Discontinued Operations (Schedule of Business Details and Line Items Comprising Discontinued Operations on Statements of Operations and Comprehensive Income) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
(Loss) gain from disposal of discontinued businesses, before income tax			$ (0.4)	$ (4.4)
(Loss) from disposal of discontinued businesses, net of tax expense (benefit)			1.7	(1.4)
(Loss) gain from disposal of discontinued businesses, net of tax	$ 0.0	$ (0.2)	(2.1)	(3.0)
Net (loss) from discontinued operations	0.0	(0.2)	(2.1)	(3.0)
EMEA and Pacific Rim Business [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
(Loss) gain from disposal of discontinued businesses, before income tax	$ 0.0	(0.2)	(0.4)	(5.2)
(Loss) from disposal of discontinued businesses, net of tax expense (benefit)		0.0	1.7	(1.4)
(Loss) gain from disposal of discontinued businesses, net of tax		(0.2)	(2.1)	(3.8)
Net (loss) from discontinued operations		$ (0.2)	$ (2.1)	(3.8)
European Resilient Flooring [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
(Loss) gain from disposal of discontinued businesses, before income tax				0.8
(Loss) from disposal of discontinued businesses, net of tax expense (benefit)				0.0
(Loss) gain from disposal of discontinued businesses, net of tax				0.8
Net (loss) from discontinued operations				$ 0.8