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ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS) (Details of Accumulated Other Comprehensive Income (Loss) Components) (Details) - USD ($) $ in Millions | 3 Months Ended
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Mar. 31, 2019 | Mar. 31, 2018
Reclassification out of Accumulated Other Comprehensive Income [Member] |  |
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items] |  |
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net | $ 0.3 | $ (0.1)
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax | 5.7 | 6.1
Realized Gain Loss On Derivatives [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member] |  |
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items] |  |
TaxOnDerivativeInstrumentsGainLossReclassifiedFromAccumulatedOCIIntoEarnings | (0.1) | 0.0
Amount of gain/(loss) recognized in income on derivative | 0.2 | (0.1)
Accumulated Defined Benefit Plans Adjustment [Member] |  |
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items] |  |
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax | 5.5 | 6.2
Accumulated Defined Benefit Plans Adjustment [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member] |  |
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items] |  |
Prior service credits | (0.2) | (0.3)
Net actuarial loss | 7.2 | 6.5
Other Comprehensive Income (Loss), Reclassification, Pension and Other Postretirement Benefit Plans, Net Gain (Loss) Recognized in Net Periodic Benefit Cost, before Tax | 7.0 | 6.2
Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss) Arising During Period, Tax | (1.5) | 0.0
Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss), Reclassification Adjustment from AOCI, after Tax | $ 5.5 | $ 6.2

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- Definition Amount of gain (loss) recognized in net periodic benefit (cost) credit of defined benefit plan. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (h)(4) -URI http://asc.fasb.org/extlink&oid=108410482&loc=d3e1928-114920 Reference 2: 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=112275985&loc=d3e4179-114921 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 6 -Subparagraph (a)(4) -URI http://asc.fasb.org/extlink&oid=108410482&loc=d3e2709-114920 + Details
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- Definition Amount, before tax, of reclassification adjustment from accumulated other comprehensive income (loss) for gain (loss) of defined benefit plan. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=114867106&loc=d3e637-108580 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 15 -URI http://asc.fasb.org/extlink&oid=114867106&loc=d3e689-108580 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (i) -URI http://asc.fasb.org/extlink&oid=108410482&loc=d3e1928-114920 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 17A -URI http://asc.fasb.org/extlink&oid=114867106&loc=SL34724391-108580 + Details
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