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Investments (Gross Gains And Losses Realized On Sales Of Investments) (Details) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
Investments [Abstract] |  |  |
Equity securities, Realized Gain | $ 43,420 | $ 20,835 | $ 29,446
Equity securities, Realized Loss | (45,607) | (23,048) | (29,945)
Equity securities, Realized Gain (Loss) | (2,187) | (2,213) | (499)
Fixed maturity securities, Realized Gain | 549 | 604 | 3,327
Fixed maturity securities, Realized Loss | (3,563) | (2,701) | (19,133)
Fixed maturity securities, Realized Gain (Loss) | (3,014) | (2,097) | (15,806)
Short-term investments, Realized Gain | 61 | 21 | 6
Short-term investments, Gross Realized Losses | (2,429) | (20) | (530)
Short-term investments, Realized Gain (Loss) | $ (2,368) | $ 1 | $ (524)

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- Definition Amount of realized gain on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 9 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27357-111563 + Details
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