Derivative Instruments (Total Fair Value Of Company's Derivative Assets And Liabilities By Instrument And Balance Sheet Location, Before Counterparty Netting) (Details) (USD $) In Millions, unless otherwise specified	Mar. 31, 2012		Dec. 31, 2011
Derivative [Line Items]
Derivative Instruments, Designated as hedging instruments	$ 149		$ 241
Derivative Instruments, Not designated as hedging instruments	77,324		87,616
Derivative assets, Total derivatives	539		552
Derivative liabilities, Total derivatives	(5,700)		(6,100)
Notional Amount Outstanding, Total derivatives	77,473		87,857
Interest Rate Swaps [Member]
Derivative [Line Items]
Derivative Instruments, Designated as hedging instruments	149		241
Derivative Instruments, Not designated as hedging instruments	2,649		2,706
Insured Credit Default Swaps [Member]
Derivative [Line Items]
Derivative Instruments, Not designated as hedging instruments	60,412		66,851
Insured Swaps [Member]
Derivative [Line Items]
Derivative Instruments, Not designated as hedging instruments	6,746		7,156
Non-Insured Credit Default Swaps [Member]
Derivative [Line Items]
Derivative Instruments, Not designated as hedging instruments	30		30
Non-Insured Credit Default Swaps-VIE [Member]
Derivative [Line Items]
Derivative Instruments, Not designated as hedging instruments	1,272		1,272
Interest Rate Swaps-VIE [Member]
Derivative [Line Items]
Derivative Instruments, Not designated as hedging instruments	4,791		4,878
Interest Rate Swaps-Embedded [Member]
Derivative [Line Items]
Derivative Instruments, Not designated as hedging instruments	489		480
Currency Swaps [Member]
Derivative [Line Items]
Derivative Instruments, Not designated as hedging instruments	40		62
Currency Swaps-VIE [Member]
Derivative [Line Items]
Derivative Instruments, Not designated as hedging instruments	119		123
All Other [Member]
Derivative [Line Items]
Derivative Instruments, Not designated as hedging instruments	195		3,465
All Other-VIE [Member]
Derivative [Line Items]
Derivative Instruments, Not designated as hedging instruments	460		472
All Other-Embedded [Member]
Derivative [Line Items]
Derivative Instruments, Not designated as hedging instruments	121		121
Derivative Assets [Member]
Derivative [Line Items]
Derivative Assets, Designated, Fair Value	8	[1]	10	[1]
Derivative Assets, Not designated, Fair Value	531	[1]	542	[1]
Derivative assets, Total derivatives	539	[1]	552	[1]
Derivative Assets [Member] | Interest Rate Swaps [Member]
Derivative [Line Items]
Derivative Assets, Designated, Fair Value	8	[1]	10	[1]
Derivative Assets, Not designated, Fair Value	70	[1]	84	[1]
Derivative Assets [Member] | Insured Credit Default Swaps [Member]
Derivative [Line Items]
Derivative Assets, Not designated, Fair Value	10	[1]
Derivative Assets [Member] | Non-Insured Credit Default Swaps [Member]
Derivative [Line Items]
Derivative Assets, Not designated, Fair Value			1	[1]
Derivative Liabilities [Member]
Derivative [Line Items]
Derivative Liabilities, Designated, Fair Value	(15)	[1]	(44)	[1]
Derivative Liabilities, Not designated, Fair Value	(5,717)	[1]	(6,064)	[1]
Derivative liabilities, Total derivatives	(5,732)	[1]	(6,108)	[1]
Derivative Liabilities [Member] | Interest Rate Swaps [Member]
Derivative [Line Items]
Derivative Liabilities, Designated, Fair Value	(15)	[1]	(44)	[1]
Derivative Liabilities, Not designated, Fair Value	(375)	[1]	(401)	[1]
Derivative Liabilities [Member] | Insured Credit Default Swaps [Member]
Derivative [Line Items]
Derivative Liabilities, Not designated, Fair Value	(4,416)	[1]	(4,708)	[1]
Derivative Liabilities [Member] | Insured Swaps [Member]
Derivative [Line Items]
Derivative Liabilities, Not designated, Fair Value	(9)	[1]	(9)	[1]
Derivative Liabilities [Member] | Currency Swaps [Member]
Derivative [Line Items]
Derivative Liabilities, Not designated, Fair Value	(3)	[1]	(4)	[1]
Derivative Liabilities [Member] | All Other [Member]
Derivative [Line Items]
Derivative Liabilities, Not designated, Fair Value	(88)	[1]	(91)	[1]
Medium-Term Notes [Member] | Interest Rate Swaps-Embedded [Member]
Derivative [Line Items]
Derivative Assets, Not designated, Fair Value	6	[1]	7	[1]
Derivative Liabilities, Not designated, Fair Value	(22)	[1]	(14)	[1]
Derivative Assets-VIE [Member] | Non-Insured Credit Default Swaps-VIE [Member]
Derivative [Line Items]
Derivative Assets, Not designated, Fair Value	443	[1]	447	[1]
Derivative Assets-VIE [Member] | All Other-VIE [Member]
Derivative [Line Items]
Derivative Assets, Not designated, Fair Value	2	[1]	3	[1]
Derivative Liabilities-VIE [Member] | Non-Insured Credit Default Swaps-VIE [Member]
Derivative [Line Items]
Derivative Liabilities, Not designated, Fair Value	(525)	[1]	(527)	[1]
Derivative Liabilities-VIE [Member] | Interest Rate Swaps-VIE [Member]
Derivative [Line Items]
Derivative Liabilities, Not designated, Fair Value	(259)	[1]	(281)	[1]
Derivative Liabilities-VIE [Member] | Currency Swaps-VIE [Member]
Derivative [Line Items]
Derivative Liabilities, Not designated, Fair Value	(19)	[1]	(17)	[1]
Derivative Liabilities, Other Investments [Member] | All Other-Embedded [Member]
Derivative [Line Items]
Derivative Liabilities, Not designated, Fair Value	$ (1)	[1]	$ (12)	[1]

[1] In accordance with the accounting guidance for derivative instruments and hedging activities, the balance sheet location of the Company's embedded derivative instruments is determined by the location of the related host contract.