LOANS, Troubled Debt Restructuring (TDR) (Details) $ in Thousands	3 Months Ended
Mar. 31, 2018 USD ($) Loan	Mar. 31, 2017 USD ($) Loan	Dec. 31, 2017 USD ($) Loan
Financing Receivable, Modifications [Line Items]
TDRs, number \| Loan	211		226
TDRs, amount	$ 5,566		$ 6,135
Loans modified in TDR during the year, number \| Loan	7	21
Loans modified in TDR during the year, amount	$ 136	$ 721
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	67		72
TDRs, amount	$ 2,522		$ 2,728
Accruing [Member]
Financing Receivable, Modifications [Line Items]
TDRs, number \| Loan	144		154
TDRs, amount	$ 3,044		$ 3,407
Commercial Portfolio Segment [Member] \| Minimum [Member]
Financing Receivable, Modifications [Line Items]
Threshold balance of loans individually evaluated for impairment	$ 500
Commercial Portfolio Segment [Member] \| Business Lending [Member]
Financing Receivable, Modifications [Line Items]
TDRs, number \| Loan	11		15
TDRs, amount	$ 592		$ 719
Loans modified in TDR during the year, number \| Loan	1	0
Loans modified in TDR during the year, amount	$ 93	$ 0
Commercial Portfolio Segment [Member] \| Business Lending [Member] \| Nonaccrual [Member]
Financing Receivable, Modifications [Line Items]
TDRs, number \| Loan	8		8
TDRs, amount	$ 312		$ 218
Commercial Portfolio Segment [Member] \| Business Lending [Member] \| Accruing [Member]
Financing Receivable, Modifications [Line Items]
TDRs, number \| Loan	3		7
TDRs, amount	$ 280		$ 501
Residential Portfolio Segment [Member] \| Consumer Mortgage [Member]
Financing Receivable, Modifications [Line Items]
TDRs, number \| Loan	91		95
TDRs, amount	$ 3,627		$ 4,015
Loans modified in TDR during the year, number \| Loan	0	7
Loans modified in TDR during the year, amount	$ 0	$ 502
Residential Portfolio Segment [Member] \| Consumer Mortgage [Member] \| Nonaccrual [Member]
Financing Receivable, Modifications [Line Items]
TDRs, number \| Loan	48		51
TDRs, amount	$ 1,976		$ 2,265
Residential Portfolio Segment [Member] \| Consumer Mortgage [Member] \| Accruing [Member]
Financing Receivable, Modifications [Line Items]
TDRs, number \| Loan	43		44
TDRs, amount	$ 1,651		$ 1,750
Consumer Portfolio Segment [Member] \| Consumer Indirect [Member]
Financing Receivable, Modifications [Line Items]
TDRs, number \| Loan	68		71
TDRs, amount	$ 847		$ 883
Loans modified in TDR during the year, number \| Loan	4	8
Loans modified in TDR during the year, amount	$ 41	$ 106
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	68		71
TDRs, amount	$ 847		$ 883
Consumer Portfolio Segment [Member] \| Consumer Direct [Member]
Financing Receivable, Modifications [Line Items]
TDRs, number \| Loan	23		25
TDRs, amount	$ 65		$ 69
Loans modified in TDR during the year, number \| Loan	2	4
Loans modified in TDR during the year, amount	$ 2	$ 15
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	23		25
TDRs, amount	$ 65		$ 69
Consumer Portfolio Segment [Member] \| Home Equity [Member]
Financing Receivable, Modifications [Line Items]
TDRs, number \| Loan	18		20
TDRs, amount	$ 435		$ 449
Loans modified in TDR during the year, number \| Loan	0	2
Loans modified in TDR during the year, amount	$ 0	$ 98
Consumer Portfolio Segment [Member] \| Home Equity [Member] \| Nonaccrual [Member]
Financing Receivable, Modifications [Line Items]
TDRs, number \| Loan	11		13
TDRs, amount	$ 234		$ 245
Consumer Portfolio Segment [Member] \| Home Equity [Member] \| Accruing [Member]
Financing Receivable, Modifications [Line Items]
TDRs, number \| Loan	7		7
TDRs, amount	$ 201		$ 204

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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.

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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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