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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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