Fair Value of Financial Instruments, Part 3 (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2014	Dec. 31, 2013	Mar. 31, 2013	Dec. 31, 2012
Financial assets [Abstract]
Cash and cash equivalents	$ 733,130	$ 583,044	$ 444,774	$ 544,016
Securities available for sale	741,292	863,754
Held to maturity securities	86,669	90,305
Net loans	2,921,344	2,910,940
Accrued interest receivable	10,843	11,198
Financial liabilities [Abstract]
Demand deposits	327,779	318,456
Interest bearing deposits	3,659,508	3,609,592
Short-term borrowings	195,411	204,162
Accrued interest payable	471	468
Level 1 [Member]
Financial assets [Abstract]
Cash and cash equivalents	733,130	583,044
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	327,779	318,456
Interest bearing deposits	2,513,327	2,477,567
Short-term borrowings	0	0
Accrued interest payable	99	101
Level 2 [Member]
Financial assets [Abstract]
Cash and cash equivalents	0	0
Securities available for sale	741,282	863,744
Held to maturity securities	86,669	90,305
Net loans	0	0
Accrued interest receivable	2,953	3,452
Financial liabilities [Abstract]
Demand deposits	0	0
Interest bearing deposits	1,146,181	1,132,025
Short-term borrowings	195,411	204,162
Accrued interest payable	372	367
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	2,921,344	2,910,940
Accrued interest receivable	7,890	7,746
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	733,130	583,044
Securities available for sale	741,292	863,754
Held to maturity securities	82,136	86,215
Federal Reserve Bank and Federal Home Loan Bank stock	10,500	10,500
Net loans	2,893,967	2,861,095
Accrued interest receivable	10,843	11,198
Financial liabilities [Abstract]
Demand deposits	327,779	318,456
Interest bearing deposits	3,659,439	3,608,615
Short-term borrowings	195,411	204,162
Accrued interest payable	$ 471	$ 468

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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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