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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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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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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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Fair Value (Details) (USD $) In Millions, unless otherwise specified															6 Months Ended
	Jun. 30, 2013	Dec. 31, 2012	Jun. 30, 2013 Carrying Amount	Dec. 31, 2012 Carrying Amount	Jun. 30, 2013 Fair Value	Dec. 31, 2012 Fair Value	Jun. 30, 2013 Fair Value, Measurements, Recurring [Member] Level 1	Dec. 31, 2012 Fair Value, Measurements, Recurring [Member] Level 1	Jun. 30, 2013 Fair Value, Measurements, Recurring [Member] Level 2	Dec. 31, 2012 Fair Value, Measurements, Recurring [Member] Level 2	Jun. 30, 2013 Fair Value, Measurements, Recurring [Member] Level 3	Dec. 31, 2012 Fair Value, Measurements, Recurring [Member] Level 3	Jun. 30, 2013 Fair Value, Measurements, Recurring [Member] Total	Dec. 31, 2012 Fair Value, Measurements, Recurring [Member] Total	Jun. 30, 2013 Contingent Purchase Price Obligations [Member]
Assets:
Cash and cash equivalents			$ 1,399.9	$ 2,678.3	$ 1,399.9	$ 2,678.3	$ 1,399.9	$ 2,678.3					$ 1,399.9	$ 2,678.3
Short-term investments	14.7	20.6	14.7	20.6	14.7	20.6	14.7	20.6					14.7	20.6
Forward foreign exchange contracts			0.5	0.5	0.5	0.5			0.5	0.5			0.5	0.5
Available-for-sale securities			4.5	3.9	4.5	3.9	4.5	3.9					4.5	3.9
Cost method investments			22.5	23.1	22.5	23.1
Liabilities:
Short-term borrowings			12.8	6.4	12.8	6.4
Forward foreign exchange contracts			0.7	0	0.7	0			0.7				0.7
Contingent purchase price obligations			232.2	266.2	232.2	266.2					232.2	266.2	232.2	266.2
Debt			4,037.8	4,448.9	4,252.8	4,857.3
Changes in contingent purchase price obligations, payments															$ 31.8