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STOCK-BASED COMPENSATION PLANS - Performance Awards - Additional information (Details) $ in Thousands | 12 Months Ended
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Dec. 31, 2023 USD ($) item shares | Dec. 31, 2022 USD ($) shares | Dec. 31, 2021 USD ($) shares
STOCK-BASED COMPENSATION PLANS |  |  |
Shares issuable | 81,138 | 31,999 | 47,820
Performance Awards |  |  |
STOCK-BASED COMPENSATION PLANS |  |  |
Number of sets of performance criteria | item | 2 |  |
Cumulative period of Relative Total Shareholder Pattern | 3 years |  |
Relative TSR employment weightage (as percent) | 50.00% |  |
Core ROATCE period | 3 years |  |
Relative Total Performance Goal, weightage (as percent) | 50.00% |  |
Vesting period | 3 years |  |
Estimated payout percent | 96.00% |  |
Shares issuable | 81,138 |  |
Shares issued in connection with stock option exercise (in shares) | 52,588 | 28,550 |
Unrecognized stock-based compensation expense | $ | $ 1,900 |  |
Weighted average period for recognition of unrecognized compensation cost | 1 year 9 months 18 days |  |
Total fair value of restricted stock vested | $ |  | $ 20 | $ 10

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