Long-lived Assets (Schedule of Changes in Carrying Amount of Goodwill) (Details) $ in Millions	3 Months Ended
Mar. 31, 2019 USD ($)
Goodwill [Roll Forward]
January 1, 2019	$ 13,715.8
Acquisitions and related adjustments	(0.6)
Foreign currency translation adjustments	34.7
March 31, 2019	13,749.9
U.K./Ireland
Goodwill [Roll Forward]
January 1, 2019	7,671.0
Acquisitions and related adjustments	0.0
Foreign currency translation adjustments	138.0
March 31, 2019	7,809.0
Belgium
Goodwill [Roll Forward]
January 1, 2019	2,576.3
Acquisitions and related adjustments	(0.6)
Foreign currency translation adjustments	(52.5)
March 31, 2019	2,523.2
Switzerland
Goodwill [Roll Forward]
January 1, 2019	2,903.9
Acquisitions and related adjustments	0.0
Foreign currency translation adjustments	(37.5)
March 31, 2019	2,866.4
Central and Eastern Europe
Goodwill [Roll Forward]
January 1, 2019	564.6
Acquisitions and related adjustments	0.0
Foreign currency translation adjustments	(13.3)
March 31, 2019	$ 551.3

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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