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Investment Information - Other investments (Details) - USD ($) $ in Thousands | Mar. 31, 2022 | Dec. 31, 2021
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Schedule Of Other Investments [Line Items] |  |
Other investments, at fair value | $ 1,686,666 | $ 1,973,550
Fixed maturities |  |
Schedule Of Other Investments [Line Items] |  |
Other investments, at fair value | 426,187 | 416,698
Other investments |  |
Schedule Of Other Investments [Line Items] |  |
Other investments, at fair value | 1,226,808 | 1,432,553
Other investments | Lending |  |
Schedule Of Other Investments [Line Items] |  |
Other investments, at fair value | 472,099 | 536,345
Other investments | Investment grade fixed income |  |
Schedule Of Other Investments [Line Items] |  |
Other investments, at fair value | 350,217 | 147,810
Other investments | Term loan investments |  |
Schedule Of Other Investments [Line Items] |  |
Other investments, at fair value | 160,945 | 484,950
Other investments | Private equity |  |
Schedule Of Other Investments [Line Items] |  |
Other investments, at fair value | 98,471 | 91,126
Other investments | Energy |  |
Schedule Of Other Investments [Line Items] |  |
Other investments, at fair value | 81,693 | 81,692
Other investments | Credit related funds |  |
Schedule Of Other Investments [Line Items] |  |
Other investments, at fair value | 63,383 | 70,278
Other investments | Infrastructure |  |
Schedule Of Other Investments [Line Items] |  |
Other investments, at fair value | 0 | 20,352
Short-term investments |  |
Schedule Of Other Investments [Line Items] |  |
Other investments, at fair value | 12,371 | 97,806
Equity securities |  |
Schedule Of Other Investments [Line Items] |  |
Other investments, at fair value | $ 21,300 | $ 26,493

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