Fair Value (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Assets:
Short-term investments	$ 20.6	$ 23.8
Contingent Purchase Price Obligations [Member]
Changes in Level 3 Contingent Purchase Price Obligations [Roll Forward]
Balance January 1	142.6	93.8	13.8
Acquisitions	165.2	74.1	87.8
Payments	(32.2)	(22.1)	(9.6)
Foreign currency translation	3.8	(3.0)	0.1
Balance December 31	266.2	142.6	93.8
Contingent Purchase Price Obligations [Member] \| Interest Expense [Member]
Changes in Level 3 Contingent Purchase Price Obligations [Roll Forward]
Revaluation and interest	(13.2)	(0.2)	1.7
Carrying Amount [Member]
Assets:
Cash and cash equivalents	2,678.3	1,781.2
Short-term investments	20.6	23.8
Forward foreign exchange contracts	0.5
Available-for-sale securities	3.9	3.8
Cost method investments	23.1	23.6
Liabilities:
Short-term borrowings	6.4	9.5
Forward foreign exchange contracts		0.1
Contingent purchase price obligations	266.2	142.6
Debt	4,448.9	3,183.6
Fair Value [Member]
Assets:
Cash and cash equivalents	2,678.3	1,781.2
Short-term investments	20.6	23.8
Forward foreign exchange contracts	0.5
Available-for-sale securities	3.9	3.8
Cost method investments	23.1	23.6
Liabilities:
Short-term borrowings	6.4	9.5
Forward foreign exchange contracts		0.1
Contingent purchase price obligations	266.2	142.6
Debt	4,857.3	3,370.5
Fair Value, Measurements, Recurring [Member] \| Level 1
Assets:
Cash and cash equivalents	2,678.3	1,781.2
Short-term investments	20.6	23.8
Available-for-sale securities	3.9	3.8
Fair Value, Measurements, Recurring [Member] \| Level 2
Liabilities:
Forward foreign exchange contracts		0.1
Fair Value, Measurements, Recurring [Member] \| Level 3
Liabilities:
Contingent purchase price obligations	266.2	142.6
Fair Value, Measurements, Recurring [Member] \| Total
Assets:
Cash and cash equivalents	2,678.3	1,781.2
Short-term investments	20.6	23.8
Forward foreign exchange contracts	0.5
Available-for-sale securities	3.9	3.8
Liabilities:
Forward foreign exchange contracts		0.1
Contingent purchase price obligations	$ 266.2	$ 142.6

Amount of liability recognized arising from contingent consideration in a business combination.

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This element represents the portion of the balance sheet assertion valued at fair value by the entity 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. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.

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-Publisher FASB

-Name Accounting Standards Codification

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This element represents the portion of the balance sheet assertion valued at fair value by the entity 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. This item includes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of accounts that have the general characteristics of demand deposits in that the Company may deposit additional funds at any time and also effectively may withdraw funds at any time without prior notice or penalty. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid investments that are both readily convertible to known amounts of cash, and so near their maturity that they present minimal risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months.

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Name Accounting Standards Codification

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-Name Accounting Standards Codification

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-Name Accounting Principles Board Opinion (APB)

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Amount of gain (loss) recognized in earnings, arising from liabilities measured at fair value on a recurring basis using unobservable inputs (level 3).

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-Publisher FASB

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- Definition

Amount of gain (loss) recognized in other comprehensive income, arising from liabilities measured at fair value on a recurring basis using unobservable inputs (level 3).

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

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Issues that have taken place during the period in relation to liabilities measured at fair value and categorized within Level 3 of the fair value hierarchy.

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Settlements that have taken place during the period in relation to liabilities measured at fair value and categorized within Level 3 of the fair value hierarchy.

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This element represents a liability measured at fair value using significant unobservable inputs (Level 3) which is required for reconciliation purposes of beginning and ending balances.

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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.

+ References

No definition available.

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- Definition

Investments which are intended to be sold in the short term (usually less than one year or the normal operating cycle, whichever is longer) including trading securities, available-for-sale securities, held-to-maturity securities, and other short-term investments not otherwise listed in the existing taxonomy.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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-SubTopic 10

-Section S99

-Paragraph 1

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-Name Regulation S-X (SX)

-Number 210

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