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Securities (Details 1) (USD $) In Thousands, unless otherwise specified | Jun. 30, 2012 | Dec. 31, 2011
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Summary of investments in unrealized loss position that were temporarily impaired |  |
Less than 12 months - Fair Value | $ 8,994 |
12 months or more - Fair Value |  |
Total - Fair Value | 8,994 |
Summary of investments in unrealized loss position that were temporarily impaired, Unrealized (Loss) |  |
Less than 12 months - Unrealized (Loss) | (94) |
12 months or more - Unrealized (Loss) |  |
Total Unrealized (Loss) | (94) |
U.S. agency and mortgage-backed securities [Member] |  |
Summary of investments in unrealized loss position that were temporarily impaired |  |
Less than 12 months - Fair Value | 4,023 | 3,955
12 months or more - Fair Value |  |
Total - Fair Value | 4,023 | 3,955
Summary of investments in unrealized loss position that were temporarily impaired, Unrealized (Loss) |  |
Less than 12 months - Unrealized (Loss) | (10) | (16)
12 months or more - Unrealized (Loss) |  |
Total Unrealized (Loss) | (10) | (16)
Obligations of states and political subdivisions [Member] |  |
Summary of investments in unrealized loss position that were temporarily impaired |  |
Less than 12 months - Fair Value | 4,971 |
12 months or more - Fair Value |  |
Total - Fair Value | 4,971 |
Summary of investments in unrealized loss position that were temporarily impaired, Unrealized (Loss) |  |
Less than 12 months - Unrealized (Loss) | (84) |
12 months or more - Unrealized (Loss) |  |
Total Unrealized (Loss) | $ (84) |

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