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FAIR VALUES - Quantitative Information (Details) - Significant Unobservable Inputs (Level 3) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2017 | Dec. 31, 2016
Recurring | Derivative liabilities |  |
Fair Value Inputs, Liabilities, Quantitative Information [Line Items] |  |
Liabilities, fair value, recurring | $ 75 | $ 68
Recurring | Corporate bonds and notes |  |
Fair Value Inputs, Liabilities, Quantitative Information [Line Items] |  |
Assets, fair value, recurring |  | 250
Non-recurring | Impaired Loans |  |
Fair Value Inputs, Liabilities, Quantitative Information [Line Items] |  |
Assets, fair value, nonrecurring | 507 | 2,850
Non-recurring | OREO |  |
Fair Value Inputs, Liabilities, Quantitative Information [Line Items] |  |
Assets, fair value, nonrecurring | $ 1,940 | $ 344
Minimum | Recurring | Derivative liabilities |  |
Fair Value Inputs, Liabilities, Quantitative Information [Line Items] |  |
Discount rate | 5.67% | 4.92%
Minimum | Recurring | Corporate bonds and notes |  |
Fair Value Inputs, Liabilities, Quantitative Information [Line Items] |  |
Discount rate |  | 1.73%
Maximum | Recurring | Derivative liabilities |  |
Fair Value Inputs, Liabilities, Quantitative Information [Line Items] |  |
Discount rate | 5.67% | 4.92%
Maximum | Recurring | Corporate bonds and notes |  |
Fair Value Inputs, Liabilities, Quantitative Information [Line Items] |  |
Discount rate |  | 1.73%
Weighted Average | Recurring | Derivative liabilities |  |
Fair Value Inputs, Liabilities, Quantitative Information [Line Items] |  |
Discount rate | 5.67% | 4.92%
Weighted Average | Recurring | Corporate bonds and notes |  |
Fair Value Inputs, Liabilities, Quantitative Information [Line Items] |  |
Discount rate |  | 1.73%
Residential Mortgage | Minimum | Non-recurring | OREO |  |
Fair Value Inputs, Liabilities, Quantitative Information [Line Items] |  |
Fair value inputs, discount to appraised value | 20.80% | 17.28%
Residential Mortgage | Maximum | Non-recurring | OREO |  |
Fair Value Inputs, Liabilities, Quantitative Information [Line Items] |  |
Fair value inputs, discount to appraised value | 48.17% | 27.97%
Residential Mortgage | Weighted Average | Non-recurring | OREO |  |
Fair Value Inputs, Liabilities, Quantitative Information [Line Items] |  |
Fair value inputs, discount to appraised value | 30.50% | 20.77%
Sales Comparison | Non-recurring | OREO |  |
Fair Value Inputs, Liabilities, Quantitative Information [Line Items] |  |
Assets, fair value, nonrecurring | $ 382 | $ 344
Sales Comparison | Commercial and Industrial | Non-recurring | Impaired Loans |  |
Fair Value Inputs, Liabilities, Quantitative Information [Line Items] |  |
Assets, fair value, nonrecurring | 96 |
Sales Comparison | Commercial and Industrial | Non-recurring | OREO |  |
Fair Value Inputs, Liabilities, Quantitative Information [Line Items] |  |
Assets, fair value, nonrecurring | $ 1,483 |
Sales Comparison | Commercial and Industrial | Minimum | Non-recurring | Impaired Loans |  |
Fair Value Inputs, Liabilities, Quantitative Information [Line Items] |  |
Fair value inputs, discount to appraised value | 0.00% |
Sales Comparison | Commercial and Industrial | Minimum | Non-recurring | OREO |  |
Fair Value Inputs, Liabilities, Quantitative Information [Line Items] |  |
Fair value inputs, discount to appraised value | 10.00% |
Sales Comparison | Commercial and Industrial | Maximum | Non-recurring | Impaired Loans |  |
Fair Value Inputs, Liabilities, Quantitative Information [Line Items] |  |
Fair value inputs, discount to appraised value | 36.07% |
Sales Comparison | Commercial and Industrial | Maximum | Non-recurring | OREO |  |
Fair Value Inputs, Liabilities, Quantitative Information [Line Items] |  |
Fair value inputs, discount to appraised value | 22.95% |
Sales Comparison | Commercial and Industrial | Weighted Average | Non-recurring | Impaired Loans |  |
Fair Value Inputs, Liabilities, Quantitative Information [Line Items] |  |
Fair value inputs, discount to appraised value | 33.02% |
Sales Comparison | Commercial and Industrial | Weighted Average | Non-recurring | OREO |  |
Fair Value Inputs, Liabilities, Quantitative Information [Line Items] |  |
Fair value inputs, discount to appraised value | 19.75% |
Sales Comparison | Commercial mortgages | Non-recurring | Impaired Loans |  |
Fair Value Inputs, Liabilities, Quantitative Information [Line Items] |  |
Assets, fair value, nonrecurring | $ 411 |
Sales Comparison | Commercial mortgages | Minimum | Non-recurring | Impaired Loans |  |
Fair Value Inputs, Liabilities, Quantitative Information [Line Items] |  |
Fair value inputs, discount to appraised value | 10.00% | 9.00%
Sales Comparison | Commercial mortgages | Maximum | Non-recurring | Impaired Loans |  |
Fair Value Inputs, Liabilities, Quantitative Information [Line Items] |  |
Fair value inputs, discount to appraised value | 89.98% | 10.00%
Sales Comparison | Commercial mortgages | Weighted Average | Non-recurring | Impaired Loans |  |
Fair Value Inputs, Liabilities, Quantitative Information [Line Items] |  |
Fair value inputs, discount to appraised value | 51.35% | 9.52%
Sales Comparison | Home equity lines and loans | Non-recurring | Impaired Loans |  |
Fair Value Inputs, Liabilities, Quantitative Information [Line Items] |  |
Assets, fair value, nonrecurring |  | $ 219
Sales Comparison | Home equity lines and loans | Non-recurring | OREO |  |
Fair Value Inputs, Liabilities, Quantitative Information [Line Items] |  |
Assets, fair value, nonrecurring | $ 75 |
Sales Comparison | Home equity lines and loans | Minimum | Non-recurring | Impaired Loans |  |
Fair Value Inputs, Liabilities, Quantitative Information [Line Items] |  |
Fair value inputs, discount to appraised value |  | 22.98%
Sales Comparison | Home equity lines and loans | Minimum | Non-recurring | OREO |  |
Fair Value Inputs, Liabilities, Quantitative Information [Line Items] |  |
Fair value inputs, discount to appraised value | 20.80% |
Sales Comparison | Home equity lines and loans | Maximum | Non-recurring | Impaired Loans |  |
Fair Value Inputs, Liabilities, Quantitative Information [Line Items] |  |
Fair value inputs, discount to appraised value |  | 22.98%
Sales Comparison | Home equity lines and loans | Maximum | Non-recurring | OREO |  |
Fair Value Inputs, Liabilities, Quantitative Information [Line Items] |  |
Fair value inputs, discount to appraised value | 20.80% |
Sales Comparison | Home equity lines and loans | Weighted Average | Non-recurring | Impaired Loans |  |
Fair Value Inputs, Liabilities, Quantitative Information [Line Items] |  |
Fair value inputs, discount to appraised value |  | 22.98%
Sales Comparison | Home equity lines and loans | Weighted Average | Non-recurring | OREO |  |
Fair Value Inputs, Liabilities, Quantitative Information [Line Items] |  |
Fair value inputs, discount to appraised value | 20.80% |
Income Approach Valuation Technique | Commercial mortgages | Non-recurring | Impaired Loans |  |
Fair Value Inputs, Liabilities, Quantitative Information [Line Items] |  |
Assets, fair value, nonrecurring |  | $ 2,631

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