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LOANS AND ALLOWANCE FOR CREDIT LOSSES - Allowance for Credit Losses (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020
Allowance for credit losses - loans. |  |  |
Beginning balance | $ 49,869 |  |
Provision | 14,773 | $ (8,839) | $ 14,212
Ending balance | 61,059 | 49,869 |
Liabilities for off-balance-sheet credit exposures |  |  |
Charge-offs | 0 | 0 |
Recoveries | 0 | 0 |
PCD Allowance at Acquisition | 0 |  |
Provision | 320 |  |
Beginning balance | 803 | 1,489 | 0
Ending balance | 1,123 | 803 | 1,489
Allowance for Credit Losses |  |  |
Accrued interest and fees receivable | 25,100 | 16,700 |
Allowance for loan losses | 61,059 | 49,869 |
Elmira acquisition |  |  |
Allowance for credit losses - loans. |  |  |
Beginning balance | 49,900 |  |
Ending balance | 61,100 | 49,900 |
Allowance for Credit Losses |  |  |
Allowance for loan losses | 61,100 | 49,900 |
Topic ASC 326 |  |  |
Liabilities for off-balance-sheet credit exposures |  |  |
Charge-offs |  |  | 0
Recoveries |  |  | 0
Steuben acquisition |  |  | 67
Provision |  | (686) | 237
Beginning balance |  | 1,489 | 1,185
Ending balance |  |  | 1,489
Topic ASC 326 | Cumulative Effect Adjustment |  |  |
Liabilities for off-balance-sheet credit exposures |  |  |
Beginning balance |  |  | 1,185
Acquired Impaired Loans |  |  |
Allowance for credit losses - loans. |  |  |
Beginning balance |  |  | 163
Allowance for Credit Losses |  |  |
Allowance for loan losses |  |  |
Acquired Impaired Loans | Topic ASC 326 |  |  |
Allowance for credit losses - loans. |  |  |
Beginning balance |  | 0 | (163)
Charge-offs |  |  | 0
Recoveries |  |  | 0
Steuben acquisition |  |  | 0
Provision |  |  | 0
Ending balance |  |  | 0
Allowance for Credit Losses |  |  |
Allowance for loan losses |  |  | 0
Acquired Impaired Loans | Topic ASC 326 | Cumulative Effect Adjustment |  |  |
Allowance for credit losses - loans. |  |  |
Beginning balance |  |  | 0
Allowance for Credit Losses |  |  |
Allowance for loan losses |  |  |
Home Equity |  |  |
Allowance for credit losses - loans. |  |  |
Beginning balance |  |  | 2,129
Allowance for Credit Losses |  |  |
Allowance for loan losses |  |  |
Home Equity | Topic ASC 326 |  |  |
Allowance for credit losses - loans. |  |  |
Beginning balance |  | 2,222 | 808
Charge-offs |  |  | (199)
Recoveries |  |  | 28
Steuben acquisition |  |  | 235
Provision |  |  | (779)
Ending balance |  |  | 2,222
Allowance for Credit Losses |  |  |
Allowance for loan losses |  |  | 2,222
Home Equity | Topic ASC 326 | Cumulative Effect Adjustment |  |  |
Allowance for credit losses - loans. |  |  |
Beginning balance |  |  | 2,937
Allowance for Credit Losses |  |  |
Allowance for loan losses |  |  |
Commercial Portfolio Segment | Business Lending |  |  |
Allowance for credit losses - loans. |  |  |
Beginning balance | 22,995 | 30,072 | 19,426
Charge-offs |  | (1,922) |
Recoveries |  | 796 |
Ending balance |  | 22,995 | 30,072
Allowance for Credit Losses |  |  |
Allowance for loan losses |  | 22,995 | 30,072
Commercial Portfolio Segment | Business Lending | Topic ASC 326 |  |  |
Allowance for credit losses - loans. |  |  |
Beginning balance |  | 30,072 | 3,360
Charge-offs |  |  | (1,588)
Recoveries |  |  | 796
Steuben acquisition |  |  | 3,011
Provision |  | (5,951) | 5,067
Ending balance |  |  | 30,072
Allowance for Credit Losses |  |  |
Allowance for loan losses |  |  | 30,072
Commercial Portfolio Segment | Business Lending | Topic ASC 326 | Cumulative Effect Adjustment |  |  |
Allowance for credit losses - loans. |  |  |
Beginning balance |  |  | 22,786
Allowance for Credit Losses |  |  |
Allowance for loan losses |  |  |
Commercial Portfolio Segment | Consumer Mortgage |  |  |
Allowance for credit losses - loans. |  |  |
Beginning balance | 10,017 | 10,672 | 10,269
Charge-offs |  | (426) |
Recoveries |  | 91 |
Ending balance |  | 10,017 | 10,672
Allowance for Credit Losses |  |  |
Allowance for loan losses |  | 10,017 | 10,672
Commercial Portfolio Segment | Consumer Mortgage | Topic ASC 326 |  |  |
Allowance for credit losses - loans. |  |  |
Beginning balance |  | 10,672 | (1,051)
Charge-offs |  |  | (862)
Recoveries |  |  | 130
Steuben acquisition |  |  | 146
Provision |  | (320) | 2,040
Ending balance |  |  | 10,672
Allowance for Credit Losses |  |  |
Allowance for loan losses |  |  | 10,672
Commercial Portfolio Segment | Consumer Mortgage | Topic ASC 326 | Cumulative Effect Adjustment |  |  |
Allowance for credit losses - loans. |  |  |
Beginning balance |  |  | 9,218
Allowance for Credit Losses |  |  |
Allowance for loan losses |  |  |
Consumer Portfolio Segment | Business Lending |  |  |
Allowance for credit losses - loans. |  |  |
Beginning balance | 22,995 |  |
Charge-offs | (824) |  |
Recoveries | 1,374 |  |
PCD Allowance at Acquisition | 71 |  |
Provision | (319) |  |
Ending balance | 23,297 | 22,995 |
Allowance for Credit Losses |  |  |
Allowance for loan losses | 23,297 | 22,995 |
Consumer Portfolio Segment | Consumer Mortgage |  |  |
Allowance for credit losses - loans. |  |  |
Beginning balance | 10,017 |  |
Charge-offs | (313) |  |
Recoveries | 62 |  |
PCD Allowance at Acquisition | 0 |  |
Provision | 4,577 |  |
Ending balance | 14,343 | 10,017 |
Allowance for Credit Losses |  |  |
Allowance for loan losses | 14,343 | 10,017 |
Consumer Portfolio Segment | Consumer Indirect |  |  |
Allowance for credit losses - loans. |  |  |
Beginning balance | 11,737 | 13,696 | 13,712
Charge-offs | (7,986) | (5,160) |
Recoveries | 4,756 | 4,346 |
PCD Allowance at Acquisition | 0 |  |
Provision | 9,345 |  |
Ending balance | 17,852 | 11,737 | 13,696
Allowance for Credit Losses |  |  |
Allowance for loan losses | 17,852 | 11,737 | 13,696
Consumer Portfolio Segment | Consumer Indirect | Topic ASC 326 |  |  |
Allowance for credit losses - loans. |  |  |
Beginning balance |  | 13,696 | (997)
Charge-offs |  |  | (6,382)
Recoveries |  |  | 3,992
Steuben acquisition |  |  | 183
Provision |  | (1,145) | 3,188
Ending balance |  |  | 13,696
Allowance for Credit Losses |  |  |
Allowance for loan losses |  |  | 13,696
Consumer Portfolio Segment | Consumer Indirect | Topic ASC 326 | Cumulative Effect Adjustment |  |  |
Allowance for credit losses - loans. |  |  |
Beginning balance |  |  | 12,715
Allowance for Credit Losses |  |  |
Allowance for loan losses |  |  |
Consumer Portfolio Segment | Consumer Direct |  |  |
Allowance for credit losses - loans. |  |  |
Beginning balance | 2,306 | 3,207 | 3,255
Charge-offs | (1,252) | (1,232) |
Recoveries | 772 | 793 |
PCD Allowance at Acquisition | 0 |  |
Provision | 1,147 |  |
Ending balance | 2,973 | 2,306 | 3,207
Allowance for Credit Losses |  |  |
Allowance for loan losses | 2,973 | 2,306 | 3,207
Consumer Portfolio Segment | Consumer Direct | Topic ASC 326 |  |  |
Allowance for credit losses - loans. |  |  |
Beginning balance |  | 3,207 | (643)
Charge-offs |  |  | (1,633)
Recoveries |  |  | 743
Steuben acquisition |  |  | 87
Provision |  | (462) | 1,398
Ending balance |  |  | 3,207
Allowance for Credit Losses |  |  |
Allowance for loan losses |  |  | 3,207
Consumer Portfolio Segment | Consumer Direct | Topic ASC 326 | Cumulative Effect Adjustment |  |  |
Allowance for credit losses - loans. |  |  |
Beginning balance |  |  | 2,612
Allowance for Credit Losses |  |  |
Allowance for loan losses |  |  |
Consumer Portfolio Segment | Home Equity |  |  |
Allowance for credit losses - loans. |  |  |
Beginning balance | 1,814 | 2,222 |
Charge-offs | (86) | (225) |
Recoveries | 163 | 92 |
PCD Allowance at Acquisition | 0 |  |
Provision | (297) |  |
Ending balance | 1,594 | 1,814 | 2,222
Allowance for Credit Losses |  |  |
Allowance for loan losses | 1,594 | 1,814 | 2,222
Consumer Portfolio Segment | Home Equity | Topic ASC 326 |  |  |
Allowance for credit losses - loans. |  |  |
Provision |  | (275) |
Unallocated Financing Receivables |  |  |
Allowance for credit losses - loans. |  |  |
Beginning balance | 1,000 | 1,000 | 957
Charge-offs | 0 | 0 |
Recoveries | 0 | 0 |
PCD Allowance at Acquisition | 0 |  |
Provision | 0 |  |
Ending balance | 1,000 | 1,000 | 1,000
Allowance for Credit Losses |  |  |
Allowance for loan losses | 1,000 | 1,000 | 1,000
Unallocated Financing Receivables | Topic ASC 326 |  |  |
Allowance for credit losses - loans. |  |  |
Beginning balance |  | 1,000 | 43
Charge-offs |  |  | 0
Recoveries |  |  | 0
Steuben acquisition |  |  | 0
Provision |  | 0 | 0
Ending balance |  |  | 1,000
Allowance for Credit Losses |  |  |
Allowance for loan losses |  |  | 1,000
Unallocated Financing Receivables | Topic ASC 326 | Cumulative Effect Adjustment |  |  |
Allowance for credit losses - loans. |  |  |
Beginning balance |  |  | 1,000
Allowance for Credit Losses |  |  |
Allowance for loan losses |  |  |
Allowances for credit losses |  |  |
Allowance for credit losses - loans. |  |  |
Beginning balance | 49,869 | 60,869 | 49,911
Charge-offs | (10,461) | (8,965) |
Recoveries | 7,127 | 6,118 |
PCD Allowance at Acquisition | 71 |  |
Provision | 14,453 |  |
Ending balance | 61,059 | 49,869 | 60,869
Allowance for Credit Losses |  |  |
Allowance for loan losses | 61,059 | 49,869 | 60,869
Allowances for credit losses | Topic ASC 326 |  |  |
Allowance for credit losses - loans. |  |  |
Beginning balance |  | 60,869 | 1,357
Charge-offs |  |  | (10,664)
Recoveries |  |  | 5,689
Steuben acquisition |  |  | 3,662
Provision |  | (8,153) | 10,914
Ending balance |  |  | 60,869
Allowance for Credit Losses |  |  |
Allowance for loan losses |  |  | 60,869
Allowances for credit losses | Topic ASC 326 | Cumulative Effect Adjustment |  |  |
Allowance for credit losses - loans. |  |  |
Beginning balance |  |  | 51,268
Allowance for Credit Losses |  |  |
Allowance for loan losses |  |  |
Total allowances for credit losses |  |  |
Allowance for credit losses - loans. |  |  |
Beginning balance | 50,672 | 62,358 | 49,911
Charge-offs | (10,461) | (8,965) |
Recoveries | 7,127 | 6,118 |
PCD Allowance at Acquisition | 71 |  |
Provision | 14,773 |  |
Ending balance | 62,182 | 50,672 | 62,358
Allowance for Credit Losses |  |  |
Allowance for loan losses | $ 62,182 | 50,672 | 62,358
Total allowances for credit losses | Topic ASC 326 |  |  |
Allowance for credit losses - loans. |  |  |
Beginning balance |  | 62,358 | 2,542
Charge-offs |  |  | (10,664)
Recoveries |  |  | 5,689
Steuben acquisition |  |  | 3,729
Provision |  | $ (8,839) | 11,151
Ending balance |  |  | 62,358
Allowance for Credit Losses |  |  |
Allowance for loan losses |  |  | 62,358
Total allowances for credit losses | Topic ASC 326 | Cumulative Effect Adjustment |  |  |
Allowance for credit losses - loans. |  |  |
Beginning balance |  |  | $ 52,453
Allowance for Credit Losses |  |  |
Allowance for loan losses |  |  |

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