Fair Value Disclosures (Carrying Amounts And Estimated Fair Values) (Details) (USD $) In Thousands	Sep. 30, 2011	Dec. 31, 2010	Sep. 30, 2010
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and due from banks	$ 254,074	$ 200,646	$ 201,353
Loans and leases	9,511,709	9,441,363	9,505,685
Deposits	9,558,631	9,191,207	9,202,178
Short-term borrowings	551,245	770,623
Carrying Amount [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and due from banks	254,074	200,646
Short-term investments	104,208	93,947
Investment securities	2,699,764	2,417,611
Loans and leases	9,511,709	9,441,363
Derivatives	23,748	17,348
Deposits	9,558,631	9,191,207
Short-term borrowings	551,245	770,623
FHLB borrowings	1,115,026	1,101,620
Long-term debt	672,162	705,954
Derivatives	76,085	48,560
Fair Value [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and due from banks	254,074	200,646
Short-term investments	104,208	93,947
Investment securities	2,699,764	2,417,611
Loans and leases	9,617,224	9,492,108
Derivatives	23,748	17,348
Deposits	9,403,964	9,265,942
Short-term borrowings	551,245	770,623
FHLB borrowings	1,177,460	1,167,743
Long-term debt	643,231	683,628
Derivatives	$ 76,085	$ 48,560

The aggregate amount of all Federal Home Loan Bank Advances.

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For banks and other depository institutions: Includes cash on hand (currency and coin), cash items in process of collection, noninterest bearing deposits due from other financial institutions (including corporate credit unions), and noninterest bearing balances with the Federal Reserve Banks, Federal Home Loan Banks and central banks.

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The aggregate of all deposit liabilities held by the entity, including foreign and domestic, interest and noninterest bearing; may include demand deposits, saving deposits, Negotiable Order of Withdrawal (NOW) and time deposits among others.

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Fair values as of the balance sheet date of all assets resulting from contracts that meet the criteria of being accounted for as derivative instruments, net of the effects of master netting arrangements.

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Fair values as of the balance sheet date of all liabilities resulting from contracts that meet the criteria of being accounted for as derivative instruments, net of the effects of master netting arrangements.

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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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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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Including current and noncurrent portions, aggregate carrying amount of long-term borrowings as of the balance sheet date. May include notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, which had initial maturities beyond one year or beyond the normal operating cycle, if longer, and after deducting unamortized discount or premiums, if any.

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Total debt and equity financial instruments including: (1) securities held-to-maturity, (2) trading securities, and (3) securities available-for-sale.

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Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

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Investments which are intended to be sold in the short term (usually less than one year or the normal operating cycle, whichever is longer) including trading securities, available-for-sale securities, held-to-maturity securities, and other short-term investments not otherwise listed in the existing taxonomy.

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