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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, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Derivative [Line Items]
Gain Recognized in Income (Loss)	$ (629)	$ 3,931	$ (1,353)	$ 6,038
Total Return Swap [Member] | Net realized investment (losses) gains [Member]
Derivative [Line Items]
Gain Recognized in Income (Loss)	(1,634)	2,581	(2,654)	3,744
Equity contracts [Member] | Net realized investment (losses) gains [Member]
Derivative [Line Items]
Gain Recognized in Income (Loss)	$ 1,005	$ 1,350	$ 1,301	$ 2,294

X

- 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

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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.

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