CONSOLIDATED STATEMENTS OF INCOME (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Revenue:
Net product sales	$ 2,055.2us-gaap_SalesRevenueGoodsNet	$ 1,707.5us-gaap_SalesRevenueGoodsNet
Other revenue	25.6us-gaap_OtherSalesRevenueNet	22.5us-gaap_OtherSalesRevenueNet
Total revenue	2,080.8us-gaap_Revenues	1,730.0us-gaap_Revenues
Expenses:
Cost of goods sold (excluding amortization of acquired intangible assets)	104.0us-gaap_CostOfGoodsSold	86.1us-gaap_CostOfGoodsSold
Research and development	506.0	713.7
Selling, general and administrative	529.2	494.1
Amortization of acquired intangible assets	63.6	65.7
Acquisition related charges, net	19.0	8.6
Total costs and expenses	1,221.8us-gaap_CostsAndExpenses	1,368.2us-gaap_CostsAndExpenses
Operating income	859.0us-gaap_OperatingIncomeLoss	361.8us-gaap_OperatingIncomeLoss
Other income and (expense):
Interest and investment income, net	9.0	6.4
Interest (expense)	(49.2)us-gaap_InterestExpense	(29.3)us-gaap_InterestExpense
Other income (expense), net	8.3us-gaap_OtherNonoperatingIncomeExpense	(6.6)us-gaap_OtherNonoperatingIncomeExpense
Income before income taxes	827.1	332.3
Income tax provision	108.2us-gaap_IncomeTaxExpenseBenefit	52.6us-gaap_IncomeTaxExpenseBenefit
Net income	$ 718.9us-gaap_ProfitLoss	$ 279.7us-gaap_ProfitLoss
Net income per common share (Note1):
Basic (in dollars per share)	$ 0.90us-gaap_EarningsPerShareBasic	$ 0.34us-gaap_EarningsPerShareBasic
Diluted (in dollars per share)	$ 0.86us-gaap_EarningsPerShareDiluted	$ 0.33us-gaap_EarningsPerShareDiluted
Weighted average shares (Note 1):
Basic (in shares)	798.9	811.5
Diluted (in shares)	834.1	845.1

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Amount of the cost of borrowed funds accounted for as interest expense.

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The costs incurred in a planned search or critical investigation aimed at discovery of new knowledge with the hope that such knowledge will be useful in developing a new product or service, a new process or technique, or in bringing about a significant improvement to an existing product or process; or to translate research findings or other knowledge into a plan or design for a new product or process or for a significant improvement to an existing product or process whether intended for sale or the entity's use, during the reporting period charged to research and development projects, excluding in-process research and development acquired in a business combination consummated during the period. Excludes software research and development, which has a separate concept.

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