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Investment Securities - Investments In Private Equity Funds Subject to Lock-Up Periods (Details) - USD ($) $ in Millions | 3 Months Ended |
--- | --- | ---
Mar. 31, 2025 | Dec. 31, 2024
Debt and Equity Securities, FV-NI [Line Items] |  |
1 – 3 years | $ 14.6 |
3 – 5 years | 51.5 |
5 – 10 years | 149.6 |
>10 years | 24.9 |
Total | 2,287.9 | $ 2,150.2
Private equity funds |  |
Debt and Equity Securities, FV-NI [Line Items] |  |
Total | $ 240.6 |
Hedge funds | Minimum |  |
Debt and Equity Securities, FV-NI [Line Items] |  |
Notice period | 45 days |
Hedge funds | Maximum |  |
Debt and Equity Securities, FV-NI [Line Items] |  |
Notice period | 90 days |
ILS funds |  |
Debt and Equity Securities, FV-NI [Line Items] |  |
Total | $ 71.3 | 74.0
ILS funds | Minimum |  |
Debt and Equity Securities, FV-NI [Line Items] |  |
Notice period | 30 days |
ILS funds | Maximum |  |
Debt and Equity Securities, FV-NI [Line Items] |  |
Notice period | 90 days |
Bank loan fund |  |
Debt and Equity Securities, FV-NI [Line Items] |  |
Total | $ 264.9 | $ 264.7

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