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FAIR VALUE - Quantitative Information (Details) - Significant Unobservable Inputs (Level 3) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2017	Dec. 31, 2016
Corporate Bonds and Notes | Recurring | Discounted cash flow
Information related to Level 3 non-recurring fair value measurement [Abstract]
Assets, fair value disclosure	$ 252	$ 250
Corporate Bonds and Notes | Recurring | Discounted cash flow | Minimum
Information related to Level 3 non-recurring fair value measurement [Abstract]
Credit spread	1.73%	1.73%
Corporate Bonds and Notes | Recurring | Discounted cash flow | Maximum
Information related to Level 3 non-recurring fair value measurement [Abstract]
Credit spread	1.73%	1.73%
Corporate Bonds and Notes | Recurring | Discounted cash flow | Weighted Average
Information related to Level 3 non-recurring fair value measurement [Abstract]
Credit spread	1.73%	1.73%
Impaired Loans: | Non-recurring
Information related to Level 3 non-recurring fair value measurement [Abstract]
Fair value	$ 2,995	$ 2,850
Other real estate owned: | Non-recurring
Information related to Level 3 non-recurring fair value measurement [Abstract]
Fair value	138	344
Other real estate owned: | Non-recurring | Sales comparison
Information related to Level 3 non-recurring fair value measurement [Abstract]
Fair value	138	344
Derivative Liabilities | Recurring | Historical trend
Information related to Level 3 non-recurring fair value measurement [Abstract]
Liabilities, fair value disclosure	$ 71	$ 68
Derivative Liabilities | Recurring | Historical trend | Minimum
Information related to Level 3 non-recurring fair value measurement [Abstract]
Credit default rate	5.07%	4.92%
Derivative Liabilities | Recurring | Historical trend | Maximum
Information related to Level 3 non-recurring fair value measurement [Abstract]
Credit default rate	5.07%	4.92%
Derivative Liabilities | Recurring | Historical trend | Weighted Average
Information related to Level 3 non-recurring fair value measurement [Abstract]
Credit default rate	5.07%	4.92%
Commercial and Industrial | Impaired Loans: | Non-recurring
Information related to Level 3 non-recurring fair value measurement [Abstract]
Fair value	$ 84
Commercial and Industrial | Impaired Loans: | Non-recurring | Sales comparison | Minimum
Information related to Level 3 non-recurring fair value measurement [Abstract]
Capitalization Rate	36.07%
Commercial and Industrial | Impaired Loans: | Non-recurring | Sales comparison | Maximum
Information related to Level 3 non-recurring fair value measurement [Abstract]
Capitalization Rate	36.07%
Commercial and Industrial | Impaired Loans: | Non-recurring | Sales comparison | Weighted Average
Information related to Level 3 non-recurring fair value measurement [Abstract]
Capitalization Rate	36.07%
Commercial mortgages, other | Impaired Loans: | Non-recurring
Information related to Level 3 non-recurring fair value measurement [Abstract]
Fair value		$ 2,631
Commercial mortgages, other | Impaired Loans: | Non-recurring | Sales comparison
Information related to Level 3 non-recurring fair value measurement [Abstract]
Fair value	$ 316
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	13.58%
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	42.95%
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	24.90%
Commercial mortgages, other | Impaired Loans: | Non-recurring | Income approach
Information related to Level 3 non-recurring fair value measurement [Abstract]
Fair value	$ 2,595
Commercial mortgages, other | Impaired Loans: | Non-recurring | Income approach | Minimum
Information related to Level 3 non-recurring fair value measurement [Abstract]
Capitalization Rate	9.00%	9.00%
Commercial mortgages, other | Impaired Loans: | Non-recurring | Income approach | Maximum
Information related to Level 3 non-recurring fair value measurement [Abstract]
Capitalization Rate	10.00%	10.00%
Commercial mortgages, other | Impaired Loans: | Non-recurring | Income approach | Weighted Average
Information related to Level 3 non-recurring fair value measurement [Abstract]
Capitalization Rate	9.52%	9.52%
Home equity lines and loans | Impaired Loans: | Non-recurring
Information related to Level 3 non-recurring fair value measurement [Abstract]
Fair value		$ 219
Home equity lines and loans | Impaired Loans: | Non-recurring | Sales comparison | Minimum
Information related to Level 3 non-recurring fair value measurement [Abstract]
Discount to appraised value		22.98%
Home equity lines and loans | Impaired Loans: | Non-recurring | Sales comparison | Maximum
Information related to Level 3 non-recurring fair value measurement [Abstract]
Discount to appraised value		22.98%
Home equity lines and loans | Impaired Loans: | Non-recurring | Sales comparison | Weighted Average
Information related to Level 3 non-recurring fair value measurement [Abstract]
Discount to appraised value		22.98%
Residential mortgages | Other real estate owned: | Non-recurring | Sales comparison | Minimum
Information related to Level 3 non-recurring fair value measurement [Abstract]
Discount to appraised value	17.28%	20.80%
Residential mortgages | Other real estate owned: | Non-recurring | Sales comparison | Maximum
Information related to Level 3 non-recurring fair value measurement [Abstract]
Discount to appraised value	36.37%	48.17%
Residential mortgages | 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	23.12%	30.50%

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

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