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Asset Purchase (Details Textual) (USD $) | 3 Months Ended | 12 Months Ended |  |
--- | --- | --- | --- | ---
Mar. 31, 2013 | Dec. 31, 2012 | Dec. 31, 2007 | Dec. 31, 2007 Knisely [Member] | Jul. 09, 2010 Hicksville [Member]
Asset Purchase (Additional Textual) [Abstract] |  |  |  |  |
Recognition of core deposit intangible asset with acquired purchase |  |  |  | $ 1,100,000 | $ 1,090,000
Asset Purchase (Textual) [Abstract] |  |  |  |  |
Number of years amortized on straight line basis |  |  | 7 years |  |
Number of years amortized over an estimated remaining economic useful life of deposits | 7 years |  |  |  |
Amortization expense | 313,000 | 312,000 |  |  |
Amortization expensed to date this year | $ 78,000 |  |  |  |

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