Goodwill (Narrative) (Details) $ in Thousands	6 Months Ended	12 Months Ended
Jun. 30, 2021 USD ($) reportingUnit segment	Dec. 31, 2020 USD ($)
Goodwill [Line Items]
Number of reportable segments (in segments) \| segment	5
Number of reporting units \| reportingUnit	2
Goodwill impairment	$ 0	$ (161,115)
Specialty P&C
Goodwill [Line Items]
Goodwill impairment	$ 0	$ (161,115)

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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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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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.

+ References

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-Publisher FASB
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-Topic 280
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Number of reporting units tested for impairment of goodwill. A reporting unit is an operating segment or one level below an operating segment.

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