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RETIREMENT AND POSTRETIREMENT PLANS - Employee Retirement Plan's investments measured at fair value (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Retirement Plans [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Assets | $ 47,857 |  |
Expected annual rates of return | 7.25% |  |
Percentage of investments for long term growth. | 97.00% |  |
Percentage of near term benefit payments | 3.00% |  |
Percentage of cumulative long term return on index | 9.00% |  |
Percentage of cumulative long term return on bonds | 5.00% |  |
Employee Retirement Plan's target allocation, expected annual rate of return | 7.25% |  |
Actuarial gain | $ (304) |  |
Retirement Plans [Member] | Cash and cash equivalents |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Assets | 1,581 |  |
Retirement Plans [Member] | U.S. large cap |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Assets | 13,623 |  |
Retirement Plans [Member] | U.S. mid cap/small cap |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Assets | 5,669 |  |
Retirement Plans [Member] | International |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Assets | 8,332 |  |
Retirement Plans [Member] | Equities blend |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Assets | 900 |  |
Retirement Plans [Member] | Corporate |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Assets | 1,696 |  |
Retirement Plans [Member] | Government |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Assets | 1,700 |  |
Retirement Plans [Member] | Mortgage-backed |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Assets | 2,549 |  |
Retirement Plans [Member] | High yield bonds and bond funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Assets | 11,807 |  |
Retirement Plans [Member] | Level 1 Inputs [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Assets | 30,224 |  |
Retirement Plans [Member] | Level 1 Inputs [Member] | U.S. large cap |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Assets | 13,623 |  |
Retirement Plans [Member] | Level 1 Inputs [Member] | U.S. mid cap/small cap |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Assets | 5,669 |  |
Retirement Plans [Member] | Level 1 Inputs [Member] | International |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Assets | 8,332 |  |
Retirement Plans [Member] | Level 1 Inputs [Member] | Equities blend |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Assets | 900 |  |
Retirement Plans [Member] | Level 1 Inputs [Member] | Government |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Assets | 1,700 |  |
Retirement Plans [Member] | Level 2 Inputs [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Assets | 17,633 |  |
Retirement Plans [Member] | Level 2 Inputs [Member] | Cash and cash equivalents |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Assets | 1,581 |  |
Retirement Plans [Member] | Level 2 Inputs [Member] | Corporate |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Assets | 1,696 |  |
Retirement Plans [Member] | Level 2 Inputs [Member] | Mortgage-backed |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Assets | 2,549 |  |
Retirement Plans [Member] | Level 2 Inputs [Member] | High yield bonds and bond funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Assets | 11,807 |  |
Employee Retirement Plan |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Assets | $ 28,693 | $ 27,142 | $ 25,202
Expected annual rates of return | 7.00% | 7.00% | 7.00%
Percentage of investments for long term growth. | 97.00% |  |
Percentage of near term benefit payments | 3.00% |  |
Percentage of cumulative long term return on index | 9.00% |  |
Percentage of cumulative long term return on bonds | 5.00% |  |
Employee Retirement Plan's target allocation, expected annual rate of return | 7.00% | 7.00% |
Actuarial gain | $ (903) | $ 2,204 |
Employee Retirement Plan | Cash and cash equivalents |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Assets | 1,001 | 720 |
Employee Retirement Plan | U.S. large cap |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Assets | 8,579 |  |
Employee Retirement Plan | U.S. mid cap/small cap |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Assets | 2,896 |  |
Employee Retirement Plan | International |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Assets | 3,560 |  |
Employee Retirement Plan | Equities blend |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Assets | 479 |  |
Employee Retirement Plan | Corporate |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Assets | 1,288 |  |
Employee Retirement Plan | Government |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Assets | 1,406 |  |
Employee Retirement Plan | Mortgage-backed |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Assets | 1,858 |  |
Employee Retirement Plan | High yield bonds and bond funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Assets | 7,626 |  |
Employee Retirement Plan | Domestic Large Cap |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Assets |  | 3,336 |
Employee Retirement Plan | Domestic Mid Cap |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Assets |  | 1,571 |
Employee Retirement Plan | Domestic Small Cap |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Assets |  | 618 |
Employee Retirement Plan | International Equity |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Assets |  | 4,678 |
Employee Retirement Plan | Fixed Income |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Assets |  | 8,300 |
Employee Retirement Plan | Domestic Large Cap. |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Assets |  | 5,564 |
Employee Retirement Plan | Domestic Mid Cap. |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Assets | 28,693 | 742 |
Employee Retirement Plan | Domestic Small Cap. |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Assets |  | 1,613 |
Employee Retirement Plan | Level 1 Inputs [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Assets |  | 19,223 |
Employee Retirement Plan | Level 1 Inputs [Member] | Cash and cash equivalents |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Assets |  | 720 |
Employee Retirement Plan | Level 1 Inputs [Member] | U.S. large cap |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Assets | 8,579 |  |
Employee Retirement Plan | Level 1 Inputs [Member] | U.S. mid cap/small cap |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Assets | 2,896 |  |
Employee Retirement Plan | Level 1 Inputs [Member] | International |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Assets | 3,560 |  |
Employee Retirement Plan | Level 1 Inputs [Member] | Equities blend |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Assets | 479 |  |
Employee Retirement Plan | Level 1 Inputs [Member] | Government |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Assets | 1,406 |  |
Employee Retirement Plan | Level 1 Inputs [Member] | Domestic Large Cap |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Assets |  | 3,336 |
Employee Retirement Plan | Level 1 Inputs [Member] | Domestic Mid Cap |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Assets |  | 1,571 |
Employee Retirement Plan | Level 1 Inputs [Member] | Domestic Small Cap |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Assets |  | 618 |
Employee Retirement Plan | Level 1 Inputs [Member] | International Equity |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Assets |  | 4,678 |
Employee Retirement Plan | Level 1 Inputs [Member] | Fixed Income |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Assets |  | 8,300 |
Employee Retirement Plan | Level 1 Inputs [Member] | Domestic Mid Cap. |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Assets | 16,920 |  |
Employee Retirement Plan | Level 2 Inputs [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Assets |  | 7,919 |
Employee Retirement Plan | Level 2 Inputs [Member] | Cash and cash equivalents |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Assets | 1,001 |  |
Employee Retirement Plan | Level 2 Inputs [Member] | Corporate |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Assets | 1,288 |  |
Employee Retirement Plan | Level 2 Inputs [Member] | Mortgage-backed |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Assets | 1,858 |  |
Employee Retirement Plan | Level 2 Inputs [Member] | High yield bonds and bond funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Assets | 7,626 |  |
Employee Retirement Plan | Level 2 Inputs [Member] | Domestic Large Cap. |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Assets |  | 5,564 |
Employee Retirement Plan | Level 2 Inputs [Member] | Domestic Mid Cap. |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Assets | $ 11,773 | 742 |
Employee Retirement Plan | Level 2 Inputs [Member] | Domestic Small Cap. |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Assets |  | $ 1,613 |

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