Fair Value Measurements (Details 7) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Assets:
Cash and due from banks	$ 90,090	$ 83,232
Federal funds sold and interest bearing deposits with other banks	1,676	702
Investment securities, available-for-sale	834,348	880,764
Mortgages held for sale	7,157	10,879
Loans and leases, net of reserve for loan and lease losses	3,383,611	3,244,242
Liabilities:
Long-term debt and mandatorily redeemable securities	58,440	71,021
Subordinated notes	58,764	58,764
Carrying or Contract Value
Assets:
Cash and due from banks	90,090	83,232
Federal funds sold and interest bearing deposits with other banks	1,676	702
Investment securities, available-for-sale	834,348	880,764
Other investments and trading account securities	22,586	22,755
Mortgages held for sale	7,157	10,879
Loans and leases, net of reserve for loan and lease losses	3,383,611	3,244,242
Cash surrender value of life insurance policies	58,057	56,572
Mortgage servicing rights	4,878	4,645
Interest rate swaps	10,902	16,126
Liabilities:
Deposits	3,679,416	3,624,347
Short-term borrowings	221,442	169,188
Long-term debt and mandatorily redeemable securities	58,440	71,021
Subordinated notes	58,764	58,764
Interest rate swaps	11,110	16,444
Fair Value
Assets:
Cash and due from banks	90,090	83,232
Federal funds sold and interest bearing deposits with other banks	1,676	702
Investment securities, available-for-sale	834,348	880,764
Other investments and trading account securities	22,586	22,755
Mortgages held for sale	7,157	10,879
Loans and leases, net of reserve for loan and lease losses	3,408,703	3,287,976
Cash surrender value of life insurance policies	58,057	56,572
Mortgage servicing rights	7,656	5,760
Interest rate swaps	10,902	16,126
Liabilities:
Deposits	3,686,218	3,641,280
Short-term borrowings	221,442	169,188
Long-term debt and mandatorily redeemable securities	57,837	71,557
Subordinated notes	71,707	72,914
Interest rate swaps	11,110	16,444
Off-balance-sheet instruments	166	188
Level 1
Assets:
Cash and due from banks	90,090	83,232
Federal funds sold and interest bearing deposits with other banks	1,676	702
Investment securities, available-for-sale	26,878	25,756
Other investments and trading account securities	22,586	22,755
Cash surrender value of life insurance policies	58,057	56,572
Liabilities:
Deposits	2,636,029	2,556,122
Short-term borrowings	152,714	161,138
Level 2
Assets:
Investment securities, available-for-sale	800,953	847,307
Mortgages held for sale	7,157	10,879
Interest rate swaps	10,902	16,126
Liabilities:
Deposits	1,050,189	1,085,158
Short-term borrowings	68,728	8,050
Long-term debt and mandatorily redeemable securities	57,837	71,557
Subordinated notes	71,707	72,914
Interest rate swaps	11,110	16,444
Off-balance-sheet instruments	166	188
Level 3
Assets:
Investment securities, available-for-sale	6,517	7,701
Loans and leases, net of reserve for loan and lease losses	3,408,703	3,287,976
Mortgage servicing rights	$ 7,656	$ 5,760

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This element represents the amount outstanding of funds lent to other depository institutions, securities brokers, or securities dealers in the form of Federal Funds sold; for example, immediately available funds lent under agreements or contracts that mature in one business day or roll over under a continuing contract, regardless of the nature of the transaction or the collateral involved, excluding overnight lending for commercial and industrial purposes. Also include Federal Funds sold under agreements to resell on a gross basis, excluding (1) sales of term Federal Funds, (2) due bills representing purchases of securities or other assets by the reporting bank that have not yet been delivered and similar instruments, (3) resale agreements that mature in more than one business day involving assets other than securities, and (4) yield maintenance dollar repurchase agreements. Also includes Federal Home Loan Bank cash and interest-bearing deposits with Federal Reserve Banks. In addition, this element also includes interest-bearing deposits in other financial institutions for relatively short periods of time including, for example, certificates of deposits, which are presented separately from cash on the balance sheet.

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This element represents the aggregate carrying amount of long-term borrowings as of the balance sheet date including Federal Home Loan Bank borrowings, current portion of long term debt and promissory notes. Also includes the amount that is required to be paid, determined under the conditions specified in the contract, if as of the reporting date, the shares are mandatorily redeemable after one year from the reporting date or operating cycle, if longer.

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Total common and preferred stock, including the amount of Federal Home Loan Bank (FHLB) and Federal Reserve Bank stock, (which is not mandatorily redeemable, redeemable at the option of the holder, or in any other way classified as liability) equity securities that are bought and held principally for the purpose of selling them in the near term (thus held for only a short period of time) or for equity securities formerly categorized as available-for-sale or held-to-maturity which the entity held as of the date it opted to account for such securities at fair value.

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This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.

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The fair value of financial liabilities, which are not recognized in the financial statements (off-balance sheet) because they fail to meet some other criterion for recognition.

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Fair value as of the balance sheet date of all derivative assets not designated as hedging instruments.

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Fair value as of the balance sheet date of all derivative liabilities not designated as hedging instruments.

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Including the current and noncurrent portions, the carrying value of junior subordinated long-term debt owed to unconsolidated subsidiary trusts as of the balance sheet date. Such debt places a lender in a lien position behind debt having a higher priority of repayment in liquidation of the entity's assets and was initially scheduled to be repaid after one year or beyond the normal operating cycle if longer.

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Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements.

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