SUPPLEMENTAL GUARANTOR FINANCIAL INFORMATION (Cash Flows)(Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015
Supplemental Guarantor Financial Information Statements Of Cash Flows [Line Items]
Net Cash Provided by (Used in) Operating Activities	$ 407.1	$ 115.1
Payments to Acquire Property, Plant, and Equipment	(199.4)	(79.7)
Business acquired in purchase transaction, net of cash acquired	(69.5)	0.0
Payments under long-term supply contract	(175.7)	0.0
Proceeds from sale/leaseback of equipment	40.4	0.0
Proceeds from disposition of property, plant and equipment	0.4	24.8
Proceeds from Contributions from Affiliates	6.6	6.6
Payments for (Proceeds from) Other Investing Activities	0.0	(2.8)
Net Cash Provided by (Used in) Investing Activities	(397.2)	(51.1)
Long-term debt repayments	(176.1)	(3.2)
Stock options exercised	0.4	2.2
Excess tax benefits from stock-based compensation	0.0	0.4
Payments of Dividends	(99.1)	(46.5)
Debt and equity issuance costs	(0.8)	(19.7)
Intercompany Financing Activities	0.0
Net Cash Provided by (Used in) Financing Activities	(275.6)	(66.8)
Effect of exchange rate changes on cash and cash equivalents	0.7	0.0
Cash and Cash Equivalents, Period Increase (Decrease)	(265.0)	(2.8)
Cash and cash equivalents, end of period	127.0	254.0
Parent Guarantor
Supplemental Guarantor Financial Information Statements Of Cash Flows [Line Items]
Net Cash Provided by (Used in) Operating Activities	409.0	102.2
Payments to Acquire Property, Plant, and Equipment	(39.2)	(57.6)
Business acquired in purchase transaction, net of cash acquired	(69.5)
Payments under long-term supply contract	0.0
Proceeds from sale/leaseback of equipment	0.0
Proceeds from disposition of property, plant and equipment	0.1	0.4
Proceeds from Contributions from Affiliates	6.6	6.6
Payments for (Proceeds from) Other Investing Activities		0.0
Net Cash Provided by (Used in) Investing Activities	(102.0)	(50.6)
Long-term debt repayments	(125.5)	(3.2)
Stock options exercised	0.4	2.2
Excess tax benefits from stock-based compensation		0.4
Payments of Dividends	(99.1)	(46.5)
Debt and equity issuance costs	0.0	(19.7)
Intercompany Financing Activities	(186.7)
Net Cash Provided by (Used in) Financing Activities	(410.9)	(66.8)
Effect of exchange rate changes on cash and cash equivalents	0.0
Cash and Cash Equivalents, Period Increase (Decrease)	(103.9)	(15.2)
Cash and cash equivalents, end of period	15.5	224.2
Issuer
Supplemental Guarantor Financial Information Statements Of Cash Flows [Line Items]
Net Cash Provided by (Used in) Operating Activities	0.0	0.0
Payments to Acquire Property, Plant, and Equipment	0.0	0.0
Business acquired in purchase transaction, net of cash acquired	0.0
Payments under long-term supply contract	0.0
Proceeds from sale/leaseback of equipment	0.0
Proceeds from disposition of property, plant and equipment	0.0	0.0
Proceeds from Contributions from Affiliates	0.0	0.0
Payments for (Proceeds from) Other Investing Activities		0.0
Net Cash Provided by (Used in) Investing Activities	0.0	0.0
Long-term debt repayments	(50.6)	0.0
Stock options exercised	0.0	0.0
Excess tax benefits from stock-based compensation		0.0
Payments of Dividends	0.0	0.0
Debt and equity issuance costs	(0.8)	0.0
Intercompany Financing Activities	51.4
Net Cash Provided by (Used in) Financing Activities	0.0	0.0
Effect of exchange rate changes on cash and cash equivalents	0.0
Cash and Cash Equivalents, Period Increase (Decrease)	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	(1.9)	12.9
Payments to Acquire Property, Plant, and Equipment	(160.2)	(22.1)
Business acquired in purchase transaction, net of cash acquired	0.0
Payments under long-term supply contract	(175.7)
Proceeds from sale/leaseback of equipment	40.4
Proceeds from disposition of property, plant and equipment	0.3	24.4
Proceeds from Contributions from Affiliates	0.0	0.0
Payments for (Proceeds from) Other Investing Activities		(2.8)
Net Cash Provided by (Used in) Investing Activities	(295.2)	(0.5)
Long-term debt repayments	0.0	0.0
Stock options exercised	0.0	0.0
Excess tax benefits from stock-based compensation		0.0
Payments of Dividends	0.0	0.0
Debt and equity issuance costs	0.0	0.0
Intercompany Financing Activities	135.3
Net Cash Provided by (Used in) Financing Activities	135.3	0.0
Effect of exchange rate changes on cash and cash equivalents	0.7
Cash and Cash Equivalents, Period Increase (Decrease)	(161.1)	12.4
Cash and cash equivalents, end of period	111.5	29.8
Eliminations
Supplemental Guarantor Financial Information Statements Of Cash Flows [Line Items]
Net Cash Provided by (Used in) Operating Activities	0.0	0.0
Payments to Acquire Property, Plant, and Equipment	0.0	0.0
Business acquired in purchase transaction, net of cash acquired	0.0
Payments under long-term supply contract	0.0
Proceeds from sale/leaseback of equipment	0.0
Proceeds from disposition of property, plant and equipment	0.0	0.0
Proceeds from Contributions from Affiliates	0.0	0.0
Payments for (Proceeds from) Other Investing Activities		0.0
Net Cash Provided by (Used in) Investing Activities	0.0	0.0
Long-term debt repayments	0.0	0.0
Stock options exercised	0.0	0.0
Excess tax benefits from stock-based compensation		0.0
Payments of Dividends	0.0	0.0
Debt and equity issuance costs	0.0	0.0
Intercompany Financing Activities	0.0
Net Cash Provided by (Used in) Financing Activities	0.0	0.0
Effect of exchange rate changes on cash and cash equivalents	0.0
Cash and Cash Equivalents, Period Increase (Decrease)	0.0	0.0
Cash and cash equivalents, end of period	$ 0.0	$ 0.0