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LOANS AND ALLOWANCE FOR CREDIT LOSSES - Amount of Business Lending Loans by Credit Quality Categories (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2023 | Sep. 30, 2022 | Sep. 30, 2023 | Sep. 30, 2022 | Dec. 31, 2022
Term loans amortized cost basis by origination year |  |  |  |  |
Total Loans | $ 9,450,066 |  | $ 9,450,066 |  | $ 8,809,394
Total Loans | 2,942 | $ 2,688 | 8,930 | $ 6,991 |
Legacy Loan |  |  |  |  |
Term loans amortized cost basis by origination year |  |  |  |  |
Total Loans | 9,450,066 |  | 9,450,066 |  | 8,809,394
Business lending |  |  |  |  |
Term loans amortized cost basis by origination year |  |  |  |  |
Year One | 311,009 |  | 311,009 |  | 752,160
Year Two | 665,399 |  | 665,399 |  | 379,524
Year Three | 346,496 |  | 346,496 |  | 237,510
Year Four | 213,880 |  | 213,880 |  | 253,692
Year Five | 230,642 |  | 230,642 |  | 195,296
Prior | 790,502 |  | 790,502 |  | 688,510
Revolving Loans Amortized Cost Basis | 758,852 |  | 758,852 |  | 686,761
Revolving Loans Converted to Term | 598,155 |  | 598,155 |  | 452,212
Total Loans | 3,914,935 |  | 3,914,935 |  | 3,645,665
Year One |  |  | 0 |  |
Year Two |  |  | 160 |  |
Year Three |  |  | 0 |  |
Year Four |  |  | 0 |  |
Year Five |  |  | 0 |  |
Prior |  |  | 0 |  |
Revolving Loans Amortized Cost Basis |  |  | 458 |  |
Revolving Loans Converted to Term |  |  | 0 |  |
Total Loans |  |  | 618 |  |
Business lending | Pass |  |  |  |  |
Term loans amortized cost basis by origination year |  |  |  |  |
Year One | 290,903 |  | 290,903 |  | 747,573
Year Two | 659,190 |  | 659,190 |  | 373,913
Year Three | 325,480 |  | 325,480 |  | 232,591
Year Four | 205,591 |  | 205,591 |  | 246,820
Year Five | 224,256 |  | 224,256 |  | 168,468
Prior | 710,607 |  | 710,607 |  | 604,745
Revolving Loans Amortized Cost Basis | 721,951 |  | 721,951 |  | 646,771
Revolving Loans Converted to Term | 526,358 |  | 526,358 |  | 401,531
Total Loans | 3,664,336 |  | 3,664,336 |  | 3,422,412
Business lending | Special Mention |  |  |  |  |
Term loans amortized cost basis by origination year |  |  |  |  |
Year One | 19,647 |  | 19,647 |  | 2,787
Year Two | 3,463 |  | 3,463 |  | 4,836
Year Three | 18,359 |  | 18,359 |  | 3,781
Year Four | 2,655 |  | 2,655 |  | 3,676
Year Five | 3,523 |  | 3,523 |  | 14,593
Prior | 58,407 |  | 58,407 |  | 45,627
Revolving Loans Amortized Cost Basis | 22,473 |  | 22,473 |  | 29,403
Revolving Loans Converted to Term | 43,473 |  | 43,473 |  | 29,975
Total Loans | 172,000 |  | 172,000 |  | 134,678
Business lending | Classified |  |  |  |  |
Term loans amortized cost basis by origination year |  |  |  |  |
Year One | 459 |  | 459 |  | 1,800
Year Two | 2,746 |  | 2,746 |  | 775
Year Three | 2,657 |  | 2,657 |  | 1,138
Year Four | 5,146 |  | 5,146 |  | 3,196
Year Five | 2,863 |  | 2,863 |  | 12,235
Prior | 21,488 |  | 21,488 |  | 38,138
Revolving Loans Amortized Cost Basis | 14,428 |  | 14,428 |  | 10,587
Revolving Loans Converted to Term | 28,324 |  | 28,324 |  | 20,706
Total Loans | 78,111 |  | 78,111 |  | 88,575
Business lending | Doubtful |  |  |  |  |
Term loans amortized cost basis by origination year |  |  |  |  |
Year One | 0 |  | 0 |  | 0
Year Two | 0 |  | 0 |  | 0
Year Three | 0 |  | 0 |  | 0
Year Four | 488 |  | 488 |  | 0
Year Five | 0 |  | 0 |  | 0
Prior | 0 |  | 0 |  | 0
Revolving Loans Amortized Cost Basis | 0 |  | 0 |  | 0
Revolving Loans Converted to Term | 0 |  | 0 |  | 0
Total Loans | 488 |  | 488 |  | 0
Consumer mortgage |  |  |  |  |
Term loans amortized cost basis by origination year |  |  |  |  |
Year One | 368,161 |  | 368,161 |  | 539,679
Year Two | 513,939 |  | 513,939 |  | 672,042
Year Three | 637,522 |  | 637,522 |  | 332,352
Year Four | 310,962 |  | 310,962 |  | 255,089
Year Five | 236,244 |  | 236,244 |  | 157,548
Prior | 991,831 |  | 991,831 |  | 944,971
Revolving Loans Amortized Cost Basis | 28,997 |  | 28,997 |  | 28,989
Revolving Loans Converted to Term | 109,108 |  | 109,108 |  | 81,805
Total Loans | 3,196,764 |  | 3,196,764 |  | 3,012,475
Year One |  |  | 0 |  |
Year Two |  |  | 0 |  |
Year Three |  |  | 0 |  |
Year Five |  |  | 85 |  |
Prior |  |  | 281 |  |
Revolving Loans Amortized Cost Basis |  |  | 0 |  |
Revolving Loans Converted to Term |  |  | 0 |  |
Total Loans |  |  | 366 |  |
Consumer mortgage | FICO AB |  |  |  |  |
Term loans amortized cost basis by origination year |  |  |  |  |
Year One | 274,173 |  | 274,173 |  | 379,171
Year Two | 358,711 |  | 358,711 |  | 492,806
Year Three | 466,935 |  | 466,935 |  | 218,462
Year Four | 204,268 |  | 204,268 |  | 174,126
Year Five | 160,829 |  | 160,829 |  | 100,560
Prior | 634,415 |  | 634,415 |  | 608,605
Revolving Loans Amortized Cost Basis | 0 |  | 0 |  | 954
Revolving Loans Converted to Term | 79,816 |  | 79,816 |  | 59,088
Total Loans | 2,179,147 |  | 2,179,147 |  | 2,033,772
Consumer mortgage | FICO AB | Performing |  |  |  |  |
Term loans amortized cost basis by origination year |  |  |  |  |
Year One | 274,173 |  | 274,173 |  | 379,171
Year Two | 358,296 |  | 358,296 |  | 492,731
Year Three | 466,228 |  | 466,228 |  | 217,889
Year Four | 203,702 |  | 203,702 |  | 173,942
Year Five | 160,654 |  | 160,654 |  | 100,161
Prior | 629,208 |  | 629,208 |  | 604,258
Revolving Loans Amortized Cost Basis | 0 |  | 0 |  | 954
Revolving Loans Converted to Term | 79,618 |  | 79,618 |  | 58,639
Total Loans | 2,171,879 |  | 2,171,879 |  | 2,027,745
Consumer mortgage | FICO AB | Nonperforming |  |  |  |  |
Term loans amortized cost basis by origination year |  |  |  |  |
Year One | 0 |  | 0 |  | 0
Year Two | 415 |  | 415 |  | 75
Year Three | 707 |  | 707 |  | 573
Year Four | 566 |  | 566 |  | 184
Year Five | 175 |  | 175 |  | 399
Prior | 5,207 |  | 5,207 |  | 4,347
Revolving Loans Amortized Cost Basis | 0 |  | 0 |  | 0
Revolving Loans Converted to Term | 198 |  | 198 |  | 449
Total Loans | 7,268 |  | 7,268 |  | 6,027
Consumer mortgage | FICO CDE |  |  |  |  |
Term loans amortized cost basis by origination year |  |  |  |  |
Year One | 93,988 |  | 93,988 |  | 160,508
Year Two | 155,228 |  | 155,228 |  | 179,236
Year Three | 170,587 |  | 170,587 |  | 113,890
Year Four | 106,694 |  | 106,694 |  | 80,963
Year Five | 75,415 |  | 75,415 |  | 56,988
Prior | 357,416 |  | 357,416 |  | 336,366
Revolving Loans Amortized Cost Basis | 28,997 |  | 28,997 |  | 28,035
Revolving Loans Converted to Term | 29,292 |  | 29,292 |  | 22,717
Total Loans | 1,017,617 |  | 1,017,617 |  | 978,703
Consumer mortgage | FICO CDE | Performing |  |  |  |  |
Term loans amortized cost basis by origination year |  |  |  |  |
Year One | 93,988 |  | 93,988 |  | 160,388
Year Two | 153,636 |  | 153,636 |  | 178,262
Year Three | 169,225 |  | 169,225 |  | 112,640
Year Four | 105,444 |  | 105,444 |  | 79,357
Year Five | 73,939 |  | 73,939 |  | 54,861
Prior | 343,507 |  | 343,507 |  | 323,189
Revolving Loans Amortized Cost Basis | 28,997 |  | 28,997 |  | 27,884
Revolving Loans Converted to Term | 28,036 |  | 28,036 |  | 22,056
Total Loans | 996,772 |  | 996,772 |  | 958,637
Consumer mortgage | FICO CDE | Nonperforming |  |  |  |  |
Term loans amortized cost basis by origination year |  |  |  |  |
Year One | 0 |  | 0 |  | 120
Year Two | 1,592 |  | 1,592 |  | 974
Year Three | 1,362 |  | 1,362 |  | 1,250
Year Four | 1,250 |  | 1,250 |  | 1,606
Year Five | 1,476 |  | 1,476 |  | 2,127
Prior | 13,909 |  | 13,909 |  | 13,177
Revolving Loans Amortized Cost Basis | 0 |  | 0 |  | 151
Revolving Loans Converted to Term | 1,256 |  | 1,256 |  | 661
Total Loans | 20,845 |  | 20,845 |  | 20,066
Consumer indirect |  |  |  |  |
Term loans amortized cost basis by origination year |  |  |  |  |
Year One | 573,878 |  | 573,878 |  | 777,531
Year Two | 622,173 |  | 622,173 |  | 422,595
Year Three | 306,248 |  | 306,248 |  | 129,502
Year Four | 83,332 |  | 83,332 |  | 99,660
Year Five | 55,765 |  | 55,765 |  | 52,313
Prior | 66,906 |  | 66,906 |  | 58,052
Revolving Loans Amortized Cost Basis | 0 |  | 0 |  | 0
Revolving Loans Converted to Term | 0 |  | 0 |  | 0
Total Loans | 1,708,302 |  | 1,708,302 |  | 1,539,653
Year One |  |  | 277 |  |
Year Two |  |  | 2,551 |  |
Year Three |  |  | 1,435 |  |
Year Four |  |  | 890 |  |
Year Five |  |  | 482 |  |
Prior |  |  | 855 |  |
Revolving Loans Amortized Cost Basis |  |  | 0 |  |
Revolving Loans Converted to Term |  |  | 0 |  |
Total Loans |  |  | 6,490 |  |
Consumer indirect | Performing |  |  |  |  |
Term loans amortized cost basis by origination year |  |  |  |  |
Year One | 573,832 |  | 573,832 |  | 777,513
Year Two | 622,019 |  | 622,019 |  | 422,594
Year Three | 306,229 |  | 306,229 |  | 129,449
Year Four | 83,299 |  | 83,299 |  | 99,593
Year Five | 55,759 |  | 55,759 |  | 52,298
Prior | 66,874 |  | 66,874 |  | 58,028
Revolving Loans Amortized Cost Basis | 0 |  | 0 |  | 0
Revolving Loans Converted to Term | 0 |  | 0 |  | 0
Total Loans | 1,708,012 |  | 1,708,012 |  | 1,539,475
Consumer indirect | Nonperforming |  |  |  |  |
Term loans amortized cost basis by origination year |  |  |  |  |
Year One | 46 |  | 46 |  | 18
Year Two | 154 |  | 154 |  | 1
Year Three | 19 |  | 19 |  | 53
Year Four | 33 |  | 33 |  | 67
Year Five | 6 |  | 6 |  | 15
Prior | 32 |  | 32 |  | 24
Revolving Loans Amortized Cost Basis | 0 |  | 0 |  | 0
Revolving Loans Converted to Term | 0 |  | 0 |  | 0
Total Loans | 290 |  | 290 |  | 178
Consumer direct |  |  |  |  |
Term loans amortized cost basis by origination year |  |  |  |  |
Year One | 66,421 |  | 66,421 |  | 84,117
Year Two | 59,136 |  | 59,136 |  | 46,432
Year Three | 30,516 |  | 30,516 |  | 17,067
Year Four | 10,064 |  | 10,064 |  | 12,730
Year Five | 6,093 |  | 6,093 |  | 5,602
Prior | 6,367 |  | 6,367 |  | 5,070
Revolving Loans Amortized Cost Basis | 6,703 |  | 6,703 |  | 6,585
Revolving Loans Converted to Term | 1 |  | 1 |  | 2
Total Loans | 185,301 |  | 185,301 |  | 177,605
Year One |  |  | 70 |  |
Year Two |  |  | 524 |  |
Year Three |  |  | 378 |  |
Year Four |  |  | 48 |  |
Year Five |  |  | 73 |  |
Prior |  |  | 154 |  |
Revolving Loans Amortized Cost Basis |  |  | 119 |  |
Revolving Loans Converted to Term |  |  | 0 |  |
Total Loans |  |  | 1,366 |  |
Consumer direct | Performing |  |  |  |  |
Term loans amortized cost basis by origination year |  |  |  |  |
Year One | 66,421 |  | 66,421 |  | 84,111
Year Two | 59,136 |  | 59,136 |  | 46,381
Year Three | 30,516 |  | 30,516 |  | 17,066
Year Four | 10,059 |  | 10,059 |  | 12,729
Year Five | 6,088 |  | 6,088 |  | 5,573
Prior | 6,337 |  | 6,337 |  | 5,020
Revolving Loans Amortized Cost Basis | 6,690 |  | 6,690 |  | 6,563
Revolving Loans Converted to Term | 1 |  | 1 |  | 2
Total Loans | 185,248 |  | 185,248 |  | 177,445
Consumer direct | Nonperforming |  |  |  |  |
Term loans amortized cost basis by origination year |  |  |  |  |
Year One | 0 |  | 0 |  | 6
Year Two | 0 |  | 0 |  | 51
Year Three | 0 |  | 0 |  | 1
Year Four | 5 |  | 5 |  | 1
Year Five | 5 |  | 5 |  | 29
Prior | 30 |  | 30 |  | 50
Revolving Loans Amortized Cost Basis | 13 |  | 13 |  | 22
Revolving Loans Converted to Term | 0 |  | 0 |  | 0
Total Loans | 53 |  | 53 |  | 160
Home equity |  |  |  |  |
Term loans amortized cost basis by origination year |  |  |  |  |
Year One | 49,059 |  | 49,059 |  | 69,575
Year Two | 65,075 |  | 65,075 |  | 72,280
Year Three | 65,272 |  | 65,272 |  | 38,078
Year Four | 33,041 |  | 33,041 |  | 31,675
Year Five | 27,082 |  | 27,082 |  | 16,173
Prior | 48,095 |  | 48,095 |  | 41,703
Revolving Loans Amortized Cost Basis | 127,900 |  | 127,900 |  | 133,266
Revolving Loans Converted to Term | 29,240 |  | 29,240 |  | 31,246
Total Loans | 444,764 |  | 444,764 |  | 433,996
Year One |  |  | 0 |  |
Year Two |  |  | 0 |  |
Year Three |  |  | 0 |  |
Year Four |  |  | 64 |  |
Year Five |  |  | 0 |  |
Prior |  |  | 9 |  |
Revolving Loans Amortized Cost Basis |  |  | 17 |  |
Revolving Loans Converted to Term |  |  | 0 |  |
Total Loans |  |  | 90 |  |
Home equity | Performing |  |  |  |  |
Term loans amortized cost basis by origination year |  |  |  |  |
Year One | 49,059 |  | 49,059 |  | 69,575
Year Two | 64,935 |  | 64,935 |  | 72,270
Year Three | 65,262 |  | 65,262 |  | 37,964
Year Four | 32,797 |  | 32,797 |  | 31,506
Year Five | 26,802 |  | 26,802 |  | 16,068
Prior | 47,484 |  | 47,484 |  | 41,097
Revolving Loans Amortized Cost Basis | 126,958 |  | 126,958 |  | 132,703
Revolving Loans Converted to Term | 28,708 |  | 28,708 |  | 30,569
Total Loans | 442,005 |  | 442,005 |  | 431,752
Home equity | Nonperforming |  |  |  |  |
Term loans amortized cost basis by origination year |  |  |  |  |
Year One | 0 |  | 0 |  | 0
Year Two | 140 |  | 140 |  | 10
Year Three | 10 |  | 10 |  | 114
Year Four | 244 |  | 244 |  | 169
Year Five | 280 |  | 280 |  | 105
Prior | 611 |  | 611 |  | 606
Revolving Loans Amortized Cost Basis | 942 |  | 942 |  | 563
Revolving Loans Converted to Term | 532 |  | 532 |  | 677
Total Loans | $ 2,759 |  | $ 2,759 |  | $ 2,244

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