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Investment Information - Equity method investments (Details) - USD ($) $ in Thousands | Sep. 30, 2020 | Dec. 31, 2019
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Schedule of Equity Method Investments [Line Items] |  |
Investments accounted for using the equity method | $ 1,883,702 | $ 1,660,396
Credit related funds |  |
Schedule of Equity Method Investments [Line Items] |  |
Investments accounted for using the equity method | 687,178 | 428,437
Equity securities |  |
Schedule of Equity Method Investments [Line Items] |  |
Investments accounted for using the equity method | 323,670 | 293,686
Real estate |  |
Schedule of Equity Method Investments [Line Items] |  |
Investments accounted for using the equity method | 246,998 | 246,851
Lending |  |
Schedule of Equity Method Investments [Line Items] |  |
Investments accounted for using the equity method | 141,305 | 202,690
Private equity |  |
Schedule of Equity Method Investments [Line Items] |  |
Investments accounted for using the equity method | 214,357 | 144,983
Infrastructure |  |
Schedule of Equity Method Investments [Line Items] |  |
Investments accounted for using the equity method | 156,029 | 235,033
Energy |  |
Schedule of Equity Method Investments [Line Items] |  |
Investments accounted for using the equity method | $ 114,165 | $ 108,716

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