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ACQUISITIONS - Summary of Loans Acquired (Details) - USD ($) $ in Thousands | Dec. 31, 2022 | Dec. 31, 2021
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Elmira transaction | Non-PCD Loans |  |
Certain Loans Acquired During The Period |  |
Unpaid principal balance of non-PCD loans | $ 455,700 |
Net discount on fair value adjustments of non-PCD loans | 20,800 |
Steuben Trust Corporation | Acquired Impaired |  |
Certain Loans Acquired During The Period |  |
Par value of PCD loans at acquisition | 2,184 |
Allowance for credit losses at acquisition | (71) |
Non-credit (discount)/premium at acquisition | 81 |
Fair value of PCD loans at acquisition | 2,032 |
Steuben Trust Corporation | Non-PCD Loans |  |
Certain Loans Acquired During The Period |  |
Par value of PCD loans at acquisition |  | $ 35,906
Allowance for credit losses at acquisition |  | (668)
Non-credit (discount)/premium at acquisition |  | (103)
Fair value of PCD loans at acquisition |  | $ 35,341
Unpaid principal balance of non-PCD loans | 313,000 |
Net premium on fair value adjustments of non-PCD loans | $ 2,500 |

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