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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 | 9 Months Ended
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Sep. 30, 2017 | Sep. 30, 2016 | Sep. 30, 2017 | Sep. 30, 2016
Derivative [Line Items] |  |  |  |
Gain Recognized in Income (Loss) | $ 675 | $ 5,202 | $ (678) | $ 11,239
Total Return Swap [Member] | Net realized investment (losses) gains [Member] |  |  |  |
Derivative [Line Items] |  |  |  |
Gain Recognized in Income (Loss) | 118 | 4,172 | (2,535) | 7,915
Equity contracts [Member] | Net realized investment (losses) gains [Member] |  |  |  |
Derivative [Line Items] |  |  |  |
Gain Recognized in Income (Loss) | $ 557 | $ 1,030 | $ 1,857 | $ 3,324

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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/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4A -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5618551-113959 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4C -Subparagraph (a),(c),(d),(e) -URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5624171-113959 + Details
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- Definition 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. + References No definition available. + Details
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