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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, unless otherwise specified | 3 Months Ended | 6 Months Ended
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Jun. 30, 2013 | Jun. 30, 2012 | Jun. 30, 2013 | Jun. 30, 2012
Derivative Financial Instruments [Line Items] |  |  |  |
Gain Recognized in Income (Loss) | $ 961 | $ 515 | $ 1,282 | $ 1,856
Interest rate swap agreements [Member] | Other revenue [Member] |  |  |  |
Derivative Financial Instruments [Line Items] |  |  |  |
Gain Recognized in Income (Loss) | 0 | 147 | 103 | 271
Equity contracts [Member] | Net realized investment (losses) gains [Member] |  |  |  |
Derivative Financial Instruments [Line Items] |  |  |  |
Gain Recognized in Income (Loss) | $ 961 | $ 368 | $ 1,179 | $ 1,585

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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=7476318&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=7476318&loc=SL5624171-113959 + Details
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