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COMMITMENTS, CONTINGENT LIABILITIES AND RESTRICTIONS (Details) - USD ($) $ in Thousands |  | 12 Months Ended
--- | --- | ---
Nov. 16, 2023 | Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
Commitments and contingencies |  |  |  |
Contract amount of commitments and contingencies |  | $ 1,555,901 | $ 1,544,138 |
Federal Reserve unused borrowing capacity |  | 1,110,000 |  |
Loss contingency accrual, payments |  | 5,800 |  |
Basis points | 0.134% |  |  |
Uninsured deposits |  |  | 5,000,000 |
FDIC expenses |  | 1,500 |  |
Litigation accrual |  | 5,800 | 0 | $ (100)
FDIC insurance expense |  | 9,500 | 5,500 | $ 4,100
Commitments to extend credit |  |  |  |
Commitments and contingencies |  |  |  |
Contract amount of commitments and contingencies |  | 1,494,549 | 1,486,791 |
Standby letters of credit |  |  |  |
Commitments and contingencies |  |  |  |
Contract amount of commitments and contingencies |  | $ 61,352 | $ 57,347 |

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