Change in Fair Value of Financial Instruments for which the FVO has been Elected (Parenthetical) (Detail) (USD $) In Millions	12 Months Ended	3 Months Ended	9 Months Ended	3 Months Ended	9 Months Ended
Dec. 31, 2010	Sep. 30, 2011 Loans Held-for-Sale Mortgage Production Income	Sep. 30, 2010 Loans Held-for-Sale Mortgage Production Income	Sep. 30, 2011 Loans Held-for-Sale Mortgage Production Income	Sep. 30, 2010 Loans Held-for-Sale Mortgage Production Income	Sep. 30, 2011 Mortgage Servicing Rights Mortgage Production Income	Sep. 30, 2010 Mortgage Servicing Rights Mortgage Production Income	Sep. 30, 2011 Mortgage Servicing Rights Mortgage Production Income	Sep. 30, 2010 Mortgage Servicing Rights Mortgage Production Income
Income recognized upon the sale of loans	$ 20	$ 46	$ 57	$ 178	$ 184	$ 1	$ 7	$ 5	$ 14

The net gain (loss) resulting from a sale of loans, including adjustments to record loans classified as held-for-sale at the lower-of-cost-or-market and fair value adjustments to loan held for investment purposes.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6943989&loc=d3e3602-108585

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 225

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-04.13(h))

-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 225

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-04.3(a))

-URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913

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