Investments (Details 2) (USD $) In Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Investment Gains And Losses
Other-than-temporary impairments on fixed maturity securities	$ (5,582)	$ (3,489)	$ (7,138)	$ (10,919)
Portion of loss recognized in accumulated other comprehensive income (before taxes)	292	(139)	292	2,205
Net other-than-temporary impairment losses on fixed maturities recognized in earnings	(5,290)	(3,628)	(6,846)	(8,714)
Impairment Losses On Equity Securities	(3,680)	(10)	(3,680)	(32)
Gain on investment activity	28,208	19,363	57,584	35,462
Loss on investment activity	(6,653)	(5,662)	(13,567)	(14,194)
Other impairment losses	(3,186)	(1,165)	(2,610)	(2,395)
Derivatives And Other Investments Net	17,989	14,094	120,127	144,050
Net gains (losses)	$ 27,388	$ 22,992	$ 151,008	$ 154,177

Net realized gains or losses on investments during the period related to the change in value of embedded derivatives and other realized gains and losses not otherwise categorized.

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Impairment losses on equity securities

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Other impairment losses and change in mortgage loan provision.

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The amount of other than temporary impairment (OTTI) losses on equity securities, OTTI related to credit losses on debt securities, and OTTI losses on debt securities when the entity intends to sell the securities or it is more likely than not that the entity will be required to sell the securities before recovery of its amortized cost basis. Additionally, this item includes OTTI losses recognized during the period on investments accounted for under the cost method of accounting.

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Other Than Temporary Impairments On Fixed Maturity Securities Transferred To Other Comprehensive Loss

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This item represents the gross profit realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 115
-Paragraph 21
-Subparagraph a

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This item represents the gross loss realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 115
-Paragraph 21
-Subparagraph a

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This element represents the amount of loss recognized for other than temporary impairments of investments in debt and equity securities.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 115
-Paragraph 16

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The net realized gains or losses on investments during the period.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 04
-Paragraph 3
-Subparagraph a
-Article 7

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