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SHAREHOLDERS' EQUITY (Details of Accumulated Other Comprehensive Income (Loss) Components) (Details) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2018 | Mar. 31, 2018 | Jun. 30, 2017 | Mar. 31, 2017 | Jun. 30, 2018 | Jun. 30, 2017
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 |  |  |  |  | $ 0.1 |
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 | $ 0.0 |  | $ 0.0 |  | (0.1) | $ 0.0
Net loss reclassified from accumulated other comprehensive income (loss) | 6.5 |  | 6.5 |  | 12.6 | 12.9
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] |  |  |  |  |  |
Amount of gain/(loss) recognized in income on derivative | 0.0 |  | 0.0 |  | (0.1) | 0.0
Accumulated Defined Benefit Plans Adjustment [Member] |  |  |  |  |  |
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items] |  |  |  |  |  |
Net loss reclassified from accumulated other comprehensive income (loss) | 6.5 | $ 6.2 | 6.5 | $ 6.4 |  |
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 | (0.1) |  | (0.1) |  | (0.4) | (0.2)
Net actuarial loss | 6.6 |  | 6.6 |  | 13.1 | 13.1
Other Comprehensive Income (Loss), Reclassification, Pension and Other Postretirement Benefit Plans, Net Gain (Loss) Recognized in Net Periodic Benefit Cost, before Tax | $ 6.5 |  | $ 6.5 |  | $ 12.7 | $ 12.9

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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/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (h)(4) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 + Details
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- Definition Amount of prior service cost (credit) recognized in net periodic benefit cost (credit) of defined benefit 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 (h)(5) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 + Details
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- Definition Amount of increase (decrease) in the fair value of derivatives recognized in the income statement. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4A -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5618551-113959 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4C -Subparagraph (a),(c),(d),(e) -URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624171-113959 + Details
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- Definition The effective portion of net gain (loss) reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4C -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624171-113959 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4D -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624177-113959 + 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://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=84228862&loc=d3e637-108580 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 15 -URI http://asc.fasb.org/extlink&oid=84228862&loc=d3e689-108580 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (i) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 + Details
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