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Investments (Gross Credit Loss Impairments of Fixed Maturity Securities for Which a Portion of the OTTI Charge was Recognized in OCI) (Details) (USD $) In Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Investments [Abstract]
Balance, beginning of period	$ 14,368	$ 24,737	$ 17,723	$ 22,189
Addition for the amount related to credit loss for which an OTTI was not previously recognized	0	2,004	0	2,134
Reductions for securities sold during the period	0	(2,990)	0	(2,990)
Reductions for securities for which the amount previously recognized in OCI was recognized in earnings because of intention or potential requirement to sell before recovery of amortized cost	0	0	0	0
Reductions for securities for which the entire amount previously recognized in OCI was recognized in earnings due to a decrease in cash flows expected	(372)	(4,358)	(3,954)	(4,652)
Additional increases to the amount related to credit loss for which an OTTI was previously recognized	28	950	255	3,662
Accretion of credit loss impairments previously recognized due to an increase in cash flows expected to be collected	0	0	0	0
Balance, end of period	$ 14,024	$ 20,343	$ 14,024	$ 20,343

X

- Definition

This item represents accretion of credit loss impairments previously recognized due to an increase in cash flow expected to be collected on securities for which an other-than-temporary impairment charge was recognized in other comprehensive income.

+ Details

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- Definition

This item represents additional credit losses recognized in earnings on securities for which an other-than-temporary impairment was previously recognized in other comprehensive income.

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- Definition

This item represents credit losses during the period on securities for which an other-than-temporary impairment was not previously recognized in other comprehensive income.

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- Definition

The cumulative amount of credit loss impairments on fixed maturity securities for which a portion of the other-than-temporary impairment charge was recognized in other comprehensive income.

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- Definition

This item represents the removal of a credit loss from the table due to the fact that the other-than-temporary impairment charge that was previously recognized in other comprehensive income was recognized in earnings during the period due to the company's intention or potential requirement to sell before recovery of amortized cost.

+ Details

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- Definition

This item represents the removal of a credit loss from the table due to the fact that the other-than-temporary charge that was previously recognized in other comprehensive income was recognized in earnings during the period due to a decrease in the securities expected cash flows.

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- Definition

This item represents a decrease to the cumulative amount of credit losses recognized in earnings on fixed maturity securities for which a portion of the other-than-temporary impairment charge was recognized in other comprehensive income due to the sale of the securities during the reporting period.

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