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Asset Purchase (Details Textual) (USD $) | 9 Months Ended | 12 Months Ended |
--- | --- | --- | ---
Sep. 30, 2012 | Dec. 31, 2011 | Dec. 31, 2007 | Jul. 09, 2010
Asset Purchase (Textual) [Abstract] |  |  |  |
Deposits of close included in purchase |  |  |  | $ 28,000,000
Loans included in purchase |  |  |  | 14,000,000
Number of years amortized on straight line basis |  |  | 7 years |
Recognition of core deposit intangible asset with Knisely purchase |  |  | 1,100,000 |
Recognition of core deposit intangible asset with Hicksville purchase | 1,090,000 |  |  |
Number of years amortized over an estimated remaining economic useful life of deposits | 7 years |  |  |
Amortization expense |  | 312,000 |  |
Amortization expensed to date this year | $ 234,000 |  |  |

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