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LOANS, Troubled Debt Restructurings (TDRs) (Details) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018 USD ($) Loan	Sep. 30, 2017 USD ($) Loan	Sep. 30, 2018 USD ($) Loan	Sep. 30, 2017 USD ($) Loan	Dec. 31, 2017 USD ($) Loan
Troubled Debt Restructurings (TDRs) [Abstract]
TDRs, number | Loan	217		217		226
TDRs, amount	$ 5,645		$ 5,645		$ 6,135
Loans modified in TDR during the year, number | Loan	21	19	39	48
Loans modified in TDR during the year, amount	$ 322	$ 781	$ 782	$ 1,890
Maximum [Member]
Troubled Debt Restructurings (TDRs) [Abstract]
Threshold balance of TDR loans collectively included in general loan loss allocation and qualitative review	$ 500		$ 500
Nonaccrual [Member]
Troubled Debt Restructurings (TDRs) [Abstract]
TDRs, number | Loan	62		62		72
TDRs, amount	$ 2,380		$ 2,380		$ 2,728
Accruing [Member]
Troubled Debt Restructurings (TDRs) [Abstract]
TDRs, number | Loan	155		155		154
TDRs, amount	$ 3,265		$ 3,265		$ 3,407
Commercial Portfolio Segment [Member] | Minimum [Member]
Troubled Debt Restructurings (TDRs) [Abstract]
Threshold balance of loans individually evaluated for impairment	$ 500		$ 500
Commercial Portfolio Segment [Member] | Business Lending [Member]
Troubled Debt Restructurings (TDRs) [Abstract]
TDRs, number | Loan	8		8		15
TDRs, amount	$ 484		$ 484		$ 719
Loans modified in TDR during the year, number | Loan	0	1	1	4
Loans modified in TDR during the year, amount	$ 0	$ 51	$ 93	$ 414
Commercial Portfolio Segment [Member] | Business Lending [Member] | Nonaccrual [Member]
Troubled Debt Restructurings (TDRs) [Abstract]
TDRs, number | Loan	5		5		8
TDRs, amount	$ 165		$ 165		$ 218
Commercial Portfolio Segment [Member] | Business Lending [Member] | Accruing [Member]
Troubled Debt Restructurings (TDRs) [Abstract]
TDRs, number | Loan	3		3		7
TDRs, amount	$ 319		$ 319		$ 501
Residential Portfolio Segment [Member] | Consumer Mortgage [Member]
Troubled Debt Restructurings (TDRs) [Abstract]
TDRs, number | Loan	91		91		95
TDRs, amount	$ 3,783		$ 3,783		$ 4,015
Loans modified in TDR during the year, number | Loan	4	8	7	15
Loans modified in TDR during the year, amount	$ 195	$ 540	$ 407	$ 1,040
Residential Portfolio Segment [Member] | Consumer Mortgage [Member] | Nonaccrual [Member]
Troubled Debt Restructurings (TDRs) [Abstract]
TDRs, number | Loan	45		45		51
TDRs, amount	$ 2,000		$ 2,000		$ 2,265
Residential Portfolio Segment [Member] | Consumer Mortgage [Member] | Accruing [Member]
Troubled Debt Restructurings (TDRs) [Abstract]
TDRs, number | Loan	46		46		44
TDRs, amount	$ 1,783		$ 1,783		$ 1,750
Consumer Portfolio Segment [Member] | Consumer Indirect [Member]
Troubled Debt Restructurings (TDRs) [Abstract]
TDRs, number | Loan	76		76		71
TDRs, amount	$ 814		$ 814		$ 883
Loans modified in TDR during the year, number | Loan	14	8	24	22
Loans modified in TDR during the year, amount	$ 117	$ 181	$ 176	$ 323
Consumer Portfolio Segment [Member] | Consumer Indirect [Member] | Nonaccrual [Member]
Troubled Debt Restructurings (TDRs) [Abstract]
TDRs, number | Loan	0		0		0
TDRs, amount	$ 0		$ 0		$ 0
Consumer Portfolio Segment [Member] | Consumer Indirect [Member] | Accruing [Member]
Troubled Debt Restructurings (TDRs) [Abstract]
TDRs, number | Loan	76		76		71
TDRs, amount	$ 814		$ 814		$ 883
Consumer Portfolio Segment [Member] | Consumer Direct [Member]
Troubled Debt Restructurings (TDRs) [Abstract]
TDRs, number | Loan	22		22		25
TDRs, amount	$ 70		$ 70		$ 69
Loans modified in TDR during the year, number | Loan	2	1	5	4
Loans modified in TDR during the year, amount	$ 10	$ 1	$ 21	$ 7
Consumer Portfolio Segment [Member] | Consumer Direct [Member] | Nonaccrual [Member]
Troubled Debt Restructurings (TDRs) [Abstract]
TDRs, number | Loan	0		0		0
TDRs, amount	$ 0		$ 0		$ 0
Consumer Portfolio Segment [Member] | Consumer Direct [Member] | Accruing [Member]
Troubled Debt Restructurings (TDRs) [Abstract]
TDRs, number | Loan	22		22		25
TDRs, amount	$ 70		$ 70		$ 69
Consumer Portfolio Segment [Member] | Home Equity [Member]
Troubled Debt Restructurings (TDRs) [Abstract]
TDRs, number | Loan	20		20		20
TDRs, amount	$ 494		$ 494		$ 449
Loans modified in TDR during the year, number | Loan	1	1	2	3
Loans modified in TDR during the year, amount	$ 0	$ 8	$ 85	$ 106
Consumer Portfolio Segment [Member] | Home Equity [Member] | Nonaccrual [Member]
Troubled Debt Restructurings (TDRs) [Abstract]
TDRs, number | Loan	12		12		13
TDRs, amount	$ 215		$ 215		$ 245
Consumer Portfolio Segment [Member] | Home Equity [Member] | Accruing [Member]
Troubled Debt Restructurings (TDRs) [Abstract]
TDRs, number | Loan	8		8		7
TDRs, amount	$ 279		$ 279		$ 204

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