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FAIR VALUE - Quantitative Information (Details) - Significant Unobservable Inputs (Level 3) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2019 | Dec. 31, 2018
Impaired Loans: | Non-recurring |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Assets, fair value disclosure | $ 2,913 | $ 1,456
Other real estate owned: | Non-recurring |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Assets, fair value disclosure | 144 | 574
Derivative Liabilities | Recurring | Historical trend |  |
Information related to Level 3 non-recurring fair value measurement [Abstract] |  |
Liabilities, fair value disclosure | $ 230 | $ 140
Derivative Liabilities | Recurring | Historical trend | Minimum |  |
Information related to Level 3 non-recurring fair value measurement [Abstract] |  |
Credit default rate | 7.27% | 7.46%
Derivative Liabilities | Recurring | Historical trend | Maximum |  |
Information related to Level 3 non-recurring fair value measurement [Abstract] |  |
Credit default rate | 7.27% | 7.46%
Derivative Liabilities | Recurring | Historical trend | Weighted Average |  |
Information related to Level 3 non-recurring fair value measurement [Abstract] |  |
Credit default rate | 7.27% | 7.46%
Commercial and Industrial | Impaired Loans: | Non-recurring | Sales comparison |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Assets, fair value disclosure |  | $ 1,456
Commercial and Industrial | Impaired Loans: | Non-recurring | Sales comparison | Minimum |  |
Information related to Level 3 non-recurring fair value measurement [Abstract] |  |
Discount to appraised value |  | 11.76%
Commercial and Industrial | Impaired Loans: | Non-recurring | Sales comparison | Maximum |  |
Information related to Level 3 non-recurring fair value measurement [Abstract] |  |
Discount to appraised value |  | 11.76%
Commercial and Industrial | Impaired Loans: | Non-recurring | Sales comparison | Weighted Average |  |
Information related to Level 3 non-recurring fair value measurement [Abstract] |  |
Discount to appraised value |  | 11.76%
Commercial and Industrial | Other real estate owned: | Non-recurring | Sales comparison | Minimum |  |
Information related to Level 3 non-recurring fair value measurement [Abstract] |  |
Discount to appraised value | 22.00% | 10.00%
Commercial and Industrial | Other real estate owned: | Non-recurring | Sales comparison | Maximum |  |
Information related to Level 3 non-recurring fair value measurement [Abstract] |  |
Discount to appraised value | 22.00% | 24.80%
Commercial and Industrial | Other real estate owned: | Non-recurring | Sales comparison | Weighted Average |  |
Information related to Level 3 non-recurring fair value measurement [Abstract] |  |
Discount to appraised value | 22.00% | 17.72%
Commercial mortgages, other | Impaired Loans: | Non-recurring | Sales comparison |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Assets, fair value disclosure | $ 2,913 |
Commercial mortgages, other | Impaired Loans: | Non-recurring | Sales comparison | Minimum |  |
Information related to Level 3 non-recurring fair value measurement [Abstract] |  |
Discount to appraised value |  | 10.00%
Commercial mortgages, other | Impaired Loans: | Non-recurring | Sales comparison | Maximum |  |
Information related to Level 3 non-recurring fair value measurement [Abstract] |  |
Discount to appraised value |  | 11.76%
Commercial mortgages, other | Impaired Loans: | Non-recurring | Sales comparison | Weighted Average |  |
Information related to Level 3 non-recurring fair value measurement [Abstract] |  |
Discount to appraised value |  | 10.89%
Commercial mortgages, other | Other real estate owned: | Non-recurring | Sales comparison |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Assets, fair value disclosure | $ 62 | $ 213
Residential mortgages | Other real estate owned: | Non-recurring | Minimum |  |
Information related to Level 3 non-recurring fair value measurement [Abstract] |  |
Discount to appraised value | 13.14% | 20.80%
Residential mortgages | Other real estate owned: | Non-recurring | Maximum |  |
Information related to Level 3 non-recurring fair value measurement [Abstract] |  |
Discount to appraised value | 13.14% | 39.78%
Residential mortgages | Other real estate owned: | Non-recurring | Weighted Average |  |
Information related to Level 3 non-recurring fair value measurement [Abstract] |  |
Discount to appraised value | 13.14% | 22.94%
Residential mortgages | Other real estate owned: | Non-recurring | Sales comparison |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Assets, fair value disclosure | $ 27 | $ 204
Home equity lines and loans | Other real estate owned: | Non-recurring | Sales comparison |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Assets, fair value disclosure | $ 55 | $ 157
Home equity lines and loans | Other real estate owned: | Non-recurring | Sales comparison | Minimum |  |
Information related to Level 3 non-recurring fair value measurement [Abstract] |  |
Discount to appraised value | 20.80% | 20.80%
Home equity lines and loans | Other real estate owned: | Non-recurring | Sales comparison | Maximum |  |
Information related to Level 3 non-recurring fair value measurement [Abstract] |  |
Discount to appraised value | 20.80% | 20.80%
Home equity lines and loans | Other real estate owned: | Non-recurring | Sales comparison | Weighted Average |  |
Information related to Level 3 non-recurring fair value measurement [Abstract] |  |
Discount to appraised value | 20.80% | 20.80%

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