Commitments, Contingencies, And Guarantees (Balance Sheet Locations, Fair Values In An Asset Or (Liability) Position, And Notional Values/Payment Provisions Of Derivative Instruments) (Details) (USD $) In Millions, unless otherwise specified	Mar. 31, 2012		Dec. 31, 2011
Investment And Embedded Derivative Instruments [Member]
Derivatives, Fair Value [Line Items]
Fair Value	$ 466		$ 427
Notional Value/Payment Provision	7,319		12,906
Other Derivative Instruments [Member]
Derivatives, Fair Value [Line Items]
Fair Value	(42)		41
Notional Value/Payment Provision	2,815		1,973
Accounts Payable, Accrued Expenses, And Other Liabilities [Member] | Foreign Currency Forward Contracts [Member]
Derivatives, Fair Value [Line Items]
Fair Value	(2)		7
Notional Value/Payment Provision	681		674
Accounts Payable, Accrued Expenses, And Other Liabilities [Member] | Futures Contracts On Money Market Instruments [Member]
Derivatives, Fair Value [Line Items]
Fair Value	1		7
Notional Value/Payment Provision	2,077		10,476
Accounts Payable, Accrued Expenses, And Other Liabilities [Member] | Futures Contracts On Notes And Bonds [Member]
Derivatives, Fair Value [Line Items]
Fair Value	12		(4)
Notional Value/Payment Provision	942		1,055
Accounts Payable, Accrued Expenses, And Other Liabilities [Member] | Options On Money Market Instruments [Member]
Derivatives, Fair Value [Line Items]
Fair Value	1
Notional Value/Payment Provision	3,192		292
Accounts Payable, Accrued Expenses, And Other Liabilities [Member] | Future Contracts On Equities [Member]
Derivatives, Fair Value [Line Items]
Fair Value	(78)	[1]	(16)	[1]
Notional Value/Payment Provision	2,209	[1]	1,367	[1]
Accounts Payable, Accrued Expenses, And Other Liabilities [Member] | Options On Equity Market Indices [Member]
Derivatives, Fair Value [Line Items]
Fair Value	37	[1]	54	[1]
Notional Value/Payment Provision	250	[1]	250	[1]
Accounts Payable, Accrued Expenses, And Other Liabilities [Member] | Credit Default Swaps [Member]
Derivatives, Fair Value [Line Items]
Fair Value	(1)		3
Notional Value/Payment Provision	350		350
Accounts Payable, Accrued Expenses, And Other Liabilities [Member] | Other [Member]
Derivatives, Fair Value [Line Items]
Notional Value/Payment Provision	6		6
Fixed Maturities Available For Sale [Member] | Convertible Bonds [Member]
Derivatives, Fair Value [Line Items]
Fair Value	400		357
Notional Value/Payment Provision	374		353
Fixed Maturities Available For Sale [Member] | To Be Announced Mortgage-Backed Securities [Member]
Derivatives, Fair Value [Line Items]
Fair Value	54		60
Notional Value/Payment Provision	53		56
Accounts Payable Future Policy Benefits [Member] | Guaranteed Living Benefits [Member]
Derivatives, Fair Value [Line Items]
Fair Value	(1,049)	[2]	(1,505)	[2]
Notional Value/Payment Provision	$ 881	[2]	$ 1,378	[2]

[1] Related to GMDB and GLB blocks of business.

[2] Includes both future policy benefits reserves and fair value derivative adjustment. Refer to Note 5 for additional information. Note that the payment provision related to GLB is the net amount at risk. The concept of a notional value does not apply to the GLB reinsurance contracts.