Supplemental Guarantor Financial Information - Condensed Consolidating Statements of Cash Flows (Details) - USD ($) $ in Millions	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017
Operating Activities
Cash (Used in) Provided by Operating Activities	$ (70.4)	$ 56.7
Investing Activities
Capital expenditures	(20.7)	(16.6)
Proceeds from the Divestiture	734.5	0.0
Proceeds from property dispositions	0.0	0.1
Intercompany contributions	0.0	0.0
Cash Provided by (Used in) Investing Activities	713.8	(16.5)
Financing Activities
Intercompany contributions	0.0	0.0
Debt repayments	(339.0)	0.0
Purchase of treasury stock	(0.6)	(2.0)
Proceeds from the exercise of stock options	11.4	0.8
Cash Used in Financing Activities	(328.2)	(1.2)
Effect of Exchange Rate Changes on Cash and Cash Equivalents	(3.8)	2.1
Increase in Cash, Cash Equivalents and Restricted Cash	311.4	41.1
Increase (Decrease) in Cash and Cash Equivalents		41.1
Cash and Cash Equivalents - Beginning of Period	219.7	113.7
Cash, Cash Equivalents and Restricted Cash - End of Period	531.1	154.8
Cash and Cash Equivalents, Beginning of Period	219.7	113.7
Cash and Cash Equivalents, End of Period	479.6	154.8
Eliminations
Operating Activities
Cash (Used in) Provided by Operating Activities	0.0	0.0
Investing Activities
Capital expenditures	0.0	0.0
Proceeds from the Divestiture	0.0
Proceeds from property dispositions		0.0
Intercompany contributions	(36.3)	55.1
Cash Provided by (Used in) Investing Activities	(36.3)	55.1
Financing Activities
Intercompany contributions	36.3	(55.1)
Debt repayments	0.0
Purchase of treasury stock	0.0	0.0
Proceeds from the exercise of stock options	0.0	0.0
Cash Used in Financing Activities	36.3	(55.1)
Effect of Exchange Rate Changes on Cash and Cash Equivalents	0.0	0.0
Increase in Cash, Cash Equivalents and Restricted Cash	0.0
Increase (Decrease) in Cash and Cash Equivalents		0.0
Cash and Cash Equivalents - Beginning of Period	0.0
Cash, Cash Equivalents and Restricted Cash - End of Period	0.0
Cash and Cash Equivalents, Beginning of Period	0.0	0.0
Cash and Cash Equivalents, End of Period	0.0	0.0
Parent \| Reportable legal entities
Operating Activities
Cash (Used in) Provided by Operating Activities	(114.2)	(21.1)
Investing Activities
Capital expenditures	0.0	0.0
Proceeds from the Divestiture	521.6
Proceeds from property dispositions		0.0
Intercompany contributions	0.0	0.0
Cash Provided by (Used in) Investing Activities	521.6	0.0
Financing Activities
Intercompany contributions	(32.3)	57.8
Debt repayments	(339.0)
Purchase of treasury stock	(0.6)	(2.0)
Proceeds from the exercise of stock options	11.4	0.8
Cash Used in Financing Activities	(360.5)	56.6
Effect of Exchange Rate Changes on Cash and Cash Equivalents	0.0	0.0
Increase in Cash, Cash Equivalents and Restricted Cash	46.9
Increase (Decrease) in Cash and Cash Equivalents		35.5
Cash and Cash Equivalents - Beginning of Period	114.5
Cash, Cash Equivalents and Restricted Cash - End of Period	161.4
Cash and Cash Equivalents, Beginning of Period	114.5	54.2
Cash and Cash Equivalents, End of Period	109.9	89.7
Guarantor Subsidiaries \| Reportable legal entities
Operating Activities
Cash (Used in) Provided by Operating Activities	31.3	73.7
Investing Activities
Capital expenditures	(15.0)	(13.0)
Proceeds from the Divestiture	9.0
Proceeds from property dispositions		0.1
Intercompany contributions	36.3	(55.1)
Cash Provided by (Used in) Investing Activities	30.3	(68.0)
Financing Activities
Intercompany contributions	0.0	0.0
Debt repayments	0.0
Purchase of treasury stock	0.0	0.0
Proceeds from the exercise of stock options	0.0	0.0
Cash Used in Financing Activities	0.0	0.0
Effect of Exchange Rate Changes on Cash and Cash Equivalents	0.1	0.3
Increase in Cash, Cash Equivalents and Restricted Cash	61.7
Increase (Decrease) in Cash and Cash Equivalents		6.0
Cash and Cash Equivalents - Beginning of Period	16.0
Cash, Cash Equivalents and Restricted Cash - End of Period	77.7
Cash and Cash Equivalents, Beginning of Period	16.0	9.5
Cash and Cash Equivalents, End of Period	77.7	15.5
Non-Guarantor Subsidiaries \| Reportable legal entities
Operating Activities
Cash (Used in) Provided by Operating Activities	12.5	4.1
Investing Activities
Capital expenditures	(5.7)	(3.6)
Proceeds from the Divestiture	203.9
Proceeds from property dispositions		0.0
Intercompany contributions	0.0	0.0
Cash Provided by (Used in) Investing Activities	198.2	(3.6)
Financing Activities
Intercompany contributions	(4.0)	(2.7)
Debt repayments	0.0
Purchase of treasury stock	0.0	0.0
Proceeds from the exercise of stock options	0.0	0.0
Cash Used in Financing Activities	(4.0)	(2.7)
Effect of Exchange Rate Changes on Cash and Cash Equivalents	(3.9)	1.8
Increase in Cash, Cash Equivalents and Restricted Cash	202.8
Increase (Decrease) in Cash and Cash Equivalents		(0.4)
Cash and Cash Equivalents - Beginning of Period	89.2
Cash, Cash Equivalents and Restricted Cash - End of Period	292.0
Cash and Cash Equivalents, Beginning of Period	89.2	50.0
Cash and Cash Equivalents, End of Period	$ 292.0	$ 49.6

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