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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

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- Definition Fair value measurement with unobservable inputs reconciliation, recurring basis, liability, disposition of subsidiaries + References No definition available. + Details
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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 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 + Details
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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 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 + Details
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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 + Details
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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 + Details
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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 + Details
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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 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 + Details
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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 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 + Details
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