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SHAREHOLDERS' EQUITY Details of Accumulated Other Comprehensive Income (Loss) Components (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2017 | Jun. 30, 2017 | Mar. 31, 2017 | Sep. 30, 2016 | Jun. 30, 2016 | Mar. 31, 2016 | Sep. 30, 2017 | Sep. 30, 2016
Reclassification out of Accumulated Other Comprehensive Income [Member] |  |  |  |  |  |  |  |
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items] |  |  |  |  |  |  |  |
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax | $ 6.8 |  |  | $ 7.4 |  |  | $ 19.7 | $ 19.9
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] |  |  |  |  |  |  |  |
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net | 0.0 |  |  | 1.2 |  |  | 0.0 | 1.2
TaxOnDerivativeInstrumentsGainLossReclassifiedFromAccumulatedOCIIntoEarnings | 0.0 |  |  | (0.5) |  |  | 0.0 | (0.5)
Amount of (gain)/loss recognized in income on derivative | 0.0 |  |  | 0.7 |  |  | 0.0 | 0.7
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 | 6.8 | $ 6.5 | $ 6.4 | 6.7 | $ 6.3 | $ 6.3 |  |
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) |  |  | (0.4) |  |  | (0.4) | (1.2)
Defined Benefit Plan, Amortization of Gain (Loss) | 7.0 |  |  | 7.1 |  |  | 20.1 | 20.4
Other Comprehensive Income (Loss), Reclassification, Pension and Other Postretirement Benefit Plans, Net Gain (Loss) Recognized in Net Periodic Benefit Cost, before Tax | 6.8 |  |  | 6.7 |  |  | 19.7 | 19.2
Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss) Arising During Period, Tax | 0.0 |  |  | 0.0 |  |  | 0.0 | 0.0
Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss), Reclassification Adjustment from AOCI, after Tax | $ 6.8 |  |  | $ 6.7 |  |  | $ 19.7 | $ 19.2

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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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- Definition Amount, after 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 15 -URI http://asc.fasb.org/extlink&oid=84228862&loc=d3e689-108580 Reference 2: 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 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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