Loans, Allowance for Loan Losses, and Credit Quality (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2012	Dec. 31, 2011
Loan composition
Commercial and industrial	$ 3,719,016	$ 3,724,736
Commercial real estate - owner occupied	1,074,755	1,086,829
Lease financing	61,208	58,194
Commercial and business lending	4,854,979	4,869,759
Commercial real estate - investor	2,664,251	2,563,767
Real estate construction	565,953	584,046
Commercial real estate lending	3,230,204	3,147,813
Total commercial	8,085,183	8,017,572
Home equity	2,501,770	2,504,704
Installment	537,628	557,782
Total retail	3,039,398	3,062,486
Residential mortgage	3,129,144	2,951,013
Total consumer	6,168,542	6,013,499
Total loans	$ 14,253,725	$ 14,031,071

Loans and leases receivable, home equity.

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- Definition

Loans and leases receivable retail.

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No definition available.

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- Definition

Commercial and business lending subtotal

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No definition available.

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- Definition

Commercial Real Estate Investor loans receivable.

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No definition available.

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- Definition

Owner occupied commercial real estate.

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No definition available.

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- Definition

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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-Glossary Leveraged Lease

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Reflects the sum of the gross carrying amounts of the various categories of unpaid commercial loans and leases receivable, primarily issued to businesses. Includes: (1) commercial and industrial loans, consisting of general purpose loans to entities involved in producing, transporting, or merchandising products sold in the course of commerce; (2) agricultural loans consisting of borrowings used to finance major equipment and machinery purchases and expenses, livestock or crop production (including fisheries), and to supplement working capital needs of an entity engaged in farming operations; (3) mortgage loans secured by a [legal] security interest in real property [commercial building or business real property]; (4) obligation in the form of [promissory] notes, used for the funding of construction projects; (5) interbank and other loans to financial institutions for the purpose of liquidity management on the part of the borrower; (6) draws against credit facilities provided to companies involved in mortgage banking activities (warehousing); (7) amounts lent to businesses engaged in international activities (trade financing); (8) lease financings; and (9) loans to governmental entities.

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Reflects the sum of the gross carrying amounts of the various categories of loans made to individuals for personal needs, including mortgage, home equity, vehicles, credit card, installment, and lease financing.

+ References

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- Definition

Reflects the sum of the gross carrying amounts of the various categories of unpaid loans issued to individuals to acquire goods and services. Includes credit card, automobile, boat, student and durable home appliance loans. Also includes the carrying amount of unpaid loans issued to individuals to provide financing in the legal form of a lease agreement which meets the criteria for treating the arrangement as a direct financing lease.

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- Definition

The gross carrying amount of mortgage loans to individuals. This item excludes subordinated loans such as home equity lines of credit.

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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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- Definition

Reflects the gross carrying amount of unpaid loans issued to nonfinancial and nonagricultural businesses for uses other than for real property.

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Reflects the gross carrying amount of unpaid loans that had been issued to businesses to construct a facility. Acquisition, development and construction (ADC) loans are generally issued sequentially and the net proceeds of the latest debt is used by the borrower to pay off the preceding loan. A construction loan ( in the form of a promissory note) is generally expected to be paid off with the net proceeds from permanent financing.

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Reflects the sum of the gross carrying amounts of unpaid loans issued to businesses to acquire, develop, construct, improve, or refinance land or a building. Includes [but is not limited to] commercial mortgage loans, which are secured by a [legal] security interest in real property [commercial building or business real property] which thereby serves as collateral securing repayment of the loan; and construction financing, which is an obligation generally in the form of a [promissory] note, used for the funding of construction projects.

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