Fair Value Measurements (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	12 Months Ended
Mar. 31, 2013	Dec. 31, 2012
Financial assets [Abstract]
Securities available-for-sale	321,645	329,456
Carrying Value [Member]
Financial assets [Abstract]
Cash and Cash Equivalents	44,955	42,317
Securities available-for-sale	321,645	329,456
Securities held-to-maturity	570	570
Restricted securities	2,378	2,562
Loans, net of allowances for loan losses	450,251	463,809
Bank owned life insurance	22,040	21,824
Accrued Interest Receivable	2,484	2,420
Financial liabilities [Abstract]
Deposits	747,240	753,816
Overnight repurchase agreements	26,339	35,946
Term repurchase agreements	1,281	1,280
Federal Home Loan Bank advances	25,000	25,000
Accrued interest payable	400	439
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Financial assets [Abstract]
Cash and Cash Equivalents	44,955	42,317
Securities available-for-sale	0	0
Securities held-to-maturity	0	0
Restricted securities	0	0
Loans, net of allowances for loan losses	0	0
Bank owned life insurance	0	0
Accrued Interest Receivable	0	0
Financial liabilities [Abstract]
Deposits	0	0
Overnight repurchase agreements	0	0
Term repurchase agreements	0	0
Federal Home Loan Bank advances	0	0
Accrued interest payable	0	0
Significant Other Observable Inputs (Level 2) [Member]
Financial assets [Abstract]
Cash and Cash Equivalents	0	0
Securities available-for-sale	321,645	329,456
Securities held-to-maturity	573	574
Restricted securities	2,378	2,562
Loans, net of allowances for loan losses	0	0
Bank owned life insurance	22,040	21,824
Accrued Interest Receivable	2,484	2,420
Financial liabilities [Abstract]
Deposits	751,902	757,923
Overnight repurchase agreements	26,339	35,946
Term repurchase agreements	1,282	1,282
Federal Home Loan Bank advances	28,417	28,681
Accrued interest payable	400	439
Significant Unobservable Inputs (Level 3) [Member]
Financial assets [Abstract]
Cash and Cash Equivalents	0	0
Securities available-for-sale	0	0
Securities held-to-maturity	0	0
Restricted securities	0	0
Loans, net of allowances for loan losses	457,364	466,492
Bank owned life insurance	0	0
Accrued Interest Receivable	0	0
Financial liabilities [Abstract]
Deposits	0	0
Overnight repurchase agreements	0	0
Term repurchase agreements	0	0
Federal Home Loan Bank advances	0	0
Accrued interest payable	0	0
Impaired Loans, Residential 1-4 Family Real Estate [Member] \| Market Comparables [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value	2,966	3,009
Impaired Loans, Residential 1-4 Family Real Estate [Member] \| Market Comparables [Member] \| Minimum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Selling costs (in hundredths)		4.75%
Difference in comparables (in hundredths)		0.00%
Impaired Loans, Residential 1-4 Family Real Estate [Member] \| Market Comparables [Member] \| Maximum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Selling costs (in hundredths)	6.00%	6.00%
Difference in comparables (in hundredths)		5.00%
Impaired Loans, Residential 1-4 Family Real Estate [Member] \| Market Comparables [Member] \| Average [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Selling costs (in hundredths)		6.00%
Difference in comparables (in hundredths)		5.00%
Impaired Loans, Commercial Real Estate [Member] \| Market Comparables [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value	2,876	2,271
Impaired Loans, Commercial Real Estate [Member] \| Market Comparables [Member] \| Minimum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Selling costs (in hundredths)	6.00%	0.00%
Impaired Loans, Commercial Real Estate [Member] \| Market Comparables [Member] \| Maximum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Selling costs (in hundredths)	20.00%	6.00%
Age of appraisal (in hundredths)	46.00%
Impaired Loans, Commercial Real Estate [Member] \| Market Comparables [Member] \| Average [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Selling costs (in hundredths)	10.00%	4.00%
Impaired Loans, Second Mortgages [Member] \| Market Comparables [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value	971	42
Impaired Loans, Second Mortgages [Member] \| Market Comparables [Member] \| Maximum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Selling costs (in hundredths)	6.00%	6.00%
Impaired Loans, Commercial Loans [Member] \| Market Comparables [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value		64
Impaired Loans, Commercial Loans [Member] \| Market Comparables [Member] \| Maximum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Difference in comparables (in hundredths)		25.00%
Foreclosed Assets, Residential 1-4 Family [Member] \| Market Comparables [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value	431	676
Foreclosed Assets, Residential 1-4 Family [Member] \| Market Comparables [Member] \| Minimum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Selling costs (in hundredths)	6.00%	6.00%
Foreclosed Assets, Residential 1-4 Family [Member] \| Market Comparables [Member] \| Maximum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Selling costs (in hundredths)	10.00%	10.00%
Foreclosed Assets, Residential 1-4 Family [Member] \| Market Comparables [Member] \| Average [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Selling costs (in hundredths)	6.00%	6.00%
Foreclosed Assets, Commercial [Member] \| Market Comparables [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value	1,825	2,094
Foreclosed Assets, Commercial [Member] \| Market Comparables [Member] \| Minimum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Selling costs (in hundredths)	6.00%	6.00%
Foreclosed Assets, Commercial [Member] \| Market Comparables [Member] \| Maximum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Selling costs (in hundredths)	10.00%	10.00%
Foreclosed Assets, Commercial [Member] \| Market Comparables [Member] \| Average [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Selling costs (in hundredths)	6.00%	6.00%
Foreclosed Assets, Construction [Member] \| Market Comparables [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value	3,765	3,804
Foreclosed Assets, Construction [Member] \| Market Comparables [Member] \| Minimum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Selling costs (in hundredths)	6.00%	6.00%
Foreclosed Assets, Construction [Member] \| Market Comparables [Member] \| Maximum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Selling costs (in hundredths)	10.00%	10.00%
Foreclosed Assets, Construction [Member] \| Market Comparables [Member] \| Average [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Selling costs (in hundredths)	6.00%	6.00%

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This element represents the aggregate of the assets reported on the balance sheet at period end measured at fair value by the entity. This element is intended to be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements.

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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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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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