Long-lived Assets (Schedule of Changes in Carrying Amount of Goodwill) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Goodwill [Roll Forward]
Goodwill beginning balance	$ 14,354.1	$ 12,758.5
Acquisitions and related adjustments	26.6	340.9
Foreign currency translation adjustments	(664.9)	1,254.7
Goodwill ending balance	13,715.8	14,354.1
U.K./Ireland
Goodwill [Roll Forward]
Goodwill beginning balance	8,134.1	7,412.3
Acquisitions and related adjustments	2.0	2.3
Foreign currency translation adjustments	(465.1)	719.5
Goodwill ending balance	7,671.0	8,134.1
Belgium
Goodwill [Roll Forward]
Goodwill beginning balance	2,681.7	2,032.7
Acquisitions and related adjustments	24.9	338.6
Foreign currency translation adjustments	(130.3)	310.4
Goodwill ending balance	2,576.3	2,681.7
Switzerland
Goodwill [Roll Forward]
Goodwill beginning balance	2,931.3	2,805.6
Acquisitions and related adjustments	(0.3)	0.0
Foreign currency translation adjustments	(27.1)	125.7
Goodwill ending balance	2,903.9	2,931.3
Central and Eastern Europe
Goodwill [Roll Forward]
Goodwill beginning balance	607.0	507.9
Acquisitions and related adjustments	0.0	0.0
Foreign currency translation adjustments	(42.4)	99.1
Goodwill ending balance	$ 564.6	$ 607.0

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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