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           Other Operating Income And Expense Included In Noninterest Income And Noninterest Expense (Detail) (USD $) 
        In Thousands, unless otherwise specified  | 
        12 Months Ended | ||
|---|---|---|---|
| 
           Dec. 31, 2012 
         | 
        
           Dec. 31, 2011 
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           Dec. 31, 2010 
         | 
      |
| Other Operating Income | |||
| (Loss) gain on sale of other real estate owned | $ (105) | $ 76 | $ (203) | 
| Credit card income | 1,064 | 481 | 30 | 
| Other income | 744 | 650 | 744 | 
| Other Operating Income | 1,703 | 1,207 | 571 | 
| Other Operating Expenses | |||
| Postage | 159 | 194 | 173 | 
| Telephone | 385 | 409 | 358 | 
| Data processing | 2,202 | 2,023 | 1,983 | 
| Other loan expenses | 2,836 | 2,406 | 1,027 | 
| Supplies | 320 | 356 | 263 | 
| Customer and public relations | 791 | 689 | 477 | 
| Marketing | 454 | 406 | 313 | 
| Sales and use tax | 198 | 208 | 141 | 
| Donations and contributions | 482 | 437 | 261 | 
| Directors fees | 286 | 235 | 216 | 
| Prepayment penalties FHLB advances | 0 | 738 | 0 | 
| Other | 2,609 | 2,313 | 2,071 | 
| Other Operating Expenses | $ 10,722 | $ 10,414 | $ 7,283 | 
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- Definition 
          it represent about Credit Card Income No definition available. 
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- Definition 
          it disclousure about Customer And Public Relations No definition available. 
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- Definition 
          The aggregate of other operating expenses. No definition available. 
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- Details 
          
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- Details 
          
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- Definition 
          The expenses incurred during the period for penalties. No definition available. 
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- Definition 
          The expenses incurred during the period for sales and use tax. No definition available. 
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- Definition 
          Amount of repayments and penalties incurred in the satisfaction or roll-over of Federal Home Loan Bank (FHLB) advance. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Definition 
          The net gain (loss) resulting from sales and other disposals of other real estate owned, increases (decreases) in the valuation allowance for foreclosed real estate, and write-downs of other real estate owned after acquisition or physical possession. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Definition 
          The amount of expenses incurred in the period for information technology and data processing products and services. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Definition 
          Expenses paid for obtaining loans which includes expenses such as application and origination fees. No definition available. 
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- Definition 
          Expenditures for planning and executing the conception, pricing, promotion, and distribution of ideas, goods, and services. Costs of public relations and corporate promotions are typically considered to be marketing costs. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Definition 
          Noninterest expense related to directors' fees which are fees paid by an Entity to its directors. Directors' fees may be paid in addition to salary and other benefits. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Definition 
          This element represents a sum total of expenses not separately reflected on the income statement for the period. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Definition 
          Reflects the sum of all other revenue and income recognized by the entity in the period not otherwise specified in the income statement. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Definition 
          The total amount of other operating income, the components of which are not separately disclosed on the income statement, from items that are associated with the entity's normal revenue producing operation. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Definition 
          Amount of expense associated with postage. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Definition 
          The aggregate amount of expenses directly related to the supplies and postage. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Definition 
          Utilities costs incurred during the reporting period for services, such as water, sewer, gas, electricity and telephone required to operate a building. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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