Asset Transfers in Which the Company has Continuing Economic Involvement (Detail) (USD $) In Millions	3 Months Ended	9 Months Ended
Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Cash flows on interests held	$ 11	$ 21	$ 41	$ 54
Servicing or management fees	3	4	11	13
Residential Mortgage
Cash flows on interests held	11	14	39	42
Servicing or management fees	1	1	3	3
Commercial and Corporate Loans
Cash flows on interests held	0	1	1	3
Servicing or management fees	2	3	8	10
Consumer Loan
Cash flows on interests held	0	5	0	8
Servicing or management fees	0	0	0	0
Collateralized Debt Obligations
Cash flows on interests held	0	1	1	1
Servicing or management fees	$ 0	$ 0	$ 0	$ 0

Cash flows between transferor and transferee in payment of service fees in advance, prior to or in contemplation of a securitization, asset-backed financing arrangement, or similar transfer in which the transferor will have continuing involvement with the transferred financial assets underlying the transaction (including, but not limited to, servicing, recourse, and restrictions on transferor's interests in the transferred financial assets).

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 140

-Paragraph 17

-Subparagraph h

-Clause 4

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name FASB Staff Position (FSP)

-Number FAS140-4/FIN46(R)-8

-Paragraph B11

-Subparagraph a

-Clause 3

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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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Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration