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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

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