EMPLOYEE BENEFITS - Schedule of Long-term Rates of Return on Pension and PBOP (Details)	Dec. 31, 2019	Dec. 31, 2018
United States
Defined Contribution Plan Disclosure [Line Items]
Target Asset Allocation	15.00%	15.00%
Assumed Rate of Return	8.50%	8.50%
Global
Defined Contribution Plan Disclosure [Line Items]
Target Asset Allocation	10.00%	10.00%
Assumed Rate of Return	8.75%	8.75%
Non-United States
Defined Contribution Plan Disclosure [Line Items]
Target Asset Allocation	8.00%	8.00%
Assumed Rate of Return	8.50%	8.50%
Emerging Markets
Defined Contribution Plan Disclosure [Line Items]
Target Asset Allocation	4.00%	4.00%
Assumed Rate of Return	10.00%	10.00%
Fixed Income
Defined Contribution Plan Disclosure [Line Items]
Target Asset Allocation	13.00%	13.00%
Assumed Rate of Return	4.00%	4.00%
Public High Yield Fixed Income
Defined Contribution Plan Disclosure [Line Items]
Target Asset Allocation	4.00%	4.00%
Assumed Rate of Return	6.50%	6.50%
Private Debt
Defined Contribution Plan Disclosure [Line Items]
Target Asset Allocation	15.00%	15.00%
Assumed Rate of Return	9.00%	9.00%
Private Equity
Defined Contribution Plan Disclosure [Line Items]
Target Asset Allocation	15.00%	15.00%
Assumed Rate of Return	12.00%	12.00%
Real Assets
Defined Contribution Plan Disclosure [Line Items]
Target Asset Allocation	16.00%	16.00%
Assumed Rate of Return	7.50%	7.50%

Percentage of target 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/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 55
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=118257860&loc=d3e4179-114921

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-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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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.

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 20
-Section 50
-Paragraph 1
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