Fair Value (Schedule of Carrying Amounts and Estimated Fair Values of Financial Instruments) (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014	Mar. 31, 2014
Carrying amounts and estimated fair values of financial instruments:
Securities available for sale	$ 178,190us-gaap_AvailableForSaleSecurities	$ 164,034us-gaap_AvailableForSaleSecurities	$ 180,190us-gaap_AvailableForSaleSecurities
Securities held to maturity	174,756	182,411	57,192
Total loans, net of allowance	2,359,403	2,355,548	2,399,150
Accrued interest receivable	8,744us-gaap_InterestReceivable	8,920us-gaap_InterestReceivable	8,990us-gaap_InterestReceivable
FDIC Indemnification Asset.	18,452us-gaap_FDICIndemnificationAsset	22,569us-gaap_FDICIndemnificationAsset	35,504us-gaap_FDICIndemnificationAsset
Bank-owned life insurance	55,793us-gaap_BankOwnedLifeInsurance	55,421us-gaap_BankOwnedLifeInsurance	44,367us-gaap_BankOwnedLifeInsurance
Accrued interest payable	619	686	758
Carrying Amount [Member]
Carrying amounts and estimated fair values of financial instruments:
Cash and due from banks, noninterest-bearing	84,208	81,068
Due from banks, interest-bearing	159,527	171,248
Federal funds sold	752	768
Securities available for sale	178,190	164,034
Securities held to maturity	170,804	178,687
Presold mortgages in process of settlement	8,273	6,019
Total loans, net of allowance	2,359,403	2,355,548
Accrued interest receivable	8,744	8,920
FDIC Indemnification Asset.	18,452	22,569
Bank-owned life insurance	55,793	55,421
Deposits	2,693,614	2,695,906
Borrowings	116,394	116,394
Accrued interest payable	619	686
Fair Value [Member]
Carrying amounts and estimated fair values of financial instruments:
Cash and due from banks, noninterest-bearing	84,208	81,068
Due from banks, interest-bearing	159,527	171,248
Federal funds sold	752	768
Securities available for sale	178,190	164,034
Securities held to maturity	174,756	182,411
Presold mortgages in process of settlement	8,273	6,019
Total loans, net of allowance	2,335,626	2,328,244
Accrued interest receivable	8,744	8,920
FDIC Indemnification Asset.	17,964	21,856
Bank-owned life insurance	55,793	55,421
Deposits	2,693,961	2,696,153
Borrowings	106,844	105,407
Accrued interest payable	619	686
Level in Fair Value Hierachy [Member]
Carrying amounts and estimated fair values of financial instruments:
Cash and due from banks, noninterest-bearing	1	1
Due from banks, interest-bearing	1	1
Federal funds sold	1	1
Securities available for sale	2	2
Securities held to maturity	2	2
Presold mortgages in process of settlement	1	1
Total loans, net of allowance	3	3
Accrued interest receivable	1	1
FDIC Indemnification Asset.	3	3
Bank-owned life insurance	1	1
Deposits	2	2
Borrowings	2	2
Accrued interest payable	$ 2	$ 2

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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.

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Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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The carrying amount of a life insurance policy on an officer, executive or employee for which the reporting entity (a bank) is entitled to proceeds from the policy upon death of the insured or surrender of the insurance policy.

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Fair value portion 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.

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Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

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Fair value portion of deposit liabilities held by the entity, including, but not limited to, foreign and domestic, interest and noninterest bearing, demand deposits, saving deposits, negotiable orders of withdrawal (NOW) and time deposits.

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A bank's noninterest bearing demand deposits in other banks (such as correspondents).

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Carrying amount of receivable assets originating from the indemnification agreement with the Federal Deposit Insurance Corporation (FDIC), in which the FDIC is to partially cover losses.

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Fair value of investments in debt securities classified as held-to-maturity.

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Amount of interest payable on debt, including, but not limited to, trade payables.

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Carrying amount as of the balance sheet date of interest earned but not received. Also called accrued interest or accrued interest receivable.

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

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