Derivatives (Fair Value Hedges) (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)
Net Derivatives Gains (Losses) Recognized for Hedged Items	0	(3)	(15)	(25)
Ineffectiveness Recognized in Net Derivatives Gains (Losses)	(1)	(1)	(4)	(11)
Interest rate swaps [Member] | Fixed maturity securities [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Net Derivatives Gains (Losses) Recognized for Derivatives	(1)	(3)	6	(5)
Net Derivatives Gains (Losses) Recognized for Hedged Items	(1)	(2)	7	(3)
Ineffectiveness Recognized in Net Derivatives Gains (Losses)	0	(1)	(1)	(2)
Interest rate swaps [Member] | Policyholder account balances [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Net Derivatives Gains (Losses) Recognized for Derivatives	(6)	(4)	(24)	(2)
Net Derivatives Gains (Losses) Recognized for Hedged Items	(6)	(4)	(22)	(1)
Ineffectiveness Recognized in Net Derivatives Gains (Losses)	0	0	(2)	(1)
Foreign currency swaps [Member] | Foreign-denominated policyholder account balances [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Net Derivatives Gains (Losses) Recognized for Derivatives	6	3	(1)	(29)
Net Derivatives Gains (Losses) Recognized for Hedged Items	7	3	0	(21)
Ineffectiveness Recognized in Net Derivatives Gains (Losses)	$ (1)	$ 0	$ (1)	$ (8)