Reinsurance - Premium Details (Details) - 2017	Dec. 31, 2020
Radnor Re 2018-1 Ltd.
Effects of Reinsurance [Line Items]
Risk margin increase after optional termination date	50.00%
Panel of Reinsurers
Effects of Reinsurance [Line Items]
Reinsurance premium increase after options termination date	50.00%

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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