Goodwill and Intangible Assets (Schedule of Goodwill and Intangible Assets) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Schedule Of Intangible Assets And Goodwill [Line Items]
Goodwill, Estimated Useful Life	Indefinite
Amortizing intangible assets, Gross Carrying Amount	$ 319.0	$ 278.1
Amortizing intangible assets, Accumulated Amortization	208.7	187.7
Non-amortizing intangible assets	347.2	321.5
Total intangible assets	666.2	599.6
Business acquisition, goodwill	$ 160.7	53.0
Trademarks And Brand Names [Member]
Schedule Of Intangible Assets And Goodwill [Line Items]
Non-amortizing intangible assets, Estimated Useful Life	Indefinite
Customer Relationships [Member]
Schedule Of Intangible Assets And Goodwill [Line Items]
Amortizing intangible assets, Gross Carrying Amount	$ 200.6	188.9
Amortizing intangible assets, Accumulated Amortization	$ 128.9	114.9
Customer Relationships [Member] | Minimum [Member]
Schedule Of Intangible Assets And Goodwill [Line Items]
Amortizing intangible assets, Estimated Useful Life	1 year
Customer Relationships [Member] | Maximum [Member]
Schedule Of Intangible Assets And Goodwill [Line Items]
Amortizing intangible assets, Estimated Useful Life	20 years
Developed Technology [Member]
Schedule Of Intangible Assets And Goodwill [Line Items]
Amortizing intangible assets, Gross Carrying Amount	$ 92.1	85.0
Amortizing intangible assets, Accumulated Amortization	$ 77.9	72.1
Developed Technology [Member] | Minimum [Member]
Schedule Of Intangible Assets And Goodwill [Line Items]
Amortizing intangible assets, Estimated Useful Life	13 years
Developed Technology [Member] | Maximum [Member]
Schedule Of Intangible Assets And Goodwill [Line Items]
Amortizing intangible assets, Estimated Useful Life	19 years
Software {Member]
Schedule Of Intangible Assets And Goodwill [Line Items]
Amortizing intangible assets, Estimated Useful Life	7 years
Amortizing intangible assets, Gross Carrying Amount	$ 9.1
Trademarks And Brand Names [Member]
Schedule Of Intangible Assets And Goodwill [Line Items]
Amortizing intangible assets, Gross Carrying Amount	4.0	3.9
Amortizing intangible assets, Accumulated Amortization	$ 1.3	0.6
Trademarks And Brand Names [Member] | Minimum [Member]
Schedule Of Intangible Assets And Goodwill [Line Items]
Amortizing intangible assets, Estimated Useful Life	5 years
Trademarks And Brand Names [Member] | Maximum [Member]
Schedule Of Intangible Assets And Goodwill [Line Items]
Amortizing intangible assets, Estimated Useful Life	10 years
Noncompete Agreements [Member]
Schedule Of Intangible Assets And Goodwill [Line Items]
Amortizing intangible assets, Gross Carrying Amount	$ 6.3	0.2
Amortizing intangible assets, Accumulated Amortization	$ 0.4
Noncompete Agreements [Member] | Minimum [Member]
Schedule Of Intangible Assets And Goodwill [Line Items]
Amortizing intangible assets, Estimated Useful Life	3 years
Noncompete Agreements [Member] | Maximum [Member]
Schedule Of Intangible Assets And Goodwill [Line Items]
Amortizing intangible assets, Estimated Useful Life	5 years
Other [Member]
Schedule Of Intangible Assets And Goodwill [Line Items]
Amortizing intangible assets, Estimated Useful Life	Various
Amortizing intangible assets, Gross Carrying Amount	$ 6.9	0.1
Amortizing intangible assets, Accumulated Amortization	$ 0.2	$ 0.1