Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

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Goodwill (Narrative) (Details) $ in Thousands	3 Months Ended		9 Months Ended
Goodwill (Narrative) (Details) $ in Thousands	Sep. 30, 2020 USD ($)	Sep. 30, 2019 USD ($)	Sep. 30, 2020 USD ($) reporting_unit segment	Sep. 30, 2019 USD ($)
Goodwill [Line Items]
Number of reportable segments (in segments) \| segment			5
Number of reporting units \| reporting_unit			3
Goodwill impairment	$ (161,115)	$ 0	$ (161,115)	$ 0
Specialty P&C
Goodwill [Line Items]
Goodwill impairment	$ (161,100)		$ (161,115)