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Investment Securities - Investments In Private Equity Funds Subject to Lock-Up Periods (Details) - USD ($) $ in Millions | 12 Months Ended |
--- | --- | ---
Dec. 31, 2021 | Dec. 31, 2020
Investment securities |  |
Investments held in trusts | $ 479.5 | $ 432.4
Lloyds Bank |  |
Investment securities |  |
Investments held in trusts | 113.8 |
Fair value investments | 342.8 |
Bank loan fund |  |
Investment securities |  |
Fair value investments | 163.0 |
ILS funds |  |
Investment securities |  |
Fair value investments | 51.9 |
Short-term investments |  |
Investment securities |  |
Investments pledged as collateral | 50.0 |
Private equity funds |  |
Investment securities |  |
Trading security, fair value | 141.8 |
1 – 3 years | Private equity funds |  |
Investment securities |  |
Trading security, fair value | 0.1 |
3 – 5 years | Private equity funds |  |
Investment securities |  |
Trading security, fair value | 13.9 |
5 – 10 years | Private equity funds |  |
Investment securities |  |
Trading security, fair value | 116.3 |
>10 years | Private equity funds |  |
Investment securities |  |
Trading security, fair value | $ 11.5 |
Minimum |  |
Investment securities |  |
Redemptions and advanced redemption notice period | 30 days |
Maximum |  |
Investment securities |  |
Redemptions and advanced redemption notice period | 90 days |

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