Derivatives (Gains Losses Recognized in Income Not Designated or Qualifying) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Derivative Instruments, Gain (Loss) [Line Items]
Net Derivatives Gains (Losses) Recognized for Derivatives	$ (1)	$ (4)	$ (19)	$ (36)
Derivatives Not Designated or Not Qualifying as Hedging Instruments [Member] | Net Derivative Gain (Loss) [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Net Derivatives Gains (Losses) Recognized for Derivatives	(192)	(213)	(815)	(297)
Derivatives Not Designated or Not Qualifying as Hedging Instruments [Member] | Net Derivative Gain (Loss) [Member] | Interest rate [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Net Derivatives Gains (Losses) Recognized for Derivatives	(47)	(84)	(450)	33
Derivatives Not Designated or Not Qualifying as Hedging Instruments [Member] | Net Derivative Gain (Loss) [Member] | Foreign currency [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Net Derivatives Gains (Losses) Recognized for Derivatives	(30)	(11)	(14)	(3)
Derivatives Not Designated or Not Qualifying as Hedging Instruments [Member] | Net Derivative Gain (Loss) [Member] | Credit default swaps - purchased [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Net Derivatives Gains (Losses) Recognized for Derivatives	0	(2)	0	(10)
Derivatives Not Designated or Not Qualifying as Hedging Instruments [Member] | Net Derivative Gain (Loss) [Member] | Credit default swaps - written [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Net Derivatives Gains (Losses) Recognized for Derivatives	10	22	17	36
Derivatives Not Designated or Not Qualifying as Hedging Instruments [Member] | Net Derivative Gain (Loss) [Member] | Equity market [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Net Derivatives Gains (Losses) Recognized for Derivatives	(125)	(138)	(368)	(353)
Derivatives Not Designated or Not Qualifying as Hedging Instruments [Member] | Net Investment Gains (Losses) [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Net Derivatives Gains (Losses) Recognized for Derivatives	(3)	(1)	(6)	(3)
Derivatives Not Designated or Not Qualifying as Hedging Instruments [Member] | Net Investment Gains (Losses) [Member] | Interest rate [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Net Derivatives Gains (Losses) Recognized for Derivatives	0	0	0	0
Derivatives Not Designated or Not Qualifying as Hedging Instruments [Member] | Net Investment Gains (Losses) [Member] | Foreign currency [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Net Derivatives Gains (Losses) Recognized for Derivatives	0	0	0	0
Derivatives Not Designated or Not Qualifying as Hedging Instruments [Member] | Net Investment Gains (Losses) [Member] | Credit default swaps - purchased [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Net Derivatives Gains (Losses) Recognized for Derivatives	0	0	0	0
Derivatives Not Designated or Not Qualifying as Hedging Instruments [Member] | Net Investment Gains (Losses) [Member] | Credit default swaps - written [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Net Derivatives Gains (Losses) Recognized for Derivatives	0	0	0	0
Derivatives Not Designated or Not Qualifying as Hedging Instruments [Member] | Net Investment Gains (Losses) [Member] | Equity market [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Net Derivatives Gains (Losses) Recognized for Derivatives	(3)	(1)	(6)	(3)
Derivatives Not Designated or Not Qualifying as Hedging Instruments [Member] | Policyholder Benefits and Claims [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Net Derivatives Gains (Losses) Recognized for Derivatives	(18)	(24)	(76)	(47)
Derivatives Not Designated or Not Qualifying as Hedging Instruments [Member] | Policyholder Benefits and Claims [Member] | Interest rate [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Net Derivatives Gains (Losses) Recognized for Derivatives	(3)	0	(16)	0
Derivatives Not Designated or Not Qualifying as Hedging Instruments [Member] | Policyholder Benefits and Claims [Member] | Foreign currency [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Net Derivatives Gains (Losses) Recognized for Derivatives	0	0	0	0
Derivatives Not Designated or Not Qualifying as Hedging Instruments [Member] | Policyholder Benefits and Claims [Member] | Credit default swaps - purchased [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Net Derivatives Gains (Losses) Recognized for Derivatives	0	0	0	0
Derivatives Not Designated or Not Qualifying as Hedging Instruments [Member] | Policyholder Benefits and Claims [Member] | Credit default swaps - written [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Net Derivatives Gains (Losses) Recognized for Derivatives	0	0	0	0
Derivatives Not Designated or Not Qualifying as Hedging Instruments [Member] | Policyholder Benefits and Claims [Member] | Equity market [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Net Derivatives Gains (Losses) Recognized for Derivatives	$ (15)	$ (24)	$ (60)	$ (47)