Summary of Significant Accounting Policies (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Cash and Cash Equivalents [Abstract]
Cash on deposit with Federal Reserve Bank	$ 392,413	$ 622,152
Compensating balances with Federal Reserve Bank	1,412	1,057
Loans and Leases Receivable Disclosure [Abstract]
Mortgage loans held for sale	40,861	66,442
Impairment losses	616	70	0
Write-downs of OREO	3,512	6,724	7,464
Federal Home Loan Bank Stock and Federal Reserve Bank Stock [Abstract]
Federal Reserve Bank stock	13,357	13,357
Federal Home Loan Bank stock	7,003	6,687
Advertising expense	3,532	3,555	3,048
Share-based Compensation [Abstract]
Stock compensation expense	2,936	2,485	1,906
Tax benefits from stock-based compensation	$ 1,122	$ 950	$ 728

Federal Reserve Bank, Unrestricted Cash Held, Carrying Value

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Amount charged to advertising expense for the period, which are expenses incurred with the objective of increasing revenue for a specified brand, product or product line.

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Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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The amount of a specific compensating balance arrangement that is maintained under an agreement for a bank loan or future credit availability.

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The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

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Federal Home Loan Bank (FHLB) stock represents an equity interest in a FHLB. It does not have a readily determinable fair value because its ownership is restricted and it lacks a market (liquidity).

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Federal Reserve Bank stock represents an equity interest in the Federal Reserve Bank. It does not have a readily determinable fair value because its ownership is restricted and it lacks a market (liquidity).

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The aggregate amount of write-downs for impairments recognized during the period for long-lived assets held for abandonment, exchange or sale.

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The charge against earnings in the period to reduce the carrying amount of real property to fair value.

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Amount of mortgage loans held for sale. Excludes loans and leases covered under loss sharing agreements and loans classified as debt securities.

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