Derivatives (Details 3) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Gains/(losses) for derivatives not Designated as hedging instrument
Net Derivatives Gains (Losses) Recognized for Derivatives	$ (135)	$ 981	$ 149
Derivatives Not Designated or Not Qualifying as Hedging Instruments [Member] | Net Derivative Gains (Losses) [Member]
Gains/(losses) for derivatives not Designated as hedging instrument
Net Derivatives Gains (Losses) Recognized for Derivatives	(3,660)	5,636	139
Derivatives Not Designated or Not Qualifying as Hedging Instruments [Member] | Net Derivative Gains (Losses) [Member] | Interest rate [Member]
Gains/(losses) for derivatives not Designated as hedging instrument
Net Derivatives Gains (Losses) Recognized for Derivatives	(296)	3,940	691
Derivatives Not Designated or Not Qualifying as Hedging Instruments [Member] | Net Derivative Gains (Losses) [Member] | Foreign currency [Member]
Gains/(losses) for derivatives not Designated as hedging instrument
Net Derivatives Gains (Losses) Recognized for Derivatives	(660)	343	196
Derivatives Not Designated or Not Qualifying as Hedging Instruments [Member] | Net Derivative Gains (Losses) [Member] | Credit [Member]
Gains/(losses) for derivatives not Designated as hedging instrument
Net Derivatives Gains (Losses) Recognized for Derivatives	(148)	175	34
Derivatives Not Designated or Not Qualifying as Hedging Instruments [Member] | Net Derivative Gains (Losses) [Member] | Equity market [Member]
Gains/(losses) for derivatives not Designated as hedging instrument
Net Derivatives Gains (Losses) Recognized for Derivatives	(2,556)	1,178	(782)
Derivatives Not Designated or Not Qualifying as Hedging Instruments [Member] | Net Investment Gains (Losses) [Member]
Gains/(losses) for derivatives not Designated as hedging instrument
Net Derivatives Gains (Losses) Recognized for Derivatives	(23)	(40)	11
Derivatives Not Designated or Not Qualifying as Hedging Instruments [Member] | Net Investment Gains (Losses) [Member] | Interest rate [Member]
Gains/(losses) for derivatives not Designated as hedging instrument
Net Derivatives Gains (Losses) Recognized for Derivatives	0	(1)	0
Derivatives Not Designated or Not Qualifying as Hedging Instruments [Member] | Net Investment Gains (Losses) [Member] | Foreign currency [Member]
Gains/(losses) for derivatives not Designated as hedging instrument
Net Derivatives Gains (Losses) Recognized for Derivatives	0	(9)	54
Derivatives Not Designated or Not Qualifying as Hedging Instruments [Member] | Net Investment Gains (Losses) [Member] | Credit [Member]
Gains/(losses) for derivatives not Designated as hedging instrument
Net Derivatives Gains (Losses) Recognized for Derivatives	(14)	5	(2)
Derivatives Not Designated or Not Qualifying as Hedging Instruments [Member] | Net Investment Gains (Losses) [Member] | Equity market [Member]
Gains/(losses) for derivatives not Designated as hedging instrument
Net Derivatives Gains (Losses) Recognized for Derivatives	(9)	(35)	(41)
Derivatives Not Designated or Not Qualifying as Hedging Instruments [Member] | Policyholder Benefits and Claims [Member]
Gains/(losses) for derivatives not Designated as hedging instrument
Net Derivatives Gains (Losses) Recognized for Derivatives	(419)	(87)	(275)
Derivatives Not Designated or Not Qualifying as Hedging Instruments [Member] | Policyholder Benefits and Claims [Member] | Interest rate [Member]
Gains/(losses) for derivatives not Designated as hedging instrument
Net Derivatives Gains (Losses) Recognized for Derivatives	0	0	39
Derivatives Not Designated or Not Qualifying as Hedging Instruments [Member] | Policyholder Benefits and Claims [Member] | Foreign currency [Member]
Gains/(losses) for derivatives not Designated as hedging instrument
Net Derivatives Gains (Losses) Recognized for Derivatives	0	0	0
Derivatives Not Designated or Not Qualifying as Hedging Instruments [Member] | Policyholder Benefits and Claims [Member] | Credit [Member]
Gains/(losses) for derivatives not Designated as hedging instrument
Net Derivatives Gains (Losses) Recognized for Derivatives	0	0	0
Derivatives Not Designated or Not Qualifying as Hedging Instruments [Member] | Policyholder Benefits and Claims [Member] | Equity market [Member]
Gains/(losses) for derivatives not Designated as hedging instrument
Net Derivatives Gains (Losses) Recognized for Derivatives	(419)	(87)	(314)
Derivatives Not Designated or Not Qualifying as Hedging Instruments [Member] | Other Revenues [Member]
Gains/(losses) for derivatives not Designated as hedging instrument
Net Derivatives Gains (Losses) Recognized for Derivatives	28	236	89
Derivatives Not Designated or Not Qualifying as Hedging Instruments [Member] | Other Revenues [Member] | Interest rate [Member]
Gains/(losses) for derivatives not Designated as hedging instrument
Net Derivatives Gains (Losses) Recognized for Derivatives	28	236	89
Derivatives Not Designated or Not Qualifying as Hedging Instruments [Member] | Other Revenues [Member] | Foreign currency [Member]
Gains/(losses) for derivatives not Designated as hedging instrument
Net Derivatives Gains (Losses) Recognized for Derivatives	0	0	0
Derivatives Not Designated or Not Qualifying as Hedging Instruments [Member] | Other Revenues [Member] | Credit [Member]
Gains/(losses) for derivatives not Designated as hedging instrument
Net Derivatives Gains (Losses) Recognized for Derivatives	0	0	0
Derivatives Not Designated or Not Qualifying as Hedging Instruments [Member] | Other Revenues [Member] | Equity market [Member]
Gains/(losses) for derivatives not Designated as hedging instrument
Net Derivatives Gains (Losses) Recognized for Derivatives	0	0	0
Derivatives Not Designated or Not Qualifying as Hedging Instruments [Member] | Other Expenses [Member]
Gains/(losses) for derivatives not Designated as hedging instrument
Net Derivatives Gains (Losses) Recognized for Derivatives	0	0	(4)
Derivatives Not Designated or Not Qualifying as Hedging Instruments [Member] | Other Expenses [Member] | Interest rate [Member]
Gains/(losses) for derivatives not Designated as hedging instrument
Net Derivatives Gains (Losses) Recognized for Derivatives	0	0	0
Derivatives Not Designated or Not Qualifying as Hedging Instruments [Member] | Other Expenses [Member] | Foreign currency [Member]
Gains/(losses) for derivatives not Designated as hedging instrument
Net Derivatives Gains (Losses) Recognized for Derivatives	0	0	(4)
Derivatives Not Designated or Not Qualifying as Hedging Instruments [Member] | Other Expenses [Member] | Credit [Member]
Gains/(losses) for derivatives not Designated as hedging instrument
Net Derivatives Gains (Losses) Recognized for Derivatives	0	0	0
Derivatives Not Designated or Not Qualifying as Hedging Instruments [Member] | Other Expenses [Member] | Equity market [Member]
Gains/(losses) for derivatives not Designated as hedging instrument
Net Derivatives Gains (Losses) Recognized for Derivatives	$ 0	$ 0	$ 0