Financial Information for Subsidiary and Guarantor Parent (Cash Flow) (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Statement of Cash Flows
Cash flows provided by (used in) operating activities	$ (130.0)	$ (47.1)
Investing Activities:
Purchases of property, plant and equipment	(23.5)	(41.6)
Net receipts/(payments) on intercompany activity	0.0	0.0
Asset disposals and other	(0.1)	0.1
Cash used in investing activities	(23.6)	(41.5)
Financing Activities:
Borrowings on long-term debt	0.0	6.4
Payments on long-term debt and finance leases	(1.5)	(1.3)
Net borrowings under credit facilities	0.0	50.9
Net receipts/(payments) on intercompany activity	0.0	0.0
Sales to noncontrolling interests	0.0	7.4
Shares repurchased for income tax withholding on share-based compensation and other	(9.9)	(6.5)
Cash (used in) provided by financing activities	(11.4)	56.9
Decrease in cash and cash equivalents	(165.0)	(31.7)
Reportable Legal Entities \| Parent Company
Statement of Cash Flows
Cash flows provided by (used in) operating activities	(53.5)	(51.2)
Investing Activities:
Purchases of property, plant and equipment	(0.3)	(0.4)
Net receipts/(payments) on intercompany activity	0.0	0.0
Asset disposals and other	(0.1)	0.0
Cash used in investing activities	(0.4)	(0.4)
Financing Activities:
Borrowings on long-term debt		0.0
Payments on long-term debt and finance leases	(0.1)	(0.1)
Net borrowings under credit facilities		0.0
Net receipts/(payments) on intercompany activity	64.1	57.7
Sales to noncontrolling interests		0.0
Shares repurchased for income tax withholding on share-based compensation and other	(9.9)	(6.5)
Cash (used in) provided by financing activities	54.1	51.1
Decrease in cash and cash equivalents	0.2	(0.5)
Reportable Legal Entities \| Subsidiary
Statement of Cash Flows
Cash flows provided by (used in) operating activities	(115.8)	(36.1)
Investing Activities:
Purchases of property, plant and equipment	(2.4)	(7.3)
Net receipts/(payments) on intercompany activity	0.0	0.0
Asset disposals and other	0.0	0.1
Cash used in investing activities	(2.4)	(7.2)
Financing Activities:
Borrowings on long-term debt		0.0
Payments on long-term debt and finance leases	0.0	(0.1)
Net borrowings under credit facilities		0.0
Net receipts/(payments) on intercompany activity	119.9	30.4
Sales to noncontrolling interests		4.7
Shares repurchased for income tax withholding on share-based compensation and other	0.0	0.0
Cash (used in) provided by financing activities	119.9	35.0
Decrease in cash and cash equivalents	1.7	(8.3)
Reportable Legal Entities \| NonGuarantor Subsidiaries
Statement of Cash Flows
Cash flows provided by (used in) operating activities	39.3	40.2
Investing Activities:
Purchases of property, plant and equipment	(20.8)	(33.9)
Net receipts/(payments) on intercompany activity	(184.0)	(88.1)
Asset disposals and other	0.0	0.0
Cash used in investing activities	(204.8)	(122.0)
Financing Activities:
Borrowings on long-term debt		6.4
Payments on long-term debt and finance leases	(1.4)	(1.1)
Net borrowings under credit facilities		50.9
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 (used in) provided by financing activities	(1.4)	58.9
Decrease in cash and cash equivalents	(166.9)	(22.9)
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	184.0	88.1
Asset disposals and other	0.0	0.0
Cash used in investing activities	184.0	88.1
Financing Activities:
Borrowings on long-term debt		0.0
Payments on long-term debt and finance leases	0.0	0.0
Net borrowings under credit facilities		0.0
Net receipts/(payments) on intercompany activity	(184.0)	(88.1)
Sales to noncontrolling interests		0.0
Shares repurchased for income tax withholding on share-based compensation and other	0.0	0.0
Cash (used in) provided by financing activities	(184.0)	(88.1)
Decrease in cash and cash equivalents	$ 0.0	$ 0.0

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