Financial Information for Subsidiary and Guarantor Parent (Cash Flow) (Details) - USD ($) $ in Millions	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018
Statement of Cash Flows
Cash flows provided by (used in) operating activities	$ (10.0)	$ 116.6
Investing Activities:
Purchases of property, plant and equipment	(98.1)	(101.3)
Net receipts/(payments) on intercompany activity	0.0	0.0
Purchase of businesses	0.0	(10.0)
Proceeds from sale of businesses, net of transaction costs	155.9	0.0
Proceeds from disposal of property, plant and equipment	91.8	1.4
Other	(0.2)	0.8
Cash provided by (used in) investing activities	149.4	(109.1)
Financing Activities:
Borrowings on long-term debt	0.0	7.1
Payments on long-term debt and finance leases	(5.3)	(4.6)
Net borrowings under credit facilities	5.1	4.0
Net receipts/(payments) on intercompany activity	0.0	0.0
Dividends paid to stockholders		0.0
Dividends to noncontrolling interests	0.0	(10.0)
Sales to noncontrolling interests	0.0	14.4
Shares repurchased for income tax withholding on share-based compensation and other	(9.9)	(6.5)
Cash (used in) provided by financing activities	(10.1)	4.4
Increase in cash and cash equivalents	129.3	11.9
Reportable Legal Entities \| Parent Company
Statement of Cash Flows
Cash flows provided by (used in) operating activities	25.4	(102.9)
Investing Activities:
Purchases of property, plant and equipment	(0.5)	(1.4)
Net receipts/(payments) on intercompany activity	0.0	0.0
Purchase of businesses		0.0
Proceeds from sale of businesses, net of transaction costs	0.0
Proceeds from disposal of property, plant and equipment	0.0	0.0
Other	(0.2)	0.8
Cash provided by (used in) investing activities	(0.7)	(0.6)
Financing Activities:
Borrowings on long-term debt		0.0
Payments on long-term debt and finance leases	(0.4)	(0.2)
Net borrowings under credit facilities	0.0	0.0
Net receipts/(payments) on intercompany activity	(14.3)	109.2
Dividends paid to stockholders		0.0
Dividends to noncontrolling interests		0.0
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	(24.6)	102.5
Increase in cash and cash equivalents	0.1	(1.0)
Reportable Legal Entities \| Subsidiary
Statement of Cash Flows
Cash flows provided by (used in) operating activities	(167.1)	(126.7)
Investing Activities:
Purchases of property, plant and equipment	(15.1)	(19.2)
Net receipts/(payments) on intercompany activity	0.0	0.0
Purchase of businesses		0.0
Proceeds from sale of businesses, net of transaction costs	0.0
Proceeds from disposal of property, plant and equipment	0.0	1.3
Other	0.0	0.0
Cash provided by (used in) investing activities	(15.1)	(17.9)
Financing Activities:
Borrowings on long-term debt		0.0
Payments on long-term debt and finance leases	(0.1)	(0.6)
Net borrowings under credit facilities	0.0	0.0
Net receipts/(payments) on intercompany activity	181.4	126.8
Dividends paid to stockholders		0.0
Dividends to noncontrolling interests		0.0
Sales to noncontrolling interests		11.7
Shares repurchased for income tax withholding on share-based compensation and other	0.0	0.0
Cash (used in) provided by financing activities	181.3	137.9
Increase in cash and cash equivalents	(0.9)	(6.7)
Reportable Legal Entities \| NonGuarantor Subsidiaries
Statement of Cash Flows
Cash flows provided by (used in) operating activities	131.7	361.2
Investing Activities:
Purchases of property, plant and equipment	(82.5)	(80.7)
Net receipts/(payments) on intercompany activity	(167.1)	(236.0)
Purchase of businesses		(10.0)
Proceeds from sale of businesses, net of transaction costs	155.9
Proceeds from disposal of property, plant and equipment	91.8	0.1
Other	0.0	0.0
Cash provided by (used in) investing activities	(1.9)	(326.6)
Financing Activities:
Borrowings on long-term debt		7.1
Payments on long-term debt and finance leases	(4.8)	(3.8)
Net borrowings under credit facilities	5.1	4.0
Net receipts/(payments) on intercompany activity	0.0	0.0
Dividends paid to stockholders		(15.0)
Dividends to noncontrolling interests		(10.0)
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	0.3	(15.0)
Increase in cash and cash equivalents	130.1	19.6
Eliminations
Statement of Cash Flows
Cash flows provided by (used in) operating activities	0.0	(15.0)
Investing Activities:
Purchases of property, plant and equipment	0.0	0.0
Net receipts/(payments) on intercompany activity	167.1	236.0
Purchase of businesses		0.0
Proceeds from sale of businesses, net of transaction costs	0.0
Proceeds from disposal of property, plant and equipment	0.0	0.0
Other	0.0	0.0
Cash provided by (used in) investing activities	167.1	236.0
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	0.0
Net receipts/(payments) on intercompany activity	(167.1)	(236.0)
Dividends paid to stockholders		15.0
Dividends to noncontrolling interests		0.0
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	(167.1)	(221.0)
Increase in cash and cash equivalents	$ 0.0	$ 0.0

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