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EMPLOYEE BENEFITS - Narrative (Details) | 3 Months Ended | 12 Months Ended
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Jun. 30, 2021 | Mar. 31, 2021 | Dec. 31, 2023 USD ($) executive_officer retiree shares | Dec. 31, 2022 USD ($) retiree shares | Dec. 31, 2021 USD ($) retiree shares | Dec. 31, 2018 executive_officer | Dec. 31, 2013 executive_officer
Health Insurance Coverage [Abstract] |  |  |  |  |  |  |
Cost of health care benefits |  |  | $ 8,100,000 | $ 8,400,000 | $ 8,600,000 |  |
Health coverage eligibility for retiring employees, minimum years of service |  |  | 50 years |  |  |  |
Retirees participating in health insurance | retiree |  |  | 1 | 1 | 1 |  |
Employee Stock Ownership Plan (ESOP) [Abstract] |  |  |  |  |  |  |
Contributions to the employee stock ownership plan (ESOP) |  |  | $ 1,000,000 | $ 1,000,000 | $ 1,000,000 |  |
Shares owned by the ESOP (in shares) | shares |  |  | 366,791 | 345,847 |  |  |
Supplemental Unemployment Benefits [Abstract] |  |  |  |  |  |  |
Long-term disability coverage, minimum years of service rendered for officers to automatically qualify |  |  | 3 years |  |  |  |
Long-term disability coverage, minimum annual salary level for officers to automatically qualify |  |  | $ 50,000 |  |  |  |
Long-term disability coverage, maximum benefit provided, per month |  |  | $ 15,000 |  |  |  |
401(k) [Abstract] |  |  |  |  |  |  |
Requisite service period |  |  | 30 days |  |  |  |
401(k) Plan expense |  |  | $ 2,200,000 | $ 2,000,000 | $ 2,200,000 |  |
Defined Benefit Plan [Abstract] |  |  |  |  |  |  |
Adjustment To Pension Liability |  |  | $ 948,000 | $ 5,400,000 |  |  |
Retirement Plan |  |  |  |  |  |  |
Defined Benefit Plan [Abstract] |  |  |  |  |  |  |
Defined benefit pension plan, minimum eligibility age |  |  | 65 years |  |  |  |
Early retirement election at reduced benefit levels, minimum eligibility age |  |  | 55 years |  |  |  |
Discount rate |  |  | 5.13% | 5.46% |  |  |
Number of shares of Company stock included in plan assets (in shares) | shares |  |  | 240,666 | 240,666 |  |  |
Expected long-term rate of return on plan assets | 6.125% | 6.50% | 6.13% | 6.13% | 6.13% |  |
Funded (under funded) status |  |  | $ 8,386,000 | $ 6,866,000 | $ 3,269,000 |  |
Accrued benefit (liability) asset recognized |  |  | 8,386,000 | $ 6,866,000 | $ 3,269,000 |  |
Expected future employer contributions, next fiscal year |  |  | $ 0 |  |  |  |
Retirement Plan Acquired |  |  |  |  |  |  |
Defined Benefit Plan [Abstract] |  |  |  |  |  |  |
Discount rate |  |  | 5.13% | 5.46% |  |  |
Expected long-term rate of return on plan assets | 6.125% | 6.50% | 6.13% | 6.13% | 6.13% |  |
Funded (under funded) status |  |  | $ 839,000 | $ 749,000 | $ 388,000 |  |
Accrued benefit (liability) asset recognized |  |  | 839,000 | $ 749,000 | 388,000 |  |
Expected future employer contributions, next fiscal year |  |  | $ 0 |  |  |  |
Restoration Plan |  |  |  |  |  |  |
Defined Benefit Plan [Abstract] |  |  |  |  |  |  |
Discount rate |  |  | 5.13% | 5.46% |  |  |
Funded (under funded) status |  |  | $ (16,176,000) | $ (15,463,000) | (19,321,000) |  |
Accrued benefit (liability) asset recognized |  |  | (16,176,000) | $ (15,463,000) | $ (19,321,000) |  |
Expected future employer contributions, next fiscal year |  |  | $ 725,000 |  |  |  |
Equity securities | Retirement Plan |  |  |  |  |  |  |
Defined Benefit Plan [Abstract] |  |  |  |  |  |  |
Target allocation |  |  | 64.00% |  |  |  |
Fixed income securities | Retirement Plan |  |  |  |  |  |  |
Defined Benefit Plan [Abstract] |  |  |  |  |  |  |
Target allocation |  |  | 35.00% |  |  |  |
Cash equivalents | Retirement Plan |  |  |  |  |  |  |
Defined Benefit Plan [Abstract] |  |  |  |  |  |  |
Target allocation |  |  | 1.00% |  |  |  |
Stock options |  |  |  |  |  |  |
Share-based Payment Arrangement, Noncash Expense [Abstract] |  |  |  |  |  |  |
Granted (shares) | shares |  |  | 0 | 0 | 0 |  |
Restricted Stock Units (RSUs) |  |  |  |  |  |  |
Share-based Payment Arrangement, Noncash Expense [Abstract] |  |  |  |  |  |  |
Nonvested awards outstanding (in shares) | shares |  |  | 197,943 | 225,928 |  |  |
Performance Based Restricted Stock Units |  |  |  |  |  |  |
Share-based Payment Arrangement, Noncash Expense [Abstract] |  |  |  |  |  |  |
Nonvested awards outstanding (in shares) | shares |  |  | 28,654 | 13,514 |  |  |
Incentive Plan 2009 |  |  |  |  |  |  |
Share-based Payment Arrangement, Noncash Expense [Abstract] |  |  |  |  |  |  |
Number of additional shares (in shares) | shares |  |  | 410,000 |  |  |  |
Incentive Plan 2017 |  |  |  |  |  |  |
Share-based Payment Arrangement, Noncash Expense [Abstract] |  |  |  |  |  |  |
Common stock shares reserved and available for issuance (in shares) | shares |  |  | 2,460,000 |  |  |  |
Shares remaining available for grant for future awards (in shares) | shares |  |  | 1,033,423 |  |  |  |
Incentive Plan |  |  |  |  |  |  |
Share-based Payment Arrangement, Noncash Expense [Abstract] |  |  |  |  |  |  |
Nonvested awards outstanding (in shares) | shares |  |  | 201,315 | 277,600 | 368,447 |  |
Unrecognized compensation expense |  |  | $ 5,700,000 | $ 7,400,000 | $ 6,200,000 |  |
Unrecognized compensation, weighted-average period for recognition |  |  | 2 years 3 months 18 days |  |  |  |
Incentive Plan | Stock options |  |  |  |  |  |  |
Share-based Payment Arrangement, Noncash Expense [Abstract] |  |  |  |  |  |  |
Weighted-average remaining contractual life of options exercisable |  |  | 4 years 3 months 18 days |  |  |  |
Awards contractual term |  |  | 10 years |  |  |  |
Total intrinsic value of outstanding stock options |  |  | $ 453,000 |  |  |  |
Total intrinsic value of exercisable stock options |  |  | $ 453,000 |  |  |  |
Incentive Plan | Stock options | Minimum |  |  |  |  |  |  |
Share-based Payment Arrangement, Noncash Expense [Abstract] |  |  |  |  |  |  |
Awards vesting period |  |  | 3 years |  |  |  |
Incentive Plan | Stock options | Maximum |  |  |  |  |  |  |
Share-based Payment Arrangement, Noncash Expense [Abstract] |  |  |  |  |  |  |
Awards vesting period |  |  | 4 years |  |  |  |
Incentive Plan | Restricted Stock Units (RSUs) | Minimum |  |  |  |  |  |  |
Share-based Payment Arrangement, Noncash Expense [Abstract] |  |  |  |  |  |  |
Awards vesting period |  |  | 3 years |  |  |  |
Incentive Plan | Restricted Stock Units (RSUs) | Maximum |  |  |  |  |  |  |
Share-based Payment Arrangement, Noncash Expense [Abstract] |  |  |  |  |  |  |
Awards vesting period |  |  | 4 years |  |  |  |
Incentive Plan | Performance Based Restricted Stock Units |  |  |  |  |  |  |
Share-based Payment Arrangement, Noncash Expense [Abstract] |  |  |  |  |  |  |
Shares earned, performance period |  |  | 3 years |  |  |  |
Performance earnings, minimum payout (as a percentage) |  |  | 50.00% |  |  |  |
Performance earnings, target payout (as a percentage) |  |  | 100.00% |  |  |  |
Performance earnings, maximum payout (as a percentage) |  |  | 150.00% |  |  |  |
Executive officers |  |  |  |  |  |  |
Deferred Compensation Arrangements [Abstract] |  |  |  |  |  |  |
Number of employees included in the deferred compensation agreement with the Company | executive_officer |  |  | 33 |  |  |  |
Aggregate payment amount provided in the deferred compensation agreements |  |  | $ 10,100,000 |  |  |  |
Deferred Compensation Arrangement with Individual, Maximum Contractual Term |  |  | 15 years |  |  |  |
Number of individuals receiving payments | executive_officer |  |  | 11 |  |  |  |
Deferred compensation expense |  |  | $ 86,000 | 310,000 | 457,000 |  |
Total deferred compensation plan liability |  |  | $ 3,200,000 | 3,500,000 |  |  |
Split Dollar Life Insurance Agreements [Abstract] |  |  |  |  |  |  |
Number of employees originally covered by the split dollar agreements | executive_officer |  |  | 8 |  |  |  |
Aggregate death benefit amount provided originally in agreement, before inflation adjustment |  |  | $ 4,500,000 |  |  |  |
Number of employees covered by the split dollar agreements, Actively employed with us | executive_officer |  |  | 3 |  |  |  |
Number of retired covered officers death benefits were paid | executive_officer |  |  |  |  |  | 1 |
Number of active covered officers death benefits were paid | executive_officer |  |  |  |  |  |  | 1
Number of remaining employees covered by the split dollar agreements | executive_officer |  |  | 7 |  |  |  |
Aggregate death benefits for remaining executives, inflation adjusted |  |  | $ 5,800,000 |  |  |  |
Expense of Split Dollar Retirement Bonus |  |  | (95,000) | 27,000 | 87,000 |  |
Total split dollar liability |  |  | $ 1,600,000 | 1,900,000 |  |  |
Executive officers | Minimum |  |  |  |  |  |  |
Split Dollar Life Insurance Agreements [Abstract] |  |  |  |  |  |  |
Inflation adjustment factor applied to benefits, annual |  |  | 3.00% |  |  |  |
Executive officers | Maximum |  |  |  |  |  |  |
Split Dollar Life Insurance Agreements [Abstract] |  |  |  |  |  |  |
Inflation adjustment factor applied to benefits, annual |  |  | 5.00% |  |  |  |
Employee | Incentive Plan |  |  |  |  |  |  |
Share-based Payment Arrangement, Noncash Expense [Abstract] |  |  |  |  |  |  |
Share-based compensation expense |  |  | $ 3,200,000 | 2,900,000 | 2,700,000 |  |
Tax benefit from share-based compensation expense |  |  | 671,000 | 605,000 | 570,000 |  |
Director | Incentive Plan |  |  |  |  |  |  |
Share-based Payment Arrangement, Noncash Expense [Abstract] |  |  |  |  |  |  |
Share-based compensation expense |  |  | 359,000 | 342,000 | 306,000 |  |
Tax benefit from share-based compensation expense |  |  | $ 75,000 | $ 72,000 | $ 64,000 |  |
Director | Incentive Plan | Restricted Stock Units (RSUs) |  |  |  |  |  |  |
Share-based Payment Arrangement, Noncash Expense [Abstract] |  |  |  |  |  |  |
Awards vesting period |  |  | 1 year |  |  |  |

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