Derivative Financial Instruments (Details 5) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2012	Mar. 31, 2011
Derivative Instruments, Gain (Loss) [Line Items]
Net Derivatives Gains (Losses) Recognized for Derivatives	$ (293)	$ (27)
Net Derivatives Gains (Losses) Recognized for Hedged Items	286	20
Ineffectiveness Recognized in Net Derivatives Gains (Losses)	(7)	(7)
Interest rate swaps [Member] | Fixed maturity securities [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Net Derivatives Gains (Losses) Recognized for Derivatives	6	11
Net Derivatives Gains (Losses) Recognized for Hedged Items	(6)	(10)
Ineffectiveness Recognized in Net Derivatives Gains (Losses)	0	1
Interest rate swaps [Member] | Policyholder account balances [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Net Derivatives Gains (Losses) Recognized for Derivatives	(300)	(114)
Net Derivatives Gains (Losses) Recognized for Hedged Items	301	116
Ineffectiveness Recognized in Net Derivatives Gains (Losses)	1	2
Foreign currency swaps [Member] | Foreign-denominated fixed maturity securities [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Net Derivatives Gains (Losses) Recognized for Derivatives	2	(1)
Net Derivatives Gains (Losses) Recognized for Hedged Items	(2)	1
Ineffectiveness Recognized in Net Derivatives Gains (Losses)	0	0
Foreign currency swaps [Member] | Foreign-denominated policyholder account balances [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Net Derivatives Gains (Losses) Recognized for Derivatives	57	77
Net Derivatives Gains (Losses) Recognized for Hedged Items	(63)	(87)
Ineffectiveness Recognized in Net Derivatives Gains (Losses)	(6)	(10)
Foreign currency forwards [Member] | Foreign-denominated fixed maturity securities [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Net Derivatives Gains (Losses) Recognized for Derivatives	(58)	0
Net Derivatives Gains (Losses) Recognized for Hedged Items	56	0
Ineffectiveness Recognized in Net Derivatives Gains (Losses)	$ (2)	$ 0