Long-lived Assets (Schedule of Changes in Carrying Amount of Goodwill) (Details) $ in Millions	3 Months Ended
Mar. 31, 2018 USD ($)
Goodwill [Roll Forward]
January 1, 2018	$ 18,547.4
March 31, 2018	19,000.5
Operating Segments [Member]
Goodwill [Roll Forward]
January 1, 2018	18,547.4
Acquisitions and related adjustments	(47.9)
Foreign currency translation adjustments	501.0
March 31, 2018	19,000.5
Operating Segments [Member] \| U.K./Ireland [Member]
Goodwill [Roll Forward]
January 1, 2018	8,134.1
Acquisitions and related adjustments	0.0
Foreign currency translation adjustments	292.2
March 31, 2018	8,426.3
Operating Segments [Member] \| Belgium [Member]
Goodwill [Roll Forward]
January 1, 2018	2,681.7
Acquisitions and related adjustments	(50.0)
Foreign currency translation adjustments	55.0
March 31, 2018	2,686.7
Operating Segments [Member] \| Germany [Member]
Goodwill [Roll Forward]
January 1, 2018	3,434.5
Acquisitions and related adjustments	0.0
Foreign currency translation adjustments	77.0
March 31, 2018	3,511.5
Operating Segments [Member] \| Switzerland/Austria [Member]
Goodwill [Roll Forward]
January 1, 2018	2,931.3
Acquisitions and related adjustments	0.0
Foreign currency translation adjustments	50.5
March 31, 2018	2,981.8
Operating Segments [Member] \| Central and Eastern Europe [Member]
Goodwill [Roll Forward]
January 1, 2018	1,353.5
Acquisitions and related adjustments	2.1
Foreign currency translation adjustments	26.3
March 31, 2018	1,381.9
Operating Segments [Member] \| Central and Corporate [Member]
Goodwill [Roll Forward]
January 1, 2018	12.3
Acquisitions and related adjustments	0.0
Foreign currency translation adjustments	0.0
March 31, 2018	$ 12.3

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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=77989000&loc=SL49117168-202975

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 25
-Paragraph 16
-URI http://asc.fasb.org/extlink&oid=84229725&loc=d3e961-128460

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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