SUPPLEMENTAL GUARANTOR FINANCIAL INFORMATION (Statements of Operations) (Details) - USD ($) $ in Millions	3 Months Ended		52 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2019
Supplemental Guarantor Financial Information Statement of Operations [Line Items]
Sales	$ 1,553.4	$ 1,710.3
Operating expenses:
Cost of goods sold	1,347.3	1,528.7
Selling and administration	107.0	100.5
Restructuring charges	4.0	4.0	$ 186.0
Acquisition-related costs	0.0	0.3
Other operating (loss) income	0.1	8.1
Operating (loss) income	(95.2)	(84.9)
Earnings of non-consolidated affiliates	0.0	0.5
Equity income in subsidiaries	0.0	0.0
Interest expense	57.4	63.7
Interest income	0.2	0.4
Non-operating pension income (expense)	3.9	5.4
Other income	11.2	0.0
Income before taxes	53.1	27.5
Income tax (benefit) provision	11.4	6.6
Net income	41.7	20.9
Parent Guarantor
Supplemental Guarantor Financial Information Statement of Operations [Line Items]
Sales	332.8	352.7
Operating expenses:
Cost of goods sold	304.1	312.0
Selling and administration	51.8	47.1
Restructuring charges	1.4	0.0
Acquisition-related costs	0.0	0.3
Other operating (loss) income	(2.1)	5.8
Operating (loss) income	26.6	0.9
Earnings of non-consolidated affiliates		0.5
Equity income in subsidiaries	62.6	28.4
Interest expense	17.4	17.0
Interest income	0.6	1.0
Non-operating pension income (expense)	5.4	6.7
Other income	11.2
Income before taxes	35.8	18.7
Income tax (benefit) provision	(5.9)	(2.2)
Net income	41.7	20.9
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
Acquisition-related costs	0.0	0.0
Other operating (loss) income	0.0	0.0
Operating (loss) income	0.0	0.0
Earnings of non-consolidated affiliates		0.0
Equity income in subsidiaries	52.6	22.2
Interest expense	36.1	41.3
Interest income	0.0	0.0
Non-operating pension income (expense)	0.0	0.0
Other income	0.0
Income before taxes	16.5	(19.1)
Income tax (benefit) provision	(8.7)	(9.9)
Net income	25.2	(9.2)
Subsidiary Non-Guarantor
Supplemental Guarantor Financial Information Statement of Operations [Line Items]
Sales	1,327.7	1,467.0
Operating expenses:
Cost of goods sold	1,150.3	1,326.1
Selling and administration	55.2	53.4
Restructuring charges	2.6	4.0
Acquisition-related costs	0.0	0.0
Other operating (loss) income	2.2	2.3
Operating (loss) income	(121.8)	(85.8)
Earnings of non-consolidated affiliates		0.0
Equity income in subsidiaries	0.0	0.0
Interest expense	5.2	6.9
Interest income	0.9	0.9
Non-operating pension income (expense)	(1.5)	(1.3)
Other income	0.0
Income before taxes	116.0	78.5
Income tax (benefit) provision	26.0	18.7
Net income	90.0	59.8
Eliminations
Supplemental Guarantor Financial Information Statement of Operations [Line Items]
Sales	(107.1)	(109.4)
Operating expenses:
Cost of goods sold	(107.1)	(109.4)
Selling and administration	0.0	0.0
Restructuring charges	0.0	0.0
Acquisition-related costs	0.0	0.0
Other operating (loss) income	0.0	0.0
Operating (loss) income	0.0	0.0
Earnings of non-consolidated affiliates		0.0
Equity income in subsidiaries	(115.2)	(50.6)
Interest expense	(1.3)	(1.5)
Interest income	(1.3)	(1.5)
Non-operating pension income (expense)	0.0	0.0
Other income	0.0
Income before taxes	(115.2)	(50.6)
Income tax (benefit) provision	0.0	0.0
Net income	$ (115.2)	$ (50.6)