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Securities (Details 1) (USD $) In Thousands, unless otherwise specified | Mar. 31, 2013 | Dec. 31, 2012
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Summary of investments in unrealized loss position that were temporarily impaired |  |
Less than 12 months - Fair Value | $ 32,471 | $ 23,899
12 months or more - Fair Value |  |
Total - Fair Value | 32,471 | 23,899
Summary of investments in unrealized loss position that were temporarily impaired, Unrealized (Loss) |  |
Less than 12 months - Unrealized (Loss) | (363) | (319)
12 months or more - Unrealized (Loss) |  |
Total Unrealized (Loss) | (363) | (319)
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 | 26,066 | 19,612
12 months or more - Fair Value |  |
Total - Fair Value | 26,066 | 19,612
Summary of investments in unrealized loss position that were temporarily impaired, Unrealized (Loss) |  |
Less than 12 months - Unrealized (Loss) | (255) | (236)
12 months or more - Unrealized (Loss) |  |
Total Unrealized (Loss) | (255) | (236)
Obligations of states and political subdivisions [Member] |  |
Summary of investments in unrealized loss position that were temporarily impaired |  |
Less than 12 months - Fair Value | 6,405 | 4,287
12 months or more - Fair Value |  |
Total - Fair Value | 6,405 | 4,287
Summary of investments in unrealized loss position that were temporarily impaired, Unrealized (Loss) |  |
Less than 12 months - Unrealized (Loss) | (108) | (83)
12 months or more - Unrealized (Loss) |  |
Total Unrealized (Loss) | $ (108) | $ (83)

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