Noncash Investing and Financing Activities (Detail) (USD $) In Millions	9 Months Ended
Sep. 30, 2011	Sep. 30, 2010
Transfers:
Portfolio loans to held for sale loans	$ 115	$ 650
Held for sale loans to portfolio loans	17	18
Portfolio loans to OREO	262	532
Held for sale loans to OREO	38	50
Impact of change in accounting principle:
Change In Accounting Principle Net Decrease In Available For Sale Securities		941
Change In Accounting Principle Increase In Portfolio Loans		2,217
Change In Accounting Principle Decrease In Demand Deposits		18
Change In Accounting Principle Increase In Other Short Term Borrowings		122
Change In Accounting Principle Increase In Long Term Debt		1,344
Cash Paid During Period For [Abstract]
Interest	525	726
Income Taxes Paid	$ 45	$ 76

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