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, 2021	Dec. 31, 2020	Dec. 31, 2019
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Financial liabilities, Beginning Balance		$ (3,933)	$ (3,730)	$ (2,720)
Total realized/unrealized gains (losses) included in Net earnings		(223)	(283)	(919)
Total realized/unrealized gains (losses) included in other comprehensive income (loss)		0	0	0
Purchases and issuances		(169)	(242)	(333)
Sales and settlements		159	322	242
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		(23)	(3,933)	(3,730)
Contingent consideration - acquisitions
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Financial liabilities, Beginning Balance		0
Total realized/unrealized gains (losses) included in Net earnings		0
Total realized/unrealized gains (losses) included in other comprehensive income (loss)		0
Purchases and issuances		(23)
Sales and settlements		0
Transfer into Level 3		0
Transfer out of Level 3		0
Sale of annuity business	0
Financial liabilities, Ending Balance		(23)	0
Liabilities of discontinued annuity operations \| Annuity subsidiaries
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Financial liabilities, Beginning Balance		(3,933)	(3,730)	(2,720)
Total realized/unrealized gains (losses) included in Net earnings		(223)	(283)	(919)
Total realized/unrealized gains (losses) included in other comprehensive income (loss)		0	0	0
Purchases and issuances		(146)	(242)	(333)
Sales and settlements		159	322	242
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		$ 0	$ (3,933)	$ (3,730)

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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(3)
-URI http://asc.fasb.org/extlink&oid=123874694&loc=d3e19207-110258

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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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=123874694&loc=d3e19207-110258

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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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1a)
-URI http://asc.fasb.org/extlink&oid=123874694&loc=d3e19207-110258

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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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=123874694&loc=d3e19207-110258

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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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=123874694&loc=d3e19207-110258

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