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INCOME TAXES - Effective Tax Rate Reconciliation (Details) | 12 Months Ended
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Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
Effective tax rate reconciliation |  |  |
Federal statutory income tax rate | 21.00% | 21.00% | 21.00%
Increase (reduction) in taxes resulting from: |  |  |
Tax-exempt interest | (1.70%) | (1.30%) | (1.10%)
State income taxes, net of federal benefit | 2.20% | 3.30% | 3.60%
Stock-based compensation | (0.20%) | (0.30%) | (0.90%)
Federal tax credits | (0.50%) | (1.00%) | (1.00%)
Other, net | 0.80% | 0.00% | (0.20%)
Effective income tax rate | 21.60% | 21.70% | 21.40%

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