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LOANS, Amount of Business Lending Loans by Credit Quality Category (Details) - USD ($) $ in Thousands | Jun. 30, 2020 | Dec. 31, 2019
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Term Loans Amortized Cost Basis by Origination Year [Abstract] |  |
Loans | $ 7,528,039 | $ 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 | 670,379 |
2019 | 405,722 |
2018 | 395,076 |
2017 | 294,450 |
2016 | 308,151 |
Prior | 746,224 |
Revolving loans amortized cost basis | 635,341 |
Total | 3,455,343 |
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 | 661,019 |
2019 | 390,621 |
2018 | 371,073 |
2017 | 273,598 |
2016 | 274,860 |
Prior | 634,379 |
Revolving loans amortized cost basis | 567,034 |
Total | 3,172,584 |
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 | 6,026 |
2019 | 12,045 |
2018 | 6,641 |
2017 | 12,701 |
2016 | 18,005 |
Prior | 56,168 |
Revolving loans amortized cost basis | 30,485 |
Total | 142,071 |
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 | 3,334 |
2019 | 3,056 |
2018 | 17,362 |
2017 | 8,151 |
2016 | 15,286 |
Prior | 55,677 |
Revolving loans amortized cost basis | 37,822 |
Total | 140,688 |
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 | 158,861 |
2019 | 356,457 |
2018 | 273,486 |
2017 | 269,787 |
2016 | 271,965 |
Prior | 1,087,278 |
Revolving loans amortized cost basis | 10,226 |
Total | 2,428,060 |
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 | 111,491 |
2019 | 247,801 |
2018 | 186,837 |
2017 | 185,472 |
2016 | 178,776 |
Prior | 715,498 |
Revolving loans amortized cost basis | 454 |
Total | 1,626,329 |
Consumer Mortgage [Member] | FICO AB [Member] | Performing [Member] |  |
Term Loans Amortized Cost Basis by Origination Year [Abstract] |  |
2020 | 111,491 |
2019 | 247,646 |
2018 | 186,686 |
2017 | 185,064 |
2016 | 178,459 |
Prior | 712,049 |
Revolving loans amortized cost basis | 454 |
Total | 1,621,849 |
Consumer Mortgage [Member] | FICO AB [Member] | Nonperforming [Member] |  |
Term Loans Amortized Cost Basis by Origination Year [Abstract] |  |
2020 | 0 |
2019 | 155 |
2018 | 151 |
2017 | 408 |
2016 | 317 |
Prior | 3,449 |
Revolving loans amortized cost basis | 0 |
Total | 4,480 |
Consumer Mortgage [Member] | FICO CDE [Member] |  |
Term Loans Amortized Cost Basis by Origination Year [Abstract] |  |
2020 | 47,370 |
2019 | 108,656 |
2018 | 86,649 |
2017 | 84,315 |
2016 | 93,189 |
Prior | 371,780 |
Revolving loans amortized cost basis | 9,772 |
Total | 801,731 |
Consumer Mortgage [Member] | FICO CDE [Member] | Performing [Member] |  |
Term Loans Amortized Cost Basis by Origination Year [Abstract] |  |
2020 | 47,370 |
2019 | 108,296 |
2018 | 85,917 |
2017 | 83,641 |
2016 | 91,733 |
Prior | 362,287 |
Revolving loans amortized cost basis | 9,772 |
Total | 789,016 |
Consumer Mortgage [Member] | FICO CDE [Member] | Nonperforming [Member] |  |
Term Loans Amortized Cost Basis by Origination Year [Abstract] |  |
2020 | 0 |
2019 | 360 |
2018 | 732 |
2017 | 674 |
2016 | 1,456 |
Prior | 9,493 |
Revolving loans amortized cost basis | 0 |
Total | 12,715 |
Consumer Indirect [Member] |  |
Term Loans Amortized Cost Basis by Origination Year [Abstract] |  |
2020 | 135,342 |
2019 | 372,460 |
2018 | 260,805 |
2017 | 118,294 |
2016 | 88,691 |
Prior | 81,273 |
Revolving loans amortized cost basis | 0 |
Total | 1,056,865 |
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 | 135,333 |
2019 | 372,290 |
2018 | 260,629 |
2017 | 118,119 |
2016 | 88,554 |
Prior | 81,194 |
Revolving loans amortized cost basis | 0 |
Total | 1,056,119 |
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 | 9 |
2019 | 170 |
2018 | 176 |
2017 | 175 |
2016 | 137 |
Prior | 79 |
Revolving loans amortized cost basis | 0 |
Total | 746 |
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 | 27,668 |
2019 | 60,989 |
2018 | 38,371 |
2017 | 18,594 |
2016 | 8,888 |
Prior | 7,892 |
Revolving loans amortized cost basis | 6,826 |
Total | 169,228 |
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 | 27,668 |
2019 | 60,954 |
2018 | 38,348 |
2017 | 18,528 |
2016 | 8,888 |
Prior | 7,892 |
Revolving loans amortized cost basis | 6,824 |
Total | 169,102 |
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 | 35 |
2018 | 23 |
2017 | 66 |
2016 | 0 |
Prior | 0 |
Revolving loans amortized cost basis | 2 |
Total | 126 |
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 | 31,060 |
2019 | 53,585 |
2018 | 31,703 |
2017 | 26,759 |
2016 | 21,996 |
Prior | 41,082 |
Revolving loans amortized cost basis | 212,358 |
Total | 418,543 |
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 | 31,060 |
2019 | 53,585 |
2018 | 31,703 |
2017 | 26,694 |
2016 | 21,831 |
Prior | 40,438 |
Revolving loans amortized cost basis | 210,726 |
Total | 416,037 |
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 | 65 |
2016 | 165 |
Prior | 644 |
Revolving loans amortized cost basis | 1,632 |
Total | $ 2,506 |
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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