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Investment Information - Other investments (Details) - Fair value option - USD ($) $ in Thousands | Sep. 30, 2020 | Dec. 31, 2019
--- | --- | ---
Schedule Of Other Investments [Line Items] |  |
Other investments | $ 2,169,897 | $ 2,429,316
Term loan investments |  |
Schedule Of Other Investments [Line Items] |  |
Other investments | 1,202,526 | 1,326,018
Lending |  |
Schedule Of Other Investments [Line Items] |  |
Other investments | 575,623 | 602,841
Credit related funds |  |
Schedule Of Other Investments [Line Items] |  |
Other investments | 98,121 | 123,020
Energy |  |
Schedule Of Other Investments [Line Items] |  |
Other investments | 65,330 | 97,402
Investment grade fixed income |  |
Schedule Of Other Investments [Line Items] |  |
Other investments | 114,784 | 151,594
Infrastructure |  |
Schedule Of Other Investments [Line Items] |  |
Other investments | 60,579 | 61,786
Private equity |  |
Schedule Of Other Investments [Line Items] |  |
Other investments | 34,983 | 49,376
Real estate |  |
Schedule Of Other Investments [Line Items] |  |
Other investments | $ 17,951 | $ 17,279

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