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LOANS AND ALLOWANCE FOR LOAN LOSSES (Narrative) (Details) | 3 Months Ended | 9 Months Ended |  |  |  |
--- | --- | --- | --- | --- | --- | ---
Sep. 30, 2017 USD ($) loan | Sep. 30, 2016 USD ($) loan | Sep. 30, 2017 USD ($) loan | Sep. 30, 2016 USD ($) loan | Jun. 30, 2017 USD ($) | Dec. 31, 2016 USD ($) | Jun. 30, 2016 USD ($) | Dec. 31, 2015 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |  |  |
Non-Accrual Loans | $ 14,646,000 |  | $ 14,646,000 |  |  | $ 20,713,000 |  |
Other industry exposures |  |  | 0 |  |  |  |  |
Interest lost on nonaccrual loans | $ 187,000 | $ 251,000 | $ 673,000 | $ 675,000 |  |  |  |
Number of TDRs | loan | 3 | 6 | 5 | 6 |  |  |  |
Loans modified | loan | 0 | 0 | 0 | 0 |  |  |  |
Financing Receivable, Individually Evaluated for Impairment | $ 13,430,000 | $ 20,682,000 | $ 13,430,000 | $ 20,682,000 |  | 20,254,000 |  |
Proceeds from the sale of mortgage loans |  |  | 155,086,000 | 170,765,000 |  |  |  |
Gain on sale of mortgage loans |  |  | 4,323,000 | 4,171,000 |  |  |  |
Loans held for sale, at fair value | 12,997,000 |  | 12,997,000 |  |  | 14,836,000 |  |
Financing Receivable, Allowance for Credit Losses | 24,413,000 | 23,290,000 | 24,413,000 | 23,290,000 | $ 24,394,000 | 23,116,000 | $ 23,717,000 | $ 21,166,000
FHLB advances, general debt obligations, pledged collateral | 1,100,000,000 |  | 1,100,000,000 |  |  | 1,100,000,000 |  |
Derivative, Fair Value, Net | 313,000 |  | 313,000 |  |  | 278,000 |  |
Unrealized Gain (Loss) on Derivatives | 60,000 | 226,000 | 283,000 | 610,000 |  |  |  |
Loans |  |  |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |  |  |
Loans restructured due to credit difficulties that are now performing | 5,200,000 |  | 5,200,000 |  |  | 4,300,000 |  |
Financing receivables impaired TDR non-performing | 1,300,000 |  | 1,300,000 |  |  | 1,400,000 |  |
Residential Real Estate |  |  |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |  |  |
Non-Accrual Loans | 4,465,000 |  | 4,465,000 |  |  | 3,945,000 |  |
Financing Receivable, Individually Evaluated for Impairment | 4,792,000 | 4,551,000 | 4,792,000 | 4,551,000 |  | 4,348,000 |  |
Mortgage Loans in Process of Foreclosure, Amount | 2,200,000 |  | 2,200,000 |  |  | 1,400,000 |  |
Financing Receivable, Allowance for Credit Losses | 4,542,000 | 4,595,000 | 4,542,000 | 4,595,000 | 4,481,000 | 4,160,000 | 4,431,000 | 4,545,000
Commercial Real Estate |  |  |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |  |  |
Non-Accrual Loans | 5,887,000 |  | 5,887,000 |  |  | 12,849,000 |  |
Financing Receivable, Individually Evaluated for Impairment | 6,373,000 | 13,286,000 | 6,373,000 | 13,286,000 |  | 13,317,000 |  |
Financing Receivable, Allowance for Credit Losses | 12,796,000 | 12,580,000 | 12,796,000 | 12,580,000 | 12,848,000 | 12,154,000 | 11,559,000 | 10,432,000
Commercial |  |  |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |  |  |
Non-Accrual Loans | 1,830,000 |  | 1,830,000 |  |  | 2,088,000 |  |
Financing Receivable, Individually Evaluated for Impairment | 1,842,000 | 2,243,000 | 1,842,000 | 2,243,000 |  | 2,028,000 |  |
Financing Receivable, Allowance for Credit Losses | 4,221,000 | 3,283,000 | 4,221,000 | 3,283,000 | 4,275,000 | 3,755,000 | 4,558,000 | 3,241,000
Home Equity |  |  |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |  |  |
Non-Accrual Loans | 1,626,000 |  | 1,626,000 |  |  | 1,620,000 |  |
Financing Receivable, Individually Evaluated for Impairment | 423,000 | 489,000 | 423,000 | 489,000 |  | 457,000 |  |
Financing Receivable, Allowance for Credit Losses | 2,177,000 | 2,567,000 | 2,177,000 | 2,567,000 | 2,094,000 | 2,194,000 | 2,946,000 | 2,731,000
Consumer |  |  |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |  |  |
Non-Accrual Loans | 0 |  | 0 |  |  | 4,000 |  |
Financing Receivable, Individually Evaluated for Impairment | 0 | 7,000 | 0 | 7,000 |  | 7,000 |  |
Financing Receivable, Allowance for Credit Losses | 195,000 | 162,000 | 195,000 | 162,000 | 182,000 | 181,000 | 193,000 | 193,000
HPFC Portfolio Segment |  |  |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |  |  |
Non-Accrual Loans | 838,000 |  | 838,000 |  |  | 207,000 |  |
Financing Receivable, Individually Evaluated for Impairment | 0 | 106,000 | 0 | 106,000 |  | 97,000 |  |
Financing Receivable, Allowance for Credit Losses | 482,000 | 103,000 | 482,000 | 103,000 | $ 514,000 | 672,000 | $ 30,000 | $ 24,000
Fixed Rate Residential Mortgage |  |  |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |  |  |
Proceeds from the sale of mortgage loans | 59,900,000 | 71,400,000 | 150,800,000 | 166,600,000 |  |  |  |
Gain on sale of mortgage loans | 1,600,000 | 2,000,000 | 4,300,000 | 4,200,000 |  |  |  |
Loans held for sale, at fair value | 13,000,000 |  | 13,000,000 |  |  | 15,100,000 |  |
Nonoperating Income (Expense) | Fixed Rate Residential Mortgage |  |  |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |  |  |
Gain on sale of mortgage loans | $ 72,000 | (55,000) | 263,000 | 99,000 |  |  |  |
Unrealized gain (loss) on loans held for sale |  |  | $ 26,000 | 289,000 |  |  |  |
Minimum |  |  |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |  |  |
Financing Receivable, Individually Evaluated for Impairment |  |  |  |  |  | 250,000 |  |
Number of Months | 18 |  | 18 |  |  |  |  |
Minimum | HPFC Portfolio Segment |  |  |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |  |  |
Term to maturity | 7 years |  |  |  |  |  |  |
Maximum |  |  |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |  |  |
Number of Months | 24 |  | 24 |  |  |  |  |
Maximum | HPFC Portfolio Segment |  |  |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |  |  |
Term to maturity | 10 years |  |  |  |  |  |  |
Non-Residential Building Operators Industry Sector | Loan Concentration Risk | Total Loan Portfolio |  |  |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |  |  |
Concentration risk (percentage) |  |  | 11.00% |  |  |  |  |
Non-Residential Building Operators Industry Sector | Loan Concentration Risk | Commercial Real Estate |  |  |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |  |  |
Concentration risk (percentage) |  |  | 27.00% |  |  |  |  |
Substandard (Grade 8) | Minimum |  |  |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |  |  |
Financing Receivable, Individually Evaluated for Impairment | $ 500,000 |  | $ 500,000 |  |  |  |  |
Forward Contracts [Member] |  |  |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |  |  |
Derivative, Fair Value, Net | 313,000 |  | 313,000 |  |  | $ 278,000 |  |
Unrealized Gain (Loss) on Derivatives | $ 16,000 | $ 0 | $ 35,000 | $ 0 |  |  |  |

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