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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, 2020	Dec. 31, 2019
Impaired Loans: | Non-recurring
Information related to Level 3 non-recurring fair value measurement [Abstract]
Assets, fair value disclosure	$ 1,554	$ 1,554
Other real estate owned: | Non-recurring
Information related to Level 3 non-recurring fair value measurement [Abstract]
Assets, fair value disclosure	$ 380	$ 517
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	20.80%	20.80%
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	20.80%	20.80%
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	20.80%	20.80%
Commercial mortgages, other | Impaired Loans: | Non-recurring | Sales comparison
Information related to Level 3 non-recurring fair value measurement [Abstract]
Assets, fair value disclosure	$ 1,554	$ 1,554
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	10.31%	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	10.31%	10.00%
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	10.31%	10.00%
Commercial mortgages, other | Other real estate owned: | Non-recurring | Sales comparison
Information related to Level 3 non-recurring fair value measurement [Abstract]
Assets, fair value disclosure	$ 111	$ 111
Residential mortgages | Other real estate owned: | Non-recurring | Minimum
Information related to Level 3 non-recurring fair value measurement [Abstract]
Discount to appraised value	0.00%	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	0.00%	35.29%
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	0.00%	24.09%
Residential mortgages | Other real estate owned: | Non-recurring | Sales comparison
Information related to Level 3 non-recurring fair value measurement [Abstract]
Assets, fair value disclosure	$ 178	$ 284
Home equity lines and loans | Other real estate owned: | Non-recurring | Sales comparison
Information related to Level 3 non-recurring fair value measurement [Abstract]
Assets, fair value disclosure	$ 91	$ 122
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	27.49%	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	27.49%	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	27.49%	20.80%
Derivative Liabilities | Recurring | Historical trend
Information related to Level 3 non-recurring fair value measurement [Abstract]
Liabilities, fair value disclosure	$ 430	$ 365
Derivative Liabilities | Recurring | Historical trend | Minimum
Information related to Level 3 non-recurring fair value measurement [Abstract]
Credit default rate	12.86%	7.30%
Derivative Liabilities | Recurring | Historical trend | Maximum
Information related to Level 3 non-recurring fair value measurement [Abstract]
Credit default rate	20.75%	7.30%
Derivative Liabilities | Recurring | Historical trend | Weighted Average
Information related to Level 3 non-recurring fair value measurement [Abstract]
Credit default rate	13.82%	7.30%

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Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
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