Derivative Financial Instruments (Details 4) (USD $) In Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Settlement Payments By Hedge Classification And Income Statement Location
Settlement Payments	$ 469	$ 74	$ 662	$ 451
Derivatives Designated as Hedging Instruments [Member] | Net Investment Income [Member]
Settlement Payments By Hedge Classification And Income Statement Location
Settlement Payments	28	17	70	58
Derivatives Designated as Hedging Instruments [Member] | Interest Credited to Policyholder Account Balance [Member]
Settlement Payments By Hedge Classification And Income Statement Location
Settlement Payments	51	64	169	177
Derivatives Designated as Hedging Instruments [Member] | Other Expenses [Member]
Settlement Payments By Hedge Classification And Income Statement Location
Settlement Payments	(1)	(1)	(2)	(5)
Derivatives Not Designated or Not Qualifying as Hedging Instruments [Member] | Net Investment Income [Member]
Settlement Payments By Hedge Classification And Income Statement Location
Settlement Payments	(2)	(1)	(6)	(3)
Derivatives Not Designated or Not Qualifying as Hedging Instruments [Member] | Net Derivative Gain (Losses) [Member]
Settlement Payments By Hedge Classification And Income Statement Location
Settlement Payments	352	(30)	357	143
Derivatives Not Designated or Not Qualifying as Hedging Instruments [Member] | Other Revenues [Member]
Settlement Payments By Hedge Classification And Income Statement Location
Settlement Payments	22	25	55	81
Derivatives Not Designated or Not Qualifying as Hedging Instruments [Member] | Policyholder Benefit and Claim [Member]
Settlement Payments By Hedge Classification And Income Statement Location
Settlement Payments	$ 19	$ 0	$ 19	$ 0