Estimated Amortization Expense (Detail) (USD $) In Millions	9 Months Ended
Sep. 30, 2011
Expected Amortization Expense [Line Items]
Remainder of 2011	$ 74
2012	248
2013	189
2014	146
2015	114
Mortgage Servicing Rights
Expected Amortization Expense [Line Items]
Remainder of 2011	70
2012	235
2013	181
2014	142
2015	112
Other Intangible Assets
Expected Amortization Expense [Line Items]
Remainder of 2011	4
2012	13
2013	8
2014	4
2015	$ 2

Expected Amortization Expense [Line Items]

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- Definition

The amount of amortization expense expected to be recognized during the remainder of the current fiscal year.

+ Details

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- Definition

The amount of amortization expense expected to be recognized during year five of the five succeeding fiscal years.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 142

-Paragraph 45

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 50

-Paragraph 2

-Subparagraph (a)(3)

-URI http://asc.fasb.org/extlink&oid=6905858&loc=d3e16323-109275

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- Definition

The amount of amortization expense expected to be recognized during year four of the five succeeding fiscal years.

+ References

+ Details

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- Definition

The amount of amortization expense expected to be recognized during year three of the five succeeding fiscal years.

+ References

+ Details

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- Definition

The amount of amortization expense expected to be recognized during year two of the five succeeding fiscal years.

+ References

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