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EMPLOYEE BENEFIT PLANS - Plan assets using fair value hierarchy (Details) - Retirement Income Plan - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Cash and Cash Equivalents
EMPLOYEE BENEFIT PLANS
Total Assets in the Fair Value Hierarchy	$ 87	$ 138
Cash and Cash Equivalents | Level 1
EMPLOYEE BENEFIT PLANS
Total Assets in the Fair Value Hierarchy	87	138
Fixed Income Securities
EMPLOYEE BENEFIT PLANS
Total Assets in the Fair Value Hierarchy	6,783	7,213
Fixed Income Securities | Level 2
EMPLOYEE BENEFIT PLANS
Total Assets in the Fair Value Hierarchy	6,783	7,213
Investment
EMPLOYEE BENEFIT PLANS
Total Assets in the Fair Value Hierarchy	6,870	7,351
Investment | Level 1
EMPLOYEE BENEFIT PLANS
Total Assets in the Fair Value Hierarchy	87	138
Investment | Level 2
EMPLOYEE BENEFIT PLANS
Total Assets in the Fair Value Hierarchy	$ 6,783	$ 7,213

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- Definition

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+ References

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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 http://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920

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