Discontinued Operations (Financial Results) (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2021	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Operating profit	$ 87.1	$ 138.2	$ 136.9	$ 140.1	$ 53.9	$ 75.9	$ 28.7	$ 81.7	$ 502.3	$ 240.2	$ 183.1
Miscellaneous expense, net									20.5	14.9	4.9
Income from discontinued operations, net of tax	$ 3.3	$ 5.2	$ 27.6	$ 5.0	$ 4.3	$ 7.2	$ 1.4	$ 5.0	41.1	17.9	21.0
Deferred income taxes									(10.8)	(16.0)	28.3
Engineered Materials
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Deferred income taxes									20.6
Discontinued Operations, Held-for-sale | Engineered Materials
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net sales									228.0	175.6	208.6
Cost of sales									181.3	134.5	161.9
Selling, general and administrative									19.8	17.8	19.4
Restructuring charges									0.0	0.6	0.0
Operating profit									26.9	22.7	27.3
Miscellaneous expense, net									(1.3)	0.0	(0.5)
Income from discontinued operations									25.6	22.7	26.8
Income tax (benefit) provision									$ (15.5)	4.8	5.8
Income from discontinued operations, net of tax										$ 17.9	$ 21.0