Fair Value Measurements - Financial Instruments Excluding Guaranteed Living Benefits (Details 2) (USD $) In Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Fair Value, Option, Quantitative Disclosures [Line Items]
Changes in fair value of assets and liabilities accounted for using the fair value option	$ (3)	$ 35	$ 36	$ 28
Fixed Maturities, FVO [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Changes in fair value of assets and liabilities accounted for using the fair value option
ABS [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Changes in fair value of assets and liabilities accounted for using the fair value option		1		3
CDOs [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Changes in fair value of assets and liabilities accounted for using the fair value option	(64)	44	(43)	44
Corporate [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Changes in fair value of assets and liabilities accounted for using the fair value option	(3)	4	11
Foreign government/government agencies [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Changes in fair value of assets and liabilities accounted for using the fair value option	33		44
Credit-linked notes [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Changes in fair value of assets and liabilities accounted for using the fair value option	$ 31	$ (14)	$ 24	$ (19)