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LOANS, Amount of Business Lending Loans by Credit Quality Category (Details) - USD ($) $ in Thousands | Dec. 31, 2017 | Dec. 31, 2016
--- | --- | ---
Financing Receivable, Recorded Investment [Line Items] |  |
Loans | $ 6,256,757 | $ 4,948,562
Legacy Loan [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans | 4,619,663 | 4,453,202
Acquired Loans [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans | 1,637,094 | 495,360
Business Lending [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans | 2,424,223 | 1,490,076
Business Lending [Member] | Legacy Loan [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans | 1,376,599 | 1,277,666
Business Lending [Member] | Acquired Loans [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans | 1,047,624 | 212,410
Business Lending [Member] | Pass [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans | 2,134,137 | 1,213,170
Business Lending [Member] | Pass [Member] | Legacy Loan [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans | 1,170,156 | 1,051,005
Business Lending [Member] | Pass [Member] | Acquired Loans [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans | 963,981 | 162,165
Business Lending [Member] | Special Mention [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans | 166,397 | 165,292
Business Lending [Member] | Special Mention [Member] | Legacy Loan [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans | 129,076 | 135,602
Business Lending [Member] | Special Mention [Member] | Acquired Loans [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans | 37,321 | 29,690
Business Lending [Member] | Classified [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans | 111,995 | 105,587
Business Lending [Member] | Classified [Member] | Legacy Loan [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans | 77,367 | 90,585
Business Lending [Member] | Classified [Member] | Acquired Loans [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans | 34,628 | 15,002
Business Lending [Member] | Doubtful [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans | 1,579 | 474
Business Lending [Member] | Doubtful [Member] | Legacy Loan [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans | 0 | 474
Business Lending [Member] | Doubtful [Member] | Acquired Loans [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans | 1,579 | 0
Business Lending [Member] | Acquired Impaired [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans | 10,115 | 5,553
Business Lending [Member] | Acquired Impaired [Member] | Legacy Loan [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans | 0 | 0
Business Lending [Member] | Acquired Impaired [Member] | Acquired Loans [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans | 10,115 | 5,553
All Other Loans [Member] | Legacy Loan [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans | 3,243,064 | 3,175,536
All Other Loans [Member] | Acquired Loans [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans | 589,470 | 282,950
All Other Loans [Member] | Performing [Member] | Legacy Loan [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans | 3,229,051 | 3,160,929
All Other Loans [Member] | Performing [Member] | Acquired Loans [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans | 584,874 | 279,070
All Other Loans [Member] | Nonperforming [Member] | Legacy Loan [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans | 14,013 | 14,607
All Other Loans [Member] | Nonperforming [Member] | Acquired Loans [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans | 4,596 | 3,880
Consumer Mortgage [Member] | Legacy Loan [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans | 1,754,609 | 1,659,760
Consumer Mortgage [Member] | Acquired Loans [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans | 465,689 | 159,941
Consumer Mortgage [Member] | Performing [Member] | Legacy Loan [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans | 1,742,387 | 1,647,228
Consumer Mortgage [Member] | Performing [Member] | Acquired Loans [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans | 462,597 | 157,404
Consumer Mortgage [Member] | Nonperforming [Member] | Legacy Loan [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans | 12,222 | 12,532
Consumer Mortgage [Member] | Nonperforming [Member] | Acquired Loans [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans | 3,092 | 2,537
Consumer Indirect [Member] | Legacy Loan [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans | 991,836 | 1,014,825
Consumer Indirect [Member] | Acquired Loans [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans | 20,142 | 30,147
Consumer Indirect [Member] | Performing [Member] | Legacy Loan [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans | 991,541 | 1,014,659
Consumer Indirect [Member] | Performing [Member] | Acquired Loans [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans | 20,134 | 30,144
Consumer Indirect [Member] | Nonperforming [Member] | Legacy Loan [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans | 295 | 166
Consumer Indirect [Member] | Nonperforming [Member] | Acquired Loans [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans | 8 | 3
Consumer Direct [Member] | Legacy Loan [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans | 174,479 | 181,922
Consumer Direct [Member] | Acquired Loans [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans | 5,450 | 9,893
Consumer Direct [Member] | Performing [Member] | Legacy Loan [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans | 174,431 | 181,864
Consumer Direct [Member] | Performing [Member] | Acquired Loans [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans | 5,450 | 9,893
Consumer Direct [Member] | Nonperforming [Member] | Legacy Loan [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans | 48 | 58
Consumer Direct [Member] | Nonperforming [Member] | Acquired Loans [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans | 0 | 0
Home Equity [Member] | Legacy Loan [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans | 322,140 | 319,029
Home Equity [Member] | Acquired Loans [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans | 98,189 | 82,969
Home Equity [Member] | Performing [Member] | Legacy Loan [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans | 320,692 | 317,178
Home Equity [Member] | Performing [Member] | Acquired Loans [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans | 96,693 | 81,629
Home Equity [Member] | Nonperforming [Member] | Legacy Loan [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans | 1,448 | 1,851
Home Equity [Member] | Nonperforming [Member] | Acquired Loans [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans | $ 1,496 | $ 1,340

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- Definition Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=82891408&loc=d3e4428-111522 + Details
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