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Derivative Financial Instruments (Schedule Of Derivative Gains And Losses In The Consolidated Statements Of Operations) (Details) - Not Designated as Hedging Instrument [Member] - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
Derivative Financial Instruments [Line Items] |  |  |
Gains (Losses) Recognized in Income | $ 6,715 | $ 154 | $ 15,379
Total Return Swap [Member] | Net realized investment gains [Member] |  |  |
Derivative Financial Instruments [Line Items] |  |  |
Gains (Losses) Recognized in Income | (3,783) | (2,137) | 11,533
Equity contracts [Member] | Net realized investment gains [Member] |  |  |
Derivative Financial Instruments [Line Items] |  |  |
Gains (Losses) Recognized in Income | $ 10,498 | $ 2,291 | $ 3,846

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- Definition Derivative Financial Instruments [Line Items] + References No definition available. + Details
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- Definition Amount of increase (decrease) in the fair value of derivatives recognized in the income statement. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4A -Subparagraph (b)(1) -URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5618551-113959 + Details
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- Details
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