LOANS, Troubled Debt Restructuring (TDR) (Details) $ in Thousands	12 Months Ended
Dec. 31, 2017 USD ($) Loan	Dec. 31, 2016 USD ($) Loan
Financing Receivable, Modifications [Line Items]
TDRs, number \| Loan	226	214
TDRs, amount	$ 6,135	$ 5,530
Loans modified in TDR during the year, number \| Loan	74	48
Loans modified in TDR during the year, amount	$ 2,268	$ 1,157
Maximum [Member]
Financing Receivable, Modifications [Line Items]
Threshold balance of TDR loans collectively included in general loan loss allocation and qualitative review	$ 500
Nonaccrual [Member]
Financing Receivable, Modifications [Line Items]
TDRs, number \| Loan	72	56
TDRs, amount	$ 2,728	$ 1,832
Accruing [Member]
Financing Receivable, Modifications [Line Items]
TDRs, number \| Loan	154	158
TDRs, amount	$ 3,407	$ 3,698
Residential Portfolio Segment [Member] \| Consumer Mortgage [Member]
Financing Receivable, Modifications [Line Items]
TDRs, number \| Loan	95	81
TDRs, amount	$ 4,015	$ 3,476
Loans modified in TDR during the year, number \| Loan	23	9
Loans modified in TDR during the year, amount	$ 1,254	$ 597
Residential Portfolio Segment [Member] \| Consumer Mortgage [Member] \| Nonaccrual [Member]
Financing Receivable, Modifications [Line Items]
TDRs, number \| Loan	51	36
TDRs, amount	$ 2,265	$ 1,520
Residential Portfolio Segment [Member] \| Consumer Mortgage [Member] \| Accruing [Member]
Financing Receivable, Modifications [Line Items]
TDRs, number \| Loan	44	45
TDRs, amount	$ 1,750	$ 1,956
Commercial Portfolio Segment [Member] \| Minimum [Member]
Financing Receivable, Modifications [Line Items]
Threshold balance of loan individually evaluated for impairment	$ 500
Commercial Portfolio Segment [Member] \| Business Lending [Member]
Financing Receivable, Modifications [Line Items]
TDRs, number \| Loan	15	11
TDRs, amount	$ 719	$ 781
Loans modified in TDR during the year, number \| Loan	8	0
Loans modified in TDR during the year, amount	$ 412	$ 0
Commercial Portfolio Segment [Member] \| Business Lending [Member] \| Nonaccrual [Member]
Financing Receivable, Modifications [Line Items]
TDRs, number \| Loan	8	6
TDRs, amount	$ 218	$ 91
Commercial Portfolio Segment [Member] \| Business Lending [Member] \| Accruing [Member]
Financing Receivable, Modifications [Line Items]
TDRs, number \| Loan	7	5
TDRs, amount	$ 501	$ 690
Consumer Portfolio Segment [Member] \| Consumer Indirect [Member]
Financing Receivable, Modifications [Line Items]
TDRs, number \| Loan	71	78
TDRs, amount	$ 883	$ 771
Loans modified in TDR during the year, number \| Loan	33	33
Loans modified in TDR during the year, amount	$ 490	$ 459
Consumer Portfolio Segment [Member] \| Consumer Indirect [Member] \| Nonaccrual [Member]
Financing Receivable, Modifications [Line Items]
TDRs, number \| Loan	0	0
TDRs, amount	$ 0	$ 0
Consumer Portfolio Segment [Member] \| Consumer Indirect [Member] \| Accruing [Member]
Financing Receivable, Modifications [Line Items]
TDRs, number \| Loan	71	78
TDRs, amount	$ 883	$ 771
Consumer Portfolio Segment [Member] \| Consumer Direct [Member]
Financing Receivable, Modifications [Line Items]
TDRs, number \| Loan	25	23
TDRs, amount	$ 69	$ 65
Loans modified in TDR during the year, number \| Loan	6	3
Loans modified in TDR during the year, amount	$ 17	$ 51
Consumer Portfolio Segment [Member] \| Consumer Direct [Member] \| Nonaccrual [Member]
Financing Receivable, Modifications [Line Items]
TDRs, number \| Loan	0	0
TDRs, amount	$ 0	$ 0
Consumer Portfolio Segment [Member] \| Consumer Direct [Member] \| Accruing [Member]
Financing Receivable, Modifications [Line Items]
TDRs, number \| Loan	25	23
TDRs, amount	$ 69	$ 65
Consumer Portfolio Segment [Member] \| Home Equity [Member]
Financing Receivable, Modifications [Line Items]
TDRs, number \| Loan	20	21
TDRs, amount	$ 449	$ 437
Loans modified in TDR during the year, number \| Loan	4	3
Loans modified in TDR during the year, amount	$ 95	$ 50
Consumer Portfolio Segment [Member] \| Home Equity [Member] \| Nonaccrual [Member]
Financing Receivable, Modifications [Line Items]
TDRs, number \| Loan	13	14
TDRs, amount	$ 245	$ 221
Consumer Portfolio Segment [Member] \| Home Equity [Member] \| Accruing [Member]
Financing Receivable, Modifications [Line Items]
TDRs, number \| Loan	7	7
TDRs, amount	$ 204	$ 216

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953676-111524

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- Definition

Post-modification amount of investment in financing receivables modified by troubled debt restructurings.

+ References

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- Definition

The amount of the outstanding recorded investment related to financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 40
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=82895541&loc=d3e18845-111554

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