Financial Information for Subsidiary and Guarantor Parent (Cash Flow) (Details) - USD ($) $ in Millions	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017
Statement of Cash Flows
Cash flows provided by (used in) operating activities	$ 116.6	$ (53.8)
Investing Activities:
Purchases of property, plant and equipment	(101.3)	(85.3)
Net receipts/(payments) on intercompany activity	0.0	0.0
Purchases of businesses	(10.0)	0.0
Asset disposals and other	2.2	3.2
Cash used in investing activities	(109.1)	(82.1)
Financing Activities:
Borrowings on long-term debt	7.1	8.5
Payments on long-term debt and capital leases	(4.6)	(1.9)
Net borrowings under credit facilities	4.0	28.0
Debt issuance costs	0.0	(0.8)
Net receipts/(payments) on intercompany activity	0.0	0.0
Dividends paid to stockholders	0.0
Dividends paid to noncontrolling interests	(10.0)	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	4.4	31.2
Increase (decrease) in cash and cash equivalents	11.9	(104.7)
Reportable Legal Entities \| Parent Company
Statement of Cash Flows
Cash flows provided by (used in) operating activities	(102.9)	(84.2)
Investing Activities:
Purchases of property, plant and equipment	(1.4)	(0.5)
Net receipts/(payments) on intercompany activity	0.0	0.0
Purchases of businesses	0.0
Asset disposals and other	0.8	0.0
Cash used in investing activities	(0.6)	(0.5)
Financing Activities:
Borrowings on long-term debt	0.0	0.0
Payments on long-term debt and capital leases	(0.2)	(0.3)
Net borrowings under credit facilities	0.0	0.0
Debt issuance costs		0.0
Net receipts/(payments) on intercompany activity	109.2	89.6
Dividends paid to stockholders	0.0
Dividends paid to noncontrolling interests	0.0
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	102.5	84.5
Increase (decrease) in cash and cash equivalents	(1.0)	(0.2)
Reportable Legal Entities \| Subsidiary
Statement of Cash Flows
Cash flows provided by (used in) operating activities	(126.7)	(83.1)
Investing Activities:
Purchases of property, plant and equipment	(19.2)	(27.4)
Net receipts/(payments) on intercompany activity	0.0	0.0
Purchases of businesses	0.0
Asset disposals and other	1.3	0.1
Cash used in investing activities	(17.9)	(27.3)
Financing Activities:
Borrowings on long-term debt	0.0	0.0
Payments on long-term debt and capital leases	(0.6)	(0.2)
Net borrowings under credit facilities	0.0	0.0
Debt issuance costs		0.0
Net receipts/(payments) on intercompany activity	126.8	115.5
Dividends paid to stockholders	0.0
Dividends paid to noncontrolling interests	0.0
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	137.9	115.3
Increase (decrease) in cash and cash equivalents	(6.7)	4.9
Reportable Legal Entities \| NonGuarantor Subsidiaries
Statement of Cash Flows
Cash flows provided by (used in) operating activities	361.2	113.5
Investing Activities:
Purchases of property, plant and equipment	(80.7)	(57.4)
Net receipts/(payments) on intercompany activity	(236.0)	(205.1)
Purchases of businesses	(10.0)
Asset disposals and other	0.1	3.1
Cash used in investing activities	(326.6)	(259.4)
Financing Activities:
Borrowings on long-term debt	7.1	8.5
Payments on long-term debt and capital leases	(3.8)	(1.4)
Net borrowings under credit facilities	4.0	28.0
Debt issuance costs		(0.8)
Net receipts/(payments) on intercompany activity	0.0	0.0
Dividends paid to stockholders	(15.0)
Dividends paid to noncontrolling interests	(10.0)
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	(15.0)	36.5
Increase (decrease) in cash and cash equivalents	19.6	(109.4)
Eliminations
Statement of Cash Flows
Cash flows provided by (used in) operating activities	(15.0)	0.0
Investing Activities:
Purchases of property, plant and equipment	0.0	0.0
Net receipts/(payments) on intercompany activity	236.0	205.1
Purchases of businesses	0.0
Asset disposals and other	0.0	0.0
Cash used in investing activities	236.0	205.1
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	(236.0)	(205.1)
Dividends paid to stockholders	15.0
Dividends paid to noncontrolling interests	0.0
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	(221.0)	(205.1)
Increase (decrease) in cash and cash equivalents	$ 0.0	$ 0.0

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