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Investment Information - Other investments, at fair value (Details) - USD ($) $ in Millions | Mar. 31, 2024 | Dec. 31, 2023
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Schedule Of Other Investments [Line Items] |  |
Other investments, at fair value | $ 2,886 | $ 2,488
Other investments |  |
Schedule Of Other Investments [Line Items] |  |
Other investments, at fair value | 1,914 | 1,777
Lending |  |
Schedule Of Other Investments [Line Items] |  |
Other investments, at fair value | 442 | 427
Investment grade fixed income |  |
Schedule Of Other Investments [Line Items] |  |
Other investments, at fair value | 799 | 754
Term loan investments |  |
Schedule Of Other Investments [Line Items] |  |
Other investments, at fair value | 344 | 272
Private equity |  |
Schedule Of Other Investments [Line Items] |  |
Other investments, at fair value | 191 | 182
Credit related funds |  |
Schedule Of Other Investments [Line Items] |  |
Other investments, at fair value | 120 | 124
Energy |  |
Schedule Of Other Investments [Line Items] |  |
Other investments, at fair value | 18 | 18
Fixed maturities |  |
Schedule Of Other Investments [Line Items] |  |
Other investments, at fair value | 930 | 683
Short term investments |  |
Schedule Of Other Investments [Line Items] |  |
Other investments, at fair value | 35 | 21
Equity securities |  |
Schedule Of Other Investments [Line Items] |  |
Other investments, at fair value | $ 7 | $ 7

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- Definition Amount of investments classified as other. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 210 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(12)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 944 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(3)(a)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478777/944-210-S99-1 + Details
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