Fair Value of Financial Instruments, Part 3 (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Financial assets [Abstract]
Cash and cash equivalents	$ 583,044	$ 544,016	$ 532,943	$ 444,250
Securities available for sale	863,754	912,092
Held to maturity securities	90,305	151,126
Net loans	2,910,940	2,771,705
Accrued interest receivable	11,198	11,752
Financial liabilities [Abstract]
Demand deposits	318,456	300,544
Interest bearing deposits	3,609,592	3,505,833
Short-term borrowings	204,162	159,846
Accrued interest payable	468	449
Fair Value Measurements Using Level 1 [Member]
Financial assets [Abstract]
Cash and cash equivalents	583,044	544,016
Securities available for sale	10	10
Held to maturity securities	0	0
Net loans	0	0
Accrued interest receivable	0	0
Financial liabilities [Abstract]
Demand deposits	318,456	300,544
Interest bearing deposits	2,477,567	2,426,170
Short-term borrowings	0	0
Accrued interest payable	101	103
Fair Value Measurements Using Level 2 [Member]
Financial assets [Abstract]
Cash and cash equivalents	0	0
Securities available for sale	863,744	912,082
Held to maturity securities	90,305	151,126
Net loans	0	0
Accrued interest receivable	3,452	4,114
Financial liabilities [Abstract]
Demand deposits	0	0
Interest bearing deposits	1,132,025	1,079,663
Short-term borrowings	204,162	159,846
Accrued interest payable	367	346
Fair Value Measurements Using Level 3 [Member]
Financial assets [Abstract]
Cash and cash equivalents	0	0
Securities available for sale	0	0
Held to maturity securities	0	0
Net loans	2,910,940	2,771,705
Accrued interest receivable	7,746	7,638
Financial liabilities [Abstract]
Demand deposits	0	0
Interest bearing deposits	0	0
Short-term borrowings	0	0
Accrued interest payable	0	0
Carrying Value [Member]
Financial assets [Abstract]
Cash and cash equivalents	583,044	544,016
Securities available for sale	863,754	912,092
Held to maturity securities	86,215	143,426
Federal Reserve Bank and Federal Home Loan Bank stock	10,500	9,632
Net loans	2,878,540	2,636,806
Accrued interest receivable	11,198	11,752
Financial liabilities [Abstract]
Demand deposits	318,456	300,544
Interest bearing deposits	3,608,615	3,503,649
Short-term borrowings	204,162	159,846
Accrued interest payable	$ 468	$ 449

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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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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

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