Condensed Consolidated Statements of Operations and Comprehensive Income - USD ($) shares in Millions, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Income Statement [Abstract]
Net sales	$ 292.2	$ 246.3	$ 824.1	$ 698.2
Cost of goods sold	181.5	155.1	521.0	447.9
Gross profit	110.7	91.2	303.1	250.3
Selling, general and administrative expenses	62.3	41.0	176.5	108.8
Change in fair value of contingent consideration	(0.3)	0.0	(9.8)	0.0
(Gain) related to sale of fixed and intangible assets	0.0	(6.9)	0.0	(21.0)
Equity (earnings) from joint venture	(23.4)	(15.2)	(68.1)	(48.2)
Operating income	72.1	72.3	204.5	210.7
Interest expense	6.1	6.1	17.4	18.7
Other non-operating (income) expense, net	(1.4)	(3.2)	(4.3)	361.8
Earnings (loss) from continuing operations before income taxes	67.4	69.4	191.4	(169.8)
Income tax expense (benefit)	16.6	15.2	48.0	(50.9)
Earnings (loss) from continuing operations	50.8	54.2	143.4	(118.9)
(Loss) from disposal of discontinued businesses, net of tax expense (benefit) of $ -, $ -, $1.7 and ($1.4)	0.0	(0.2)	(2.1)	(3.0)
Net (loss) from discontinued operations	0.0	(0.2)	(2.1)	(3.0)
Net earnings (loss)	50.8	54.0	141.3	(121.9)
Other comprehensive income, net of tax:
Foreign currency translation adjustments	(0.8)	(6.2)	0.3	(8.2)
Derivative gain (loss), net	0.8	1.5	5.7	(12.3)
Pension and postretirement adjustments	0.1	(0.8)	0.5	286.8
Total other comprehensive income (loss)	0.1	(5.5)	6.5	266.3
Total comprehensive income	$ 50.9	$ 48.5	$ 147.8	$ 144.4
Earnings (loss) per share of common stock, continuing operations:
Basic	$ 1.07	$ 1.13	$ 3.00	$ (2.48)
Diluted	1.06	1.13	2.98	(2.48)
Earnings (loss) per share of common stock, discontinued operations:
Basic			(0.04)	(0.06)
Diluted			(0.04)	(0.06)
Net earnings (loss) per share of common stock:
Basic	1.07	1.13	2.96	(2.54)
Diluted	$ 1.06	$ 1.13	$ 2.94	$ (2.54)
Average number of common shares outstanding:
Basic	47.5	47.9	47.7	47.9
Diluted	47.8	48.0	48.0	47.9