Supplemental Condensed Consolidating Financial Information - Consolidating Statement of Cash Flows (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Cash Flows from Operating Activities:
Net income	$ 12.6	$ 0.4
Adjustments to reconcile net (loss) income to net cash (used in) provided by operating activities:
Asset impairment	10.7	0.0
Depreciation and amortization expense:	28.2	23.8
Deferred income tax expense	3.2	3.1
Gain on curtailment and payments in excess of expense for postretirement plan benefits	(0.6)	(4.7)
Share-based compensation expense	1.7	1.5
Loss from equity method investment	0.0	0.7
Equity in Earnings Loss of Subsidiaries	0.0	0.0
(Gain) loss on extinguishment of debt	(20.4)	9.4
Changes in working capital pertaining to operating activities (net of changes in held for sale working capital):
Receivables	(7.0)	16.7
Inventories	14.2	11.5
Accounts payable	(5.8)	(13.5)
Accrued liabilities	9.4	(16.7)
Interest payable	(11.6)	(11.2)
Income taxes	(0.6)	(2.8)
Other	(4.6)	(7.1)
Net cash provided by operating activities	29.4	11.1
Cash Flows from Investing Activities:
Capital expenditures	(13.8)	(8.3)
Decrease in restricted cash	7.9	0.0
Other investing activities	0.6	0.0
Net cash used in continuing investing activities	(5.3)	(8.3)
Cash Flows from Financing Activities:
Proceeds from issuance of long-term debt	0.0	210.8
Repayment of long-term debt	(32.9)	(149.5)
Debt issuance costs	0.0	(4.2)
Proceeds from revolving facility	20.0	0.0
Repayment of revolving facility	(20.0)	0.0
Cash distribution to noncontrolling interests	(12.3)	(9.1)
Shares repurchased	0.0	(20.0)
Proceeds from exercise of stock options, net of shares withheld for taxes	(0.5)	(0.5)
Dividends paid	0.0	(3.9)
Net increase (decrease) in advances from affiliate	0.0	0.0
Net cash (used in) provided by financing activities	(45.7)	23.6
Net (decrease) increase in cash and cash equivalents	(21.6)	26.4
Cash and cash equivalents at beginning of period	123.4	139.0
Cash and cash equivalents at end of period	101.8	165.4
Issuer
Cash Flows from Operating Activities:
Net income	(4.1)	(4.0)
Adjustments to reconcile net (loss) income to net cash (used in) provided by operating activities:
Asset impairment	0.0
Depreciation and amortization expense:	0.0	0.0
Deferred income tax expense	0.3	(0.2)
Gain on curtailment and payments in excess of expense for postretirement plan benefits	0.0	0.0
Share-based compensation expense	1.7	1.5
Loss from equity method investment		0.0
Equity in Earnings Loss of Subsidiaries	(0.7)	0.0
(Gain) loss on extinguishment of debt	0.0	0.0
Changes in working capital pertaining to operating activities (net of changes in held for sale working capital):
Receivables	0.0	0.1
Inventories	0.0	0.0
Accounts payable	0.0	0.0
Accrued liabilities	0.1	0.0
Interest payable	(0.8)	(6.2)
Income taxes	0.0	(0.7)
Other	1.4	(0.1)
Net cash provided by operating activities	(2.1)	(9.6)
Cash Flows from Investing Activities:
Capital expenditures	0.0	0.0
Decrease in restricted cash	0.0
Other investing activities	0.0
Net cash used in continuing investing activities	0.0	0.0
Cash Flows from Financing Activities:
Proceeds from issuance of long-term debt		0.0
Repayment of long-term debt	0.0	0.0
Debt issuance costs		0.0
Proceeds from revolving facility	0.0
Repayment of revolving facility	0.0
Cash distribution to noncontrolling interests	0.0	0.0
Shares repurchased		(20.0)
Proceeds from exercise of stock options, net of shares withheld for taxes	(0.5)	(0.5)
Dividends paid		(3.9)
Net increase (decrease) in advances from affiliate	2.6	34.0
Net cash (used in) provided by financing activities	2.1	9.6
Net (decrease) increase in cash and cash equivalents	0.0	0.0
Cash and cash equivalents at beginning of period	0.0	0.0
Cash and cash equivalents at end of period	0.0	0.0
Guarantor Subsidiaries
Cash Flows from Operating Activities:
Net income	4.9	3.7
Adjustments to reconcile net (loss) income to net cash (used in) provided by operating activities:
Asset impairment	0.0
Depreciation and amortization expense:	2.2	2.1
Deferred income tax expense	5.7	0.5
Gain on curtailment and payments in excess of expense for postretirement plan benefits	(0.3)	(0.3)
Share-based compensation expense	0.0	0.0
Loss from equity method investment		0.0
Equity in Earnings Loss of Subsidiaries	(11.3)	(3.4)
(Gain) loss on extinguishment of debt	0.0	0.0
Changes in working capital pertaining to operating activities (net of changes in held for sale working capital):
Receivables	(0.8)	5.1
Inventories	0.2	(3.8)
Accounts payable	(0.5)	(5.8)
Accrued liabilities	0.3	(3.8)
Interest payable	0.0	0.0
Income taxes	0.1	12.0
Other	2.6	(3.3)
Net cash provided by operating activities	3.1	3.0
Cash Flows from Investing Activities:
Capital expenditures	(1.9)	(1.5)
Decrease in restricted cash	0.0
Other investing activities	0.0
Net cash used in continuing investing activities	(1.9)	(1.5)
Cash Flows from Financing Activities:
Proceeds from issuance of long-term debt		0.0
Repayment of long-term debt	0.0	0.0
Debt issuance costs		0.0
Proceeds from revolving facility	0.0
Repayment of revolving facility	0.0
Cash distribution to noncontrolling interests	0.0	0.0
Shares repurchased		0.0
Proceeds from exercise of stock options, net of shares withheld for taxes	0.0	0.0
Dividends paid		0.0
Net increase (decrease) in advances from affiliate	(10.7)	(34.3)
Net cash (used in) provided by financing activities	(10.7)	(34.3)
Net (decrease) increase in cash and cash equivalents	(9.5)	(32.8)
Cash and cash equivalents at beginning of period	70.6	102.3
Cash and cash equivalents at end of period	61.1	69.5
Non- Guarantor Subsidiaries
Cash Flows from Operating Activities:
Net income	23.8	4.1
Adjustments to reconcile net (loss) income to net cash (used in) provided by operating activities:
Asset impairment	10.7
Depreciation and amortization expense:	26.0	21.7
Deferred income tax expense	(2.8)	2.8
Gain on curtailment and payments in excess of expense for postretirement plan benefits	(0.3)	(4.4)
Share-based compensation expense	0.0	0.0
Loss from equity method investment		0.7
Equity in Earnings Loss of Subsidiaries	0.0	0.0
(Gain) loss on extinguishment of debt	(20.4)	9.4
Changes in working capital pertaining to operating activities (net of changes in held for sale working capital):
Receivables	(6.2)	11.5
Inventories	14.0	15.3
Accounts payable	(5.3)	(7.7)
Accrued liabilities	9.0	(12.9)
Interest payable	(10.8)	(5.0)
Income taxes	(0.7)	(14.1)
Other	(8.6)	(3.7)
Net cash provided by operating activities	28.4	17.7
Cash Flows from Investing Activities:
Capital expenditures	(11.9)	(6.8)
Decrease in restricted cash	7.9
Other investing activities	0.6
Net cash used in continuing investing activities	(3.4)	(6.8)
Cash Flows from Financing Activities:
Proceeds from issuance of long-term debt		210.8
Repayment of long-term debt	(32.9)	(149.5)
Debt issuance costs		(4.2)
Proceeds from revolving facility	20.0
Repayment of revolving facility	(20.0)
Cash distribution to noncontrolling interests	(12.3)	(9.1)
Shares repurchased		0.0
Proceeds from exercise of stock options, net of shares withheld for taxes	0.0	0.0
Dividends paid		0.0
Net increase (decrease) in advances from affiliate	8.1	0.3
Net cash (used in) provided by financing activities	(37.1)	48.3
Net (decrease) increase in cash and cash equivalents	(12.1)	59.2
Cash and cash equivalents at beginning of period	52.8	36.7
Cash and cash equivalents at end of period	40.7	95.9
Combining and Consolidating Adjustments
Cash Flows from Operating Activities:
Net income	(12.0)	(3.4)
Adjustments to reconcile net (loss) income to net cash (used in) provided by operating activities:
Asset impairment	0.0
Depreciation and amortization expense:	0.0	0.0
Deferred income tax expense	0.0	0.0
Gain on curtailment and payments in excess of expense for postretirement plan benefits	0.0	0.0
Share-based compensation expense	0.0	0.0
Loss from equity method investment		0.0
Equity in Earnings Loss of Subsidiaries	12.0	3.4
(Gain) loss on extinguishment of debt	0.0	0.0
Changes in working capital pertaining to operating activities (net of changes in held for sale working capital):
Receivables	0.0	0.0
Inventories	0.0	0.0
Accounts payable	0.0	0.0
Accrued liabilities	0.0	0.0
Interest payable	0.0	0.0
Income taxes	0.0	0.0
Other	0.0	0.0
Net cash provided by operating activities	0.0	0.0
Cash Flows from Investing Activities:
Capital expenditures	0.0	0.0
Decrease in restricted cash	0.0
Other investing activities	0.0
Net cash used in continuing investing activities	0.0	0.0
Cash Flows from Financing Activities:
Proceeds from issuance of long-term debt		0.0
Repayment of long-term debt	0.0	0.0
Debt issuance costs		0.0
Proceeds from revolving facility	0.0
Repayment of revolving facility	0.0
Cash distribution to noncontrolling interests	0.0	0.0
Shares repurchased		0.0
Proceeds from exercise of stock options, net of shares withheld for taxes	0.0	0.0
Dividends paid		$ 0.0
Net increase (decrease) in advances from affiliate	0.0
Net cash (used in) provided by financing activities	0.0	$ 0.0
Net (decrease) increase in cash and cash equivalents	0.0	0.0
Cash and cash equivalents at beginning of period	0.0	0.0
Cash and cash equivalents at end of period	$ 0.0	$ 0.0