SUPPLEMENTAL GUARANTOR FINANCIAL INFORMATION (Statements of Operations) (Details) - USD ($) $ in Millions	3 Months Ended		48 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2020
Supplemental Guarantor Financial Information Statement of Operations [Line Items]
Sales	$ 1,425.1	$ 1,553.4
Operating expenses:
Cost of goods sold	1,374.2	1,347.3
Selling and administration	96.7	107.0
Restructuring charges	1.7	4.0	$ 242.0
Other operating (expense) income	0.0	0.1
Operating (loss) income	47.5	(95.2)
Equity (loss) income in subsidiaries	0.0	0.0
Interest expense	63.1	57.4
Interest income	0.1	0.2
Non-operating pension income (expense)	4.6	3.9
Other income	0.0	11.2
Income (loss) before taxes	(105.9)	53.1
Income tax (benefit) provision	(25.9)	11.4
Net (loss) income	(80.0)	41.7
Parent Guarantor
Supplemental Guarantor Financial Information Statement of Operations [Line Items]
Sales	353.3	332.8
Operating expenses:
Cost of goods sold	333.6	304.1
Selling and administration	39.9	51.8
Restructuring charges	0.0	1.4
Other operating (expense) income		(2.1)
Operating (loss) income	20.2	26.6
Equity (loss) income in subsidiaries	(48.5)	62.6
Interest expense	32.4	17.4
Interest income	2.1	0.6
Non-operating pension income (expense)	6.5	5.4
Other income		11.2
Income (loss) before taxes	(92.5)	35.8
Income tax (benefit) provision	(12.5)	(5.9)
Net (loss) income	(80.0)	41.7
Issuer
Supplemental Guarantor Financial Information Statement of Operations [Line Items]
Sales	0.0	0.0
Operating expenses:
Cost of goods sold	0.0	0.0
Selling and administration	0.0	0.0
Restructuring charges	0.0	0.0
Other operating (expense) income		0.0
Operating (loss) income	0.0	0.0
Equity (loss) income in subsidiaries	(31.1)	52.6
Interest expense	30.6	36.1
Interest income	0.0	0.0
Non-operating pension income (expense)	0.0	0.0
Other income		0.0
Income (loss) before taxes	(61.7)	16.5
Income tax (benefit) provision	(7.3)	(8.7)
Net (loss) income	(54.4)	25.2
Subsidiary Non-Guarantor
Supplemental Guarantor Financial Information Statement of Operations [Line Items]
Sales	1,201.8	1,327.7
Operating expenses:
Cost of goods sold	1,170.6	1,150.3
Selling and administration	56.8	55.2
Restructuring charges	1.7	2.6
Other operating (expense) income		2.2
Operating (loss) income	27.3	(121.8)
Equity (loss) income in subsidiaries	0.0	0.0
Interest expense	3.1	5.2
Interest income	1.0	0.9
Non-operating pension income (expense)	(1.9)	(1.5)
Other income		0.0
Income (loss) before taxes	(31.3)	116.0
Income tax (benefit) provision	(6.1)	26.0
Net (loss) income	(25.2)	90.0
Eliminations
Supplemental Guarantor Financial Information Statement of Operations [Line Items]
Sales	(130.0)	(107.1)
Operating expenses:
Cost of goods sold	(130.0)	(107.1)
Selling and administration	0.0	0.0
Restructuring charges	0.0	0.0
Other operating (expense) income		0.0
Operating (loss) income	0.0	0.0
Equity (loss) income in subsidiaries	79.6	(115.2)
Interest expense	(3.0)	(1.3)
Interest income	(3.0)	(1.3)
Non-operating pension income (expense)	0.0	0.0
Other income		0.0
Income (loss) before taxes	79.6	(115.2)
Income tax (benefit) provision	0.0	0.0
Net (loss) income	$ 79.6	$ (115.2)