LOANS, Troubled Debt Restructuring (TDR) (Details)	12 Months Ended
Dec. 31, 2019 USD ($) Loan	Dec. 31, 2018 USD ($) Loan
Troubled Debt Restructurings (TDRs) [Abstract]
TDRs, number \| Loan	248	218
TDRs, amount	$ 6,982,000	$ 5,525,000
Loans modified in TDR during the year, number \| Loan	73	52
Loans modified in TDR during the year, amount	$ 2,798,000	$ 1,035,000
Maximum [Member]
Troubled Debt Restructurings (TDRs) [Abstract]
Threshold balance of TDR loans collectively included in general loan loss allocation and qualitative review	$ 500,000
Nonaccrual [Member]
Troubled Debt Restructurings (TDRs) [Abstract]
TDRs, number \| Loan	80	62
TDRs, amount	$ 3,609,000	$ 2,388,000
Accruing [Member]
Troubled Debt Restructurings (TDRs) [Abstract]
TDRs, number \| Loan	168	156
TDRs, amount	$ 3,373,000	$ 3,137,000
Residential Portfolio Segment [Member] \| Consumer Mortgage [Member]
Troubled Debt Restructurings (TDRs) [Abstract]
TDRs, number \| Loan	106	92
TDRs, amount	$ 4,530,000	$ 3,755,000
Loans modified in TDR during the year, number \| Loan	22	9
Loans modified in TDR during the year, amount	$ 1,519,000	$ 470,000
Residential Portfolio Segment [Member] \| Consumer Mortgage [Member] \| Nonaccrual [Member]
Troubled Debt Restructurings (TDRs) [Abstract]
TDRs, number \| Loan	59	46
TDRs, amount	$ 2,638,000	$ 1,986,000
Residential Portfolio Segment [Member] \| Consumer Mortgage [Member] \| Accruing [Member]
Troubled Debt Restructurings (TDRs) [Abstract]
TDRs, number \| Loan	47	46
TDRs, amount	$ 1,892,000	$ 1,769,000
Commercial Portfolio Segment [Member] \| Minimum [Member]
Troubled Debt Restructurings (TDRs) [Abstract]
Threshold balance of loan individually evaluated for impairment	$ 500,000
Commercial Portfolio Segment [Member] \| Business Lending [Member]
Troubled Debt Restructurings (TDRs) [Abstract]
TDRs, number \| Loan	11	6
TDRs, amount	$ 882,000	$ 327,000
Loans modified in TDR during the year, number \| Loan	6	2
Loans modified in TDR during the year, amount	$ 685,000	$ 103,000
Commercial Portfolio Segment [Member] \| Business Lending [Member] \| Nonaccrual [Member]
Troubled Debt Restructurings (TDRs) [Abstract]
TDRs, number \| Loan	8	4
TDRs, amount	$ 681,000	$ 162,000
Commercial Portfolio Segment [Member] \| Business Lending [Member] \| Accruing [Member]
Troubled Debt Restructurings (TDRs) [Abstract]
TDRs, number \| Loan	3	2
TDRs, amount	$ 201,000	$ 165,000
Consumer Portfolio Segment [Member] \| Consumer Indirect [Member]
Troubled Debt Restructurings (TDRs) [Abstract]
TDRs, number \| Loan	84	77
TDRs, amount	$ 941,000	$ 857,000
Loans modified in TDR during the year, number \| Loan	33	32
Loans modified in TDR during the year, amount	$ 364,000	$ 320,000
Consumer Portfolio Segment [Member] \| Consumer Indirect [Member] \| Nonaccrual [Member]
Troubled Debt Restructurings (TDRs) [Abstract]
TDRs, number \| Loan	0	0
TDRs, amount	$ 0	$ 0
Consumer Portfolio Segment [Member] \| Consumer Indirect [Member] \| Accruing [Member]
Troubled Debt Restructurings (TDRs) [Abstract]
TDRs, number \| Loan	84	77
TDRs, amount	$ 941,000	$ 857,000
Consumer Portfolio Segment [Member] \| Consumer Direct [Member]
Troubled Debt Restructurings (TDRs) [Abstract]
TDRs, number \| Loan	23	22
TDRs, amount	$ 101,000	$ 71,000
Loans modified in TDR during the year, number \| Loan	6	6
Loans modified in TDR during the year, amount	$ 49,000	$ 24,000
Consumer Portfolio Segment [Member] \| Consumer Direct [Member] \| Nonaccrual [Member]
Troubled Debt Restructurings (TDRs) [Abstract]
TDRs, number \| Loan	0	0
TDRs, amount	$ 0	$ 0
Consumer Portfolio Segment [Member] \| Consumer Direct [Member] \| Accruing [Member]
Troubled Debt Restructurings (TDRs) [Abstract]
TDRs, number \| Loan	23	22
TDRs, amount	$ 101,000	$ 71,000
Consumer Portfolio Segment [Member] \| Home Equity [Member]
Troubled Debt Restructurings (TDRs) [Abstract]
TDRs, number \| Loan	24	21
TDRs, amount	$ 528,000	$ 515,000
Loans modified in TDR during the year, number \| Loan	6	3
Loans modified in TDR during the year, amount	$ 181,000	$ 118,000
Consumer Portfolio Segment [Member] \| Home Equity [Member] \| Nonaccrual [Member]
Troubled Debt Restructurings (TDRs) [Abstract]
TDRs, number \| Loan	13	12
TDRs, amount	$ 290,000	$ 240,000
Consumer Portfolio Segment [Member] \| Home Equity [Member] \| Accruing [Member]
Troubled Debt Restructurings (TDRs) [Abstract]
TDRs, number \| Loan	11	9
TDRs, amount	$ 238,000	$ 275,000

The threshold balance of financing receivable that is individually evaluated for impairment.

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- Definition

Threshold balance of financing receivables classified as a troubled debt restructuring that are collectively evaluated for impairment.

+ References

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Number of financing receivables that have been modified by troubled debt restructurings.

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Number of financing receivables that have been modified by troubled debt restructurings.

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Amount, after troubled debt restructuring, of modified financing receivable.

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Amount of financing receivable modified as troubled debt restructuring.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953676-111524

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 40
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=118939409&loc=d3e18845-111554

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