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Fair Value Accounting (Details) - Fair Value, Measurements, Recurring [Member] - USD ($) $ in Thousands | Dec. 31, 2017 | Dec. 31, 2016
--- | --- | ---
Securities available for sale: |  |
US government agencies | $ 8,653 | $ 6,159
SBA securities | 4,063 | 1,437
State and political subdivisions | 11,396 | 20,474
Mortgage-backed securities | 43,491 | 36,410
Mortgage loans held for sale | 11,790 | 7,801
Mortgage loan interest rate lock commitments | 196 | 256
Total assets measured at fair value on a recurring basis | 79,589 | 72,537
Liabilities |  |
MBS forward sales commitments | 28 | 3
Total liabilities measured at fair value on a recurring basis | 28 | 3
Level 1 [Member] |  |
Securities available for sale: |  |
US government agencies |  |
SBA securities |  |
State and political subdivisions |  |
Mortgage-backed securities |  |
Mortgage loans held for sale |  |
Mortgage loan interest rate lock commitments |  |
Total assets measured at fair value on a recurring basis |  |
Liabilities |  |
MBS forward sales commitments |  |
Total liabilities measured at fair value on a recurring basis |  |
Level 2 [Member] |  |
Securities available for sale: |  |
US government agencies | 8,653 | 6,159
SBA securities | 4,063 | 1,437
State and political subdivisions | 11,396 | 20,474
Mortgage-backed securities | 43,491 | 36,410
Mortgage loans held for sale | 11,790 | 7,801
Mortgage loan interest rate lock commitments | 196 | 256
Total assets measured at fair value on a recurring basis | 79,589 | 72,537
Liabilities |  |
MBS forward sales commitments | 28 | 3
Total liabilities measured at fair value on a recurring basis | 28 | 3
Level 3 [Member] |  |
Securities available for sale: |  |
US government agencies |  |
SBA securities |  |
State and political subdivisions |  |
Mortgage-backed securities |  |
Mortgage loans held for sale |  |
Mortgage loan interest rate lock commitments |  |
Total assets measured at fair value on a recurring basis |  |
Liabilities |  |
MBS forward sales commitments |  |
Total liabilities measured at fair value on a recurring basis |  |

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- Definition Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258 + Details
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