Fair Value (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2015
Assets:
Cash and cash equivalents	$ 1,747.3		$ 2,605.2
Short-term investments	2.7		14.5
Available-for-sale securities	4.8		4.8
Interest rate and foreign currency derivative instruments	20.4		32.4
Cost method investments	14.2		21.5
Liabilities:
Short-term debt	38.8		5.2
Interest rate and foreign currency derivative instruments	55.2		15.9
Contingent purchase price obligations	424.1		322.0
Long-term debt, including current portion	4,744.1		4,655.9
Carrying Amount
Assets:
Cash and cash equivalents	1,747.3		2,605.2
Short-term investments	2.7		14.5
Available-for-sale securities	4.8		4.8
Interest rate and foreign currency derivative instruments	20.4		32.4
Cost method investments	14.2		21.5
Liabilities:
Short-term debt	38.8		5.2
Interest rate and foreign currency derivative instruments	55.2		15.9
Contingent purchase price obligations	424.1		322.0
Long-term debt, including current portion	4,612.9		4,565.6
Contingent purchase price obligations
Changes in Level 3 Contingent Purchase Price Obligations [Roll Forward]
January 1	322.0	$ 300.7
Acquisitions	102.5	46.3
Revaluation and interest	12.3	2.2
Payments	(22.7)	(1.8)
Foreign currency translation	10.0	(14.9)
March 31	424.1	$ 332.5
Fair Value, Measurements, Recurring [Member]
Assets:
Cash and cash equivalents	1,747.3		2,605.2
Short-term investments	2.7		14.5
Available-for-sale securities	4.8		4.8
Interest rate and foreign currency derivative instruments	20.4		32.4
Liabilities:
Interest rate and foreign currency derivative instruments	55.2		15.9
Contingent purchase price obligations	424.1		322.0
Fair Value, Measurements, Recurring [Member] | Level 1
Assets:
Cash and cash equivalents	1,747.3		2,605.2
Short-term investments	2.7		14.5
Available-for-sale securities	4.8		4.8
Fair Value, Measurements, Recurring [Member] | Level 2
Assets:
Interest rate and foreign currency derivative instruments	20.4		32.4
Liabilities:
Interest rate and foreign currency derivative instruments	55.2		15.9
Fair Value, Measurements, Recurring [Member] | Level 3
Liabilities:
Contingent purchase price obligations	$ 424.1		$ 322.0