Loans, Allowance for Loan Losses, and Credit Quality (Details 4) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2011	Dec. 31, 2010
Commercial loans by credit quality indicator
Commercial and industrial	$ 3,724,736	$ 3,049,752
Commercial real estate - owner occupied	1,086,829	1,049,798
Lease financing	58,194	60,254
Commercial and business lending	4,869,759	4,159,804
Commercial real estate - investor	2,563,767	2,339,415
Real estate construction	584,046	553,069
Commercial real estate lending	3,147,813	2,892,484
Total commercial	8,017,572	7,052,288
Pass
Commercial loans by credit quality indicator
Commercial and industrial	3,283,090	2,363,554
Commercial real estate - owner occupied	853,517	743,785
Lease financing	46,570	40,101
Commercial and business lending	4,183,177	3,147,440
Commercial real estate - investor	2,055,124	1,685,554
Real estate construction	494,839	311,810
Commercial real estate lending	2,549,963	1,997,364
Total commercial	6,733,140	5,144,804
Special Mention
Commercial loans by credit quality indicator
Commercial and industrial	209,713	222,089
Commercial real estate - owner occupied	53,090	52,495
Lease financing	822	456
Commercial and business lending	263,625	275,040
Commercial real estate - investor	135,668	175,062
Real estate construction	8,775	32,180
Commercial real estate lending	144,443	207,242
Total commercial	408,068	482,282
Potential Problem
Commercial loans by credit quality indicator
Commercial and industrial	153,306	354,284
Commercial real estate - owner occupied	136,366	193,819
Lease financing	158	2,617
Commercial and business lending	289,830	550,720
Commercial real estate - investor	230,206	298,959
Real estate construction	27,649	91,618
Commercial real estate lending	257,855	390,577
Total commercial	547,685	941,297
Impaired
Commercial loans by credit quality indicator
Commercial and industrial	78,627	109,825
Commercial real estate - owner occupied	43,856	59,699
Lease financing	10,644	17,080
Commercial and business lending	133,127	186,604
Commercial real estate - investor	142,769	179,840
Real estate construction	52,783	117,461
Commercial real estate lending	195,552	297,301
Total commercial	$ 328,679	$ 483,905

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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Reference 4: http://www.xbrl.org/2003/role/presentationRef

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Reference 5: http://www.xbrl.org/2003/role/presentationRef

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-Glossary Leveraged Lease

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+ Details

- Definition

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.

+ References+ Details

- 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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- Definition

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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- Definition

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.

+ References

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+ Details