Fair Value Measurements - Changes in balances of Level 3 financial liabilities carried at fair value (Details) - USD ($) $ in Millions		12 Months Ended
May 31, 2021	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Financial liabilities, beginning balance		$ (25)	$ (23)	$ (3,933)
Total realized/unrealized gains (losses) included in Net earnings		23	0	(223)
Total realized/unrealized gains (losses) included in other comprehensive income (loss)		0	0	0
Purchases and issuances		0	(2)	(169)
Sales and settlements		0	0	159
Transfer into Level 3		0	0	0
Transfer out of Level 3		0	0	0
Sale of annuity business	$ 4,143
Financial liabilities, ending balance		(2)	$ (25)	(23)
Fair Value, Liability, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]			Realized gains (losses) on securities
Contingent consideration - acquisitions
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Financial liabilities, beginning balance		(25)	$ (23)	0
Total realized/unrealized gains (losses) included in Net earnings		23	0	0
Total realized/unrealized gains (losses) included in other comprehensive income (loss)		0	0	0
Purchases and issuances		0	(2)	(23)
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 liabilities, ending balance		$ (2)	(25)	(23)
Liabilities of discontinued annuity operations \| Annuity subsidiaries
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Financial liabilities, beginning balance			$ 0	(3,933)
Total realized/unrealized gains (losses) included in Net earnings				(223)
Total realized/unrealized gains (losses) included in other comprehensive income (loss)				0
Purchases and issuances				(146)
Sales and settlements				159
Transfer into Level 3				0
Transfer out of Level 3				0
Sale of annuity business	$ 4,143
Financial liabilities, ending balance				$ 0

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

No definition available.

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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.

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- Definition

Amount of transfers of financial instrument classified as a liability 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 a liability out of level 3 of the fair value hierarchy.

+ References

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- Definition

Amount of gain (loss) recognized in income from liability 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 liability 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 issuances of financial instrument classified as a liability 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 settlements of financial instrument classified as a liability 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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- Definition

Fair value of financial instrument classified as a liability 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
-Section 50
-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 liability measured at fair value using unobservable input (level 3).

+ References

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