses) on securities
Fixed maturities
Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Financial assets, beginning balance		$ 664	600	538
Total realized/unrealized gains (losses) included in Net earnings		(4)	0	(3)
Total realized/unrealized gains (losses) included in other comprehensive income (loss)		11	(53)	(5)
Purchases and issuances		147	223	344
Sales and settlements		(70)	(93)	(210)
Transfer into Level 3		46	68	33
Transfer out of Level 3		(58)	(81)	(97)
Sale of annuity business	0
Financial assets, ending balance		736	664	600
U.S. government agency
Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Financial assets, beginning balance		0	0	0
Total realized/unrealized gains (losses) included in Net earnings		0	0	0
Total realized/unrealized gains (losses) included in other comprehensive income (loss)		0	0	0
Purchases and issuances		0	0	0
Sales and settlements		0	0	0
Transfer into Level 3		0	0	0
Transfer out of Level 3		0	0	0
Sale of annuity business	0
Financial assets, ending balance		0	0	0
State and municipal
Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Financial assets, beginning balance		5	41	39
Total realized/unrealized gains (losses) included in Net earnings		0	0	0
Total realized/unrealized gains (losses) included in other comprehensive income (loss)		0	(3)	0
Purchases and issuances		0	0	0
Sales and settlements		(1)	(1)	(4)
Transfer into Level 3		1	4	8
Transfer out of Level 3		(3)	(36)	(2)
Sale of annuity business	0
Financial assets, ending balance		2	5	41
Residential MBS
Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Financial assets, beginning balance		9	14	38
Total realized/unrealized gains (losses) included in Net earnings		1	0	(4)
Total realized/unrealized gains (losses) included in other comprehensive income (loss)		(1)	(1)	0
Purchases and issuances		0	0	6
Sales and settlements		(3)	(1)	(3)
Transfer into Level 3		5	7	6
Transfer out of Level 3		(9)	(10)	(29)
Sale of annuity business	0
Financial assets, ending balance		2	9	14
Commercial MBS
Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Financial assets, beginning balance		0	0	2
Total realized/unrealized gains (losses) included in Net earnings		0	0	0
Total realized/unrealized gains (losses) included in other comprehensive income (loss)		0	0	0
Purchases and issuances		0	0	0
Sales and settlements		0	0	0
Transfer into Level 3		0	0	0
Transfer out of Level 3		0	0	(2)
Sale of annuity business	0
Financial assets, ending balance		0	0	0
Collateralized loan obligations
Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Financial assets, beginning balance		2	0	16
Total realized/unrealized gains (losses) included in Net earnings		(2)	0	1
Total realized/unrealized gains (losses) included in other comprehensive income (loss)		1	0	0
Purchases and issuances		0	0	0
Sales and settlements		0	0	(2)
Transfer into Level 3		1	2	0
Transfer out of Level 3		(1)	0	(15)
Sale of annuity business	0
Financial assets, ending balance		1	2	0
Other asset-backed securities
Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Financial assets, beginning balance		329	278	305
Total realized/unrealized gains (losses) included in Net earnings		1	1	1
Total realized/unrealized gains (losses) included in other comprehensive income (loss)		6	(27)	0
Purchases and issuances		55	94	154
Sales and settlements		(39)	(52)	(156)
Transfer into Level 3		31	35	14
Transfer out of Level 3		(32)	0	(40)
Sale of annuity business	0
Financial assets, ending balance		351	329	278
Corporate and other
Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Financial assets, beginning balance		319	267	138
Total realized/unrealized gains (losses) included in Net earnings		(4)	(1)	(1)
Total realized/unrealized gains (losses) included in other comprehensive income (loss)		5	(22)	(5)
Purchases and issuances		92	129	184
Sales and settlements		(27)	(39)	(45)
Transfer into Level 3		8	20	5
Transfer out of Level 3		(13)	(35)	(9)
Sale of annuity business	0
Financial assets, ending balance		380	319	267
Equity securities
Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Financial assets, beginning balance		427	313	176
Total realized/unrealized gains (losses) included in Net earnings		15	29	99
Total realized/unrealized gains (losses) included in other comprehensive income (loss)		0	0	0
Purchases and issuances		121	112	78
Sales and settlements		(39)	(24)	(28)
Transfer into Level 3		0	4	0
Transfer out of Level 3		(39)	(7)	(12)
Sale of annuity business	0
Financial assets, ending balance		485	427	313
Assets of MIE
Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Financial assets, beginning balance		11	13	21
Total realized/unrealized gains (losses) included in Net earnings		(4)	(5)	0
Total realized/unrealized gains (losses) included in other comprehensive income (loss)		0	0	0
Purchases and issuances		2	3	5
Sales and settlements		0	0	0
Transfer into Level 3		0	0	1
Transfer out of Level 3		0	0	(14)
Sale of annuity business	0
Financial assets, ending balance		$ 9	11	13
Assets of discontinued annuity operations \| Annuity subsidiaries
Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Financial assets, beginning balance			$ 0	2,971
Total realized/unrealized gains (losses) included in Net earnings				85
Total realized/unrealized gains (losses) included in other comprehensive income (loss)				(22)
Purchases and issuances				209
Sales and settlements				(327)
Transfer into Level 3				32
Transfer out of Level 3				(229)
Sale of annuity business	$ (2,719)
Financial assets, ending balance				$ 0

Fair value measurement with unobservable inputs reconciliation, recurring basis, asset, disposition of subsidiaries

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

Amount of gain (loss) recognized in income from asset measured at fair value on recurring basis using unobservable input (level 3).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482106/820-10-50-2

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- Definition

Amount of gain (loss) recognized in other comprehensive income (OCI) from asset measured at fair value on recurring basis using unobservable input (level 3).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(1a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482106/820-10-50-2

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- Definition

Amount of purchases of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482106/820-10-50-2

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- Definition

Amount of sale of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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- Definition

Amount of transfer of financial instrument classified as an asset into level 3 of the fair value hierarchy.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(3)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482106/820-10-50-2

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- Definition

Amount of transfers of financial instrument classified as an asset out of level 3 of the fair value hierarchy.

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Fair value of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

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-Paragraph 2
-Subparagraph (c)
-SubTopic 10
-Topic 820
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482106/820-10-50-2

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- Definition

Indicates line item in statement in which net income is reported that includes gain (loss) from asset measured at fair value using unobservable input (level 3).

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