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Investment Securities - Other Long-Term Investments (Details) - USD ($) $ in Millions | Dec. 31, 2021 | Dec. 31, 2020
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Investment securities |  |
Other long-term investments | $ 1,377.8 | $ 786.8
Kudu |  |
Investment securities |  |
Other long-term investments | 669.5 | 400.6
PassportCard/DavidShield |  |
Investment securities |  |
Other long-term investments | 120.0 | 95.0
Elementum Holdings L.P. |  |
Investment securities |  |
Other long-term investments | 45.0 | 55.1
Other unconsolidated entities |  |
Investment securities |  |
Other long-term investments | 34.4 | 42.4
Total unconsolidated entities |  |
Investment securities |  |
Other long-term investments | 868.9 | 593.1
Bank loan fund |  |
Investment securities |  |
Other long-term investments | 163.0 | 0.0
Private equity funds and hedge funds |  |
Investment securities |  |
Other long-term investments | 153.8 | 121.2
Lloyd’s trust deposits |  |
Investment securities |  |
Other long-term investments | 113.8 | 0.0
ILS funds |  |
Investment securities |  |
Other long-term investments | 51.9 | 51.4
Private debt investments |  |
Investment securities |  |
Other long-term investments | 14.1 | 21.1
Other |  |
Investment securities |  |
Other long-term investments | $ 12.3 | $ 0.0

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