FAIR VALUE MEASUREMENTS (Details) - USD ($) $ in Millions	6 Months Ended	12 Months Ended
Jun. 30, 2018	Dec. 31, 2017	Jun. 30, 2017
Fair Value Measurement [Abstract]
Transfers in (out) between levels	$ 0.0		$ 0.0
Fair value of total debt	117.9	$ 124.8
Carrying amount of long-term debt	115.5	122.7
Investments held in Rabbi Trust [Member]
Fair Value Measurement [Abstract]
Available-for-sale securities measured at fair value	1.5	1.5
Investments held in Rabbi Trust [Member] \| us-gaap_SupplementalEmployeeRetirementPlanDefinedBenefitMember
Fair Value Measurement [Abstract]
Gross unrealized gains associated with the investment held in the rabbi trust	0.2	0.2
Nonrecurring [Member]
Fair Value Measurement [Abstract]
Financial assets accounted at fair value	$ 0.0	$ 0.0

No definition available.

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- Definition

The amount of the transfers of assets or liabilities measured on a recurring basis between different levels of the fair value hierarchy.

+ References

No definition available.

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- Definition

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=99377789&loc=d3e19207-110258

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- Definition

Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=99377789&loc=d3e19207-110258

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- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (b)(3)
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(16))
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-Topic 210
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-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

+ References

No definition available.

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- Definition

Amount before tax and reclassification adjustments of unrealized holding gain (loss) on available-for-sale securities.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 45
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-Publisher FASB
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