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Derivative Financial Instruments (Schedule Of Derivative Gains And Losses In The Consolidated Statements Of Operations) (Details) - Not Designated as Hedging Instrument [Member] - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Derivative Financial Instruments [Line Items]
Gains (Losses) Recognized in Income	$ 22,306	$ 7,378	$ 6,715
Total Return Swap [Member] | Net realized investment gains [Member]
Derivative Financial Instruments [Line Items]
Gains (Losses) Recognized in Income	0	1,039	(3,783)
Equity contracts [Member] | Net realized investment gains [Member]
Derivative Financial Instruments [Line Items]
Gains (Losses) Recognized in Income	$ 22,306	$ 6,339	$ 10,498

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- Definition

Derivative Financial Instruments [Line Items]

+ References

No definition available.

+ Details

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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=121590274&loc=SL5618551-113959

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