Summary of the Balance Sheet Classification of the Derivative Fair Value Amounts, as well as the Gross Asset and Liability Fair Value Amounts (Detail) (USD $) In Millions	Sep. 30, 2011	Dec. 31, 2010
Derivatives, Fair Value [Line Items]
Net Derivatives Notional Amount	$ 5,557	$ 6,174
Net Derivatives Fair Value	(201)	(177)
Asset Derivatives Fair Value	407	564
Liability Derivatives Fair Value	(608)	(741)
Cash flow hedges
Derivatives, Fair Value [Line Items]
Net Derivatives Notional Amount	147	860
Net Derivatives Fair Value	31	168
Asset Derivatives Fair Value	31	180
Liability Derivatives Fair Value	0	(12)
Cash flow hedges \| Interest rate swaps
Derivatives, Fair Value [Line Items]
Net Derivatives Notional Amount	72	245
Net Derivatives Fair Value	0	(2)
Asset Derivatives Fair Value	0	0
Liability Derivatives Fair Value	0	(2)
Cash flow hedges \| Foreign currency swaps
Derivatives, Fair Value [Line Items]
Net Derivatives Notional Amount	75	615
Net Derivatives Fair Value	31	170
Asset Derivatives Fair Value	31	180
Liability Derivatives Fair Value	0	(10)
Non-qualifying strategies
Derivatives, Fair Value [Line Items]
Net Derivatives Notional Amount	5,410	5,314
Net Derivatives Fair Value	(232)	(345)
Asset Derivatives Fair Value	376	384
Liability Derivatives Fair Value	(608)	(729)
Non-qualifying strategies \| Interest rate swaps
Derivatives, Fair Value [Line Items]
Net Derivatives Notional Amount	427	743
Net Derivatives Fair Value	59	56
Asset Derivatives Fair Value	99	124
Liability Derivatives Fair Value	(40)	(68)
Non-qualifying strategies \| Foreign currency swaps
Derivatives, Fair Value [Line Items]
Net Derivatives Notional Amount	4,556	3,815
Net Derivatives Fair Value	(97)	(58)
Asset Derivatives Fair Value	277	260
Liability Derivatives Fair Value	(374)	(318)
Non-qualifying strategies \| Credit default swaps
Derivatives, Fair Value [Line Items]
Net Derivatives Notional Amount	427	756
Net Derivatives Fair Value	(194)	(343)
Asset Derivatives Fair Value	0	0
Liability Derivatives Fair Value	(194)	(343)
Cash flow hedges and non-qualifying strategies
Derivatives, Fair Value [Line Items]
Net Derivatives Notional Amount	5,557	6,174
Net Derivatives Fair Value	(201)	(177)
Asset Derivatives Fair Value	407	564
Liability Derivatives Fair Value	(608)	(741)
Other assets
Derivatives, Fair Value [Line Items]
Net Derivatives Notional Amount	1,666	2,364
Net Derivatives Fair Value	407	564
Asset Derivatives Fair Value	407	564
Liability Derivatives Fair Value	0	0
Other Liabilities
Derivatives, Fair Value [Line Items]
Net Derivatives Notional Amount	3,891	3,810
Net Derivatives Fair Value	(608)	(741)
Asset Derivatives Fair Value	0	0
Liability Derivatives Fair Value	$ (608)	$ (741)

Fair value of derivative asset, presented on a gross basis even when the derivative instrument is subject to master netting arrangements and qualifies for net presentation in the statement of financial position.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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Fair value of derivative liability, presented on a gross basis even when the derivative instrument is subject to master netting arrangements and qualifies for net presentation in the statement of financial position.

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Fair value as of the balance sheet date of the assets less the liabilities of a derivative or group of derivatives.

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Aggregate notional amount of all derivatives. The notional amount relates to a number of currency units, shares, bushels, pounds, or other units specified in a derivative instrument.

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