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LOANS AND ALLOWANCE FOR CREDIT LOSSES - Past Due Status of Modifications under ASU 2022-02 (Details) - USD ($) $ in Thousands | Jun. 30, 2024 | Dec. 31, 2023 | Jun. 30, 2023
--- | --- | --- | ---
Financing Receivable, Past Due [Line Items] |  |  |
Loans, net of deferred loan fees | $ 2,011,472 | $ 1,972,664 |
Total Past Due |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans, net of deferred loan fees | 12,465 | 14,360 |
30 - 59 Days Past Due |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans, net of deferred loan fees | 6,771 | 9,562 |
60 - 89 Days Past Due |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans, net of deferred loan fees | 1,060 | 943 |
90 Days or More Past Due |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans, net of deferred loan fees | 4,634 | 3,855 |
Loans Not Past Due |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans, net of deferred loan fees | 1,999,007 | 1,958,304 |
Commercial and industrial |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans, net of deferred loan fees | 290,546 | 264,396 |
Commercial and industrial | Total Past Due |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans, net of deferred loan fees | 1,295 | 1,237 |
Commercial and industrial | 30 - 59 Days Past Due |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans, net of deferred loan fees | 138 | 1,196 |
Commercial and industrial | 60 - 89 Days Past Due |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans, net of deferred loan fees | 271 | 31 |
Commercial and industrial | 90 Days or More Past Due |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans, net of deferred loan fees | 886 | 10 |
Commercial and industrial | Loans Not Past Due |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans, net of deferred loan fees | 289,251 | 263,159 |
Residential Mortgages |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans, net of deferred loan fees | 271,620 | 277,992 |
Residential Mortgages | Total Past Due |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans, net of deferred loan fees | 4,522 | 3,030 |
Residential Mortgages | 30 - 59 Days Past Due |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans, net of deferred loan fees | 3,203 | 2,244 |
Residential Mortgages | 60 - 89 Days Past Due |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans, net of deferred loan fees | 422 | 201 |
Residential Mortgages | 90 Days or More Past Due |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans, net of deferred loan fees | 897 | 585 |
Residential Mortgages | Loans Not Past Due |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans, net of deferred loan fees | 267,098 | 274,962 |
Consumer Loans |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans, net of deferred loan fees | 294,594 | 307,351 |
Consumer Loans | Home equity lines and loans |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans, net of deferred loan fees | 87,228 | 87,056 |
Consumer Loans | Total Past Due | Home equity lines and loans |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans, net of deferred loan fees | 574 | 914 |
Consumer Loans | 30 - 59 Days Past Due | Home equity lines and loans |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans, net of deferred loan fees | 298 | 461 |
Consumer Loans | 60 - 89 Days Past Due | Home equity lines and loans |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans, net of deferred loan fees | 66 | 87 |
Consumer Loans | 90 Days or More Past Due | Home equity lines and loans |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans, net of deferred loan fees | 210 | 366 |
Consumer Loans | Loans Not Past Due | Home equity lines and loans |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans, net of deferred loan fees | 86,654 | 86,142 |
Commercial Mortgages |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans, net of deferred loan fees | 1,154,712 | 1,122,925 |
Commercial Mortgages | Commercial mortgages, other |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans, net of deferred loan fees | 1,008,343 | 984,038 |
Commercial Mortgages | Total Past Due | Commercial mortgages, other |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans, net of deferred loan fees | 1,306 | 1,386 |
Commercial Mortgages | 30 - 59 Days Past Due | Commercial mortgages, other |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans, net of deferred loan fees | 1,062 | 1,022 |
Commercial Mortgages | 60 - 89 Days Past Due | Commercial mortgages, other |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans, net of deferred loan fees | 94 | 103 |
Commercial Mortgages | 90 Days or More Past Due | Commercial mortgages, other |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans, net of deferred loan fees | 150 | 261 |
Commercial Mortgages | Loans Not Past Due | Commercial mortgages, other |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans, net of deferred loan fees | 1,007,037 | $ 982,652 |
Restructured Debt | Total Past Due |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans, net of deferred loan fees | 1,352 |  |
Restructured Debt | 30 - 59 Days Past Due |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans, net of deferred loan fees | 0 |  |
Restructured Debt | 60 - 89 Days Past Due |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans, net of deferred loan fees | 0 |  |
Restructured Debt | 90 Days or More Past Due |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans, net of deferred loan fees | 1,115 |  |
Restructured Debt | Loans Not Past Due |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans, net of deferred loan fees | 237 |  |
Restructured Debt | Commercial and industrial | Total Past Due |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans, net of deferred loan fees | 796 |  |
Restructured Debt | Commercial and industrial | 30 - 59 Days Past Due |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans, net of deferred loan fees | 0 |  |
Restructured Debt | Commercial and industrial | 60 - 89 Days Past Due |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans, net of deferred loan fees | 0 |  |
Restructured Debt | Commercial and industrial | 90 Days or More Past Due |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans, net of deferred loan fees | 675 |  |
Restructured Debt | Commercial and industrial | Loans Not Past Due |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans, net of deferred loan fees | 121 |  |
Restructured Debt | Residential Mortgages | Total Past Due |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans, net of deferred loan fees | 440 |  |
Restructured Debt | Residential Mortgages | 30 - 59 Days Past Due |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans, net of deferred loan fees | 0 |  |
Restructured Debt | Residential Mortgages | 60 - 89 Days Past Due |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans, net of deferred loan fees | 0 |  |
Restructured Debt | Residential Mortgages | 90 Days or More Past Due |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans, net of deferred loan fees | 440 |  |
Restructured Debt | Residential Mortgages | Loans Not Past Due |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans, net of deferred loan fees | 0 |  |
Restructured Debt | Consumer Loans | Total Past Due | Home equity lines and loans |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans, net of deferred loan fees | 116 |  |
Restructured Debt | Consumer Loans | 30 - 59 Days Past Due | Home equity lines and loans |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans, net of deferred loan fees | 0 |  |
Restructured Debt | Consumer Loans | 60 - 89 Days Past Due | Home equity lines and loans |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans, net of deferred loan fees | 0 |  |
Restructured Debt | Consumer Loans | 90 Days or More Past Due | Home equity lines and loans |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans, net of deferred loan fees | 0 |  |
Restructured Debt | Consumer Loans | Loans Not Past Due | Home equity lines and loans |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans, net of deferred loan fees | $ 116 |  |
Restructured Debt | Commercial Mortgages | Total Past Due | Commercial mortgages, other |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans, net of deferred loan fees |  |  | $ 271
Restructured Debt | Commercial Mortgages | 30 - 59 Days Past Due | Commercial mortgages, other |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans, net of deferred loan fees |  |  | 0
Restructured Debt | Commercial Mortgages | 60 - 89 Days Past Due | Commercial mortgages, other |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans, net of deferred loan fees |  |  | 0
Restructured Debt | Commercial Mortgages | 90 Days or More Past Due | Commercial mortgages, other |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans, net of deferred loan fees |  |  | 0
Restructured Debt | Commercial Mortgages | Loans Not Past Due | Commercial mortgages, other |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans, net of deferred loan fees |  |  | $ 271

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