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Securities (Tables) | 12 Months Ended
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Dec. 31, 2012
Securities [Abstract] |
Amortized costs, gross unrealized gains, gross unrealized losses and fair values for securities available for sale by major security type | The amortized cost and fair value of securities available for sale, with gross unrealized gains and losses, follows:
|  | December 31, 2012 |
Available for sale: |  | Amortized Cost |  |  | Gross Unrealized Gains |  |  | Gross Unrealized Losses |  |  | Fair Value |
U.S. Treasury |  | $ | 2,005 |  |  | $ | 68 |  |  | $ | --- |  |  | $ | 2,073 |
U.S. Government agencies and corporations |  |  | 128,805 |  |  |  | 1,381 |  |  |  | 622 |  |  |  | 129,564 |
States and political subdivisions |  |  | 35,029 |  |  |  | 1,753 |  |  |  | 3 |  |  |  | 36,779 |
Mortgage-backed securities |  |  | 4,202 |  |  |  | 367 |  |  |  | --- |  |  |  | 4,569 |
Corporate debt securities |  |  | 14,207 |  |  |  | 368 |  |  |  | --- |  |  |  | 14,575 |
Federal Home Loan Bank stock – restricted |  |  | 1,597 |  |  |  | --- |  |  |  | --- |  |  |  | 1,597 |
Federal Reserve Bank stock – restricted |  |  | 92 |  |  |  | --- |  |  |  | --- |  |  |  | 92 |
Other securities |  |  | 2,419 |  |  |  | 9 |  |  |  | 173 |  |  |  | 2,255 |
Total securities available for sale |  | $ | 188,356 |  |  | $ | 3,946 |  |  | $ | 798 |  |  | $ | 191,504 |
|  | December 31, 2011 |
Available for sale: |  | Amortized Cost |  |  | Gross Unrealized Gains |  |  | Gross Unrealized Losses |  |  | Fair Value |
U.S. Treasury |  | $ | 2,010 |  |  | $ | 140 |  |  | $ | --- |  |  | $ | 2,150 |
U.S. Government agencies and corporations |  |  | 94,716 |  |  |  | 1,307 |  |  |  | 20 |  |  |  | 96,003 |
States and political subdivisions |  |  | 47,118 |  |  |  | 2,034 |  |  |  | 30 |  |  |  | 49,122 |
Mortgage-backed securities |  |  | 7,156 |  |  |  | 569 |  |  |  | --- |  |  |  | 7,725 |
Corporate debt securities |  |  | 15,852 |  |  |  | 322 |  |  |  | 97 |  |  |  | 16,077 |
Federal Home Loan Bank stock – restricted |  |  | 1,574 |  |  |  | --- |  |  |  | --- |  |  |  | 1,574 |
Federal Reserve Bank stock – restricted |  |  | 92 |  |  |  | --- |  |  |  | --- |  |  |  | 92 |
Other securities |  |  | 2,330 |  |  |  | 7 |  |  |  | 162 |  |  |  | 2,175 |
Total securities available for sale |  | $ | 170,848 |  |  | $ | 4,379 |  |  | $ | 309 |  |  | $ | 174,918 |
Amortized cost and fair value of single maturity securities available for sale by contractual maturity | The amortized cost and fair value of single maturity securities available for sale at December 31, 2012, by contractual maturity, are shown below. Expected maturities may differ from contractual maturities because borrowers may have the right to call or prepay obligations with or without call or prepayment penalties. Mortgage-backed securities included in these totals are categorized by final maturity at December 31, 2012.
|  | December 31, 2012 |
|  | Amortized Cost |  |  | Fair Value |
Due in one year or less |  | $ | 16,688 |  |  | $ | 16,893 |
Due after one year through five years |  |  | 12,096 |  |  |  | 12,549 |
Due after five years through ten years |  |  | 11,987 |  |  |  | 12,875 |
Due after ten years |  |  | 144,165 |  |  |  | 145,931 |
No maturity |  |  | 3,420 |  |  |  | 3,256 |
|  | $ | 188,356 |  |  | $ | 191,504 |
Amortized costs, gross unrealized gains, gross unrealized losses and fair values for securities held to maturity by major security type | The amortized cost and fair value of securities held to maturity, with gross unrealized gains and losses, follows:
|  | December 31, 2012 |
Held to maturity: |  | Amortized Cost |  |  | Gross Unrealized Gains |  |  | Gross Unrealized Losses |  |  | Fair Value |
U.S. Government agencies and corporations |  | $ | 7,988 |  |  | $ | 563 |  |  | $ | --- |  |  | $ | 8,551 |
States and political subdivisions |  |  | 151,209 |  |  |  | 9,880 |  |  |  | 216 |  |  |  | 160,873 |
Mortgage-backed securities |  |  | 691 |  |  |  | 73 |  |  |  | --- |  |  |  | 764 |
Corporate debt securities |  |  | 651 |  |  |  | 7 |  |  |  | --- |  |  |  | 658 |
Total securities held to maturity |  | $ | 160,539 |  |  | $ | 10,523 |  |  | $ | 216 |  |  | $ | 170,846 |
|  | December 31, 2011 |
Held to maturity: |  | Amortized Cost |  |  | Gross Unrealized Gains |  |  | Gross Unrealized Losses |  |  | Fair Value |
U.S. Government agencies and corporations |  | $ | 22,057 |  |  | $ | 562 |  |  | $ | --- |  |  | $ | 22,619 |
States and political subdivisions |  |  | 119,381 |  |  |  | 6,775 |  |  |  | 15 |  |  |  | 126,141 |
Mortgage-backed securities |  |  | 902 |  |  |  | 94 |  |  |  | --- |  |  |  | 996 |
Corporate debt securities |  |  | 1,655 |  |  |  | 18 |  |  |  | --- |  |  |  | 1,673 |
Total securities held to maturity |  | $ | 143,995 |  |  | $ | 7,449 |  |  | $ | 15 |  |  | $ | 151,429 |
Amortized cost and fair value of single maturity securities held to maturity by contractual maturity | The amortized cost and fair value of single maturity securities held to maturity at December 31, 2012, by contractual maturity, are shown below. Expected maturities may differ from contractual maturities because borrowers may have the right to call or prepay obligations with or without call or prepayment penalties. Mortgage-backed securities included in these totals are categorized by final maturity at December 31, 2012.
|  | December 31, 2012 |
|  | Amortized Cost |  |  | Fair Value |
Due in one year or less |  | $ | 3,907 |  |  | $ | 3,958 |
Due after one year through five years |  |  | 8,537 |  |  |  | 8,814 |
Due after five years through ten years |  |  | 13,745 |  |  |  | 15,050 |
Due after ten years |  |  | 134,350 |  |  |  | 143,024 |
|  | $ | 160,539 |  |  | $ | 170,846 |
Temporarily impaired securities with gross unrealized losses and fair value | Information pertaining to securities with gross unrealized losses at December 31, 2012 and 2011 aggregated by investment category and length of time that individual securities have been in a continuous loss position, follows:
| December 31, 2012 |
| Less Than 12 Months |  | 12 Months or More |
| Fair Value |  |  | Unrealized Loss |  | Fair Value |  |  | Unrealized Loss |
U. S. Government agencies and corporations |  | $ | 44,351 |  |  | $ | 622 |  |  | $ | --- |  |  | $ | --- |
State and political subdivisions |  |  | 9,358 |  |  |  | 216 |  |  |  | 482 |  |  |  | 3 |
Other |  |  | --- |  |  |  | --- |  |  |  | 133 |  |  |  | 172 |
Total temporarily impaired securities |  | $ | 53,709 |  |  | $ | 838 |  |  | $ | 615 |  |  | $ | 176 |
| December 31, 2011 |
| Less Than 12 Months |  | 12 Months or More |
| Fair Value |  |  | Unrealized Loss |  | Fair Value |  |  | Unrealized Loss |
U. S. Government agencies and corporations |  | $ | 6,230 |  |  | $ | 20 |  |  | $ | --- |  |  | $ | --- |
State and political subdivisions |  |  | 3,527 |  |  |  | 19 |  |  |  | 981 |  |  |  | 26 |
Corporate debt securities |  |  | 4,916 |  |  |  | 97 |  |  |  | --- |  |  |  | --- |
Other |  |  | --- |  |  |  | --- |  |  |  | 142 |  |  |  | 162 |
Total temporarily impaired securities |  | $ | 14,673 |  |  | $ | 136 |  |  | $ | 1,123 |  |  | $ | 188 |

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