EMPLOYEE RETIREMENT PLANS - Schedule of weighted average asset allocation (Details)	Dec. 31, 2019	Dec. 31, 2018
Asset Category:
Weighted Average Asset Allocation	100.00%	100.00%
Equity Securities [Member]
Asset Category:
Weighted Average Asset Allocation	55.00%	53.00%
Fixed Income Securities [Member]
Asset Category:
Weighted Average Asset Allocation	36.00%	40.00%
Other securities
Asset Category:
Weighted Average Asset Allocation	9.00%	7.00%

Percentage of actual investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one plan.

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)(i)
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920

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