INCOME TAXES - Effective Tax Rate Reconciliation (Details)	12 Months Ended
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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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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Percentage of difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying domestic federal statutory income tax rate to pretax income (loss) from continuing operation, attributable to nondeductible expense for share-based payment arrangement.

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