Condensed Consolidated Statements of Operations and Comprehensive Income - USD ($) shares in Millions, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Income Statement [Abstract]
Net sales	$ 203.2	$ 272.0	$ 451.9	$ 514.1
Cost of goods sold	135.4	168.6	292.8	319.3
Gross profit	67.8	103.4	159.1	194.8
Selling, general and administrative expenses	33.0	37.4	67.8	93.0
Gain on sale of fixed and intangible assets	(14.1)		(14.1)
Equity earnings from joint venture	(13.5)	(21.2)	(33.0)	(40.1)
Operating income	62.4	87.2	138.4	141.9
Interest expense	5.9	9.5	12.6	19.9
Other non-operating (income) expense, net	(4.4)	(5.4)	365.0	(10.9)
Earnings (loss) from continuing operations before income taxes	60.9	83.1	(239.2)	132.9
Income tax expense (benefit)	11.4	19.4	(66.1)	32.8
Earnings (loss) from continuing operations	49.5	63.7	(173.1)	100.1
Net (loss) from discontinued operations, net of tax expense of $ -, $4.8, $ - and $4.7		(2.3)		(1.8)
Earnings (loss) from disposal of discontinued businesses, net of tax expense (benefit) of $ -, $0.1, ($1.4) and $0.1	0.8	(6.9)	(2.8)	(4.7)
Net earnings (loss) from discontinued operations	0.8	(9.2)	(2.8)	(6.5)
Net earnings (loss)	50.3	54.5	(175.9)	93.6
Other comprehensive (loss) income, net of tax:
Foreign currency translation adjustments	0.1	0.7	(2.0)	6.0
Derivative (loss), net	(2.0)	(8.1)	(13.8)	(13.2)
Pension and postretirement adjustments	(0.7)	2.9	287.6	5.7
Total other comprehensive (loss) income	(2.6)	(4.5)	271.8	(1.5)
Total comprehensive income	$ 47.7	$ 50.0	$ 95.9	$ 92.1
Earnings (loss) per share of common stock, continuing operations:
Basic	$ 1.03	$ 1.30	$ (3.61)	$ 2.05
Diluted	1.03	1.28	(3.61)	2.01
Earnings (loss) per share of common stock, discontinued operations:
Basic	0.02	(0.19)	(0.06)	(0.13)
Diluted	0.02	(0.19)	(0.06)	(0.13)
Net earnings (loss) per share of common stock:
Basic	1.05	1.11	(3.67)	1.92
Diluted	$ 1.05	$ 1.09	$ (3.67)	$ 1.88
Average number of common shares outstanding:
Basic	47.8	49.0	47.9	48.8
Diluted	48.0	49.8	47.9	49.6