Fair Value (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Assets:
Cash and cash equivalents	$ 2,605.2	$ 2,388.1
Short-term investments	14.5	2.2
Available-for-sale securities	4.8	4.9
Interest rate and foreign currency derivative instruments	32.4	43.1
Cost method investments	21.5	21.8
Liabilities:
Short-term debt	5.2	7.2
Interest rate and foreign currency derivative instruments	15.9	0.4
Contingent purchase price obligations	322.0	300.7
Long-term debt, including current portion	4,655.9	4,754.9
Carrying Amount
Assets:
Cash and cash equivalents	2,605.2	2,388.1
Short-term investments	14.5	2.2
Available-for-sale securities	4.8	4.9
Interest rate and foreign currency derivative instruments	32.4	43.1
Cost method investments	21.5	21.8
Liabilities:
Short-term debt	5.2	7.2
Interest rate and foreign currency derivative instruments	15.9	0.4
Contingent purchase price obligations	322.0	300.7
Long-term debt, including current portion	4,565.6	4,542.5
Contingent purchase price obligations
Changes in Level 3 Contingent Purchase Price Obligations [Roll Forward]
January 1	300.7	220.2
Acquisitions	98.9	167.1
Revaluation and interest	21.8	11.0
Payments	(58.6)	(83.2)
Deferred payment	(21.4)	0.0
Foreign currency translation	(19.4)	(14.4)
December 31	322.0	300.7
Fair Value, Measurements, Recurring [Member]
Assets:
Cash and cash equivalents	2,605.2	2,388.1
Short-term investments	14.5	2.2
Available-for-sale securities	4.8	4.9
Interest rate and foreign currency derivative instruments	32.4	43.1
Liabilities:
Interest rate and foreign currency derivative instruments	15.9
Foreign currency derivative instruments		0.4
Contingent purchase price obligations	322.0	300.7
Fair Value, Measurements, Recurring [Member] | Level 1
Assets:
Cash and cash equivalents	2,605.2	2,388.1
Short-term investments	14.5	2.2
Available-for-sale securities	4.8	4.9
Fair Value, Measurements, Recurring [Member] | Level 2
Assets:
Interest rate and foreign currency derivative instruments	32.4	43.1
Liabilities:
Interest rate and foreign currency derivative instruments	15.9
Foreign currency derivative instruments		0.4
Fair Value, Measurements, Recurring [Member] | Level 3
Liabilities:
Contingent purchase price obligations	$ 322.0	$ 300.7