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Investment Securities - Other Long-Term Investments (Details) - USD ($) $ in Millions | Dec. 31, 2022 | Dec. 31, 2021
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Investment securities |  |
Other long-term investments | $ 1,488.0 | $ 1,377.8
Kudu |  |
Investment securities |  |
Other long-term investments | 695.9 | 669.5
PassportCard/DavidShield |  |
Investment securities |  |
Other long-term investments | 135.0 | 120.0
Elementum Holdings L.P. |  |
Investment securities |  |
Other long-term investments | 30.0 | 45.0
Other unconsolidated entities |  |
Investment securities |  |
Other long-term investments | 37.2 | 34.4
Total unconsolidated entities |  |
Investment securities |  |
Other long-term investments | 898.1 | 868.9
Private equity funds and hedge funds |  |
Investment securities |  |
Other long-term investments | 197.8 | 153.8
Bank loan fund |  |
Investment securities |  |
Other long-term investments | 174.8 | 163.0
Lloyd’s trust deposits |  |
Investment securities |  |
Other long-term investments | 137.4 | 113.8
ILS funds |  |
Investment securities |  |
Other long-term investments | 49.3 | 51.9
Private debt instruments |  |
Investment securities |  |
Other long-term investments | 9.6 | 14.1
Other |  |
Investment securities |  |
Other long-term investments | $ 21.0 | $ 12.3

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