Quantitative Effect of Adoption of new accounting standard related to TDRs

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Government Guarantee Percent

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Interest Only Period

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Loans and Leases Receivable, Individually Evaluated for Impairment

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Loans Held For Investment Sold

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Maximum Exposure to Loss

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Percentage Of Accruing Troubled Debt Restructurings, Current

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Percentage Of Loan Portfolio

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

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-Publisher FASB

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The amount of the outstanding recorded investment related to financing receivables that have been modified by troubled debt restructurings.

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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.

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Reflects the unfunded portion of contractual agreements to lend funds to borrowers for loans whose terms have been modified by troubled debt restructuring.

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

-Publisher FASB

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Value of loans and leases held in the entity's portfolio transferred to loans and leases held-for-sale in noncash transactions.

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Loans - Additional Information (Detail) (USD $)	9 Months Ended		12 Months Ended
Loans - Additional Information (Detail) (USD $)	Sep. 30, 2011 contracts years	Sep. 30, 2010	Dec. 31, 2010 years	Jul. 02, 2011
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivables, New Accounting Standard, Restructurings, Quantitative Effect of Adoption				$ 93,000,000
Value of loans transferred from LHFI to LHFS	657,000,000	296,000,000
Loans held for investment sold			479,000,000
Gain on sale of loans held for investment			20,000,000
Commitments to lend additional funds to debtors owing receivables	12,000,000		15,000,000
Concentration of credit risk, maximum exposure, percentage of total loans	38.00%
Interest only period	10		10
Cross-Border Outstanding Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Concentration of credit risk, maximum exposure	418,000,000		446,000,000
Residential Mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Concentration of credit risk, maximum exposure, percentage of total loans			40.00%
Concentration of credit risk, maximum exposure	45,000,000,000		46,500,000,000
Government guaranteed	10.00%		10.00%
Residential Mortgage \| Risk Level, High
Accounts, Notes, Loans and Financing Receivable [Line Items]
Concentration of credit risk, maximum exposure	16,400,000,000		17,600,000,000
Commitments to Extend Credit
Accounts, Notes, Loans and Financing Receivable [Line Items]
Concentration of credit risk, maximum exposure	13,000,000,000		13,600,000,000
Loan Origination Commitments
Accounts, Notes, Loans and Financing Receivable [Line Items]
Concentration of credit risk, maximum exposure	7,200,000,000		9,200,000,000
Interest Only Loans \| Risk Level, High
Accounts, Notes, Loans and Financing Receivable [Line Items]
Concentration of credit risk, maximum exposure	11,700,000,000		13,200,000,000
Amortizing Loans \| Risk Level, High
Accounts, Notes, Loans and Financing Receivable [Line Items]
Concentration of credit risk, maximum exposure	1,800,000,000		2,000,000,000
Accrual Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accruing TDRs included in impaired loan balances	2,600,000,000		2,500,000,000
Accruing TDRs current	93.00%		85.00%
Guaranteed Student Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Student loan portfolio percentage	80.00%		77.00%
Lower Limit
Accounts, Notes, Loans and Financing Receivable [Line Items]
Minimum amount of modified loan in a TDR to evaluate individually for impairment	$ 4,000,000