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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, 2016 | Sep. 30, 2015 | Sep. 30, 2016 | Sep. 30, 2015
Derivative [Line Items] |  |  |  |
Gain Recognized in Income (Loss) | $ 5,202 | $ (3,727) | $ 11,239 | $ 1,509
Total Return Swap [Member] | Other revenue [Member] |  |  |  |
Derivative [Line Items] |  |  |  |
Gain Recognized in Income (Loss) | 4,172 | (4,422) | 7,915 | (710)
Equity contracts [Member] | Net realized investment (losses) gains [Member] |  |  |  |
Derivative [Line Items] |  |  |  |
Gain Recognized in Income (Loss) | $ 1,030 | $ 695 | $ 3,324 | $ 2,219

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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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