Condensed Consolidating Financial Information - Cash Flows (Details) - USD ($)	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018
CASH FLOWS FROM OPERATING ACTIVITIES:
Net cash provided by (used in) operating activities	$ (25,600,000)	$ (30,400,000)
Net cash provided by (used in) investing activities
Purchase of property, plant and equipment	(23,300,000)	(13,000,000.0)
Proceeds from sale of joint venture	10,500,000	0
Intercompany transactions	0	0
Net cash provided by (used in) investing activities	(12,800,000)	(13,000,000.0)
Net cash provided by (used in) financing activities
Borrowings under term loan	40,000,000.0	0
Borrowings under revolving credit facilities	288,200,000	0
Repayments under revolving credit facilities	(303,300,000)	0
Other short-term borrowings	3,400,000	0
Repayment on other short-term borrowings	(3,400,000)	0
Issuance of common stock	300,000	200,000
Intercompany transactions	0	0
Net cash provided by (used in) financing activities	25,200,000	200,000
CHANGE IN CASH, CASH EQUIVALENTS AND RESTRICTED CASH	(13,200,000)	(43,200,000)
Cash, cash equivalents and restricted cash, beginning of period	39,700,000	168,000,000.0
Cash, cash equivalents and restricted cash, end of period	26,500,000	124,800,000
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
Proceeds from sale of joint venture	0
Intercompany transactions	55,600,000	(27,000,000.0)
Net cash provided by (used in) investing activities	55,600,000	(27,000,000.0)
Net cash provided by (used in) financing activities
Borrowings under term loan	0
Borrowings under revolving credit facilities	0
Repayments under revolving credit facilities	0
Other short-term borrowings	0
Repayment on other short-term borrowings	0
Issuance of common stock	0	0
Intercompany transactions	(55,600,000)	27,000,000.0
Net cash provided by (used in) financing activities	(55,600,000)	27,000,000.0
CHANGE IN CASH, CASH EQUIVALENTS AND RESTRICTED CASH	0	0
Cash, cash equivalents and restricted cash, beginning of period	0	0
Cash, cash equivalents and restricted cash, end of period	0	0
The Company [Member] \| Reportable Legal Entities [Member]
CASH FLOWS FROM OPERATING ACTIVITIES:
Net cash provided by (used in) operating activities	(35,600,000)	(42,900,000)
Net cash provided by (used in) investing activities
Purchase of property, plant and equipment	(600,000)	(4,200,000)
Proceeds from sale of joint venture	0
Intercompany transactions	(22,200,000)	17,200,000
Net cash provided by (used in) investing activities	(22,800,000)	13,000,000.0
Net cash provided by (used in) financing activities
Borrowings under term loan	40,000,000.0
Borrowings under revolving credit facilities	288,200,000
Repayments under revolving credit facilities	(303,300,000)
Other short-term borrowings	3,400,000
Repayment on other short-term borrowings	(3,400,000)
Issuance of common stock	300,000	200,000
Intercompany transactions	33,700,000	(7,300,000)
Net cash provided by (used in) financing activities	58,900,000	(7,100,000)
CHANGE IN CASH, CASH EQUIVALENTS AND RESTRICTED CASH	500,000	(37,000,000.0)
Cash, cash equivalents and restricted cash, beginning of period	100,000	64,300,000
Cash, cash equivalents and restricted cash, end of period	600,000	27,300,000
Combined Guarantor Subsidiaries [Member] \| Reportable Legal Entities [Member]
CASH FLOWS FROM OPERATING ACTIVITIES:
Net cash provided by (used in) operating activities	(1,100,000)	(2,900,000)
Net cash provided by (used in) investing activities
Purchase of property, plant and equipment	(12,200,000)	(5,500,000)
Proceeds from sale of joint venture	0
Intercompany transactions	(33,600,000)	10,200,000
Net cash provided by (used in) investing activities	(45,800,000)	4,700,000
Net cash provided by (used in) financing activities
Borrowings under term loan	0
Borrowings under revolving credit facilities	0
Repayments under revolving credit facilities	0
Other short-term borrowings	0
Repayment on other short-term borrowings	0
Issuance of common stock	0	0
Intercompany transactions	46,800,000	(1,800,000)
Net cash provided by (used in) financing activities	46,800,000	(1,800,000)
CHANGE IN CASH, CASH EQUIVALENTS AND RESTRICTED CASH	(100,000)	0
Cash, cash equivalents and restricted cash, beginning of period	800,000	700,000
Cash, cash equivalents and restricted cash, end of period	700,000	700,000
Combined Non-Guarantor Subsidiaries [Member] \| Reportable Legal Entities [Member]
CASH FLOWS FROM OPERATING ACTIVITIES:
Net cash provided by (used in) operating activities	11,100,000	15,400,000
Net cash provided by (used in) investing activities
Purchase of property, plant and equipment	(10,500,000)	(3,300,000)
Proceeds from sale of joint venture	10,500,000
Intercompany transactions	200,000	(400,000)
Net cash provided by (used in) investing activities	200,000	(3,700,000)
Net cash provided by (used in) financing activities
Borrowings under term loan	0
Borrowings under revolving credit facilities	0
Repayments under revolving credit facilities	0
Other short-term borrowings	0
Repayment on other short-term borrowings	0
Issuance of common stock	0	0
Intercompany transactions	(24,900,000)	(17,900,000)
Net cash provided by (used in) financing activities	(24,900,000)	(17,900,000)
CHANGE IN CASH, CASH EQUIVALENTS AND RESTRICTED CASH	(13,600,000)	(6,200,000)
Cash, cash equivalents and restricted cash, beginning of period	38,800,000	103,000,000.0
Cash, cash equivalents and restricted cash, end of period	$ 25,200,000	$ 96,800,000

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