Commitments and Contingencies (Narrative) (Details) - USD ($) $ in Millions		12 Months Ended
Apr. 28, 2020	Dec. 31, 2020
Loss Contingencies [Line Items]
Exposure to earthquake loss	$ 78.0
Reduction in premiums written, net		$ 128.0

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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