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Derivative Financial Instruments (Schedule Of Derivative Gains And Losses In The Consolidated Statements Of Operations) (Details) - Derivatives Not Designated as Hedging Instrument [Member] - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2018 | Jun. 30, 2017 | Jun. 30, 2018 | Jun. 30, 2017
Derivative [Line Items] |  |  |  |
Gain Recognized in Income (Loss) | $ 2,487 | $ (629) | $ 6,011 | $ (1,353)
Total Return Swap [Member] | Net realized investment (losses) gains [Member] |  |  |  |
Derivative [Line Items] |  |  |  |
Gain Recognized in Income (Loss) | (320) | (1,634) | 280 | (2,654)
Equity contracts [Member] | Net realized investment (losses) gains [Member] |  |  |  |
Derivative [Line Items] |  |  |  |
Gain Recognized in Income (Loss) | $ 2,807 | $ 1,005 | $ 5,731 | $ 1,301

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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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