Financial Information for Subsidiary and Guarantor Parent (Cash Flows) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Condensed Financial Statements, Captions [Line Items]
Cash flows provided by (used in) operating activities	$ 392.8	$ 22.4	$ (43.7)
Purchases of property, plant and equipment	(139.2)	(122.7)	(202.2)
Net receipts (payments) on intercompany activity	0.0	0.0	0.0
Purchases of businesses	(10.0)	0.0	0.0
Asset disposals and other	4.1	3.1	2.2
Cash flows provided by (used in) investing activities	(145.1)	(119.6)	(200.0)
Borrowings on long-term debt	7.1	8.5	387.5
Payments on long-term debt and capital leases	(6.4)	(353.0)	(2.7)
Net (payments) borrowings under credit facilities	(5.9)	1.6	3.1
Debt issuance costs	0.0	(0.8)	(10.4)
Debt extinguishment charge	0.0	(35.8)	0.0
Net receipts (payments) on intercompany activity	0.0	0.0	0.0
Issuance of common stock	0.0	397.8	0.0
Dividends paid to stockholders	0.0	0.0	(25.8)
Dividends paid to noncontrolling interests	(10.0)	(8.0)	(16.0)
Sale to noncontrolling interest	14.4	3.7	0.0
Payments to Noncontrolling Interests	0.0	0.0	(12.2)
Shares repurchased for income tax withholding on share-based compensation	(6.5)	(4.8)	0.0
Cash (used in) provided by financing activities	(7.3)	9.2	323.5
Increase (decrease) in cash and cash equivalents	240.4	(88.0)	79.8
Legal Entities [Member] \| Guarantor Parent [Member]
Condensed Financial Statements, Captions [Line Items]
Cash flows provided by (used in) operating activities	(107.0)	(78.8)	(78.5)
Purchases of property, plant and equipment	(2.1)	(0.9)	(0.5)
Net receipts (payments) on intercompany activity	0.0	0.0	0.0
Purchases of businesses	0.0
Asset disposals and other	1.3	0.0	0.0
Cash flows provided by (used in) investing activities	(0.8)	(0.9)	(0.5)
Borrowings on long-term debt	0.0	0.0	287.5
Payments on long-term debt and capital leases	(0.2)	(350.4)	(0.7)
Net (payments) borrowings under credit facilities	0.0	0.0	0.0
Debt issuance costs		0.0	(9.4)
Debt extinguishment charge		(35.8)
Net receipts (payments) on intercompany activity	112.5	72.7	(170.7)
Issuance of common stock		397.8
Dividends paid to stockholders	0.0	0.0	(25.8)
Dividends paid to noncontrolling interests	0.0	0.0	0.0
Sale to noncontrolling interest	0.0	0.0
Payments to Noncontrolling Interests			0.0
Shares repurchased for income tax withholding on share-based compensation	(6.5)	(4.8)
Cash (used in) provided by financing activities	105.8	79.5	80.9
Increase (decrease) in cash and cash equivalents	(2.0)	(0.2)	1.9
Legal Entities [Member] \| Subsidiary [Member]
Condensed Financial Statements, Captions [Line Items]
Cash flows provided by (used in) operating activities	(223.9)	(101.5)	(232.3)
Purchases of property, plant and equipment	(26.2)	(38.5)	(98.7)
Net receipts (payments) on intercompany activity	0.0	0.0	0.0
Purchases of businesses	0.0
Asset disposals and other	2.6	0.1	0.2
Cash flows provided by (used in) investing activities	(23.6)	(38.4)	(98.5)
Borrowings on long-term debt	0.0	0.0	0.0
Payments on long-term debt and capital leases	(0.9)	(0.3)	(0.2)
Net (payments) borrowings under credit facilities	0.0	0.0	0.0
Debt issuance costs		0.0	0.0
Debt extinguishment charge		0.0
Net receipts (payments) on intercompany activity	234.0	151.2	330.7
Issuance of common stock		0.0
Dividends paid to stockholders	0.0	0.0	0.0
Dividends paid to noncontrolling interests	0.0	0.0	0.0
Sale to noncontrolling interest	11.7	0.0
Payments to Noncontrolling Interests			0.0
Shares repurchased for income tax withholding on share-based compensation	0.0	0.0
Cash (used in) provided by financing activities	244.8	150.9	330.5
Increase (decrease) in cash and cash equivalents	(2.7)	11.0	(0.3)
Legal Entities [Member] \| Non-Guarantor Subsidiaries [Member]
Condensed Financial Statements, Captions [Line Items]
Cash flows provided by (used in) operating activities	738.7	214.7	291.1
Purchases of property, plant and equipment	(110.9)	(83.3)	(103.0)
Net receipts (payments) on intercompany activity	(346.5)	(223.9)	(160.0)
Purchases of businesses	(10.0)
Asset disposals and other	0.2	3.0	2.0
Cash flows provided by (used in) investing activities	(467.2)	(304.2)	(261.0)
Borrowings on long-term debt	7.1	8.5	100.0
Payments on long-term debt and capital leases	(5.3)	(2.3)	(1.8)
Net (payments) borrowings under credit facilities	(5.9)	1.6	3.1
Debt issuance costs		(0.8)	(1.0)
Debt extinguishment charge		0.0
Net receipts (payments) on intercompany activity	0.0	0.0	0.0
Issuance of common stock		0.0
Dividends paid to stockholders	(15.0)	(12.0)	(24.0)
Dividends paid to noncontrolling interests	(10.0)	(8.0)	(16.0)
Sale to noncontrolling interest	2.7	3.7
Payments to Noncontrolling Interests			(12.2)
Shares repurchased for income tax withholding on share-based compensation	0.0	0.0
Cash (used in) provided by financing activities	(26.4)	(9.3)	48.1
Increase (decrease) in cash and cash equivalents	245.1	(98.8)	78.2
Eliminations [Member]
Condensed Financial Statements, Captions [Line Items]
Cash flows provided by (used in) operating activities	(15.0)	(12.0)	(24.0)
Purchases of property, plant and equipment	0.0	0.0	0.0
Net receipts (payments) on intercompany activity	346.5	223.9	160.0
Purchases of businesses	0.0
Asset disposals and other	0.0	0.0	0.0
Cash flows provided by (used in) investing activities	346.5	223.9	160.0
Borrowings on long-term debt	0.0	0.0	0.0
Payments on long-term debt and capital leases	0.0	0.0	0.0
Net (payments) borrowings under credit facilities	0.0	0.0	0.0
Debt issuance costs		0.0	0.0
Debt extinguishment charge		0.0
Net receipts (payments) on intercompany activity	(346.5)	(223.9)	(160.0)
Issuance of common stock		0.0
Dividends paid to stockholders	15.0	12.0	24.0
Dividends paid to noncontrolling interests	0.0	0.0	0.0
Sale to noncontrolling interest	0.0	0.0
Payments to Noncontrolling Interests			0.0
Shares repurchased for income tax withholding on share-based compensation	0.0	0.0
Cash (used in) provided by financing activities	(331.5)	(211.9)	(136.0)
Increase (decrease) in cash and cash equivalents	$ 0.0	$ 0.0	$ 0.0

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