Loans (Loans) (Details) (USD $) In Thousands, unless otherwise specified	6 Months Ended	12 Months Ended
Jun. 30, 2011	Jun. 30, 2010	Dec. 31, 2010
Total commercial and industrial	$ 3,842,150	$ 3,690,072	$ 3,788,658
Total commercial and industrial percentage	47.60%	45.80%	46.70%
Total commercial real estate	3,157,099	3,194,598	3,202,767
Total commercial real estate percentage	39.10%	39.70%	39.50%
Total consumer real estate	773,069	811,954	798,264
Total consumer real estate percentage	9.60%	10.00%	9.80%
Total real estate	3,930,168	4,006,552	4,001,031
Total real estate percentage	48.70%	49.70%	49.30%
Total consumer and other	314,305	391,130	347,618
Total consumer and other percentage	3.90%	4.80%	4.30%
Unearned discounts	(18,411)	(22,075)	(20,287)
Unearned discounts percentage	(0.20%)	(0.30%)	(0.30%)
Total loans	8,068,212	8,065,679	8,117,020
Total loans percentage	100.00%	100.00%	100.00%
Commercial And Industrial [Member] \| Commercial [Member]
Total commercial and industrial	3,510,738	3,368,349	3,479,349
Total commercial and industrial percentage	43.50%	41.80%	42.90%
Commercial And Industrial [Member] \| Leases [Member]
Total commercial and industrial	184,991	193,107	186,443
Total commercial and industrial percentage	2.30%	2.40%	2.30%
Commercial And Industrial [Member] \| Asset-Based [Member]
Total commercial and industrial	146,421	128,616	122,866
Total commercial and industrial percentage	1.80%	1.60%	1.50%
Commercial Real Estate [Member]
Commercial mortgages	2,403,350	2,377,162	2,374,542
Commercial mortgages percentage	29.80%	29.50%	29.30%
Construction	533,132	585,668	593,273
Construction percentage	6.60%	7.30%	7.30%
Land	220,617	231,768	234,952
Land percentage	2.70%	2.90%	2.90%
Consumer Real Estate [Member]
Home equity loans	276,869	274,129	275,806
Home equity loans percentage	3.40%	3.40%	3.40%
Home equity lines of credit	189,356	175,753	186,465
Home equity lines of credit percentage	2.40%	2.10%	2.30%
1-4 family residential mortgages	49,849	63,220	57,877
1-4 family residential mortgages percentage	0.60%	0.80%	0.70%
Construction	17,952	28,175	23,565
Construction percentage	0.20%	0.30%	0.30%
Other	239,043	270,677	254,551
Other percentage	3.00%	3.40%	3.10%
Total loans	773,069
Consumer And Other [Member]
Consumer installment	298,327	340,719	319,384
Consumer installment percentage	3.70%	4.20%	3.90%
Other	15,978	50,411	28,234
Other percentage	0.20%	0.60%	0.40%
Total loans	$ 314,305

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Loans and Leases Receivable, Total Real Estate

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Loans Receivable, Commercial Real Estate, Land

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One To Four Family Residential Mortgages

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Percent of Commercial and Industrial to Total Loans

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Percent of Commercial Real Estate Construction Loans to Total Loans

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Percent of Commercial Real Estate Land Loans to Total Loans

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Percent of Commercial Real Estate Mortgage Loans to Total Loans

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Percent of consumer Home Equity Loans to Total Loans

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Percent of Consumer Installment Loans to Total Loans

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Percent of Consumer Real Estate Construction to Total Loans

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Percent of Consumer Real Estate Home Equity Lines of Credit to Total Loans

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Percent of Loans and Leases Receivable, Consumer Other to Total Loans

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Percent of Loans and Leases Receivable, Consumer Real Estate to Total Loans

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Percent Of One To Four Family Residential Mortgage Loans To Total Loans

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Percent Of Other Consumer Loans To Total Loans

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Percent Of Total Loans

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Percent Of Unearned Discounts To Total Loans

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Unearned discounts

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Reflects the gross carrying amount of unpaid loans issued to individuals to build, improve or remodel a residential home. Such loans are usually secured by the property; and after the construction period, the borrower generally will obtain long-term financing to replace and satisfy the construction loan.

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Gross amount under revolving lines of credit outstanding extended to a homeowner and collateralized by the equity in the home. Such lines of credit are generally subordinated to the homeowner's mortgage loan or loans. Loan proceeds are generally unrestricted as to use by the borrower.

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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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The total value of other non major installment loans (gross) made by financial institutions to consumers, the proceeds of which are used by individuals (borrowers) for purchases such as household goods, vacations, and other consumer items. Such loans should be repaid in periodic payments over a predetermined time period, are generally secured by the item purchased and may be either direct to the borrower (direct paper) or to the dealer (indirect paper or retail sales contract).

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

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The total gross amount of money lent to individual customers including construction financing, residential mortgage loans, and 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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The gross amount of other loans and leases not otherwise specified in the taxonomy.

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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 gross carrying amount of unpaid loans issued to businesses to provide financing on existing land or a building, which, pursuant to terms of the underlying debt instrument, are secured at a minimum but possibly exclusively by that real property. Mortgages represent permanent financing, and are issued to replace previously existing mortgages or pay off acquisition, development and construction loans, or to provide cash to the borrower.

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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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