Intangible Assets - Accumulated Impairment, Changes in Goodwill and Other Indefinite-Lived Intangibles (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2012
Intangible Assets
Goodwill, Accumulated impairment loss				$ 606.3
Other indefinite-lived intangible assets, Accumulated impairment loss				$ 37.1
Summary of the changes in the carrying amount of goodwill and other indefinite-lived intangible assets
Goodwill, Beginning balance	$ 1,752.0	$ 1,660.5
Goodwill, Additions	146.6	144.1
Goodwill, Disposals	(3.9)	(13.8)
Goodwill, Foreign currency translation	16.3	(38.8)
Goodwill, Ending balance	1,911.0	1,752.0	$ 1,660.5
Other indefinite-lived intangible assets, Beginning Balance	486.2	474.0
Other indefinite-lived intangible assets, Additions	67.4	29.8
Other indefinite-lived intangible assets, Disposals	(1.2)	(0.5)
Other indefinite-lived intangible assets, Impairment	(1.9)	(5.8)	0.0
Other indefinite-lived intangible assets, Foreign currency translation	1.7	(11.3)
Other indefinite-lived intangible assets, Ending Balance	$ 552.2	$ 486.2	$ 474.0