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LOANS, Amount of Business Lending Loans by Credit Quality Category (Details) - USD ($) $ in Thousands | Mar. 31, 2020 | Dec. 31, 2019
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Term Loans Amortized Cost Basis by Origination Year [Abstract] |  |
Loans | $ 6,866,092 | $ 6,890,543
Legacy Loans [Member] |  |
Term Loans Amortized Cost Basis by Origination Year [Abstract] |  |
Loans |  | 5,450,592
Acquired Loans [Member] |  |
Term Loans Amortized Cost Basis by Origination Year [Abstract] |  |
Loans |  | 1,439,951
Business Lending [Member] |  |
Term Loans Amortized Cost Basis by Origination Year [Abstract] |  |
2020 | 86,094 |
2019 | 400,504 |
2018 | 357,713 |
2017 | 262,226 |
2016 | 293,477 |
Prior | 718,597 |
Revolving loans amortized cost basis | 670,519 |
Total | 2,789,130 |
Loans |  | 2,775,876
Business Lending [Member] | Legacy Loans [Member] |  |
Term Loans Amortized Cost Basis by Origination Year [Abstract] |  |
Loans |  | 1,856,585
Business Lending [Member] | Acquired Loans [Member] |  |
Term Loans Amortized Cost Basis by Origination Year [Abstract] |  |
Loans |  | 919,291
Business Lending [Member] | Pass [Member] |  |
Term Loans Amortized Cost Basis by Origination Year [Abstract] |  |
2020 | 81,301 |
2019 | 386,281 |
2018 | 333,585 |
2017 | 239,020 |
2016 | 276,171 |
Prior | 606,390 |
Revolving loans amortized cost basis | 593,830 |
Total | 2,516,578 |
Loans |  | 2,487,973
Business Lending [Member] | Pass [Member] | Legacy Loans [Member] |  |
Term Loans Amortized Cost Basis by Origination Year [Abstract] |  |
Loans |  | 1,655,280
Business Lending [Member] | Pass [Member] | Acquired Loans [Member] |  |
Term Loans Amortized Cost Basis by Origination Year [Abstract] |  |
Loans |  | 832,693
Business Lending [Member] | Special Mention [Member] |  |
Term Loans Amortized Cost Basis by Origination Year [Abstract] |  |
2020 | 4,128 |
2019 | 12,290 |
2018 | 6,887 |
2017 | 13,213 |
2016 | 4,516 |
Prior | 52,457 |
Revolving loans amortized cost basis | 31,223 |
Total | 124,714 |
Loans |  | 144,277
Business Lending [Member] | Special Mention [Member] | Legacy Loans [Member] |  |
Term Loans Amortized Cost Basis by Origination Year [Abstract] |  |
Loans |  | 98,953
Business Lending [Member] | Special Mention [Member] | Acquired Loans [Member] |  |
Term Loans Amortized Cost Basis by Origination Year [Abstract] |  |
Loans |  | 45,324
Business Lending [Member] | Classified [Member] |  |
Term Loans Amortized Cost Basis by Origination Year [Abstract] |  |
2020 | 665 |
2019 | 1,933 |
2018 | 17,241 |
2017 | 9,993 |
2016 | 12,790 |
Prior | 59,750 |
Revolving loans amortized cost basis | 45,466 |
Total | 147,838 |
Loans |  | 131,829
Business Lending [Member] | Classified [Member] | Legacy Loans [Member] |  |
Term Loans Amortized Cost Basis by Origination Year [Abstract] |  |
Loans |  | 102,352
Business Lending [Member] | Classified [Member] | Acquired Loans [Member] |  |
Term Loans Amortized Cost Basis by Origination Year [Abstract] |  |
Loans |  | 29,477
Business Lending [Member] | Doubtful [Member] |  |
Term Loans Amortized Cost Basis by Origination Year [Abstract] |  |
2020 | 0 |
2019 | 0 |
2018 | 0 |
2017 | 0 |
2016 | 0 |
Prior | 0 |
Revolving loans amortized cost basis | 0 |
Total | 0 |
Loans |  | 0
Business Lending [Member] | Doubtful [Member] | Legacy Loans [Member] |  |
Term Loans Amortized Cost Basis by Origination Year [Abstract] |  |
Loans |  | 0
Business Lending [Member] | Doubtful [Member] | Acquired Loans [Member] |  |
Term Loans Amortized Cost Basis by Origination Year [Abstract] |  |
Loans |  | 0
Business Lending [Member] | Acquired Impaired [Member] |  |
Term Loans Amortized Cost Basis by Origination Year [Abstract] |  |
Loans |  | 11,797
Business Lending [Member] | Acquired Impaired [Member] | Legacy Loans [Member] |  |
Term Loans Amortized Cost Basis by Origination Year [Abstract] |  |
Loans |  | 0
Business Lending [Member] | Acquired Impaired [Member] | Acquired Loans [Member] |  |
Term Loans Amortized Cost Basis by Origination Year [Abstract] |  |
Loans |  | 11,797
All Other Loans [Member] | Legacy Loans [Member] |  |
Term Loans Amortized Cost Basis by Origination Year [Abstract] |  |
Loans |  | 3,594,007
All Other Loans [Member] | Acquired Loans [Member] |  |
Term Loans Amortized Cost Basis by Origination Year [Abstract] |  |
Loans |  | 520,660
All Other Loans [Member] | Performing [Member] | Legacy Loans [Member] |  |
Term Loans Amortized Cost Basis by Origination Year [Abstract] |  |
Loans |  | 3,579,851
All Other Loans [Member] | Performing [Member] | Acquired Loans [Member] |  |
Term Loans Amortized Cost Basis by Origination Year [Abstract] |  |
Loans |  | 517,264
All Other Loans [Member] | Nonperforming [Member] | Legacy Loans [Member] |  |
Term Loans Amortized Cost Basis by Origination Year [Abstract] |  |
Loans |  | 14,156
All Other Loans [Member] | Nonperforming [Member] | Acquired Loans [Member] |  |
Term Loans Amortized Cost Basis by Origination Year [Abstract] |  |
Loans |  | 3,396
Consumer Mortgage [Member] |  |
Term Loans Amortized Cost Basis by Origination Year [Abstract] |  |
2020 | 70,116 |
2019 | 363,967 |
2018 | 284,358 |
2017 | 279,769 |
2016 | 283,193 |
Prior | 1,130,604 |
Revolving loans amortized cost basis | 12,649 |
Total | 2,424,656 |
Consumer Mortgage [Member] | Legacy Loans [Member] |  |
Term Loans Amortized Cost Basis by Origination Year [Abstract] |  |
Loans |  | 1,996,716
Consumer Mortgage [Member] | Acquired Loans [Member] |  |
Term Loans Amortized Cost Basis by Origination Year [Abstract] |  |
Loans |  | 434,186
Consumer Mortgage [Member] | Performing [Member] | Legacy Loans [Member] |  |
Term Loans Amortized Cost Basis by Origination Year [Abstract] |  |
Loans |  | 1,984,533
Consumer Mortgage [Member] | Performing [Member] | Acquired Loans [Member] |  |
Term Loans Amortized Cost Basis by Origination Year [Abstract] |  |
Loans |  | 431,523
Consumer Mortgage [Member] | Nonperforming [Member] | Legacy Loans [Member] |  |
Term Loans Amortized Cost Basis by Origination Year [Abstract] |  |
Loans |  | 12,183
Consumer Mortgage [Member] | Nonperforming [Member] | Acquired Loans [Member] |  |
Term Loans Amortized Cost Basis by Origination Year [Abstract] |  |
Loans |  | 2,663
Consumer Mortgage [Member] | FICO AB [Member] |  |
Term Loans Amortized Cost Basis by Origination Year [Abstract] |  |
2020 | 47,527 |
2019 | 252,841 |
2018 | 194,765 |
2017 | 190,615 |
2016 | 187,447 |
Prior | 654,176 |
Revolving loans amortized cost basis | 0 |
Total | 1,527,371 |
Consumer Mortgage [Member] | FICO AB [Member] | Performing [Member] |  |
Term Loans Amortized Cost Basis by Origination Year [Abstract] |  |
2020 | 47,527 |
2019 | 252,841 |
2018 | 194,612 |
2017 | 190,316 |
2016 | 187,254 |
Prior | 651,314 |
Revolving loans amortized cost basis | 0 |
Total | 1,523,864 |
Consumer Mortgage [Member] | FICO AB [Member] | Nonperforming [Member] |  |
Term Loans Amortized Cost Basis by Origination Year [Abstract] |  |
2020 | 0 |
2019 | 0 |
2018 | 153 |
2017 | 299 |
2016 | 193 |
Prior | 2,862 |
Revolving loans amortized cost basis | 0 |
Total | 3,507 |
Consumer Mortgage [Member] | FICO CDE [Member] |  |
Term Loans Amortized Cost Basis by Origination Year [Abstract] |  |
2020 | 22,589 |
2019 | 111,126 |
2018 | 89,593 |
2017 | 89,154 |
2016 | 95,746 |
Prior | 476,428 |
Revolving loans amortized cost basis | 12,649 |
Total | 897,285 |
Consumer Mortgage [Member] | FICO CDE [Member] | Performing [Member] |  |
Term Loans Amortized Cost Basis by Origination Year [Abstract] |  |
2020 | 22,589 |
2019 | 111,126 |
2018 | 89,451 |
2017 | 88,630 |
2016 | 94,419 |
Prior | 467,433 |
Revolving loans amortized cost basis | 12,649 |
Total | 886,297 |
Consumer Mortgage [Member] | FICO CDE [Member] | Nonperforming [Member] |  |
Term Loans Amortized Cost Basis by Origination Year [Abstract] |  |
2020 | 0 |
2019 | 0 |
2018 | 142 |
2017 | 524 |
2016 | 1,327 |
Prior | 8,995 |
Revolving loans amortized cost basis | 0 |
Total | 10,988 |
Consumer Indirect [Member] |  |
Term Loans Amortized Cost Basis by Origination Year [Abstract] |  |
2020 | 74,581 |
2019 | 397,540 |
2018 | 284,977 |
2017 | 133,465 |
2016 | 102,948 |
Prior | 94,368 |
Revolving loans amortized cost basis | 0 |
Total | 1,087,879 |
Consumer Indirect [Member] | Legacy Loans [Member] |  |
Term Loans Amortized Cost Basis by Origination Year [Abstract] |  |
Loans |  | 1,107,308
Consumer Indirect [Member] | Acquired Loans [Member] |  |
Term Loans Amortized Cost Basis by Origination Year [Abstract] |  |
Loans |  | 5,754
Consumer Indirect [Member] | Performing [Member] |  |
Term Loans Amortized Cost Basis by Origination Year [Abstract] |  |
2020 | 74,581 |
2019 | 397,442 |
2018 | 284,899 |
2017 | 133,402 |
2016 | 102,849 |
Prior | 94,288 |
Revolving loans amortized cost basis | 0 |
Total | 1,087,461 |
Consumer Indirect [Member] | Performing [Member] | Legacy Loans [Member] |  |
Term Loans Amortized Cost Basis by Origination Year [Abstract] |  |
Loans |  | 1,107,183
Consumer Indirect [Member] | Performing [Member] | Acquired Loans [Member] |  |
Term Loans Amortized Cost Basis by Origination Year [Abstract] |  |
Loans |  | 5,723
Consumer Indirect [Member] | Nonperforming [Member] |  |
Term Loans Amortized Cost Basis by Origination Year [Abstract] |  |
2020 | 0 |
2019 | 98 |
2018 | 78 |
2017 | 63 |
2016 | 99 |
Prior | 80 |
Revolving loans amortized cost basis | 0 |
Total | 418 |
Consumer Indirect [Member] | Nonperforming [Member] | Legacy Loans [Member] |  |
Term Loans Amortized Cost Basis by Origination Year [Abstract] |  |
Loans |  | 125
Consumer Indirect [Member] | Nonperforming [Member] | Acquired Loans [Member] |  |
Term Loans Amortized Cost Basis by Origination Year [Abstract] |  |
Loans |  | 31
Consumer Direct [Member] |  |
Term Loans Amortized Cost Basis by Origination Year [Abstract] |  |
2020 | 20,080 |
2019 | 66,320 |
2018 | 42,400 |
2017 | 21,210 |
2016 | 11,052 |
Prior | 9,121 |
Revolving loans amortized cost basis | 7,661 |
Total | 177,844 |
Consumer Direct [Member] | Legacy Loans [Member] |  |
Term Loans Amortized Cost Basis by Origination Year [Abstract] |  |
Loans |  | 175,976
Consumer Direct [Member] | Acquired Loans [Member] |  |
Term Loans Amortized Cost Basis by Origination Year [Abstract] |  |
Loans |  | 8,402
Consumer Direct [Member] | Performing [Member] |  |
Term Loans Amortized Cost Basis by Origination Year [Abstract] |  |
2020 | 20,080 |
2019 | 66,306 |
2018 | 42,399 |
2017 | 21,144 |
2016 | 11,049 |
Prior | 9,121 |
Revolving loans amortized cost basis | 7,631 |
Total | 177,730 |
Consumer Direct [Member] | Performing [Member] | Legacy Loans [Member] |  |
Term Loans Amortized Cost Basis by Origination Year [Abstract] |  |
Loans |  | 175,900
Consumer Direct [Member] | Performing [Member] | Acquired Loans [Member] |  |
Term Loans Amortized Cost Basis by Origination Year [Abstract] |  |
Loans |  | 8,350
Consumer Direct [Member] | Nonperforming [Member] |  |
Term Loans Amortized Cost Basis by Origination Year [Abstract] |  |
2020 | 0 |
2019 | 14 |
2018 | 1 |
2017 | 66 |
2016 | 3 |
Prior | 0 |
Revolving loans amortized cost basis | 30 |
Total | 114 |
Consumer Direct [Member] | Nonperforming [Member] | Legacy Loans [Member] |  |
Term Loans Amortized Cost Basis by Origination Year [Abstract] |  |
Loans |  | 76
Consumer Direct [Member] | Nonperforming [Member] | Acquired Loans [Member] |  |
Term Loans Amortized Cost Basis by Origination Year [Abstract] |  |
Loans |  | 52
Home Equity [Member] |  |
Term Loans Amortized Cost Basis by Origination Year [Abstract] |  |
2020 | 14,521 |
2019 | 51,149 |
2018 | 28,687 |
2017 | 23,267 |
2016 | 19,436 |
Prior | 35,856 |
Revolving loans amortized cost basis | 213,667 |
Total | 386,583 |
Home Equity [Member] | Legacy Loans [Member] |  |
Term Loans Amortized Cost Basis by Origination Year [Abstract] |  |
Loans |  | 314,007
Home Equity [Member] | Acquired Loans [Member] |  |
Term Loans Amortized Cost Basis by Origination Year [Abstract] |  |
Loans |  | 72,318
Home Equity [Member] | Performing [Member] |  |
Term Loans Amortized Cost Basis by Origination Year [Abstract] |  |
2020 | 14,521 |
2019 | 51,149 |
2018 | 28,687 |
2017 | 23,194 |
2016 | 19,318 |
Prior | 35,395 |
Revolving loans amortized cost basis | 212,069 |
Total | 384,333 |
Home Equity [Member] | Performing [Member] | Legacy Loans [Member] |  |
Term Loans Amortized Cost Basis by Origination Year [Abstract] |  |
Loans |  | 312,235
Home Equity [Member] | Performing [Member] | Acquired Loans [Member] |  |
Term Loans Amortized Cost Basis by Origination Year [Abstract] |  |
Loans |  | 71,668
Home Equity [Member] | Nonperforming [Member] |  |
Term Loans Amortized Cost Basis by Origination Year [Abstract] |  |
2020 | 0 |
2019 | 0 |
2018 | 0 |
2017 | 73 |
2016 | 118 |
Prior | 461 |
Revolving loans amortized cost basis | 1,598 |
Total | $ 2,250 |
Home Equity [Member] | Nonperforming [Member] | Legacy Loans [Member] |  |
Term Loans Amortized Cost Basis by Origination Year [Abstract] |  |
Loans |  | 1,772
Home Equity [Member] | Nonperforming [Member] | Acquired Loans [Member] |  |
Term Loans Amortized Cost Basis by Origination Year [Abstract] |  |
Loans |  | $ 650

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