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Summary of Significant Accounting Policies (Details) (USD $) In Thousands, except Share data, unless otherwise specified | 12 Months Ended
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Dec. 31, 2012 | Dec. 31, 2011 | Dec. 31, 2010
Loans [Abstract] |  |  |
Number of days of delinquent loans, interest accrual discontinued | 90 days |  |
Minimum number of days of discontinued loan payments for modified loan to be placed on nonaccrual | 90 days |  |
Number of days past due | 30 days |  |
Allowance for Loan Losses [Abstract] |  |  |
Threshold for designation to impaired status | $ 250,000 |  |
Minimum number of days consumer loans are past due for losses to be charged off | 120 days |  |
Maximum number of days consumer loans are past due for losses to be charged off | 180 days |  |
Number of days loans secured by residential or commercial real estate are past due for losses to be charged off | 180 days |  |
Rate Lock Commitments [Abstract] |  |  |
Period of time between issuance of loan commitment and closing and sale of loans, lower range | 30 days |  |
Period of time between issuance of loan commitments and closing and sale of loans, upper range | 60 days |  |
Earnings per common share [Abstract] |  |  |
Average number of common shares outstanding (in shares) | 6,942,411 | 6,936,869 | 6,933,474
Effect of dilutive options (in shares) | 17,456 | 13,994 | 16,462
Average number of common shares outstanding used to calculate diluted earnings per common share (in shares) | 6,959,867 | 6,950,863 | 6,949,936
Average number of shares not included in computation of diluted net income per common share (in shares) | 0 | 5,750 | 7,750
Advertising [Abstract] |  |  |
Advertising cost charged to expenses | $ 169 | $ 184 | $ 163
Minimum [Member] | Customer Deposit Intangibles [Member] |  |  |
Finite-Lived Intangible Assets [Line Items] |  |  |
Estimated useful life | 10 years |  |
Maximum [Member] | Customer Deposit Intangibles [Member] |  |  |
Finite-Lived Intangible Assets [Line Items] |  |  |
Estimated useful life | 12 years |  |
Premises [Member] |  |  |
Property, Plant and Equipment [Line Items] |  |  |
Estimated useful life | 40 years |  |
Furniture, Fixtures and Equipment [Member] | Minimum [Member] |  |  |
Property, Plant and Equipment [Line Items] |  |  |
Estimated useful life | 3 years |  |
Furniture, Fixtures and Equipment [Member] | Maximum [Member] |  |  |
Property, Plant and Equipment [Line Items] |  |  |
Estimated useful life | 10 years |  |
Computer Software [Member] |  |  |
Property, Plant and Equipment [Line Items] |  |  |
Estimated useful life | 3 years |  |

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- Definition The minimum number of days consumer loans are past due for losses on such loans to be written off. + References No definition available. + Details
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- Definition Minimum number of days of no loan payments due to loan modification for the loan to be placed on nonaccrual. + References No definition available. + Details
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- Definition Number of days loans secured by residential or commercial real estate are past due for losses to be written off. + References No definition available. + Details
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