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Investments (Summary Of Net Realized Investment Gains And The Change In Net Unrealized Gains On Investments) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Gain (Loss) on Investments [Line Items]
Realized gains	$ 9,509	$ 20,098	$ 27,707	$ 46,052
Realized losses	(3,404)	(12,978)	(16,031)	(21,538)
Other-than-temporary impairment losses recognized in net income	0	(1,007)	(5,092)	(1,007)
Net realized investment gains	6,105	7,120	11,676	24,514
Change in net unrealized gains on investments	(351,332)	299,692	(186,669)	514,957
Sales Of Fixed Maturities [Member]
Gain (Loss) on Investments [Line Items]
Realized gains	770	1,642	2,338	5,643
Realized losses	(97)	(8,246)	(221)	(16,148)
Sales Of Equity Securities [Member]
Gain (Loss) on Investments [Line Items]
Realized gains	7,000	14,051	22,956	26,094
Realized losses	(113)	(99)	(272)	(143)
Other [Member]
Gain (Loss) on Investments [Line Items]
Realized gains	1,739	4,405	2,413	14,315
Realized losses	(3,194)	(3,626)	(10,446)	(4,240)
Fixed Maturities [Member]
Gain (Loss) on Investments [Line Items]
Other-than-temporary impairment losses recognized in net income	0	(197)	0	(200)
Change in net unrealized gains on investments	(286,551)	147,439	(180,213)	296,250
Equity Securities [Member]
Gain (Loss) on Investments [Line Items]
Other-than-temporary impairment losses recognized in net income	0	(810)	(5,092)	(800)
Change in net unrealized gains on investments	(64,792)	152,256	(6,447)	218,709
Short-Term Investments [Member]
Gain (Loss) on Investments [Line Items]
Change in net unrealized gains on investments	$ 11	$ (3)	$ (9)	$ (2)

X

- Definition

This item represents the pretax change in net unrealized holding gain (loss) on available-for-sale securities that has been included in accumulated other comprehensive income, a separate component of shareholders' equity, during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef



-Publisher FASB



-Name Accounting Standards Codification



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-Section 50



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This item represents the difference between the gross realized gains and losses realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities. Additionally, this item would include any losses recognized for other than temporary impairments (OTTI) of the subject investments in debt and equity securities.

+ References

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The amount of other than temporary impairment losses on investments in debt and equity securities categorized as Available-for-sale which have been recognized in earnings during the period. Such impairment losses consist of other than temporary impairments (OTTI) on equity securities, credit losses on investments in debt securities, and when the entity intends to sell an impaired debt security or it is more likely than not that the entity will be required to sell the impaired debt security before recovery of its amortized cost basis.

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