PENSION PLANS (Asset Allocations) (Details) - Pension Plan - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
PENSION AND SUPPLEMENTAL EXECUTIVE RETIREMENT PLANS
Asset allocations by asset category	100.00%	100.00%
Equity Securities
PENSION AND SUPPLEMENTAL EXECUTIVE RETIREMENT PLANS
Asset allocations by asset category	53.90%	50.60%
Equity securities included the entity's common stock	$ 0.1	$ 0.1
Debt Securities
PENSION AND SUPPLEMENTAL EXECUTIVE RETIREMENT PLANS
Asset allocations by asset category	42.30%	34.00%
Other
PENSION AND SUPPLEMENTAL EXECUTIVE RETIREMENT PLANS
Asset allocations by asset category	3.80%	15.40%

The amount of employer securities or securities of parties related to the employer that are included in plan assets.

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

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

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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