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Investment Securities - Lloyd's Trust Deposits, Bank Loan Fund, and Insurance-Linked Securities Funds (Details) - USD ($) $ in Millions | 9 Months Ended |
--- | --- | ---
Sep. 30, 2022 | Dec. 31, 2021
Debt and Equity Securities, FV-NI [Line Items] |  |
Investments held in trusts | $ 455.1 | $ 479.5
Hedge funds | Minimum |  |
Debt and Equity Securities, FV-NI [Line Items] |  |
Redemptions and advanced redemption notice period | 45 days |
Hedge funds | 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 | $ 155.7 |
Lloyds Bank |  |
Debt and Equity Securities, FV-NI [Line Items] |  |
Fair value investments | 311.4 | $ 342.8
Investments held in trusts | 117.8 |
ILS funds |  |
Debt and Equity Securities, FV-NI [Line Items] |  |
Fair value investments | $ 49.4 |
ILS funds | Minimum |  |
Debt and Equity Securities, FV-NI [Line Items] |  |
Redemptions and advanced redemption notice period | 30 days |
ILS funds | Maximum |  |
Debt and Equity Securities, FV-NI [Line Items] |  |
Redemptions and advanced redemption notice period | 90 days |

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