Amounts Outstanding in Selected Loan Categories (Detail) (USD $) In Millions	Sep. 30, 2011	Dec. 31, 2010
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans and Leases	$ 28,691.4	$ 28,132.0
Allowance for Credit Losses Assigned to Loans and Leases	(298.3)	(319.6)
Net Loans and Leases	28,393.1	27,812.4
Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial and Institutional	6,458.0	5,914.5
Commercial Real Estate	2,958.2	3,242.4
Lease Financing, net	1,014.1	1,063.7
Non-U.S.	1,315.2	1,046.2
Other	473.8	346.6
Total Loans and Leases	12,219.3	11,613.4
Allowance for Credit Losses Assigned to Loans and Leases	(186.4)	(220.7)
Personal
Accounts, Notes, Loans and Financing Receivable [Line Items]
Residential Real Estate	10,772.4	10,854.9
Private Client	5,427.7	5,423.7
Other	272.0	240.0
Total Loans and Leases	16,472.1	16,518.6
Allowance for Credit Losses Assigned to Loans and Leases	$ (111.9)	$ (98.9)

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Loans and Leases Receivable, Residential, Real Estate

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The total gross amount of commercial loans (money lent to commercial entities rather than consumers) made in the form of direct financing leases where the reporting entity (lessor) only recognizes interest revenue from the lease. It also includes the amount of lease financing arising from involvement with leveraged lease transactions where the Entity is in the position of long-term creditor.

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The allowance for loan and lease losses represents the reserve to cover probable credit losses related to specifically identified loans and leases, as well as probable credit losses inherent in the remainder of the loan portfolio as of the balance sheet date. For banks, include currently required allocated transfer risk reserves. Include carryover of or adjustments to the allowance for loan losses in connection with business combinations determined to be appropriate.

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Reflects the net carrying amount of foreign loans and leases held in portfolio, after deducting deferred income, but before deducting the allowance for losses on foreign loans and leases.

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Reflects the aggregate gross carrying amount of all categories of loans and leases held in portfolio, after deducting deferred income, but before deducting the allowance for losses on loans and leases.

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Reflects the aggregate carrying amount of all categories of loans and leases held in portfolio, net of unearned income and the allowance for losses on loans and leases.

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The gross amount of other loans and leases not otherwise specified in the taxonomy.

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Reflects the sum of the gross carrying amounts of unpaid loans issued to businesses to provide financing for cash needs, financial asset purchases, or farm-related purposes. Includes all loans not included in another category. This category includes, but is not limited to, loans to real estate investment trusts; mortgage companies, banks, and other financial institutions; loans for carrying securities; and loans for agricultural purposes. This element does not include loans secured primarily by developed real estate.

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