Recent Developments Related to COVID-19 Recent Developments Related to COVID-19 (Narrative) (Details) $ in Millions	3 Months Ended
Mar. 31, 2020 USD ($)
COVID-19 Pandemic [Member]
Causes of Increase (Decrease) in Liability for Unpaid Claims and Claims Adjustment Expense [Line Items]
Net losses and loss adjustment expenses, net of assumed reinstatement premiums	$ 325.0

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.

No definition available.

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