Intangible Assets (Details) (USD $) In Millions, unless otherwise specified	6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Dec. 31, 2011
Goodwill, gross carrying value	$ 9,167.8		$ 9,026.6
Goodwill, accumulated amortization	568.2		570.3
Goodwill, net carrying value	8,599.6	8,502.4
Other identifiable intangible assets subject to amortization, gross carrying value	894.4		885.3
Other identifiable intangible assets subject to amortization, accumulated amortization	449.3		416.9
Other identifiable intangible assets subject to amortization, net carrying value	445.1		468.4
Goodwill [Roll Forward]
Goodwill, Balance January 1	8,456.3	7,809.1
Goodwill, Acquisitions	162.3	538.4
Goodwill, Dispositions	(0.5)	(6.1)
Goodwill, Foreign currency translation	(18.5)	161.0
Goodwill, Balance June 30	8,599.6	8,502.4
Goodwill, impairment losses	0
Goodwill, accumulated impairment losses	0
Goodwill, acquisitions of noncontrolling interests	8.0	115.8
Purchased and internally developed software [Member]
Other identifiable intangible assets subject to amortization, gross carrying value	270.1		270.0
Other identifiable intangible assets subject to amortization, accumulated amortization	209.0		210.3
Other identifiable intangible assets subject to amortization, net carrying value	61.1		59.7
Customer related and other [Member]
Other identifiable intangible assets subject to amortization, gross carrying value	624.3		615.3
Other identifiable intangible assets subject to amortization, accumulated amortization	240.3		206.6
Other identifiable intangible assets subject to amortization, net carrying value	$ 384.0		$ 408.7