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Investment Securities - Investments In Private Equity Funds Subject to Lock-Up Periods (Details) - USD ($) $ in Millions | Dec. 31, 2023 | Dec. 31, 2022
--- | --- | ---
Investment securities |  |
1 – 3 years | $ 4.5 |
3 – 5 years | 71.0 |
5 – 10 years | 155.4 |
>10 years | 17.7 |
Total | 1,998.2 | $ 1,488.0
Private equity funds |  |
Investment securities |  |
Total | $ 248.6 |

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