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Commitments and Off-Balance Sheet Risk (Tables) | 3 Months Ended
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Mar. 31, 2013
Commitments and Off-Balance Sheet Risk [Abstract] |
Summary of the contractual amounts of financial instruments with off-balance sheet risk |
|  | March 31, 2013 |  |  | December 31, 2012 |
Commercial unused lines of credit |  | $ | 230,160,000 |  |  | $ | 222,237,000 |
Unused lines of credit secured by 1 – 4 family residential properties |  |  | 23,892,000 |  |  |  | 24,250,000 |
Credit card unused lines of credit |  |  | 8,431,000 |  |  |  | 8,512,000 |
Other consumer unused lines of credit |  |  | 3,752,000 |  |  |  | 4,613,000 |
Commitments to extend credit |  |  | 94,000,000 |  |  |  | 64,565,000 |
Standby letters of credit |  |  | 10,340,000 |  |  |  | 10,591,000 |
|  | $ | 370,575,000 |  |  | $ | 334,768,000 |

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