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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Recent Accounting Pronouncements (Details) - USD ($) $ in Thousands | Jan. 01, 2023 | Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020
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New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |  |
Adjustments due to new accounting pronouncements |  | $ 166,388 | $ 211,455 | $ 199,699
Allowance for loan losses |  | 19,659 | 21,025 | 20,924
Retained Earnings |  |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |  |
Adjustments due to new accounting pronouncements |  | 211,859 | $ 188,877 | $ 168,006
Forecast | Securities Portfolio |  |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |  |
Allowance for loan losses | $ 0 |  |  |
Forecast | Unfunded Commitments |  |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |  |
Allowance for loan losses, net of tax | 900 |  |  |
Allowance for loan losses | $ 1,200 |  |  |
Cumulative Effect, Period of Adoption, Adjustment | Maximum | Pro Forma | Retained Earnings |  |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |  |
Adjustments due to new accounting pronouncements |  | 2,000 |  |
Allowance for loan losses, net of tax |  | $ 1,400 |  |

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