SUPPLEMENTAL GUARANTOR FINANCIAL INFORMATION (Cash Flows)(Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Supplemental Guarantor Financial Information Statements Of Cash Flows [Line Items]
Net Cash Provided by (Used in) Operating Activities	$ 80.9	$ 99.9
Capital expenditures	(89.5)	(83.0)
Proceeds from disposition of property, plant and equipment	0.1	0.0
Net investing activities	(89.4)	(83.0)
Borrowings	550.3	1,875.0
Repayments	(609.9)	(1,872.7)
Stock options exercised	1.0	8.8
Payments of Dividends	(33.4)	(33.1)
Debt issuance costs	(8.5)	(11.2)
Intercompany financing activities	0.0	0.0
Net financing activities	(100.5)	(33.2)
Effect of exchange rate changes on cash and cash equivalents	(0.3)	0.3
Net decrease in cash and cash equivalents	(109.3)	(16.0)
Cash and cash equivalents, end of period	109.1	168.5
Parent Guarantor
Supplemental Guarantor Financial Information Statements Of Cash Flows [Line Items]
Net Cash Provided by (Used in) Operating Activities	69.3	59.6
Capital expenditures	(41.7)	(24.1)
Proceeds from disposition of property, plant and equipment	0.0
Net investing activities	(41.7)	(24.1)
Borrowings	550.0	500.0
Repayments	(20.2)	(590.2)
Stock options exercised	1.0	8.8
Payments of Dividends	(33.4)	(33.1)
Debt issuance costs	(8.5)	(8.3)
Intercompany financing activities	(570.0)	89.6
Net financing activities	(81.1)	(33.2)
Effect of exchange rate changes on cash and cash equivalents	0.0	0.0
Net decrease in cash and cash equivalents	(53.5)	2.3
Cash and cash equivalents, end of period	3.6	27.5
Issuer
Supplemental Guarantor Financial Information Statements Of Cash Flows [Line Items]
Net Cash Provided by (Used in) Operating Activities	0.0	0.0
Capital expenditures	0.0	0.0
Proceeds from disposition of property, plant and equipment	0.0
Net investing activities	0.0	0.0
Borrowings	0.0	1,375.0
Repayments	(570.0)	(1,282.5)
Stock options exercised	0.0	0.0
Payments of Dividends	0.0	0.0
Debt issuance costs	0.0	(2.9)
Intercompany financing activities	570.0	(89.6)
Net financing activities	0.0	0.0
Effect of exchange rate changes on cash and cash equivalents	0.0	0.0
Net decrease in cash and cash equivalents	0.0	0.0
Cash and cash equivalents, end of period	0.0	0.0
Subsidiary Non-Guarantor
Supplemental Guarantor Financial Information Statements Of Cash Flows [Line Items]
Net Cash Provided by (Used in) Operating Activities	11.6	40.3
Capital expenditures	(47.8)	(58.9)
Proceeds from disposition of property, plant and equipment	0.1
Net investing activities	(47.7)	(58.9)
Borrowings	0.3	0.0
Repayments	(19.7)	0.0
Stock options exercised	0.0	0.0
Payments of Dividends	0.0	0.0
Debt issuance costs	0.0	0.0
Intercompany financing activities	0.0	0.0
Net financing activities	(19.4)	0.0
Effect of exchange rate changes on cash and cash equivalents	(0.3)	0.3
Net decrease in cash and cash equivalents	(55.8)	(18.3)
Cash and cash equivalents, end of period	105.5	141.0
Eliminations
Supplemental Guarantor Financial Information Statements Of Cash Flows [Line Items]
Net Cash Provided by (Used in) Operating Activities	0.0	0.0
Capital expenditures	0.0	0.0
Proceeds from disposition of property, plant and equipment	0.0
Net investing activities	0.0	0.0
Borrowings	0.0	0.0
Repayments	0.0	0.0
Stock options exercised	0.0	0.0
Payments of Dividends	0.0	0.0
Debt issuance costs	0.0	0.0
Intercompany financing activities	0.0	0.0
Net financing activities	0.0	0.0
Effect of exchange rate changes on cash and cash equivalents	0.0	0.0
Net decrease in cash and cash equivalents	0.0	0.0
Cash and cash equivalents, end of period	$ 0.0	$ 0.0

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[Line Items] for Supplemental Guarantor Financial Information Statements Of Cash Flows

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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

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Amount of increase (decrease) in cash and cash equivalents. Cash and cash equivalents are the amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Includes effect from exchange rate changes.

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Amount of increase (decrease) from the effect of exchange rate changes on cash and cash equivalent balances held in foreign currencies.

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Amount of cash inflow (outflow) from financing activities, including discontinued operations. Financing activity cash flows include obtaining resources from owners and providing them with a return on, and a return of, their investment; borrowing money and repaying amounts borrowed, or settling the obligation; and obtaining and paying for other resources obtained from creditors on long-term credit.

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Amount of cash inflow (outflow) from investing activities, including discontinued operations. Investing activity cash flows include making and collecting loans and acquiring and disposing of debt or equity instruments and property, plant, and equipment and other productive assets.

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Amount of cash inflow (outflow) from operating activities, including discontinued operations. Operating activity cash flows include transactions, adjustments, and changes in value not defined as investing or financing activities.

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The total of the cash outflow during the period which has been paid to third parties in connection with debt origination, which will be amortized over the remaining maturity period of the associated long-term debt and the cost incurred directly for the issuance of equity securities.

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Cash outflow in the form of capital distributions and dividends to common shareholders, preferred shareholders and noncontrolling interests.

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