Condensed Consolidating Financial Information - Cash Flows (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
CASH FLOWS FROM OPERATING ACTIVITIES:
Net cash provided by (used in) operating activities	$ (21.5)	$ (33.0)
Net cash provided by (used in) investing activities
Purchase of property, plant and equipment	(10.6)	(3.5)
Intercompany transactions	0.0	0.0
Net cash provided by (used in) investing activities	(10.6)	(3.5)
Net cash provided by (used in) financing activities
Borrowings under revolving credit facilities	169.6	0.3
Repayments under revolving credit facilities	(157.6)	(0.3)
Other short term borrowings	3.4	0.0
Issuance of common stock	0.0	0.1
Intercompany transactions	0.0	0.0
Net cash provided by (used in) financing activities	15.4	0.1
CHANGE IN CASH, CASH EQUIVALENTS AND RESTRICTED CASH	(16.7)	(36.4)
Cash, cash equivalents and restricted cash, beginning of period	39.7	168.0
Cash, cash equivalents and restricted cash, end of period	23.0	131.6
Consolidating Adjustments [Member]
CASH FLOWS FROM OPERATING ACTIVITIES:
Net cash provided by (used in) operating activities		0.0
Net cash provided by (used in) investing activities
Purchase of property, plant and equipment	0.0	0.0
Intercompany transactions	32.8	23.8
Net cash provided by (used in) investing activities	32.8	23.8
Net cash provided by (used in) financing activities
Borrowings under revolving credit facilities	0.0	0.0
Repayments under revolving credit facilities	0.0	0.0
Other short term borrowings	0.0
Issuance of common stock		0.0
Intercompany transactions	(32.8)	(23.8)
Net cash provided by (used in) financing activities	(32.8)	(23.8)
CHANGE IN CASH, CASH EQUIVALENTS AND RESTRICTED CASH	0.0	0.0
Cash, cash equivalents and restricted cash, beginning of period	0.0	0.0
Cash, cash equivalents and restricted cash, end of period	0.0	0.0
The Company [Member] \| Reportable Legal Entities [Member]
CASH FLOWS FROM OPERATING ACTIVITIES:
Net cash provided by (used in) operating activities	(17.6)	(26.8)
Net cash provided by (used in) investing activities
Purchase of property, plant and equipment	(0.6)	(1.5)
Intercompany transactions	(15.2)	(23.8)
Net cash provided by (used in) investing activities	(15.8)	(25.3)
Net cash provided by (used in) financing activities
Borrowings under revolving credit facilities	169.6	0.3
Repayments under revolving credit facilities	(157.6)	(0.3)
Other short term borrowings	3.4
Issuance of common stock		0.1
Intercompany transactions	17.8	(3.8)
Net cash provided by (used in) financing activities	33.2	(3.7)
CHANGE IN CASH, CASH EQUIVALENTS AND RESTRICTED CASH	(0.2)	(55.8)
Cash, cash equivalents and restricted cash, beginning of period	0.1	64.3
Cash, cash equivalents and restricted cash, end of period	(0.1)	8.5
Combined Guarantor Subsidiaries [Member] \| Reportable Legal Entities [Member]
CASH FLOWS FROM OPERATING ACTIVITIES:
Net cash provided by (used in) operating activities	(5.3)	(26.8)
Net cash provided by (used in) investing activities
Purchase of property, plant and equipment	(6.8)	(0.4)
Intercompany transactions	(17.7)	0.0
Net cash provided by (used in) investing activities	(24.5)	(0.4)
Net cash provided by (used in) financing activities
Borrowings under revolving credit facilities	0.0	0.0
Repayments under revolving credit facilities	0.0	0.0
Other short term borrowings	0.0
Issuance of common stock		0.0
Intercompany transactions	29.9	27.2
Net cash provided by (used in) financing activities	29.9	27.2
CHANGE IN CASH, CASH EQUIVALENTS AND RESTRICTED CASH	0.1	0.0
Cash, cash equivalents and restricted cash, beginning of period	0.8	0.7
Cash, cash equivalents and restricted cash, end of period	0.9	0.7
Combined Non-Guarantor Subsidiaries [Member] \| Reportable Legal Entities [Member]
CASH FLOWS FROM OPERATING ACTIVITIES:
Net cash provided by (used in) operating activities	1.4	20.6
Net cash provided by (used in) investing activities
Purchase of property, plant and equipment	(3.2)	(1.6)
Intercompany transactions	0.1	0.0
Net cash provided by (used in) investing activities	(3.1)	(1.6)
Net cash provided by (used in) financing activities
Borrowings under revolving credit facilities	0.0	0.0
Repayments under revolving credit facilities	0.0	0.0
Other short term borrowings	0.0
Issuance of common stock		0.0
Intercompany transactions	(14.9)	0.4
Net cash provided by (used in) financing activities	(14.9)	0.4
CHANGE IN CASH, CASH EQUIVALENTS AND RESTRICTED CASH	(16.6)	19.4
Cash, cash equivalents and restricted cash, beginning of period	38.8	103.0
Cash, cash equivalents and restricted cash, end of period	$ 22.2	$ 122.4

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