Noncash Investing and Financing Activities (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Transfers:
Portfolio loans to held for sale loans	$ 62	$ 143	$ 650
Held for sale loans to portfolio loans	77	32	160
Portfolio loans to OREO	272	342	662
Held for sale loans to OREO	23	43	68
Impact of change in accounting principle:
Decrease in available-for-sale securities, net			941
Increase in portfolio loans			2,217
Decrease in demand deposits			18
Increase in other short-term borrowings			122
Increase in long-term debt			1,344
Cash Payments:
Interest	524	658	920
Income Taxes Paid	$ 383	$ 102	$ 79

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Value of real estate transferred in noncash transactions from held for sale to other real estate owned during the reporting period.

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The amount of cash paid during the current period to foreign, federal, state, and local authorities as taxes on income.

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