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Fair Value Measurements (Details) (USD $) In Thousands, unless otherwise specified | 9 Months Ended |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
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Sep. 30, 2012 | Sep. 30, 2012 Impaired Loans Gross [Member] | Sep. 30, 2012 Impairment allocation [Member] | Sep. 30, 2012 Impaired Loans Net [Member] | Sep. 30, 2012 Other Real Estate Owned Fair Value Disclosure [Member] | Sep. 30, 2012 Recurring [Member] | Dec. 31, 2011 Recurring [Member] | Sep. 30, 2012 Recurring [Member] Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Dec. 31, 2011 Recurring [Member] Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Sep. 30, 2012 Recurring [Member] Significant Other Observable Inputs (Level 2) [Member] | Dec. 31, 2011 Recurring [Member] Significant Other Observable Inputs (Level 2) [Member] | Sep. 30, 2012 Recurring [Member] Significant Unobservable Inputs (Level 3) [Member] | Dec. 31, 2011 Recurring [Member] Significant Unobservable Inputs (Level 3) [Member] | Sep. 30, 2012 Nonrecurring [Member] | Dec. 31, 2011 Nonrecurring [Member] | Sep. 30, 2012 Nonrecurring [Member] Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Dec. 31, 2011 Nonrecurring [Member] Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Sep. 30, 2012 Nonrecurring [Member] Significant Other Observable Inputs (Level 2) [Member] | Dec. 31, 2011 Nonrecurring [Member] Significant Other Observable Inputs (Level 2) [Member] | Sep. 30, 2012 Nonrecurring [Member] Significant Unobservable Inputs (Level 3) [Member] | Dec. 31, 2011 Nonrecurring [Member] Significant Unobservable Inputs (Level 3) [Member]
Financial assets and liabilities measured at fair value on a recurring basis [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
U.S. Treasury |  |  |  |  |  |  |  |  | $ 2,092 | $ 2,150 | $ 0 | $ 0 | $ 2,092 | $ 2,150 | $ 0 | $ 0 |  |  |  |  |  |  |  |
U.S. Government agencies and corporations |  |  |  |  |  |  |  |  | 127,619 | 96,003 | 0 | 0 | 127,619 | 96,003 | 0 | 0 |  |  |  |  |  |  |  |
State and political subdivisions |  |  |  |  |  |  |  |  | 40,256 | 49,122 | 0 | 0 | 40,256 | 49,122 | 0 | 0 |  |  |  |  |  |  |  |
Mortgage-backed Securities |  |  |  |  |  |  |  |  | 5,297 | 7,725 | 0 | 0 | 5,297 | 7,725 | 0 | 0 |  |  |  |  |  |  |  |
Corporate debt securities |  |  |  |  |  |  |  |  | 18,688 | 16,077 | 0 | 0 | 18,688 | 16,077 | 0 | 0 |  |  |  |  |  |  |  |
Other securities |  |  |  |  |  |  |  |  | 2,439 | 2,175 | 0 | 0 | 2,439 | 2,175 | 0 | 0 |  |  |  |  |  |  |  |
Total Securities Available for Sale |  |  |  |  |  |  |  |  | 196,391 | 173,252 | 0 | 0 | 196,391 | 173,252 | 0 | 0 |  |  |  |  |  |  |  |
Period of appraisal of real estate property | 12 months |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Impaired loans and OREO measured at fair value on nonrecurring basis [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Impaired loans net of valuation allowance |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 575 | 5,968 | 0 | 0 | 0 | 0 | 575 | 5,968
Other real estate owned net of valuation allowance |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1,894 | 1,489 | 0 | 0 | 0 | 0 | 1,894 | 1,489
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Carrying Value, beginning of period |  | 7,091 |  | (1,123) |  | 5,968 |  | 1,489 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Additions |  | 1,846 |  | (272) |  | 1,574 |  | 1,608 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Deletions due to Foreclosure |  | (2,222) |  | 449 |  | (1,773) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Sale of Property |  |  |  |  |  |  |  | (1,144) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Change in Balance/ Valuation Allowance |  | (555) | [1] | 163 | [1] | (392) | [1] | (59) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Impaired Loans Removed from Level 3 |  | (5,258) | [2] | 456 | [2] | (4,802) | [2] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Carrying Value, end of period |  | $ 902 |  | $ (327) |  | $ 575 |  | $ 1,894 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
[1] | The reported amounts represent changes in the balance due to principal payments by borrowers.
[2] | The reported amount represents loans that were valued using Level 3 inputs as of December 31, 2011 that no longer have impairment allocations based on Level 3 valuation, or for which Level 3 impairment allocations were reduced due to a updated valuation analysis.

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- Definition Amount of increase (decrease) of assets measured at fair value on a recurring basis using unobservable inputs (level 3). Such increase (decrease) may be may due to principal payments by borrowers, reductions in impairment measurements as a result of current valuation procedures or increases to valuation allowance. + References No definition available. + Details
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- Definition Additions that have taken place during the period in relation to assets measured at fair value and categorized within Level 3 of the fair value hierarchy. + References No definition available. + Details
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- Definition 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 fair value of impaired loans net of valuation allowance. + References No definition available. + Details
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- Definition 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 fair value of other real estate owned by bank. + References No definition available. + Details
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- Definition 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 debt issued by US states and political subdivisions. + References No definition available. + Details
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- Definition 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 US government agency issued debt securities. + References No definition available. + Details
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- Definition 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 US government issued debt securities. + References No definition available. + Details
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- Definition 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. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -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. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 + Details
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- Definition Sales that have taken place during the period in relation to assets measured at fair value and categorized within Level 3 of the fair value hierarchy. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=7578670&loc=d3e19207-110258 + Details
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- Definition Transfers out of assets measured at fair value and categorized within Level 3 of the fair value hierarchy that have taken place during the period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(3) -URI http://asc.fasb.org/extlink&oid=7578670&loc=d3e19207-110258 + Details
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- Definition This element represents an asset measured at fair value using significant unobservable inputs (Level 3) which is required for reconciliation purposes of beginning and ending balances. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=7578670&loc=d3e19207-110258 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 157 -Paragraph 32 -Subparagraph c -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. + Details
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- Definition 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 securitized, pay-through debt securities collateralized by real estate mortgage loans (mortgages) as of the balance sheet date which have been categorized as available-for-sale. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -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. Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Mortgage-Backed Securities -URI http://asc.fasb.org/extlink&oid=6517959 + Details
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