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LOANS, Loan Summary (Details) - USD ($) $ in Thousands | 6 Months Ended |  |  |  |  |
--- | --- | --- | --- | --- | --- | ---
Jun. 30, 2018 | Mar. 31, 2018 | Dec. 31, 2017 | Jun. 30, 2017 | Mar. 31, 2017 | Dec. 31, 2016
Loans receivable, net [Abstract] |  |  |  |  |  |
Gross loans, including deferred origination costs | $ 6,238,009 |  | $ 6,256,757 |  |  |
Allowance for loan losses | (49,618) | $ (48,103) | (47,583) | $ (47,451) | $ (47,096) | $ (47,233)
Net loans | 6,188,391 |  | 6,209,174 |  |  |
Credit impaired acquired loans, total balance due | 7,900 |  | 13,400 |  |  |
Accretable discount related to credit impaired acquired loans [Roll forward] |  |  |  |  |  |
Beginning Balance | 976 |  |  |  |  |
Accretion recognized, year-to-date | (688) |  |  |  |  |
Net reclassification between accretable and non-accretable | 326 |  |  |  |  |
Ending Balance | 614 |  |  |  |  |
Business Lending [Member] |  |  |  |  |  |
Loans receivable, net [Abstract] |  |  |  |  |  |
Gross loans, including deferred origination costs | $ 2,384,629 |  | 2,424,223 |  |  |
Consumer Mortgage [Member] | Minimum [Member] |  |  |  |  |  |
Loans receivable, net [Abstract] |  |  |  |  |  |
Typical contract term | 10 years |  |  |  |  |
Consumer Mortgage [Member] | Maximum [Member] |  |  |  |  |  |
Loans receivable, net [Abstract] |  |  |  |  |  |
Typical contract term | 30 years |  |  |  |  |
Home Equity [Member] | Maximum [Member] |  |  |  |  |  |
Loans receivable, net [Abstract] |  |  |  |  |  |
Typical contract term | 30 years |  |  |  |  |
Commercial Portfolio Segment [Member] | Business Lending [Member] |  |  |  |  |  |
Loans receivable, net [Abstract] |  |  |  |  |  |
Gross loans, including deferred origination costs | $ 2,384,629 |  | 2,424,223 |  |  |
Allowance for loan losses | (10,473) |  | (10,465) | (10,197) |  | (10,094)
Commercial Portfolio Segment [Member] | Consumer Mortgage [Member] |  |  |  |  |  |
Loans receivable, net [Abstract] |  |  |  |  |  |
Allowance for loan losses | (10,473) | (10,382) |  | (10,197) | (10,149) |
Residential Portfolio Segment [Member] | Business Lending [Member] |  |  |  |  |  |
Loans receivable, net [Abstract] |  |  |  |  |  |
Allowance for loan losses | (18,439) | (17,607) |  | (17,230) | (16,857) |
Residential Portfolio Segment [Member] | Consumer Mortgage [Member] |  |  |  |  |  |
Loans receivable, net [Abstract] |  |  |  |  |  |
Gross loans, including deferred origination costs | 2,210,051 |  | 2,220,298 |  |  |
Allowance for loan losses | (18,439) |  | (17,257) | (17,230) |  | (17,220)
Consumer Portfolio Segment [Member] | Consumer Indirect [Member] |  |  |  |  |  |
Loans receivable, net [Abstract] |  |  |  |  |  |
Gross loans, including deferred origination costs | 1,063,679 |  | 1,011,978 |  |  |
Allowance for loan losses | (14,424) | (13,698) | (13,468) | (13,918) | (13,996) | (13,782)
Consumer Portfolio Segment [Member] | Consumer Direct [Member] |  |  |  |  |  |
Loans receivable, net [Abstract] |  |  |  |  |  |
Gross loans, including deferred origination costs | 181,217 |  | 179,929 |  |  |
Allowance for loan losses | (3,164) | (2,984) | (3,039) | (2,945) | (2,852) | (2,979)
Consumer Portfolio Segment [Member] | Home Equity [Member] |  |  |  |  |  |
Loans receivable, net [Abstract] |  |  |  |  |  |
Gross loans, including deferred origination costs | 398,433 |  | 420,329 |  |  |
Allowance for loan losses | $ (2,015) | $ (2,040) | $ (2,107) | $ (2,242) | $ (2,359) | $ (2,399)

X
- Definition The undiscounted sum of all amounts, including amounts deemed principal, interest, fees, penalties, and other under the loan, owed to the investor at the reporting date, whether or not currently due and whether or not any such amounts have been written or charged off by the investor. This relates to loans not accounted for as debt securities, with evidence of deterioration of credit quality since origination that were acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable. + References No definition available. + Details
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- Definition The typical original contract term of financial receivable, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
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- Definition Amount of the excess of a loan's cash flows expected to be collected over the investor's initial investment in acquired loans not accounted for as debt securities with evidence of deterioration of credit quality. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 30 -Section 15 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=82894507&loc=d3e13503-111538 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=82894903&loc=d3e15032-111544 + Details
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- Definition Amount of accretion recognized for the excess of a loan's cash flows expected to be collected over the investor's initial investment in acquired loans not accounted for as debt securities, with evidence of deterioration of credit quality. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 30 -Section 15 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=82894507&loc=d3e13503-111538 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=82894903&loc=d3e15032-111544 + Details
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- Definition Amount of increase of reclassification from nonaccretable difference to the excess of a loan's cash flows expected to be collected over the investor's initial investment in acquired loans not accounted for as debt securities with evidence of deterioration of credit quality. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 30 -Section 15 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=82894507&loc=d3e13503-111538 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=82894903&loc=d3e15032-111544 + Details
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- Definition Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.7(d)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (g) -URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (b)(1)(ii) -URI http://asc.fasb.org/extlink&oid=82894903&loc=d3e15032-111544 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524 Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section S99 -Paragraph 4 -Subparagraph (SAB Topic 6.L.1) -URI http://asc.fasb.org/extlink&oid=27010918&loc=d3e74567-122707 + Details
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