Investments (Details 5) (USD $) In Millions, unless otherwise specified	Jun. 30, 2011	Dec. 31, 2010
Concentrations of Credit Risk (Fixed Maturity Securities) - U.S. and Foreign Corporate Securities
Fixed maturity securities available-for-sale, at estimated fair value (amortized cost: $330,903 and $317,617, respectively; includes $3,357 and $3,330, respectively, relating to variable interest entities)	$ 341,744	$ 324,797
Largest exposure to a single issuer [Member] \| Corporate fixed maturity securities [Member]
Concentrations of Credit Risk (Fixed Maturity Securities) - U.S. and Foreign Corporate Securities
Fixed maturity securities available-for-sale, at estimated fair value (amortized cost: $330,903 and $317,617, respectively; includes $3,357 and $3,330, respectively, relating to variable interest entities)	2,207	2,291
% of Total Investments	0.50%	0.50%
Holdings in ten issuers with the largest exposures [Member] \| Corporate fixed maturity securities [Member]
Concentrations of Credit Risk (Fixed Maturity Securities) - U.S. and Foreign Corporate Securities
Fixed maturity securities available-for-sale, at estimated fair value (amortized cost: $330,903 and $317,617, respectively; includes $3,357 and $3,330, respectively, relating to variable interest entities)	13,328	14,247
% of Total Investments	2.80%	3.10%
Corporate fixed maturity securities [Member]
Concentrations of Credit Risk (Fixed Maturity Securities) - U.S. and Foreign Corporate Securities
Fixed maturity securities available-for-sale, at estimated fair value (amortized cost: $330,903 and $317,617, respectively; includes $3,357 and $3,330, respectively, relating to variable interest entities)	$ 167,335	$ 159,660

- Definition

For an unclassified balance sheet, total of debt securities categorized neither as held-to-maturity nor trading. Such securities are reported at fair value; unrealized gains and losses of such securities are excluded from earnings and included in other comprehensive income, a separate component of shareholders' equity, unless the Available-for-sale Security is designated as a hedge or is determined to have had an other than temporary decline in fair value below its amortized cost basis. All or a portion of the unrealized holding gain or loss of an Available-for-sale Security that is designated as being hedged in a fair value hedge shall be recognized in earnings during the period of the hedge, as should other than temporary declines in fair value below costs basis.

+ References+ Details