Intangible Assets (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2012	Mar. 31, 2011	Dec. 31, 2011
Goodwill, gross carrying value	$ 9,154.0		$ 9,026.6
Goodwill, accumulated amortization	579.5		570.3
Goodwill, net carrying value	8,574.5	8,393.4
Other identifiable intangible assets subject to amortization, gross carrying value	904.4		885.3
Other identifiable intangible assets subject to amortization, accumulated amortization	441.6		416.9
Other identifiable intangible assets subject to amortization, net carrying value	462.8		468.4
Goodwill [Roll Forward]
Goodwill, Balance January 1	8,456.3	7,809.1
Goodwill, Acquisitions	35.4	463.8
Goodwill, Dispositions	(0.5)	(5.4)
Goodwill, Foreign currency translation	83.3	125.9
Goodwill, Balance March 31	8,574.5	8,393.4
Goodwill, impairment losses	0
Goodwill, accumulated impairment losses	0
Goodwill, acquisitions of noncontrolling interests	8.5	111.9
Purchased and internally developed software [Member]
Other identifiable intangible assets subject to amortization, gross carrying value	278.0		270.0
Other identifiable intangible assets subject to amortization, accumulated amortization	216.6		210.3
Other identifiable intangible assets subject to amortization, net carrying value	61.4		59.7
Customer related and other [Member]
Other identifiable intangible assets subject to amortization, gross carrying value	626.4		615.3
Other identifiable intangible assets subject to amortization, accumulated amortization	225.0		206.6
Other identifiable intangible assets subject to amortization, net carrying value	$ 401.4		$ 408.7