PENSION AND OTHER POSTRETIREMENT PLANS - Target Allocations for Plan Assets (Details)	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Target allocations for Plan assets
Percentage of Plan Assets	100.00%	100.00%
Cash and cash equivalents
Target allocations for Plan assets
Percentage of Plan Assets	5.60%	3.60%
Weighted-Average Expected Long-term Rate of Return (as a percent)	0.00%
Cash and cash equivalents \| Minimum
Target allocations for Plan assets
Target Allocation 2021 (as a percent)	0.00%
Cash and cash equivalents \| Maximum
Target allocations for Plan assets
Target Allocation 2021 (as a percent)	5.00%
Equity Securities
Target allocations for Plan assets
Percentage of Plan Assets	56.80%	57.90%
Weighted-Average Expected Long-term Rate of Return (as a percent)	9.50%
Equity Securities \| Minimum
Target allocations for Plan assets
Target Allocation 2021 (as a percent)	45.00%
Equity Securities \| Maximum
Target allocations for Plan assets
Target Allocation 2021 (as a percent)	65.00%
Fixed income securities
Target allocations for Plan assets
Percentage of Plan Assets	37.60%	38.50%
Weighted-Average Expected Long-term Rate of Return (as a percent)	5.00%
Fixed income securities \| Minimum
Target allocations for Plan assets
Target Allocation 2021 (as a percent)	30.00%
Fixed income securities \| Maximum
Target allocations for Plan assets
Target Allocation 2021 (as a percent)	50.00%

Represents the weighted-average expected long-term rate of return on target allocations for plan assets.

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- References

No definition available.

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- Definition

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.

+ References

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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- Definition

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.

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

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