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EMPLOYEE BENEFITS AND STOCK BASED COMPENSATION (Narrative) (Details) |  | 12 Months Ended
--- | --- | ---
May 04, 2021 shares | Dec. 31, 2023 USD ($) item shares | Dec. 31, 2022 USD ($) shares | Dec. 31, 2021 USD ($) shares
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Plan expiration date | May 03, 2031 |  |  |
Number of shares available for future issuance | shares |  | 1,204,260 |  |
Maximum term of stock options |  | 10 years |  |
Vesting period of stock awards |  | 5 years |  |
Number of stock option awards exercised | shares |  | 23,796 | 111,774 | 104,514
Intrinsic value of stock options exercised |  | $ 87,000 | $ 701,000 | $ 903,000
Fair value of stock options exercised |  | 864,500 | 4,600,000 | 4,000,000.0
Cash received from the exercise of stock options |  | 777,500 | 3,900,000 | 3,100,000
Tax benefit from exercise of equity-based awards |  | $ 9,000 | 122,000 | 159,000
Restricted stock vesting percentage |  | 33.33% |  |
Intrinsic value of stock options outstanding |  | $ 51,777 | 105,665 | $ 529,000
Performance Stock |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Number of performance measures | item |  | 2 |  |
Weight of each performance measure |  | 50.00% |  |
Postretirement Life Insurance |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Liabilities for post retirement benefits payable to other beneficiaries |  | $ 12,300,000 | 13,300,000 |
Employees, Current and Former Members of Board of Directors |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Deferred compensation plans |  | $ 16,400,000 | $ 14,900,000 |
Maximum |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Number of shares authorized to be issued, maximum | shares | 4,000,000 |  |  |
Restricted Stock |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Restricted stock units, vesting terms |  | RSAs vest one-third on each of the first, second and third anniversaries from the date of the grant |  |
Restricted Stock and Performance Stock Awards | Minimum |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Vesting period of stock awards |  | 3 years |  |
1% through 3% |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Percentage of employer's match for 401(k) plan |  | 100.00% |  |
1% through 3% | Minimum |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Percentage of employee's gross pay for 401(k) plan |  | 1.00% |  |
1% through 3% | Maximum |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Percentage of employee's gross pay for 401(k) plan |  | 3.00% |  |
4% through 5% |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Percentage of employer's match for 401(k) plan |  | 50.00% |  |
4% through 5% | Minimum |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Percentage of employee's gross pay for 401(k) plan |  | 4.00% |  |
4% through 5% | Maximum |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Percentage of employee's gross pay for 401(k) plan |  | 5.00% |  |
Access National Bank |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Maximum term of stock options |  | 5 years |  |
Vesting period of stock awards |  | 4 years |  |

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