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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- Definition

Loans Held For Investment Sold

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- Definition

Maximum Exposure to Loss

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Percentage Of Accruing Troubled Debt Restructurings, Current

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- Definition

Percentage Of Loan Portfolio

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- Definition

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.

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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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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 $)	6 Months Ended
Loans - Additional Information (Detail) (USD $)	Jun. 30, 2011	Jun. 30, 2010	Dec. 31, 2010
Accounts, Notes, Loans and Financing Receivable [Line Items]
Value of loans transferred from LHFI to LHFS	$ 198,000,000	$ 238,000,000
Loans held for investment sold	277,000,000
Gain on sale of loans held for investment	10,000,000
Commitments to lend additional funds to debtors owing receivables	21,000,000		15,000,000
Cross-Border Outstanding Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Concentration of credit risk, maximum exposure	383,000,000		446,000,000
Residential Mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Concentration of credit risk, maximum exposure	45,000,000,000		46,500,000,000
Concentration of credit risk, maximum exposure, percentage of total loans	39.00%		40.00%
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	16,700,000,000		17,600,000,000
Commitments to Extend Credit
Accounts, Notes, Loans and Financing Receivable [Line Items]
Concentration of credit risk, maximum exposure	13,200,000,000		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	12,100,000,000		13,200,000,000
Interest only period	10		10
Amortizing Loans \| Risk Level, High
Accounts, Notes, Loans and Financing Receivable [Line Items]
Concentration of credit risk, maximum exposure	1,900,000,000		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	86.00%		85.00%
Guaranteed Student Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Student loan portfolio percentage	77.00%		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