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FAIR VALUE (Details) - USD ($) | 3 Months Ended | 12 Months Ended |
--- | --- | --- | ---
Mar. 31, 2018 | Mar. 31, 2017 | Dec. 31, 2017 | Dec. 31, 2016
Impaired Loans, Fair Value Disclosure [Abstract] |  |  |  |
Provision for loan and lease losses | $ (709,000) | $ (1,040,000) |  |
Fair value, assets, level 2 to level 1 transfers, amount | 0 |  |  |
Recurring |  |  |  |
Financial Assets [Abstract] |  |  |  |
Obligations of U.S. Government and U.S. Government sponsored enterprises | 15,451,000 |  | $ 15,491,000 |
Mortgage-backed securities, residential | 207,819,000 |  | 219,909,000 |
Obligations of states and political subdivisions | 51,617,000 |  | 53,132,000 |
Corporate bonds and notes | 249,000 |  | 251,000 |
SBA loan pools | 3,848,000 |  | 4,308,000 |
Total available for sale securities | 278,984,000 |  | 293,091,000 |
Corporate stocks | 1,225,000 |  | 1,192,000 |
Derivative assets | 1,820,000 |  | 974,000 |
Derivative liabilities | 1,870,000 |  | 1,049,000 |
Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |  |  |
Financial Assets [Abstract] |  |  |  |
Obligations of U.S. Government and U.S. Government sponsored enterprises | 0 |  | 0 |
Mortgage-backed securities, residential | 0 |  | 0 |
Obligations of states and political subdivisions | 0 |  | 0 |
Corporate bonds and notes | 0 |  | 0 |
SBA loan pools | 0 |  | 0 |
Total available for sale securities | 0 |  | 0 |
Corporate stocks | 1,225,000 |  | 1,192,000 |
Derivative assets | 0 |  | 0 |
Derivative liabilities | 0 |  | 0 |
Recurring | Significant Other Observable Inputs (Level 2) |  |  |  |
Financial Assets [Abstract] |  |  |  |
Obligations of U.S. Government and U.S. Government sponsored enterprises | 15,451,000 |  | 15,491,000 |
Mortgage-backed securities, residential | 207,819,000 |  | 219,909,000 |
Obligations of states and political subdivisions | 51,617,000 |  | 53,132,000 |
Corporate bonds and notes | 249,000 |  | 251,000 |
SBA loan pools | 3,848,000 |  | 4,308,000 |
Total available for sale securities | 278,984,000 |  | 293,091,000 |
Corporate stocks | 0 |  | 0 |
Derivative assets | 1,820,000 |  | 974,000 |
Derivative liabilities | 1,820,000 |  | 974,000 |
Recurring | Significant Unobservable Inputs (Level 3) |  |  |  |
Financial Assets [Abstract] |  |  |  |
Obligations of U.S. Government and U.S. Government sponsored enterprises | 0 |  | 0 |
Mortgage-backed securities, residential | 0 |  | 0 |
Obligations of states and political subdivisions | 0 |  | 0 |
Corporate bonds and notes | 0 |  | 0 |
SBA loan pools | 0 |  | 0 |
Total available for sale securities | 0 |  | 0 |
Corporate stocks | 0 |  | 0 |
Derivative assets | 0 |  | 0 |
Derivative liabilities | 50,000 |  | 75,000 |
Impaired Loans: | Non-recurring |  |  |  |
Impaired Loans, Fair Value Disclosure [Abstract] |  |  |  |
Total impaired loans | 350,000 |  | 507,000 |
Provision for loan and lease losses | (59,000) |  | (175,000) |
Impaired Loans: | Non-recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |  |  |
Impaired Loans, Fair Value Disclosure [Abstract] |  |  |  |
Total impaired loans | 0 |  | 0 |
Impaired Loans: | Non-recurring | Significant Other Observable Inputs (Level 2) |  |  |  |
Impaired Loans, Fair Value Disclosure [Abstract] |  |  |  |
Total impaired loans | 0 |  | 0 |
Impaired Loans: | Non-recurring | Significant Unobservable Inputs (Level 3) |  |  |  |
Impaired Loans, Fair Value Disclosure [Abstract] |  |  |  |
Total impaired loans | 350,000 |  | 507,000 |
Other real estate owned: | Non-recurring |  |  |  |
Impaired Loans, Fair Value Disclosure [Abstract] |  |  |  |
Total other real estate owned, net | 1,832,000 |  | 1,940,000 |
Provision for loan and lease losses | 0 |  | (43,000) |
Other real estate owned: | Non-recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |  |  |
Impaired Loans, Fair Value Disclosure [Abstract] |  |  |  |
Total other real estate owned, net | 0 |  | 0 |
Other real estate owned: | Non-recurring | Significant Other Observable Inputs (Level 2) |  |  |  |
Impaired Loans, Fair Value Disclosure [Abstract] |  |  |  |
Total other real estate owned, net | 0 |  | 0 |
Other real estate owned: | Non-recurring | Significant Unobservable Inputs (Level 3) |  |  |  |
Impaired Loans, Fair Value Disclosure [Abstract] |  |  |  |
Total other real estate owned, net | 1,832,000 |  | 1,940,000 |
Commercial mortgages, other | Other real estate owned: | Non-recurring |  |  |  |
Impaired Loans, Fair Value Disclosure [Abstract] |  |  |  |
Total other real estate owned, net | 1,474,000 |  | 1,483,000 |
Provision for loan and lease losses | 0 |  | (43,000) |
Commercial mortgages, other | Other real estate owned: | Non-recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |  |  |
Impaired Loans, Fair Value Disclosure [Abstract] |  |  |  |
Total other real estate owned, net | 0 |  | 0 |
Commercial mortgages, other | Other real estate owned: | Non-recurring | Significant Other Observable Inputs (Level 2) |  |  |  |
Impaired Loans, Fair Value Disclosure [Abstract] |  |  |  |
Total other real estate owned, net | 0 |  | 0 |
Commercial mortgages, other | Other real estate owned: | Non-recurring | Significant Unobservable Inputs (Level 3) |  |  |  |
Impaired Loans, Fair Value Disclosure [Abstract] |  |  |  |
Total other real estate owned, net | 1,474,000 |  | 1,483,000 |
Home equity lines and loans | Other real estate owned: | Non-recurring |  |  |  |
Impaired Loans, Fair Value Disclosure [Abstract] |  |  |  |
Provision for loan and lease losses |  |  | 0 |
Home equity lines & loans |  |  |  | $ 75,000
Home equity lines and loans | Other real estate owned: | Non-recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |  |  |
Impaired Loans, Fair Value Disclosure [Abstract] |  |  |  |
Home equity lines & loans |  |  |  | 0
Home equity lines and loans | Other real estate owned: | Non-recurring | Significant Other Observable Inputs (Level 2) |  |  |  |
Impaired Loans, Fair Value Disclosure [Abstract] |  |  |  |
Home equity lines & loans |  |  |  | 0
Home equity lines and loans | Other real estate owned: | Non-recurring | Significant Unobservable Inputs (Level 3) |  |  |  |
Impaired Loans, Fair Value Disclosure [Abstract] |  |  |  |
Home equity lines & loans |  |  |  | $ 75,000
Commercial and agricultural: |  |  |  |
Impaired Loans, Fair Value Disclosure [Abstract] |  |  |  |
Provision for loan and lease losses | (37,000) | (42,000) |  |
Commercial and agricultural: | Commercial and industrial | Impaired Loans: | Non-recurring |  |  |  |
Impaired Loans, Fair Value Disclosure [Abstract] |  |  |  |
Total impaired loans | 12,000 |  | 96,000 |
Provision for loan and lease losses | 0 |  | (70,000) |
Commercial and agricultural: | Commercial and industrial | Impaired Loans: | Non-recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |  |  |
Impaired Loans, Fair Value Disclosure [Abstract] |  |  |  |
Total impaired loans | 0 |  | 0 |
Commercial and agricultural: | Commercial and industrial | Impaired Loans: | Non-recurring | Significant Other Observable Inputs (Level 2) |  |  |  |
Impaired Loans, Fair Value Disclosure [Abstract] |  |  |  |
Total impaired loans | 0 |  | 0 |
Commercial and agricultural: | Commercial and industrial | Impaired Loans: | Non-recurring | Significant Unobservable Inputs (Level 3) |  |  |  |
Impaired Loans, Fair Value Disclosure [Abstract] |  |  |  |
Total impaired loans | 12,000 |  | 96,000 |
Commercial mortgages: |  |  |  |
Impaired Loans, Fair Value Disclosure [Abstract] |  |  |  |
Provision for loan and lease losses | (125,000) | (478,000) |  |
Commercial mortgages: | Commercial mortgages | Impaired Loans: | Non-recurring |  |  |  |
Impaired Loans, Fair Value Disclosure [Abstract] |  |  |  |
Total impaired loans | 338,000 |  | 411,000 |
Provision for loan and lease losses | (59,000) |  | (105,000) |
Commercial mortgages: | Commercial mortgages | Impaired Loans: | Non-recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |  |  |
Impaired Loans, Fair Value Disclosure [Abstract] |  |  |  |
Total impaired loans | 0 |  | 0 |
Commercial mortgages: | Commercial mortgages | Impaired Loans: | Non-recurring | Significant Other Observable Inputs (Level 2) |  |  |  |
Impaired Loans, Fair Value Disclosure [Abstract] |  |  |  |
Total impaired loans | 0 |  | 0 |
Commercial mortgages: | Commercial mortgages | Impaired Loans: | Non-recurring | Significant Unobservable Inputs (Level 3) |  |  |  |
Impaired Loans, Fair Value Disclosure [Abstract] |  |  |  |
Total impaired loans | 338,000 |  | 411,000 |
Residential mortgages |  |  |  |
Impaired Loans, Fair Value Disclosure [Abstract] |  |  |  |
Provision for loan and lease losses | (180,000) | 16,000 |  |
Residential mortgages | Other real estate owned: | Non-recurring |  |  |  |
Impaired Loans, Fair Value Disclosure [Abstract] |  |  |  |
Total other real estate owned, net | 283,000 |  | 382,000 |
Provision for loan and lease losses | 0 |  | 0 |
Residential mortgages | Other real estate owned: | Non-recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |  |  |
Impaired Loans, Fair Value Disclosure [Abstract] |  |  |  |
Total other real estate owned, net | 0 |  | 0 |
Residential mortgages | Other real estate owned: | Non-recurring | Significant Other Observable Inputs (Level 2) |  |  |  |
Impaired Loans, Fair Value Disclosure [Abstract] |  |  |  |
Total other real estate owned, net | 0 |  | 0 |
Residential mortgages | Other real estate owned: | Non-recurring | Significant Unobservable Inputs (Level 3) |  |  |  |
Impaired Loans, Fair Value Disclosure [Abstract] |  |  |  |
Total other real estate owned, net | 283,000 |  | $ 382,000 |
Consumer loans: |  |  |  |
Impaired Loans, Fair Value Disclosure [Abstract] |  |  |  |
Provision for loan and lease losses | (367,000) | $ (536,000) |  |
Consumer loans: | Home equity lines and loans | Other real estate owned: | Non-recurring |  |  |  |
Impaired Loans, Fair Value Disclosure [Abstract] |  |  |  |
Total other real estate owned, net | 75,000 |  |  |
Provision for loan and lease losses | 0 |  |  |
Consumer loans: | Home equity lines and loans | Other real estate owned: | Non-recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |  |  |
Impaired Loans, Fair Value Disclosure [Abstract] |  |  |  |
Total other real estate owned, net | 0 |  |  |
Consumer loans: | Home equity lines and loans | Other real estate owned: | Non-recurring | Significant Other Observable Inputs (Level 2) |  |  |  |
Impaired Loans, Fair Value Disclosure [Abstract] |  |  |  |
Total other real estate owned, net | 0 |  |  |
Consumer loans: | Home equity lines and loans | Other real estate owned: | Non-recurring | Significant Unobservable Inputs (Level 3) |  |  |  |
Impaired Loans, Fair Value Disclosure [Abstract] |  |  |  |
Total other real estate owned, net | $ 75,000 |  |  |

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