EMPLOYEE BENEFITS - Allocation of Plan Assets (Details)	Dec. 31, 2017	Dec. 31, 2016
Defined Benefit Plan Disclosure [Line Items]
Actual asset allocations	100.00%	100.00%
Equity securities
Defined Benefit Plan Disclosure [Line Items]
Actual asset allocations	54.00%	49.60%
Equity securities \| Minimum
Defined Benefit Plan Disclosure [Line Items]
Minimum target asset allocation	48.00%
Equity securities \| Maximum
Defined Benefit Plan Disclosure [Line Items]
Minimum target asset allocation	58.00%
Debt securities
Defined Benefit Plan Disclosure [Line Items]
Actual asset allocations	45.00%	45.20%
Debt securities \| Minimum
Defined Benefit Plan Disclosure [Line Items]
Minimum target asset allocation	41.00%
Debt securities \| Maximum
Defined Benefit Plan Disclosure [Line Items]
Minimum target asset allocation	51.00%
Other
Defined Benefit Plan Disclosure [Line Items]
Actual asset allocations	1.00%	5.20%

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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/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (d)(5)(i)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

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Percentage of fair value of investments (categorized by debt securities, equity securities, real estate and other plan assets) to the fair value of plan assets held.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 5
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e2446-114920

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (d)(1)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

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