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FAIR VALUE (Details) - USD ($) | 3 Months Ended | 12 Months Ended |
--- | --- | --- | ---
Mar. 31, 2019 | Mar. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2018
Financial Assets: |  |  |  |
Estimated Fair Value | $ 266,721,000 |  |  | $ 242,258,000
Equity investments | 2,032,000 |  |  | 1,909,000
Impaired Loans, Fair Value Disclosure [Abstract] |  |  |  |
Level 2 to level 1 transfer amount | 0 | $ 0 |  |
Total Gains (Losses) | (1,093,000) | (709,000) |  |
Recurring |  |  |  |
Financial Assets: |  |  |  |
Obligations of U.S. Government and U.S. Government sponsored enterprises | 5,488,000 |  |  | 5,472,000
Mortgage-backed securities, residential | 203,938,000 |  |  | 183,192,000
Obligations of states and political subdivisions | 48,332,000 |  |  | 44,152,000
Corporate bonds and notes | 249,000 |  |  | 247,000
SBA loan pools | 8,714,000 |  |  | 9,195,000
Estimated Fair Value | 266,721,000 |  |  | 242,258,000
Equity investments | 1,198,000 |  |  | 1,075,000
Derivative assets | 4,091,000 |  |  | 3,142,000
Financial Liabilities: |  |  |  |
Derivative liabilities | 4,321,000 |  |  | 3,282,000
Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |  |  |
Financial Assets: |  |  |  |
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
Estimated Fair Value | 0 |  |  | 0
Equity investments | 1,198,000 |  |  | 1,075,000
Derivative assets | 0 |  |  | 0
Financial Liabilities: |  |  |  |
Derivative liabilities | 0 |  |  | 0
Recurring | Significant Other Observable Inputs (Level 2) |  |  |  |
Financial Assets: |  |  |  |
Obligations of U.S. Government and U.S. Government sponsored enterprises | 5,488,000 |  |  | 5,472,000
Mortgage-backed securities, residential | 203,938,000 |  |  | 183,192,000
Obligations of states and political subdivisions | 48,332,000 |  |  | 44,152,000
Corporate bonds and notes | 249,000 |  |  | 247,000
SBA loan pools | 8,714,000 |  |  | 9,195,000
Estimated Fair Value | 266,721,000 |  |  | 242,258,000
Equity investments | 0 |  |  | 0
Derivative assets | 4,091,000 |  |  | 3,142,000
Financial Liabilities: |  |  |  |
Derivative liabilities | 4,091,000 |  |  | 3,142,000
Recurring | Significant Unobservable Inputs (Level 3) |  |  |  |
Financial Assets: |  |  |  |
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
Estimated Fair Value | 0 |  |  | 0
Equity investments | 0 |  |  | 0
Derivative assets | 0 |  |  | 0
Financial Liabilities: |  |  |  |
Derivative liabilities | 230,000 |  |  | 140,000
Impaired Loans: | Non-recurring |  |  |  |
Impaired Loans, Fair Value Disclosure [Abstract] |  |  |  |
Total impaired loans | 2,913,000 |  |  | 1,456,000
Total Gains (Losses) | (1,785,000) |  | $ 240,000 |
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 | 2,913,000 |  |  | 1,456,000
Other real estate owned: | Non-recurring |  |  |  |
Impaired Loans, Fair Value Disclosure [Abstract] |  |  |  |
Total other real estate owned, net | 144,000 |  |  | 574,000
Total Gains (Losses) | 0 |  | (14,000) |
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 | 144,000 |  |  | 574,000
Commercial mortgages, other | Other real estate owned: | Non-recurring |  |  |  |
Impaired Loans, Fair Value Disclosure [Abstract] |  |  |  |
Total other real estate owned, net | 62,000 |  |  | 213,000
Total Gains (Losses) | 0 |  | 0 |
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 | 62,000 |  |  | 213,000
Home equity lines and loans | Other real estate owned: | Non-recurring |  |  |  |
Impaired Loans, Fair Value Disclosure [Abstract] |  |  |  |
Total other real estate owned, net |  |  |  | 157,000
Total Gains (Losses) |  |  | (14,000) |
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] |  |  |  |
Total other real estate owned, net |  |  |  | 0
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
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 |  |  |  | 157,000
Commercial mortgages |  |  |  |
Impaired Loans, Fair Value Disclosure [Abstract] |  |  |  |
Total Gains (Losses) | (1,289,000) | (125,000) |  |
Commercial mortgages | Commercial mortgages | Impaired Loans: | Non-recurring |  |  |  |
Impaired Loans, Fair Value Disclosure [Abstract] |  |  |  |
Total impaired loans | 2,913,000 |  |  | 1,456,000
Total Gains (Losses) | (1,785,000) |  | 240,000 |
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 | 2,913,000 |  |  | 1,456,000
Residential mortgages |  |  |  |
Impaired Loans, Fair Value Disclosure [Abstract] |  |  |  |
Total Gains (Losses) | 9,000 | (180,000) |  |
Residential mortgages | Other real estate owned: | Non-recurring |  |  |  |
Impaired Loans, Fair Value Disclosure [Abstract] |  |  |  |
Total other real estate owned, net | 27,000 |  |  | 204,000
Total Gains (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 | 27,000 |  |  | $ 204,000
Consumer Loans |  |  |  |
Impaired Loans, Fair Value Disclosure [Abstract] |  |  |  |
Total Gains (Losses) | 229,000 | $ (367,000) |  |
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 | 55,000 |  |  |
Total Gains (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 | $ 55,000 |  |  |

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