Financial Information for Subsidiary and Guarantor Parent (Cash Flow) (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Statement of Cash Flows
Cash flows provided by (used in) operating activities	$ (47.1)	$ (110.2)
Investing Activities:
Purchases of property, plant and equipment	(41.6)	(24.8)
Net receipts/(payments) on intercompany activity	0.0	0.0
Asset disposals and other	0.1	2.6
Cash used in investing activities	(41.5)	(22.2)
Financing Activities:
Borrowings on long-term debt	6.4	0.0
Payments on long-term debt and capital leases	(1.3)	(0.3)
Net borrowings under credit facilities	50.9	67.7
Net receipts/(payments) on intercompany activity	0.0	0.0
Sales to noncontrolling interests	7.4	0.0
Shares repurchased for income tax withholding on share-based compensation and other	(6.5)	(4.8)
Cash provided by financing activities	56.9	62.6
Decrease in cash and cash equivalents	(31.7)	(69.8)
Reportable Legal Entities \| Parent Company
Statement of Cash Flows
Cash flows provided by (used in) operating activities	(51.2)	(40.7)
Investing Activities:
Purchases of property, plant and equipment	(0.4)	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	(0.4)	0.0
Financing Activities:
Borrowings on long-term debt	0.0
Payments on long-term debt and capital leases	(0.1)	(0.1)
Net borrowings under credit facilities	0.0	0.0
Net receipts/(payments) on intercompany activity	57.7	45.6
Sales to noncontrolling interests	0.0
Shares repurchased for income tax withholding on share-based compensation and other	(6.5)	(4.8)
Cash provided by financing activities	51.1	40.7
Decrease in cash and cash equivalents	(0.5)	0.0
Reportable Legal Entities \| Subsidiary
Statement of Cash Flows
Cash flows provided by (used in) operating activities	(36.1)	0.5
Investing Activities:
Purchases of property, plant and equipment	(7.3)	(8.7)
Net receipts/(payments) on intercompany activity	0.0	0.0
Asset disposals and other	0.1	0.1
Cash used in investing activities	(7.2)	(8.6)
Financing Activities:
Borrowings on long-term debt	0.0
Payments on long-term debt and capital leases	(0.1)	(0.1)
Net borrowings under credit facilities	0.0	0.0
Net receipts/(payments) on intercompany activity	30.4	13.5
Sales to noncontrolling interests	4.7
Shares repurchased for income tax withholding on share-based compensation and other	0.0	0.0
Cash provided by financing activities	35.0	13.4
Decrease in cash and cash equivalents	(8.3)	5.3
Reportable Legal Entities \| NonGuarantor Subsidiaries
Statement of Cash Flows
Cash flows provided by (used in) operating activities	40.2	(70.0)
Investing Activities:
Purchases of property, plant and equipment	(33.9)	(16.1)
Net receipts/(payments) on intercompany activity	(88.1)	(59.1)
Asset disposals and other	0.0	2.5
Cash used in investing activities	(122.0)	(72.7)
Financing Activities:
Borrowings on long-term debt	6.4
Payments on long-term debt and capital leases	(1.1)	(0.1)
Net borrowings under credit facilities	50.9	67.7
Net receipts/(payments) on intercompany activity	0.0	0.0
Sales to noncontrolling interests	2.7
Shares repurchased for income tax withholding on share-based compensation and other	0.0	0.0
Cash provided by financing activities	58.9	67.6
Decrease in cash and cash equivalents	(22.9)	(75.1)
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	88.1	59.1
Asset disposals and other	0.0	0.0
Cash used in investing activities	88.1	59.1
Financing Activities:
Borrowings on long-term debt	0.0
Payments on long-term debt and capital leases	0.0	0.0
Net borrowings under credit facilities	0.0	0.0
Net receipts/(payments) on intercompany activity	(88.1)	(59.1)
Sales to noncontrolling interests	0.0
Shares repurchased for income tax withholding on share-based compensation and other	0.0	0.0
Cash provided by financing activities	(88.1)	(59.1)
Decrease in cash and cash equivalents	$ 0.0	$ 0.0

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