Investments (Details 6) (USD $) In Millions, unless otherwise specified	Jun. 30, 2011	Dec. 31, 2010
Concentration of Credit Risk (Fixed Maturity Securities) - RMBS
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
Fixed maturity securities [Member]
Concentration of Credit Risk (Fixed Maturity Securities) - RMBS
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
% of Total	100.00%	100.00%
Concentration of credit risk debt securities [Member] | RMBS [Member]
Concentration of Credit Risk (Fixed Maturity Securities) - RMBS
% of Total	100.00%	100.00%
Collateralized mortgage obligations [Member] | RMBS [Member]
Concentration of Credit Risk (Fixed Maturity Securities) - RMBS
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)	23,011	22,303
% of Total	52.80%	49.90%
Agency [Member] | RMBS [Member]
Concentration of Credit Risk (Fixed Maturity Securities) - RMBS
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)	32,774	34,254
% of Total	75.30%	76.60%
Prime [Member] | RMBS [Member]
Concentration of Credit Risk (Fixed Maturity Securities) - RMBS
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)	6,016	6,258
% of Total	13.80%	14.00%
RMBS Pass-through securities [Member] | RMBS [Member]
Concentration of Credit Risk (Fixed Maturity Securities) - RMBS
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)	20,539	22,430
% of Total	47.20%	50.10%
Portion rated NAIC 1 [Member] | RMBS [Member]
Concentration of Credit Risk (Fixed Maturity Securities) - RMBS
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)	37,484	38,984
% of Total	86.10%	87.10%
Alternative residential mortgage loans [Member] | RMBS [Member]
Concentration of Credit Risk (Fixed Maturity Securities) - RMBS
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)	4,760	4,221
% of Total	10.90%	9.40%
RMBS [Member]
Concentration of Credit Risk (Fixed Maturity Securities) - RMBS
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)	43,550	44,733
% of Total	12.80%	13.80%
RMBS [Member] | Portion rated Aaa/AAA [Member]
Concentration of Credit Risk (Fixed Maturity Securities) - RMBS
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)	$ 34,105	$ 36,085
% of Total	78.30%	80.70%
Alternative residential mortgage loans [Member]
Concentration of Credit Risk (Fixed Maturity Securities) - RMBS
% of Total	100.00%	100.00%