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Commitments and Off-Balance Sheet Risk (Tables) | 9 Months Ended
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Sep. 30, 2012
Commitments and Off-Balance Sheet Risk [Abstract] |
Summary of the contractual amounts of financial instruments with off-balance sheet risk |
|  | September 30, 2012 |  |  | December 31, 2011 |
Commercial unused lines of credit |  | $ | 195,363,000 |  |  | $ | 171,683,000 |
Unused lines of credit secured by 1 – 4 family residential properties |  |  | 24,063,000 |  |  |  | 24,663,000 |
Credit card unused lines of credit |  |  | 8,149,000 |  |  |  | 7,565,000 |
Other consumer unused lines of credit |  |  | 4,489,000 |  |  |  | 3,367,000 |
Commitments to extend credit |  |  | 90,448,000 |  |  |  | 30,929,000 |
Standby letters of credit |  |  | 10,965,000 |  |  |  | 15,923,000 |
|  | $ | 333,477,000 |  |  | $ | 254,130,000 |

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