Financial Information for Subsidiary and Guarantor Parent (Cash Flow) (Details) - USD ($) $ in Millions	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017
Statement of Cash Flows
Cash flows provided by (used in) operating activities	$ 35.0	$ (85.5)
Investing Activities:
Purchases of property, plant and equipment	(70.6)	(55.3)
Net receipts/(payments) on intercompany activity	0.0	0.0
Asset disposals and other	0.8	3.3
Cash used in investing activities	(69.8)	(52.0)
Financing Activities:
Borrowings on long-term debt	7.1	7.3
Payments on long-term debt and capital leases	(2.8)	(0.8)
Net borrowings under credit facilities	3.4	59.4
Debt issuance costs	0.0	(0.8)
Net receipts/(payments) on intercompany activity	0.0	0.0
Sales to noncontrolling interests	14.4	2.2
Shares repurchased for income tax withholding on share-based compensation and other	(6.5)	(4.8)
Cash provided by financing activities	15.6	62.5
Decrease in cash and cash equivalents	(19.2)	(75.0)
Reportable Legal Entities \| Parent Company
Statement of Cash Flows
Cash flows provided by (used in) operating activities	(54.2)	(54.6)
Investing Activities:
Purchases of property, plant and equipment	(1.0)	0.0
Net receipts/(payments) on intercompany activity	0.0	0.0
Asset disposals and other	0.0	0.0
Cash used in investing activities	(1.0)	0.0
Financing Activities:
Borrowings on long-term debt	0.0	0.0
Payments on long-term debt and capital leases	(0.1)	(0.2)
Net borrowings under credit facilities	0.0	0.0
Debt issuance costs		0.0
Net receipts/(payments) on intercompany activity	61.6	59.8
Sales to noncontrolling interests	0.0	0.0
Shares repurchased for income tax withholding on share-based compensation and other	(6.5)	(4.8)
Cash provided by financing activities	55.0	54.8
Decrease in cash and cash equivalents	(0.2)	0.2
Reportable Legal Entities \| Subsidiary
Statement of Cash Flows
Cash flows provided by (used in) operating activities	(137.9)	(55.4)
Investing Activities:
Purchases of property, plant and equipment	(14.4)	(19.9)
Net receipts/(payments) on intercompany activity	0.0	0.0
Asset disposals and other	0.9	0.1
Cash used in investing activities	(13.5)	(19.8)
Financing Activities:
Borrowings on long-term debt	0.0	0.0
Payments on long-term debt and capital leases	(0.2)	(0.2)
Net borrowings under credit facilities	0.0	0.0
Debt issuance costs		0.0
Net receipts/(payments) on intercompany activity	135.5	75.5
Sales to noncontrolling interests	11.7	0.0
Shares repurchased for income tax withholding on share-based compensation and other	0.0	0.0
Cash provided by financing activities	147.0	75.3
Decrease in cash and cash equivalents	(4.4)	0.1
Reportable Legal Entities \| NonGuarantor Subsidiaries
Statement of Cash Flows
Cash flows provided by (used in) operating activities	227.1	24.5
Investing Activities:
Purchases of property, plant and equipment	(55.2)	(35.4)
Net receipts/(payments) on intercompany activity	(197.1)	(135.3)
Asset disposals and other	(0.1)	3.2
Cash used in investing activities	(252.4)	(167.5)
Financing Activities:
Borrowings on long-term debt	7.1	7.3
Payments on long-term debt and capital leases	(2.5)	(0.4)
Net borrowings under credit facilities	3.4	59.4
Debt issuance costs		(0.8)
Net receipts/(payments) on intercompany activity	0.0	0.0
Sales to noncontrolling interests	2.7	2.2
Shares repurchased for income tax withholding on share-based compensation and other	0.0	0.0
Cash provided by financing activities	10.7	67.7
Decrease in cash and cash equivalents	(14.6)	(75.3)
Eliminations
Statement of Cash Flows
Cash flows provided by (used in) operating activities	0.0	0.0
Investing Activities:
Purchases of property, plant and equipment	0.0	0.0
Net receipts/(payments) on intercompany activity	197.1	135.3
Asset disposals and other	0.0	0.0
Cash used in investing activities	197.1	135.3
Financing Activities:
Borrowings on long-term debt	0.0	0.0
Payments on long-term debt and capital leases	0.0	0.0
Net borrowings under credit facilities	0.0	0.0
Debt issuance costs		0.0
Net receipts/(payments) on intercompany activity	(197.1)	(135.3)
Sales to noncontrolling interests	0.0	0.0
Shares repurchased for income tax withholding on share-based compensation and other	0.0	0.0
Cash provided by financing activities	(197.1)	(135.3)
Decrease in cash and cash equivalents	$ 0.0	$ 0.0

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