Fair Value (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Assets:
Cash and cash equivalents	$ 2,388.1	$ 2,710.5
Short-term investments	2.2us-gaap_ShortTermInvestments	18.2us-gaap_ShortTermInvestments
Available-for-sale securities	4.9us-gaap_AvailableForSaleSecurities	4.9us-gaap_AvailableForSaleSecurities
Interest rate and foreign currency derivative instruments	43.1us-gaap_DerivativeAssets	2.2us-gaap_DerivativeAssets
Cost method investments	21.8	22.2
Liabilities:
Short-term borrowings	7.2us-gaap_ShorttermDebtFairValue	5.9us-gaap_ShorttermDebtFairValue
Foreign currency derivative instruments	0.4	0.1
Contingent interest derivative	0	2.1
Contingent purchase price obligations	300.7	220.2
Debt	4,754.9us-gaap_LongTermDebtFairValue	4,302.7us-gaap_LongTermDebtFairValue
Contingent purchase price obligations
Changes in Level 3 Contingent Purchase Price Obligations [Roll Forward]
January 1	220.2	266.2
Acquisitions	167.1	35.8
Revaluation and interest	11.0	(10.9)
Payments	(83.2)	(70.5)
Foreign currency translation	(14.4)	(0.4)
December 31	300.7	220.2
Carrying Amount
Assets:
Cash and cash equivalents	2,388.1	2,710.5
Short-term investments	2.2	18.2
Available-for-sale securities	4.9	4.9
Interest rate and foreign currency derivative instruments	43.1	2.2
Cost method investments	21.8	22.2
Liabilities:
Short-term borrowings	7.2	5.9
Foreign currency derivative instruments	0.4	0.1
Contingent interest derivative	0	2.1
Contingent purchase price obligations	300.7	220.2
Debt	4,563.0	4,033.8
Fair Value, Measurements, Recurring [Member]
Assets:
Cash and cash equivalents	2,388.1	2,710.5
Short-term investments	2.2	18.2
Available-for-sale securities	4.9	4.9
Interest rate and foreign currency derivative instruments	43.1
Foreign currency derivative instruments		2.2
Liabilities:
Foreign currency derivative instruments	0.4	0.1
Contingent interest derivative		2.1
Contingent purchase price obligations	300.7	220.2
Fair Value, Measurements, Recurring [Member] \| Level 1
Assets:
Cash and cash equivalents	2,388.1	2,710.5
Short-term investments	2.2	18.2
Available-for-sale securities	4.9	4.9
Fair Value, Measurements, Recurring [Member] \| Level 2
Assets:
Interest rate and foreign currency derivative instruments	43.1
Foreign currency derivative instruments		2.2
Liabilities:
Foreign currency derivative instruments	0.4	0.1
Contingent interest derivative		2.1
Fair Value, Measurements, Recurring [Member] \| Level 3
Liabilities:
Contingent purchase price obligations	$ 300.7	$ 220.2

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The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

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