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Investment Securities - Lloyd's Trust Deposits, Bank Loan Fund, and Insurance-Linked Securities Funds (Details) - USD ($) $ in Millions | 3 Months Ended |
--- | --- | ---
Mar. 31, 2022 | Dec. 31, 2021
Debt and Equity Securities, FV-NI [Line Items] |  |
Investments held in trusts | $ 463.7 | $ 479.5
Minimum |  |
Debt and Equity Securities, FV-NI [Line Items] |  |
Redemptions and advanced redemption notice period | 30 days |
Maximum |  |
Debt and Equity Securities, FV-NI [Line Items] |  |
Redemptions and advanced redemption notice period | 90 days |
Bank loan fund |  |
Debt and Equity Securities, FV-NI [Line Items] |  |
Fair value investments | $ 162.4 |
Lloyds Bank |  |
Debt and Equity Securities, FV-NI [Line Items] |  |
Fair value investments | 305.6 | $ 342.8
Investments held in trusts | 113.2 |
ILS funds |  |
Debt and Equity Securities, FV-NI [Line Items] |  |
Fair value investments | $ 51.7 |

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