Condensed Consolidating Financial Information - Cash Flows (Details) - USD ($) $ in Millions	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018
CASH FLOWS FROM OPERATING ACTIVITIES:
Net cash provided by (used in) operating activities	$ (4.4)	$ (59.0)
Net cash provided by (used in) investing activities
Purchase of property, plant and equipment	(39.9)	(49.3)
Proceeds from sale of joint venture	10.5	0.0
Intercompany transactions	0.0	0.0
Net cash provided by (used in) investing activities	(29.4)	(49.3)
Net cash provided by (used in) financing activities
Borrowings under term loan	40.0	0.0
Borrowings under revolving credit facilities	314.6	14.3
Repayments under revolving credit facilities	(337.5)	0.0
Other short-term borrowings	3.4	0.0
Repayment on other short-term borrowings	(3.4)	0.0
Issuance of common stock	0.3	0.2
Intercompany transactions	0.0	0.0
Net cash provided by (used in) financing activities	17.4	14.5
CHANGE IN CASH, CASH EQUIVALENTS AND RESTRICTED CASH	(16.4)	(93.8)
Cash, cash equivalents and restricted cash, beginning of period	39.7	168.0
Cash, cash equivalents and restricted cash, end of period	23.3	74.2
Consolidating Adjustments [Member]
CASH FLOWS FROM OPERATING ACTIVITIES:
Net cash provided by (used in) operating activities	0.0	0.0
Net cash provided by (used in) investing activities
Purchase of property, plant and equipment	0.0	0.0
Proceeds from sale of joint venture	0.0
Intercompany transactions	59.9	(80.0)
Net cash provided by (used in) investing activities	59.9	(80.0)
Net cash provided by (used in) financing activities
Borrowings under term loan	0.0
Borrowings under revolving credit facilities	0.0	0.0
Repayments under revolving credit facilities	0.0
Other short-term borrowings	0.0
Repayment on other short-term borrowings	0.0
Issuance of common stock	0.0	0.0
Intercompany transactions	(59.9)	80.0
Net cash provided by (used in) financing activities	(59.9)	80.0
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	(57.1)	(51.2)
Net cash provided by (used in) investing activities
Purchase of property, plant and equipment	(0.6)	(4.0)
Proceeds from sale of joint venture	0.0
Intercompany transactions	(9.3)	39.5
Net cash provided by (used in) investing activities	(9.9)	35.5
Net cash provided by (used in) financing activities
Borrowings under term loan	40.0
Borrowings under revolving credit facilities	295.1	14.3
Repayments under revolving credit facilities	(318.0)
Other short-term borrowings	3.4
Repayment on other short-term borrowings	(3.4)
Issuance of common stock	0.3	0.2
Intercompany transactions	51.0	(37.1)
Net cash provided by (used in) financing activities	68.4	(22.6)
CHANGE IN CASH, CASH EQUIVALENTS AND RESTRICTED CASH	1.4	(38.3)
Cash, cash equivalents and restricted cash, beginning of period	0.1	64.3
Cash, cash equivalents and restricted cash, end of period	1.5	26.0
Combined Guarantor Subsidiaries [Member] \| Reportable Legal Entities [Member]
CASH FLOWS FROM OPERATING ACTIVITIES:
Net cash provided by (used in) operating activities	45.0	(0.5)
Net cash provided by (used in) investing activities
Purchase of property, plant and equipment	(26.4)	(38.9)
Proceeds from sale of joint venture	0.0
Intercompany transactions	(52.6)	40.9
Net cash provided by (used in) investing activities	(79.0)	2.0
Net cash provided by (used in) financing activities
Borrowings under term loan	0.0
Borrowings under revolving credit facilities	0.0	0.0
Repayments under revolving credit facilities	0.0
Other short-term borrowings	0.0
Repayment on other short-term borrowings	0.0
Issuance of common stock	0.0	0.0
Intercompany transactions	34.0	(1.7)
Net cash provided by (used in) financing activities	34.0	(1.7)
CHANGE IN CASH, CASH EQUIVALENTS AND RESTRICTED CASH	0.0	(0.2)
Cash, cash equivalents and restricted cash, beginning of period	0.8	0.7
Cash, cash equivalents and restricted cash, end of period	0.8	0.5
Combined Non-Guarantor Subsidiaries [Member] \| Reportable Legal Entities [Member]
CASH FLOWS FROM OPERATING ACTIVITIES:
Net cash provided by (used in) operating activities	7.7	(7.3)
Net cash provided by (used in) investing activities
Purchase of property, plant and equipment	(12.9)	(6.4)
Proceeds from sale of joint venture	10.5
Intercompany transactions	2.0	(0.4)
Net cash provided by (used in) investing activities	(0.4)	(6.8)
Net cash provided by (used in) financing activities
Borrowings under term loan	0.0
Borrowings under revolving credit facilities	19.5	0.0
Repayments under revolving credit facilities	(19.5)
Other short-term borrowings	0.0
Repayment on other short-term borrowings	0.0
Issuance of common stock	0.0	0.0
Intercompany transactions	(25.1)	(41.2)
Net cash provided by (used in) financing activities	(25.1)	(41.2)
CHANGE IN CASH, CASH EQUIVALENTS AND RESTRICTED CASH	(17.8)	(55.3)
Cash, cash equivalents and restricted cash, beginning of period	38.8	103.0
Cash, cash equivalents and restricted cash, end of period	$ 21.0	$ 47.7

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