Investments and Derivative Instruments (Details 13) (USD $) In Millions, unless otherwise specified	9 Months Ended
	Sep. 30, 2012		Dec. 31, 2011
Derivative [Line Items]
Document Period End Date	Sep. 30, 2012
Macro hedge program
Notional Amount	$ 173,376		$ 141,436
Fair Value	(58)		(458)
International [Member]
Macro hedge program
Notional Amount	62,300		33,000
International Program Hedging Instruments [Member]
Macro hedge program
Notional Amount	67,294		33,726
Fair Value	562		750
Other Credit Derivatives [Member] | International Program Hedging Instruments [Member]
Macro hedge program
Notional Amount	50		0
Fair Value	6		0
Foreign Exchange Forward [Member] | International Program Hedging Instruments [Member]
Macro hedge program
Notional Amount	10,148	[1]	8,622	[1]
Fair Value	14	[1]	446	[1]
Currency options [Member] | International Program Hedging Instruments [Member]
Macro hedge program
Notional Amount	9,708		7,357
Fair Value	166		127
Equity futures [Member] | International Program Hedging Instruments [Member]
Macro hedge program
Notional Amount	4,323		3,835
Fair Value	0		0
Equity options [Member] | International Program Hedging Instruments [Member]
Macro hedge program
Notional Amount	4,751		1,565
Fair Value	51		74
Equity swaps [Member] | International Program Hedging Instruments [Member]
Macro hedge program
Notional Amount	2,588	[2]	392	[2]
Fair Value	34	[2]	(8)	[2]
Interest rate futures [Member] | International Program Hedging Instruments [Member]
Macro hedge program
Notional Amount	727		739
Fair Value	0		0
Interest Rate Swaps and Swaptions [Member] | International Program Hedging Instruments [Member]
Macro hedge program
Notional Amount	34,999		11,216
Fair Value	291		111
Net Hedge Position [Member] | Foreign Exchange Forward [Member] | International Program Hedging Instruments [Member]
Macro hedge program
Notional Amount	1,900		7,200
Net Hedge Position [Member] | Equity swaps [Member] | International Program Hedging Instruments [Member]
Macro hedge program
Notional Amount	800		400
Long Hedge Position [Member] | International [Member]
Macro hedge program
Notional Amount	5,000		700
Long Hedge Position [Member] | Foreign Exchange Forward [Member] | International Program Hedging Instruments [Member]
Macro hedge program
Notional Amount	6,000		7,900
Long Hedge Position [Member] | Equity swaps [Member] | International Program Hedging Instruments [Member]
Macro hedge program
Notional Amount	1,700
Short Hedge Position [Member] | Foreign Exchange Forward [Member] | International Program Hedging Instruments [Member]
Macro hedge program
Notional Amount	4,100		700
Short Hedge Position [Member] | Equity swaps [Member] | International Program Hedging Instruments [Member]
Macro hedge program
Notional Amount	$ 900

[1] As of September 30, 2012 and December 31, 2011 net notional amounts are $1.9 billion and $7.2 billion, respectively, which include $6.0 billion and $7.9 billion, respectively, related to long positions and $4.1 billion and $0.7 billion, respectively, related to short positions.

[2] As of September 30, 2012 the net notional amount is $0.8 billion, which includes $1.7 billion related to long positions and $0.9 billion related to short positions. As of December 31, 2011 the net notional amount of $0.4 billion related to long positions only.