Goodwill and Intangible Assets (Changes in Carrying Amount of Goodwill) (Details) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2020	Jun. 30, 2020
Goodwill [Roll Forward]
Goodwill, gross, beginning balance	$ 9,975.6
Accumulated impairment losses, beginning balance	(385.0)
Foreign currency translation	(67.3)
Goodwill, net, beginning balance	9,590.6
Accumulated impairment losses, ending balance	(385.0)
Goodwill, gross, ending balance	9,908.3
Goodwill, net, ending balance	$ 9,590.6	$ 9,523.3
Goodwill, Impaired, Change in Estimate, Period	5 years
Fair Value Inputs, Long-term Revenue Growth Rate, Terminal Year	2.00%
North America Segment
Goodwill [Roll Forward]
Goodwill, gross, beginning balance	$ 3,708.4
Accumulated impairment losses, beginning balance	(385.0)
Foreign currency translation	(39.0)
Goodwill, net, beginning balance	3,323.4
Accumulated impairment losses, ending balance	(385.0)
Goodwill, gross, ending balance	3,669.4
Goodwill, net, ending balance	3,323.4	3,284.4
Europe Segment
Goodwill [Roll Forward]
Goodwill, gross, beginning balance	4,548.6
Accumulated impairment losses, beginning balance	0.0
Foreign currency translation	4.6
Goodwill, net, beginning balance	4,548.6
Accumulated impairment losses, ending balance	0.0
Goodwill, gross, ending balance	4,553.2
Goodwill, net, ending balance	4,548.6	$ 4,553.2
Reporting Unit, Percentage of Fair Value in Excess of Carrying Amount		11.00%
Reporting Unit, Amount of Fair Value in Excess of Carrying Amount		$ 1,300.0
Rest of World Segment
Goodwill [Roll Forward]
Goodwill, gross, beginning balance	1,718.6
Accumulated impairment losses, beginning balance	0.0
Foreign currency translation	(32.9)
Goodwill, net, beginning balance	1,718.6
Accumulated impairment losses, ending balance	0.0
Goodwill, gross, ending balance	1,685.7
Goodwill, net, ending balance	$ 1,718.6	$ 1,685.7
Measurement Input, Estimated Tax Rate
Goodwill [Roll Forward]
Goodwill Impairment Test, Measurement Input		0.255
Measurement Input, Control Premium
Goodwill [Roll Forward]
Goodwill Impairment Test, Measurement Input		0.150
Measurement Input, Long-term Revenue Growth Rate
Goodwill [Roll Forward]
Goodwill Impairment Test, Measurement Input		0.075
Goodwill | Measurement Input, Discount Rate
Goodwill [Roll Forward]
Goodwill Impairment Test, Measurement Input		0.110
Minimum | Measurement Input, EBITDA Multiple
Goodwill [Roll Forward]
Goodwill Impairment Test, Measurement Input		8.0
Maximum | Measurement Input, EBITDA Multiple
Goodwill [Roll Forward]
Goodwill Impairment Test, Measurement Input		9.5
Increased Discount Rate | Measurement Input, Discount Rate
Goodwill [Roll Forward]
Goodwill Impairment Test, Measurement Input, Increase		0.035
Reduction in Terminal Value Growth Rate | Measurement Input, Long-term Revenue Growth Rate
Goodwill [Roll Forward]
Goodwill Impairment Test, Measurement Input, Reduction		0.035