Sale of Subsidiary (Narrative) (Details) - Discontinued Operations, Disposed of by Sale - Avon $ in Thousands	12 Months Ended
Dec. 31, 2018 USD ($)
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Percentage of investment in Eastern Re. Ltd transferred	40.00%
Net cash proceeds	$ 25,159

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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