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EMPLOYEE BENEFIT PLANS - Plan assets using fair value hierarchy (Details) - Retirement Income Plan - USD ($) $ in Thousands | Dec. 31, 2022 | Dec. 31, 2021
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Cash and Cash Equivalents |  |
EMPLOYEE BENEFIT PLANS |  |
Total Assets in the Fair Value Hierarchy | $ 129 | $ 87
Cash and Cash Equivalents | Level 1 |  |
EMPLOYEE BENEFIT PLANS |  |
Total Assets in the Fair Value Hierarchy | 129 | 87
Fixed Income Securities |  |
EMPLOYEE BENEFIT PLANS |  |
Total Assets in the Fair Value Hierarchy | 3,373 | 6,783
Fixed Income Securities | Level 2 |  |
EMPLOYEE BENEFIT PLANS |  |
Total Assets in the Fair Value Hierarchy | 3,373 | 6,783
Investment |  |
EMPLOYEE BENEFIT PLANS |  |
Total Assets in the Fair Value Hierarchy | 3,502 | 6,870
Investment | Level 1 |  |
EMPLOYEE BENEFIT PLANS |  |
Total Assets in the Fair Value Hierarchy | 129 | 87
Investment | Level 2 |  |
EMPLOYEE BENEFIT PLANS |  |
Total Assets in the Fair Value Hierarchy | $ 3,373 | $ 6,783

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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Definition Amount of investment within defined benefit plan asset category. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(ii) -URI https://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920 + Details
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