Fair Value Measurement (Details) (USD $) In Thousands, unless otherwise specified	9 Months Ended
Sep. 30, 2012	Dec. 31, 2011
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Discount for selling costs (in hundredths)	10.00%
Available-for-sale Securities [Abstract]
Securities available-for-sale	$ 341,170	$ 367,241
Financial Assets [Abstract]
Securities available-for-sale	341,170	367,241
Securities held-to-maturity	121,969	101,131
Carrying Value [Member]
Available-for-sale Securities [Abstract]
Securities available-for-sale	341,170	367,241
Financial Assets [Abstract]
Cash and cash equivalents	59,655	83,303
Time deposits held in banks	709	710
Securities available-for-sale	341,170	367,241
Securities held-to-maturity	117,628	100,472
Other investments	5,820	5,637
Loans, net	801,459	739,029
Cash surrender value of life insurance policies	4,912	4,853
Financial liabilities [Abstract]
Non-interest-bearing deposits	306,463	254,755
Interest-bearing deposits	872,549	910,051
Securities sold under agreements to repurchase	55,233	46,078
Junior subordinated debentures	15,465	15,465
Level 1 [Member]
Available-for-sale Securities [Abstract]
Securities available-for-sale	0	0
Financial Assets [Abstract]
Cash and cash equivalents	59,655	83,303
Time deposits held in banks	0	0
Securities available-for-sale	0	0
Securities held-to-maturity	0	0
Other investments	5,820	5,637
Loans, net	0	0
Cash surrender value of life insurance policies	0	0
Financial liabilities [Abstract]
Non-interest-bearing deposits	0	0
Interest-bearing deposits	0	0
Securities sold under agreements to repurchase	55,233	46,078
Junior subordinated debentures	0	0
Level 2 [Member]
Available-for-sale Securities [Abstract]
Securities available-for-sale	341,170	367,241
Financial Assets [Abstract]
Cash and cash equivalents	0	0
Time deposits held in banks	0	0
Securities available-for-sale	341,170	367,241
Securities held-to-maturity	121,969	101,131
Other investments	0	0
Loans, net	0	0
Cash surrender value of life insurance policies	4,912	4,853
Financial liabilities [Abstract]
Non-interest-bearing deposits	306,463	254,755
Interest-bearing deposits	618,483	585,763
Securities sold under agreements to repurchase	0	0
Junior subordinated debentures	8,248	8,248
Level 3 [Member]
Available-for-sale Securities [Abstract]
Securities available-for-sale	0	0
Financial Assets [Abstract]
Cash and cash equivalents	0	0
Time deposits held in banks	712	716
Securities available-for-sale	0	0
Securities held-to-maturity	0	0
Other investments	0	0
Loans, net	803,723	747,156
Cash surrender value of life insurance policies	0	0
Financial liabilities [Abstract]
Non-interest-bearing deposits	0	0
Interest-bearing deposits	255,786	327,441
Securities sold under agreements to repurchase	0	0
Junior subordinated debentures	7,630	9,095
Fair Value, Measurements, Recurring [Member]
Available-for-sale Securities [Abstract]
U.S. Government sponsored enterprises	31,311	94,999
Obligations of state and political subdivisions	83,119	96,149
GSE mortgage-backed securities	145,511	109,487
Asset-backed securities	12,546
Collateralized mortgage obligations: residential	38,663	41,468
Collateralized mortgage obligations: commercial	30,020	25,138
Securities available-for-sale	341,170	367,241
Financial Assets [Abstract]
Securities available-for-sale	341,170	367,241
Fair Value, Measurements, Recurring [Member] \| Level 1 [Member]
Available-for-sale Securities [Abstract]
U.S. Government sponsored enterprises	0	0
Obligations of state and political subdivisions	0	0
GSE mortgage-backed securities	0	0
Asset-backed securities	0
Collateralized mortgage obligations: residential	0	0
Collateralized mortgage obligations: commercial	0	0
Securities available-for-sale	0	0
Financial Assets [Abstract]
Securities available-for-sale	0	0
Fair Value, Measurements, Recurring [Member] \| Level 2 [Member]
Available-for-sale Securities [Abstract]
U.S. Government sponsored enterprises	31,311	94,999
Obligations of state and political subdivisions	83,119	96,149
GSE mortgage-backed securities	145,511	109,487
Asset-backed securities	12,546
Collateralized mortgage obligations: residential	38,663	41,468
Collateralized mortgage obligations: commercial	30,020	25,138
Securities available-for-sale	341,170	367,241
Financial Assets [Abstract]
Securities available-for-sale	341,170	367,241
Fair Value, Measurements, Recurring [Member] \| Level 3 [Member]
Available-for-sale Securities [Abstract]
U.S. Government sponsored enterprises	0	0
Obligations of state and political subdivisions	0	0
GSE mortgage-backed securities	0	0
Asset-backed securities	0
Collateralized mortgage obligations: residential	0	0
Collateralized mortgage obligations: commercial	0	0
Securities available-for-sale	0	0
Financial Assets [Abstract]
Securities available-for-sale	0	0
Fair Value, Measurements, Nonrecurring [Member]
Assets and Liabilities Measured on Nonrecurring Basis
Impaired Loans	2,213	2,994
Other real estate	6,608	7,369
Fair Value, Measurements, Nonrecurring [Member] \| Level 1 [Member]
Assets and Liabilities Measured on Nonrecurring Basis
Impaired Loans	0	0
Other real estate	0	0
Fair Value, Measurements, Nonrecurring [Member] \| Level 2 [Member]
Assets and Liabilities Measured on Nonrecurring Basis
Impaired Loans	2,213	2,994
Other real estate	6,608	7,369
Fair Value, Measurements, Nonrecurring [Member] \| Level 3 [Member]
Assets and Liabilities Measured on Nonrecurring Basis
Impaired Loans	0	0
Other real estate	$ 0	$ 0

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Commission rate discount on sales with real estate agents.

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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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-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 25

-Paragraph 1

-Subparagraph (b)

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-Name Accounting Standards Codification

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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 includes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of accounts that have the general characteristics of demand deposits in that the Company may deposit additional funds at any time and also effectively may withdraw funds at any time without prior notice or penalty. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid investments that are both readily convertible to known amounts of cash, and so near their maturity that they present minimal risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months.

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

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-Paragraph 8

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-Name Accounting Standards Codification

-Glossary Cash

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-Name Accounting Standards Codification

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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 element represents the portion of a 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 the amount that could be realized under a life insurance contract or contracts owned by the Company as of the date of the statement of financial position. Such Company-owned life insurance policies are commonly known as corporate-owned life insurance (COLI) or bank-owned life insurance (BOLI).

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-Name Accounting Standards Codification

-Glossary Cash Surrender Value

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-Name Emerging Issues Task Force (EITF)

-Number 88-5

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-Name FASB Technical Bulletin (FTB)

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Amount of subordinated debt obligations (also known as subordinated loan, subordinated bond, subordinated debenture or junior debt) which has a priority ranking after other debts in a dissolution, measured at fair value.

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-Name Statement of Financial Accounting Standard (FAS)

-Number 157

-Paragraph 32

-Subparagraph a

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-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Glossary Loan

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-Publisher AICPA

-Name Audit and Accounting Guide (AAG)

-Number AAG-DEP

-Paragraph 15

-IssueDate 2006-05-01

-Chapter 7

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Name Accounting Standards Codification

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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. The amount of securities that an institution sells and agrees to repurchase (seller-borrower) at a specified date for a specified price, net of any reductions or offsets. Most repurchase agreements involve obligations of the federal government or its agencies, but other financial instruments, such as commercial paper, banker's acceptances, and negotiable certificates of deposit (CDs), are sometimes used in repurchase agreements. A repurchase agreement is similar to the seller-borrower's borrowing funds equal to the sales price of the related securities with the securities as collateral. Maturities of such agreements are flexible and generally vary from one day to 270 days.

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-Name Audit and Accounting Guide (AAG)

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