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Loss And Loss Adjustment Expense Reserves (Narrative) (Details) - USD ($) $ in Thousands | 9 Months Ended
--- | ---
Sep. 30, 2018 | Sep. 30, 2017
Unusual or Infrequent Item, or Both [Line Items] |  |
Prior years | $ 70,399 | $ 18,347
Catastrophe [Member] |  |
Unusual or Infrequent Item, or Both [Line Items] |  |
Loss from catastrophes | 34,000 | $ 59,000
Loss from catastrophes, net of reinsurance benefits | 24,000 |
Fire [Member] |  |
Unusual or Infrequent Item, or Both [Line Items] |  |
Loss from catastrophes | 21,000 |
Loss from catastrophes, net of reinsurance benefits | $ 10,000 |

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- Definition Loss From Catastrophes, Net of Reinsurance Benefits + References No definition available. + Details
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- Definition The charge against earnings in the period for the uninsured portion of a loss from a fire, explosion, or natural disaster (hurricane, earthquake). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.9) -URI http://asc.fasb.org/extlink&oid=115205541&loc=SL114868664-224227 + Details
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- Definition Amount, after effects of reinsurance, of expense (reversal of expense) for claims incurred in prior reporting periods and related claims settlement costs. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 50 -Paragraph 3 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=99382578&loc=d3e14764-158437 + Details
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