Valuation and Qualifying Accounts (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Allowance for Doubtful Accounts
Valuation And Qualifying Accounts Disclosure [Line Items]
Beginning Balance	$ 2.4	$ 3.1	$ 2.9
Additions, Charged to Expenses	1.4	0.4	1.1
Additions, Acquired	0.0	0.0	0.0
Deductions, Amounts Written Off	(0.1)	(1.1)	(0.8)
Foreign Exchange	0.0	0.0	(0.1)
Ending Balance	3.7	2.4	3.1
Allowance for Cash Discounts
Valuation And Qualifying Accounts Disclosure [Line Items]
Beginning Balance	5.1	5.0	5.1
Additions, Charged to Expenses	96.0	86.9	83.8
Additions, Acquired	0.4	0.0	0.0
Deductions, Amounts Written Off	(95.5)	(86.8)	(83.8)
Foreign Exchange	0.0	0.0	(0.1)
Ending Balance	6.0	5.1	5.0
Sales Returns and Allowances
Valuation And Qualifying Accounts Disclosure [Line Items]
Beginning Balance	13.0	12.1	13.9
Additions, Charged to Expenses	110.9	97.2	93.3
Additions, Acquired	0.4	0.0	0.0
Deductions, Amounts Written Off	(99.8)	(96.4)	(95.0)
Foreign Exchange	0.0	0.1	(0.1)
Ending Balance	$ 24.5	$ 13.0	$ 12.1