Condensed Consolidating Financial Information - Cash Flows (Details) - USD ($) $ in Millions	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019
CASH FLOWS FROM OPERATING ACTIVITIES:
Net cash provided by (used in) operating activities	$ 71.6	$ (25.6)
Net cash provided by (used in) investing activities
Purchase of property, plant and equipment	(9.6)	(23.3)
Proceeds from sale of joint venture		10.5
Proceeds from sales of property, plant & equipment	0.1	0.0
Intercompany transactions	0.0	0.0
Net cash provided by (used in) investing activities	(9.5)	(12.8)
Net cash provided by (used in) financing activities
Repayments on term loan	(10.0)	0.0
Borrowing under term loan	0.0	40.0
Borrowings under revolving credit facilities	122.4	288.2
Repayments under revolving credit facilities	(36.4)	(303.3)
Other short term borrowings		3.4
Repayment on other short-term borrowings	0.0	(3.4)
Issuance of common stock	0.0	0.3
Intercompany transactions	0.0	0.0
Net cash provided by (used in) financing activities	76.0	25.2
CHANGE IN CASH, CASH EQUIVALENTS AND RESTRICTED CASH	138.1	(13.2)
Cash, cash equivalents and restricted cash, beginning of period	39.7	39.7
Cash, cash equivalents and restricted cash, end of period	177.8	26.5
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
Proceeds from sales of property, plant & equipment	0.0
Intercompany transactions	18.1	55.6
Net cash provided by (used in) investing activities	18.1	55.6
Net cash provided by (used in) financing activities
Repayments on term loan	0.0
Borrowing under term loan		0.0
Borrowings under revolving credit facilities	0.0	0.0
Repayments under revolving credit facilities	0.0	0.0
Other short term borrowings		0.0
Repayment on other short-term borrowings		0.0
Issuance of common stock		0.0
Intercompany transactions	(18.1)	(55.6)
Net cash provided by (used in) financing activities	(18.1)	(55.6)
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	(21.6)	(35.6)
Net cash provided by (used in) investing activities
Purchase of property, plant and equipment	(0.5)	(0.6)
Proceeds from sale of joint venture		0.0
Proceeds from sales of property, plant & equipment	0.0
Intercompany transactions	38.4	(22.2)
Net cash provided by (used in) investing activities	37.9	(22.8)
Net cash provided by (used in) financing activities
Repayments on term loan	(10.0)
Borrowing under term loan		40.0
Borrowings under revolving credit facilities	77.4	288.2
Repayments under revolving credit facilities	(36.4)	(303.3)
Other short term borrowings		3.4
Repayment on other short-term borrowings		(3.4)
Issuance of common stock		0.3
Intercompany transactions	56.1	33.7
Net cash provided by (used in) financing activities	87.1	58.9
CHANGE IN CASH, CASH EQUIVALENTS AND RESTRICTED CASH	103.4	0.5
Cash, cash equivalents and restricted cash, beginning of period	0.3	0.1
Cash, cash equivalents and restricted cash, end of period	103.7	0.6
Combined Guarantor Subsidiaries [Member] \| Reportable Legal Entities [Member]
CASH FLOWS FROM OPERATING ACTIVITIES:
Net cash provided by (used in) operating activities	66.8	(1.1)
Net cash provided by (used in) investing activities
Purchase of property, plant and equipment	(8.3)	(12.2)
Proceeds from sale of joint venture		0.0
Proceeds from sales of property, plant & equipment	0.0
Intercompany transactions	(56.3)	(33.6)
Net cash provided by (used in) investing activities	(64.6)	(45.8)
Net cash provided by (used in) financing activities
Repayments on term loan	0.0
Borrowing under term loan		0.0
Borrowings under revolving credit facilities	0.0	0.0
Repayments under revolving credit facilities	0.0	0.0
Other short term borrowings		0.0
Repayment on other short-term borrowings		0.0
Issuance of common stock		0.0
Intercompany transactions	(1.1)	46.8
Net cash provided by (used in) financing activities	(1.1)	46.8
CHANGE IN CASH, CASH EQUIVALENTS AND RESTRICTED CASH	1.1	(0.1)
Cash, cash equivalents and restricted cash, beginning of period	0.9	0.8
Cash, cash equivalents and restricted cash, end of period	2.0	0.7
Combined Non-Guarantor Subsidiaries [Member] \| Reportable Legal Entities [Member]
CASH FLOWS FROM OPERATING ACTIVITIES:
Net cash provided by (used in) operating activities	26.4	11.1
Net cash provided by (used in) investing activities
Purchase of property, plant and equipment	(0.8)	(10.5)
Proceeds from sale of joint venture		10.5
Proceeds from sales of property, plant & equipment	0.1
Intercompany transactions	(0.2)	0.2
Net cash provided by (used in) investing activities	(0.9)	0.2
Net cash provided by (used in) financing activities
Repayments on term loan	0.0
Borrowing under term loan		0.0
Borrowings under revolving credit facilities	45.0	0.0
Repayments under revolving credit facilities	0.0	0.0
Other short term borrowings		0.0
Repayment on other short-term borrowings		0.0
Issuance of common stock		0.0
Intercompany transactions	(36.9)	(24.9)
Net cash provided by (used in) financing activities	8.1	(24.9)
CHANGE IN CASH, CASH EQUIVALENTS AND RESTRICTED CASH	33.6	(13.6)
Cash, cash equivalents and restricted cash, beginning of period	38.5	38.8
Cash, cash equivalents and restricted cash, end of period	$ 72.1	$ 25.2

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